[Title 29 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2014 Edition]
[From the U.S. Government Publishing Office]
[[Page i]]
Title 29
Labor
________________________
Part 1910 (Sec. 1910.1000 to end of part 1910)
Revised as of July 1, 2013
Containing a codification of documents of general
applicability and future effect
As of July 1, 2013
Published by the Office of the Federal Register
National Archives and Records Administration as a
Special Edition of the Federal Register
[[Page ii]]
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Table of Contents
Page
Explanation................................................. v
Title 29:
SUBTITLE B--Regulations Relating to Labor (Continued)
Chapter XVII--Occupational Safety and Health
Administration, Department of Labor (Continued) 5
Finding Aids:
Table of CFR Titles and Chapters........................ 655
Alphabetical List of Agencies Appearing in the CFR...... 675
Table of OMB Control Numbers............................ 685
List of CFR Sections Affected........................... 687
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----------------------------
Cite this Code: CFR
To cite the regulations in
this volume use title,
part and section number.
Thus, 29 CFR 1910.1000
refers to title 29, part
1910, section 1000.
----------------------------
[[Page v]]
EXPLANATION
The Code of Federal Regulations is a codification of the general and
permanent rules published in the Federal Register by the Executive
departments and agencies of the Federal Government. The Code is divided
into 50 titles which represent broad areas subject to Federal
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parts covering specific regulatory areas.
Each volume of the Code is revised at least once each calendar year
and issued on a quarterly basis approximately as follows:
Title 1 through Title 16.................................as of January 1
Title 17 through Title 27..................................as of April 1
Title 28 through Title 41...................................as of July 1
Title 42 through Title 50................................as of October 1
The appropriate revision date is printed on the cover of each
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LEGAL STATUS
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OMB CONTROL NUMBERS
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Federal agencies to display an OMB control number with their information
collection request.
[[Page vi]]
Many agencies have begun publishing numerous OMB control numbers as
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``[RESERVED]'' TERMINOLOGY
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(b) The matter incorporated is in fact available to the extent
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(c) The incorporating document is drafted and submitted for
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this volume.
[[Page vii]]
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Charles A. Barth,
Director,
Office of the Federal Register.
July 1, 2013.
[[Page ix]]
THIS TITLE
Title 29--Labor is composed of nine volumes. The parts in these
volumes are arranged in the following order: Parts 0-99, parts 100-499,
parts 500-899, parts 900-1899, part 1900-Sec. 1910.999, part 1910.1000-
end of part 1910, parts 1911-1925, part 1926, and part 1927 to end. The
contents of these volumes represent all current regulations codified
under this title as of July 1, 2013.
The OMB control numbers for title 29 CFR part 1910 appear in Sec.
1910.8. For the convenience of the user, Sec. 1910.8 appears in the
Finding Aids section of the volume containing Sec. 1910.1000 to the
end.
Subject indexes appear following the occupational safety and health
standards (part 1910).
For this volume, Jonn V. Lilyea was Chief Editor. The Code of
Federal Regulations publication program is under the direction of
Michael L. White, assisted by Ann Worley.
[[Page 1]]
TITLE 29--LABOR
(This book contains part 1910,Sec. 1910.1000 to end of part 1910)
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SUBTITLE B--Regulations Relating to Labor (Continued)
Part
chapter xvii--Occupational Safety and Health Administration,
Department of Labor (Continued)........................... 1910
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Subtitle B--Regulations Relating to Labor (Continued)
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CHAPTER XVII--OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT
OF LABOR (CONTINUED)
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Part Page
1910 Occupational Safety and Health Standards
(Continued)............................. 7
Subject index for 29 CFR part 1910--
Occupational safety and health standards 609
[[Page 7]]
PART 1910_OCCUPATIONAL SAFETY AND HEALTH STANDARDS (CONTINUED)--
Table of Contents
Subpart Z_Toxic and Hazardous Substances
Sec.
1910.1000 Air contaminants.
1910.1001 Asbestos.
1910.1002 Coal tar pitch volatiles; interpretation of term.
1910.1003 13 Carcinogens (4-Nitrobiphenyl, etc.).
1910.1004 alpha-Naphthylamine.
1910.1005 [Reserved]
1910.1006 Methyl chloromethyl ether.
1910.1007 3,'--Dichlorobenzidine (and its salts).
1910.1008 bis-Chloromethyl ether.
1910.1009 beta-Naphthylamine.
1910.1010 Benzidine.
1910.1011 4-Aminodiphenyl.
1910.1012 Ethyleneimine.
1910.1013 beta-Propiolactone.
1910.1014 2-Acetylaminofluorene.
1910.1015 4-Dimethylaminoazobenzene.
1910.1016 N-Nitrosodimethylamine.
1910.1017 Vinyl chloride.
1910.1018 Inorganic arsenic.
1910.1020 Access to employee exposure and medical records.
1910.1025 Lead.
1910.1026 Chromium (VI).
1910.1027 Cadmium.
1910.1028 Benzene.
1910.1029 Coke oven emissions.
1910.1030 Bloodborne pathogens.
1910.1043 Cotton dust.
1910.1044 1,2-dibromo-3-chloropropane.
1910.1045 Acrylonitrile.
1910.1047 Ethylene oxide.
1910.1048 Formaldehyde.
1910.1050 Methylenedianiline.
1910.1051 1,3-Butadiene.
1910.1052 Methylene Chloride.
1910.1096 Ionizing radiation.
1910.1200 Hazard communication.
1910.1201 Retention of DOT markings, placards and labels.
1910.1450 Occupational exposure to hazardous chemicals in laboratories.
Subpart Z_Toxic and Hazardous Substances
Authority: Sections 4, 6, 8 of the Occupational Safety and Health
Act of 1970 (29 U.S.C. 653, 655, 657); Secretary of Labor's Order No.
12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 FR 35736), 1-90 (55 FR
9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 5-2002 (67 FR 65008), 5-
2007 (72 FR 31159), 4-2010 (75 FR 55355), or 1-2012 (77 FR 3912), as
applicable; and 29 CFR part 1911.
All of subpart Z issued under section 6(b) of the Occupational
Safety and Health Act of 1970, except those substances that have
exposure limits listed in Tables Z-1, Z-2, and Z-3 of 29 CFR 1910.1000.
The latter were issued under section 6(a) (29 U.S.C. 655(a)).
Section 1910.1000, Tables Z-1, Z-2 and Z-3 also issued under 5
U.S.C. 553, but not under 29 CFR part 1911 except for the arsenic
(organic compounds), benzene, cotton dust, and chromium (VI) listings.
Section 1910.1001 also issued under section 107 of the Contract Work
Hours and Safety Standards Act (40 U.S.C. 3704) and 5 U.S.C. 553.
Section 1910.1002 also issued under 5 U.S.C. 553, but not under 29
U.S.C. 655 or 29 CFR part 1911.
Sections 1910.1018, 1910.1029, and 1910.1200 also issued under 29
U.S.C. 653.
Section 1910.1030 also issued under Pub. L. 106-430, 114 Stat. 1901.
Section 1910.1201 also issued under 49 U.S.C. 1801-1819 and 5 U.S.C.
533.
Source: 39 FR 23502, June 27, 1974, unless otherwise noted.
Redesignated at 40 FR 23072, May 28, 1975.
Sec. 1910.1000 Air contaminants.
An employee's exposure to any substance listed in Tables Z-1, Z-2,
or Z-3 of this section shall be limited in accordance with the
requirements of the following paragraphs of this section.
(a) Table Z-1--(1) Substances with limits preceded by ``C''--Ceiling
Values. An employee's exposure to any substance in Table Z-1, the
exposure limit of which is preceded by a ``C'', shall at no time exceed
the exposure limit given for that substance. If instantaneous monitoring
is not feasible, then the ceiling shall be assessed as a 15-minute time
weighted average exposure which shall not be exceeded at any time during
the working day.
(2) Other substances--8-hour Time Weighted Averages. An employee's
exposure to any substance in Table Z-1, the exposure limit of which is
not preceded by a ``C'', shall not exceed the 8-hour Time Weighted
Average given for that substance in any 8-hour work shift of a 40-hour
work week.
(b) Table Z-2. An employee's exposure to any substance listed in
Table Z-2 shall not exceed the exposure limits specified as follows:
(1) 8-hour time weighted averages. An employee's exposure to any
substance listed in Table Z-2, in any 8-hour work shift of a 40-hour
work week, shall not
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exceed the 8-hour time weighted average limit given for that substance
in Table Z-2.
(2) Acceptable ceiling concentrations. An employee's exposure to a
substance listed in Table Z-2 shall not exceed at any time during an 8-
hour shift the acceptable ceiling concentration limit given for the
substance in the table, except for a time period, and up to a
concentration not exceeding the maximum duration and concentration
allowed in the column under ``acceptable maximum peak above the
acceptable ceiling concentration for an 8-hour shift.''
(3) Example. During an 8-hour work shift, an employee may be exposed
to a concentration of Substance A (with a 10 ppm TWA, 25 ppm ceiling and
50 ppm peak) above 25 ppm (but never above 50 ppm) only for a maximum
period of 10 minutes. Such exposure must be compensated by exposures to
concentrations less than 10 ppm so that the cumulative exposure for the
entire 8-hour work shift does not exceed a weighted average of 10 ppm.
(c) Table Z-3. An employee's exposure to any substance listed in
Table Z-3, in any 8-hour work shift of a 40-hour work week, shall not
exceed the 8-hour time weighted average limit given for that substance
in the table.
(d) Computation formulae. The computation formula which shall apply
to employee exposure to more than one substance for which 8-hour time
weighted averages are listed in subpart Z of 29 CFR part 1910 in order
to determine whether an employee is exposed over the regulatory limit is
as follows:
(1)(i) The cumulative exposure for an 8-hour work shift shall be
computed as follows:
E = (Ca Ta+Cb Tb+. .
.Cn Tn)/8
Where:
E is the equivalent exposure for the working shift.
C is the concentration during any period of time T where the
concentration remains constant.
T is the duration in hours of the exposure at the concentration C.
The value of E shall not exceed the 8-hour time weighted average
specified in subpart Z of 29 CFR part 1910 for the substance involved.
(ii) To illustrate the formula prescribed in paragraph (d)(1)(i) of
this section, assume that Substance A has an 8-hour time weighted
average limit of 100 ppm noted in Table Z-1. Assume that an employee is
subject to the following exposure:
Two hours exposure at 150 ppm
Two hours exposure at 75 ppm
Four hours exposure at 50 ppm
Substituting this information in the formula, we have
(2x150+2x75+4x50)/8=81.25 ppm
Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted
average limit, the exposure is acceptable.
(2)(i) In case of a mixture of air contaminants an employer shall
compute the equivalent exposure as follows:
Em=(C1/L1+C2/
L2)+. . .(Cn/Ln)
Where:
Em is the equivalent exposure for the mixture.
C is the concentration of a particular contaminant.
L is the exposure limit for that substance specified in subpart Z of 29
CFR part 1910.
The value of Em shall not exceed unity (1).
(ii) To illustrate the formula prescribed in paragraph (d)(2)(i) of
this section, consider the following exposures:
------------------------------------------------------------------------
Actual
concentration
Substance of 8-hour 8-hour TWA
exposure PEL (ppm)
(ppm)
------------------------------------------------------------------------
B........................................... 500 1,000
C........................................... 45 200
D........................................... 40 200
------------------------------------------------------------------------
Substituting in the formula, we have:
Em=500/1,000+45/200+40/200
Em=0.500+0.225+0.200
Em=0.925
Since Em is less than unity (1), the exposure combination is
within acceptable limits.
(e) To achieve compliance with paragraphs (a) through (d) of this
section, administrative or engineering controls must first be determined
and implemented whenever feasible. When such controls are not feasible
to achieve full compliance, protective equipment or any other protective
measures shall be used to keep the exposure of employees to air
contaminants within the limits prescribed in this section. Any equipment
and/or technical measures used for this purpose must be approved for
[[Page 9]]
each particular use by a competent industrial hygienist or other
technically qualified person. Whenever respirators are used, their use
shall comply with 1910.134.
Table Z-1--Limits for Air Contaminants
----------------------------------------------------------------------------------------------------------------
mg/m\3\ (b)
Substance CAS No. (c) ppm (a) \1\ \1\ Skin designation
----------------------------------------------------------------------------------------------------------------
Acetaldehyde.............................. 75-07-0 200 360
Acetic acid............................... 64-19-7 10 25
Acetic anhydride.......................... 108-24-7 5 20
Acetone................................... 67-64-1 1000 2400
Acetonitrile.............................. 75-05-8 40 70
2-Acetylaminofluorine; see 1910.1014...... 53-96-3
Acetylene dichloride; see 1,2-
Dichloroethylene.
Acetylene tetrabromide.................... 79-27-6 1 14
Acrolein.................................. 107-02-8 0.1 0.25
Acrylamide................................ 79-06-1 ............ 0.3 X
Acrylonitrile; see 1910.1045.............. 107-13-1
Aldrin.................................... 309-00-2 ............ 0.25 X
Allyl alcohol............................. 107-18-6 2 5 X
Allyl chloride............................ 107-05-1 1 3
Allyl glycidyl ether (AGE)................ 106-92-3 (C)10 (C)45
Allyl propyl disulfide.................... 2179-59-1 2 12
alpha-Alumina............................. 1344-28-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Aluminum, metal (as Al)................... 7429-90-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
4-Aminodiphenyl; see 1910.1011............ 92-67-1
2-Aminoethanol; see Ethanolamine.
2-Aminopyridine........................... 504-29-0 0.5 2
Ammonia................................... 7664-41-7 50 35
Ammonium sulfamate........................ 7773-06-0
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
n-Amyl acetate............................ 628-63-7 100 525
sec-Amyl acetate.......................... 626-38-0 125 650
Aniline and homologs...................... 62-53-3 5 19 X
Anisidine (o-, p-isomers)................. 29191-52-4 ............ 0.5 X
Antimony and compounds (as Sb)............ 7440-36-0 ............ 0.5
ANTU (alpha Naphthylthiourea)............. 86-88-4 ............ 0.3
Arsenic, inorganic compounds (as As); see 7440-38-2
1910.1018.
Arsenic, organic compounds (as As)........ 7440-38-2 ............ 0.5
Arsine.................................... 7784-42-1 0.05 0.2
Asbestos; see 1910.1001................... (\4\)
Azinphos-methyl........................... 86-50-0 ............ 0.2 X
Barium, soluble compounds (as Ba)......... 7440-39-3 ............ 0.5
Barium sulfate............................ 7727-43-7
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Benomyl................................... 17804-35-2
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Benzene; see 1910.1028.................... 71-43-2
See Table Z-2 for the limits
applicable in the operations or
sectors excluded in 1910.1028 \d\
Benzidine; see 1910.1010.................. 92-87-5
p-Benzoquinone; see Quinone.
Benzo(a)pyrene; see Coal tar pitch
volatiles..
Benzoyl peroxide.......................... 94-36-0 ............ 5
Benzyl chloride........................... 100-44-7 1 5
Beryllium and beryllium compounds (as Be). 7440-41-7 ............ (\2\)
Biphenyl; see Diphenyl.
Bismuth telluride, Undoped................ 1304-82-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Boron oxide............................... 1303-86-2
Total dust............................ .............. ............ 15
Boron trifluoride......................... 7637-07-2 (C)1 (C)3
Bromine................................... 7726-95-6 0.1 0.7
Bromoform................................. 75-25-2 0.5 5 X
Butadiene (1,3-Butadiene); See 29 CFR 106-99-0 1 ppm/5 ppm
1910.1051; 29 CFR 1910.19(l). STEL
[[Page 10]]
Butanethiol; see Butyl mercaptan.
2-Butanone (Methyl ethyl ketone).......... 78-93-3 200 590
2-Butoxyethanol........................... 111-76-2 50 240 X
n-Butyl-acetate........................... 123-86-4 150 710
sec-Butyl acetate......................... 105-46-4 200 950
tert-Butyl acetate........................ 540-88-5 200 950
n-Butyl alcohol........................... 71-36-3 100 300
sec-Butyl alcohol......................... 78-92-2 150 450
tert-Butyl alcohol........................ 75-65-0 100 300
Butylamine................................ 109-73-9 (C)5 (C)15 X
tert-Butyl chromate (as CrO3); see 1189-85-1
1910.1026 \6\.
n-Butyl glycidyl ether (BGE).............. 2426-08-6 50 270
Butyl mercaptan........................... 109-79-5 10 35
p-tert-Butyltoluene....................... 98-51-1 10 60
Cadmium (as Cd); see 1910.1027............ 7440-43-9
Calcium carbonate......................... 1317-65-3
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Calcium hydroxide......................... 1305-62-0
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Calcium oxide............................. 1305-78-8 ............ 5
Calcium silicate.......................... 1344-95-2
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Calcium sulfate........................... 7778-18-9
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Camphor, synthetic........................ 76-22-2 ............ 2
Carbaryl (Sevin).......................... 63-25-2 ............ 5
Carbon black.............................. 1333-86-4 ............ 3.5
Carbon dioxide............................ 124-38-9 5000 9000
Carbon disulfide.......................... 75-15-0 ............ (\2\)
Carbon monoxide........................... 630-08-0 50 55
Carbon tetrachloride...................... 56-23-5 ............ (\2\)
Cellulose................................. 9004-34-6
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Chlordane................................. 57-74-9 ............ 0.5 X
Chlorinated camphene...................... 8001-35-2 ............ 0.5 X
Chlorinated diphenyl oxide................ 55720-99-5 ............ 0.5
Chlorine.................................. 7782-50-5 (C)1 (C)3
Chlorine dioxide.......................... 10049-04-4 0.1 0.3
Chlorine trifluoride...................... 7790-91-2 (C)0.1 (C)0.4
Chloroacetaldehyde........................ 107-20-0 (C)1 (C)3
a-Chloroacetophenone (Phenacyl chloride).. 532-27-4 0.05 0.3
Chlorobenzene............................. 108-90-7 75 350
o-Chlorobenzylidene malononitrile......... 2698-41-1 0.05 0.4
Chlorobromomethane........................ 74-97-5 200 1050
2-Chloro-1,3-butadiene; see beta-
Chloroprene.
Chlorodiphenyl (42% Chlorine) (PCB)....... 53469-21-9 ............ 1 X
Chlorodiphenyl (54% Chlorine) (PCB)....... 11097-69-1 ............ 0.5 X
1-Chloro-2,3-epoxypropane; see
Epichlorohydrin.
2-Chloroethanol; see Ethylene
chlorohydrin.
Chloroethylene; see Vinyl chloride.
Chloroform (Trichloromethane)............. 67-66-3 (C)50 (C)240
bis(Chloromethyl) ether; see 1910.1008.... 542-88-1
Chloromethyl methyl ether; see 1910.1006.. 107-30-2
1-Chloro-1-nitropropane................... 600-25-9 20 100
Chloropicrin.............................. 76-06-2 0.1 0.7
beta-Chloroprene.......................... 126-99-8 25 90 X
2-Chloro-6-(trichloromethyl) pyridine..... 1929-82-4
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Chromium (II) compounds.
(as Cr)............................... 7440-47-3 ............ 0.5
Chromium (III) compounds.
(as Cr)............................... 7440-47-3 ............ 0.5
Chromium (VI) compounds; See 1910.1026 \5\
Chromium metal and insol. salts (as Cr)... 7440-47-3 ............ 1
Chrysene; see Coal tar pitch volatiles.
Clopidol.................................. 2971-90-6
[[Page 11]]
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Coal dust (less than 5% SiO2), respirable .............. ............ (\3\)
fraction.
Coal dust (greater than or equal to 5% .............. ............ (\3\)
SiO2), respirable fraction.
Coal tar pitch volatiles (benzene soluble 65966-93-2 ............ 0.2
fraction), anthracene, BaP, phenanthrene,
acridine, chrysene, pyrene.
Cobalt metal, dust, and fume (as Co)...... 7440-48-4 ............ 0.1
Coke oven emissions; see 1910.1029.
Copper.................................... 7440-50-8
Fume (as Cu).......................... .............. ............ 0.1
Dusts and mists (as Cu)............... .............. ............ 1
Cotton dust \e\; see 1910.1043............ .............. ............ 1
Crag herbicide (Sesone)................... 136-78-7
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Cresol, all isomers....................... 1319-77-3 5 22 X
Crotonaldehyde............................ 123-73-9; 2 6
4170-30-3
Cumene.................................... 98-82-8 50 245 X
Cyanides (as CN).......................... (\4\) ............ 5 X
Cyclohexane............................... 110-82-7 300 1050
Cyclohexanol.............................. 108-93-0 50 200
Cyclohexanone............................. 108-94-1 50 200
Cyclohexene............................... 110-83-8 300 1015
Cyclopentadiene........................... 542-92-7 75 200
2,4-D (Dichlorophenoxyacetic acid)........ 94-75-7 ............ 10
Decaborane................................ 17702-41-9 0.05 0.3 X
Demeton (Systox).......................... 8065-48-3 ............ 0.1 X
Diacetone alcohol (4-Hydroxy-4-methyl-2- 123-42-2 50 240
pentanone).
1,2-Diaminoethane; see Ethylenediamine.
Diazomethane.............................. 334-88-3 0.2 0.4
Diborane.................................. 19287-45-7 0.1 0.1
1,2-Dibromo-3-chloropropane (DBCP); see 96-12-8
1910.1044.
1,2-Dibromoethane; see Ethylene dibromide.
Dibutyl phosphate......................... 107-66-4 1 5
Dibutyl phthalate......................... 84-74-2 ............ 5
o-Dichlorobenzene......................... 95-50-1 (C)50 (C)300
p-Dichlorobenzene......................... 106-46-7 75 450
3,'-Dichlorobenzidine; see 1910.1007...... 91-94-1
Dichlorodifluoromethane................... 75-71-8 1000 4950
1,3-Dichloro-5,5-dimethyl hydantoin....... 118-52-5 ............ 0.2
Dichlorodiphenyltrichloroethane (DDT)..... 50-29-3 ............ 1 X
1,1-Dichloroethane........................ 75-34-3 100 400
1,2-Dichloroethane; see Ethylene
dichloride.
1,2-Dichloroethylene...................... 540-59-0 200 790
Dichloroethyl ether....................... 111-44-4 (C)15 (C)90 X
Dichloromethane; see Methylene chloride.
Dichloromonofluoromethane................. 75-43-4 1000 4200
1,1-Dichloro-1-nitroethane................ 594-72-9 (C)10 (C)60
1,2-Dichloropropane; see Propylene
dichloride.
Dichlorotetrafluoroethane................. 76-14-2 1000 7000
Dichlorvos (DDVP)......................... 62-73-7 ............ 1 X
Dicyclopentadienyl iron................... 102-54-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Dieldrin.................................. 60-57-1 ............ 0.25 X
Diethylamine.............................. 109-89-7 25 75
2-Diethylaminoethanol..................... 100-37-8 10 50 X
Diethyl ether; see Ethyl ether.
Difluorodibromomethane.................... 75-61-6 100 860
Diglycidyl ether (DGE).................... 2238-07-5 (C)0.5 (C)2.8
Dihydroxybenzene; see Hydroquinone.
Diisobutyl ketone......................... 108-83-8 50 290
Diisopropylamine.......................... 108-18-9 5 20 X
4-Dimethylaminoazobenzene; see 1910.1015.. 60-11-7
Dimethoxymethane; see Methylal.
Dimethyl acetamide........................ 127-19-5 10 35 X
Dimethylamine............................. 124-40-3 10 18
Dimethylaminobenzene; see Xylidine........
Dimethylaniline (N,N-Dimethylaniline)..... 121-69-7 5 25 X
Dimethylbenzene; see Xylene.
[[Page 12]]
Dimethyl-1,2-dibromo-2,2-dichloroethyl 300-76-5 ............ 3
phosphate.
Dimethylformamide......................... 68-12-2 10 30 X
2,6-Dimethyl-4-heptanone; see Diisobutyl
ketone.
1,1-Dimethylhydrazine..................... 57-14-7 0.5 1 X
Dimethylphthalate......................... 131-11-3 ............ 5
Dimethyl sulfate.......................... 77-78-1 1 5 X
Dinitrobenzene (all isomers).............. .............. ............ 1 X
(ortho)............................... 528-29-0
(meta)................................ 99-65-0
(para)................................ 100-25-4
Dinitro-o-cresol.......................... 534-52-1 ............ 0.2 X
Dinitrotoluene............................ 25321-14-6 ............ 1.5 X
Dioxane (Diethylene dioxide).............. 123-91-1 100 360 X
Diphenyl (Biphenyl)....................... 92-52-4 0.2 1
Diphenylmethane diisocyanate; see
Methylene bisphenyl isocyanate.
Dipropylene glycol methyl ether........... 34590-94-8 100 600 X
Di-sec octyl phthalate (Di-(2-ethylhexyl) 117-81-7 ............ 5
phthalate).
Emery..................................... 12415-34-8
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Endrin.................................... 72-20-8 ............ 0.1 X
Epichlorohydrin........................... 106-89-8 5 19 X
EPN....................................... 2104-64-5 ............ 0.5 X
1,2-Epoxypropane; see Propylene oxide.
2,3-Epoxy-1-propanol; see Glycidol.
Ethanethiol; see Ethyl mercaptan.
Ethanolamine.............................. 141-43-5 3 6
2-Ethoxyethanol (Cellosolve).............. 110-80-5 200 740 X
2-Ethoxyethyl acetate (Cellosolve acetate) 111-15-9 100 540 X
Ethyl acetate............................. 141-78-6 400 1400
Ethyl acrylate............................ 140-88-5 25 100 X
Ethyl alcohol (Ethanol)................... 64-17-5 1000 1900
Ethylamine................................ 75-04-7 10 18
Ethyl amyl ketone (5-Methyl-3-heptanone).. 541-85-5 25 130
Ethyl benzene............................. 100-41-4 100 435
Ethyl bromide............................. 74-96-4 200 890
Ethyl butyl ketone (3-Heptanone).......... 106-35-4 50 230
Ethyl chloride............................ 75-00-3 1000 2600
Ethyl ether............................... 60-29-7 400 1200
Ethyl formate............................. 109-94-4 100 300
Ethyl mercaptan........................... 75-08-1 (C)10 (C)25
Ethyl silicate............................ 78-10-4 100 850
Ethylene chlorohydrin..................... 107-07-3 5 16 X
Ethylenediamine........................... 107-15-3 10 25
Ethylene dibromide........................ 106-93-4 ............ (\2\)
Ethylene dichloride (1,2-Dichloroethane).. 107-06-2 ............ (\2\)
Ethylene glycol dinitrate................. 628-96-6 (C)0.2 (C)1 X
Ethylene glycol methyl acetate; see Methyl
cellosolve acetate.
Ethyleneimine; see 1910.1012.............. 151-56-4
Ethylene oxide; see 1910.1047............. 75-21-8
Ethylidene chloride; see 1,1-
Dichloroethane.
N-Ethylmorpholine......................... 100-74-3 20 94 X
Ferbam.................................... 14484-64-1
Total dust............................ .............. ............ 15
Ferrovanadium dust........................ 12604-58-9 ............ 1
Fluorides (as F).......................... (\4\) ............ 2.5
Fluorine.................................. 7782-41-4 0.1 0.2
Fluorotrichloromethane 75-69-4 1000 5600
(Trichlorofluoromethane).
Formaldehyde; see 1910.1048............... 50-00-0
Formic acid............................... 64-18-6 5 9
Furfural.................................. 98-01-1 5 20 X
Furfuryl alcohol.......................... 98-00-0 50 200
Grain dust (oat, wheat, barley)........... .............. ............ 10
Glycerin (mist)........................... 56-81-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Glycidol.................................. 556-52-5 50 150
Glycol monoethyl ether; see 2-
Ethoxyethanol.
Graphite, natural, respirable dust........ 7782-42-5 ............ (\3\)
Graphite, synthetic.......................
[[Page 13]]
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Guthion; see Azinphos methyl.
Gypsum.................................... 13397-24-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Hafnium................................... 7440-58-6 ............ 0.5
Heptachlor................................ 76-44-8 ............ 0.5 X
Heptane (n-Heptane)....................... 142-82-5 500 2000
Hexachloroethane.......................... 67-72-1 1 10 X
Hexachloronaphthalene..................... 1335-87-1 ............ 0.2 X
n-Hexane.................................. 110-54-3 500 1800
2-Hexanone (Methyl n-butyl ketone)........ 591-78-6 100 410
Hexone (Methyl isobutyl ketone)........... 108-10-1 100 410
sec-Hexyl acetate......................... 108-84-9 50 300
Hydrazine................................. 302-01-2 1 1.3 X
Hydrogen bromide.......................... 10035-10-6 3 10
Hydrogen chloride......................... 7647-01-0 (C)5 (C)7
Hydrogen cyanide.......................... 74-90-8 10 11 X
Hydrogen fluoride (as F).................. 7664-39-3 ............ (\2\)
Hydrogen peroxide......................... 7722-84-1 1 1.4
Hydrogen selenide (as Se)................. 7783-07-5 0.05 0.2
Hydrogen sulfide.......................... 7783-06-4 ............ (\2\)
Hydroquinone.............................. 123-31-9 ............ 2
Iodine.................................... 7553-56-2 (C)0.1 (C)1
Iron oxide fume........................... 1309-37-1 ............ 10
Isoamyl acetate........................... 123-92-2 100 525
Isoamyl alcohol (primary and secondary)... 123-51-3 100 360
Isobutyl acetate.......................... 110-19-0 150 700
Isobutyl alcohol.......................... 78-83-1 100 300
Isophorone................................ 78-59-1 25 140
Isopropyl acetate......................... 108-21-4 250 950
Isopropyl alcohol......................... 67-63-0 400 980
Isopropylamine............................ 75-31-0 5 12
Isopropyl ether........................... 108-20-3 500 2100
Isopropyl glycidyl ether (IGE)............ 4016-14-2 50 240
Kaolin.................................... 1332-58-7
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Ketene.................................... 463-51-4 0.5 0.9
Lead, inorganic (as Pb); see 1910.1025.... 7439-92-1
Limestone................................. 1317-65-3
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Lindane................................... 58-89-9 ............ 0.5 X
Lithium hydride........................... 7580-67-8 ............ 0.025
L.P.G. (Liquefied petroleum gas).......... 68476-85-7 1000 1800
Magnesite................................. 546-93-0
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Magnesium oxide fume...................... 1309-48-4
Total particulate..................... .............. ............ 15
Malathion................................. 121-75-5
Total dust............................ .............. ............ 15 X
Maleic anhydride.......................... 108-31-6 0.25 1
Manganese compounds (as Mn)............... 7439-96-5 ............ (C)5
Manganese fume (as Mn).................... 7439-96-5 ............ (C)5
Marble.................................... 1317-65-3
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Mercury (aryl and inorganic) (as Hg)...... 7439-97-6 ............ (\2\)
Mercury (organo) alkyl compounds (as Hg).. 7439-97-6 ............ (\2\)
Mercury (vapor) (as Hg)................... 7439-97-6 ............ (\2\)
Mesityl oxide............................. 141-79-7 25 100
Methanethiol; see Methyl mercaptan.
Methoxychlor.............................. 72-43-5
Total dust............................ .............. ............ 15
2-Methoxyethanol (Methyl cellosolve)...... 109-86-4 25 80 X
2-Methoxyethyl acetate (Methyl cellosolve 110-49-6 25 120 X
acetate).
Methyl acetate............................ 79-20-9 200 610
Methyl acetylene (Propyne)................ 74-99-7 1000 1650
Methyl acetylene-propadiene mixture (MAPP) .............. 1000 1800
[[Page 14]]
Methyl acrylate........................... 96-33-3 10 35 X
Methylal (Dimethoxy-methane).............. 109-87-5 1000 3100
Methyl alcohol............................ 67-56-1 200 260
Methylamine............................... 74-89-5 10 12
Methyl amyl alcohol; see Methyl isobutyl
carbinol.
Methyl n-amyl ketone...................... 110-43-0 100 465
Methyl bromide............................ 74-83-9 (C)20 (C)80 X
Methyl butyl ketone; see 2-Hexanone.
Methyl cellosolve; see 2-Methoxyethanol.
Methyl cellosolve acetate; see 2-
Methoxyethyl acetate.
Methyl chloride........................... 74-87-3 ............ (\2\)
Methyl chloroform (1,1,1-Trichloroethane). 71-55-6 350 1900
Methylcyclohexane......................... 108-87-2 500 2000
Methylcyclohexanol........................ 25639-42-3 100 470
o-Methylcyclohexanone..................... 583-60-8 100 460 X
Methylene chloride........................ 75-09-2 ............ (\2\)
Methyl ethyl ketone (MEK); see 2-Butanone.
Methyl formate............................ 107-31-3 100 250
Methyl hydrazine (Monomethyl hydrazine)... 60-34-4 (C)0.2 (C)0.35 X
Methyl iodide............................. 74-88-4 5 28 X
Methyl isoamyl ketone..................... 110-12-3 100 475
Methyl isobutyl carbinol.................. 108-11-2 25 100 X
Methyl isobutyl ketone; see Hexone.
Methyl isocyanate......................... 624-83-9 0.02 0.05 X
Methyl mercaptan.......................... 74-93-1 (C)10 (C)20
Methyl methacrylate....................... 80-62-6 100 410
Methyl propyl ketone; see 2-Pentanone.
alpha-Methyl styrene...................... 98-83-9 (C)100 (C)480
Methylene bisphenyl isocyanate (MDI)...... 101-68-8 (C)0.02 (C)0.2
Mica; see Silicates.
Molybdenum (as Mo)........................ 7439-98-7
Soluble compounds..................... .............. ............ 5
Insoluble compounds.
Total dust......................... .............. ............ 15
Monomethyl aniline........................ 100-61-8 2 9 X
Monomethyl hydrazine; see Methyl
hydrazine.
Morpholine................................ 110-91-8 20 70 X
Naphtha (Coal tar)........................ 8030-30-6 100 400
Naphthalene............................... 91-20-3 10 50
alpha-Naphthylamine; see 1910.1004........ 134-32-7
beta-Naphthylamine; see 1910.1009......... 91-59-8
Nickel carbonyl (as Ni)................... 13463-39-3 0.001 0.007
Nickel, metal and insoluble compounds (as 7440-02-0 ............ 1
Ni).
Nickel, soluble compounds (as Ni)......... 7440-02-0 ............ 1
Nicotine.................................. 54-11-5 ............ 0.5 X
Nitric acid............................... 7697-37-2 2 5
Nitric oxide.............................. 10102-43-9 25 30
p-Nitroaniline............................ 100-01-6 1 6 X
Nitrobenzene.............................. 98-95-3 1 5 X
p-Nitrochlorobenzene...................... 100-00-5 ............ 1 X
4-Nitrodiphenyl; see 1910.1003............ 92-93-3
Nitroethane............................... 79-24-3 100 310
Nitrogen dioxide.......................... 10102-44-0 (C)5 (C)9
Nitrogen trifluoride...................... 7783-54-2 10 29
Nitroglycerin............................. 55-63-0 (C)0.2 (C)2 X
Nitromethane.............................. 75-52-5 100 250
1-Nitropropane............................ 108-03-2 25 90
2-Nitropropane............................ 79-46-9 25 90
N-Nitrosodimethylamine; see 1910.1016.
Nitrotoluene (all isomers)................ .............. 5 30 X
o-isomer.............................. 88-72-2
m-isomer.............................. 99-08-1
p-isomer.............................. 99-99-0
Nitrotrichloromethane; see Chloropicrin.
Octachloronaphthalene..................... 2234-13-1 ............ 0.1 X
Octane.................................... 111-65-9 500 2350
Oil mist, mineral......................... 8012-95-1 ............ 5
Osmium tetroxide (as Os).................. 20816-12-0 ............ 0.002
Oxalic acid............................... 144-62-7 ............ 1
Oxygen difluoride......................... 7783-41-7 0.05 0.1
Ozone..................................... 10028-15-6 0.1 0.2
[[Page 15]]
Paraquat, respirable dust................. 4685-14-7; ............ 0.5 X
1910-42-5;
2074-50-2
Parathion................................. 56-38-2 ............ 0.1 X
Particulates not otherwise regulated
(PNOR) \f\.
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
PCB; see Chlorodiphenyl (42% and 54%
chlorine).
Pentaborane............................... 19624-22-7 0.005 0.01
Pentachloronaphthalene.................... 1321-64-8 ............ 0.5 X
Pentachlorophenol......................... 87-86-5 ............ 0.5 X
Pentaerythritol........................... 115-77-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Pentane................................... 109-66-0 1000 2950
2-Pentanone (Methyl propyl ketone)........ 107-87-9 200 700
Perchloroethylene (Tetrachloroethylene)... 127-18-4 ............ (\2\)
Perchloromethyl mercaptan................. 594-42-3 0.1 0.8
Perchloryl fluoride....................... 7616-94-6 3 13.5
Petroleum distillates (Naphtha) (Rubber .............. 500 2000
Solvent).
Phenol.................................... 108-95-2 5 19 X
p-Phenylene diamine....................... 106-50-3 ............ 0.1 X
Phenyl ether, vapor....................... 101-84-8 1 7
Phenyl ether-biphenyl mixture, vapor...... .............. 1 7
Phenylethylene; see Styrene.
Phenyl glycidyl ether (PGE)............... 122-60-1 10 60
Phenylhydrazine........................... 100-63-0 5 22 X
Phosdrin (Mevinphos)...................... 7786-34-7 ............ 0.1 X
Phosgene (Carbonyl chloride).............. 75-44-5 0.1 0.4
Phosphine................................. 7803-51-2 0.3 0.4
Phosphoric acid........................... 7664-38-2 ............ 1
Phosphorus (yellow)....................... 7723-14-0 ............ 0.1
Phosphorus pentachloride.................. 10026-13-8 ............ 1
Phosphorus pentasulfide................... 1314-80-3 ............ 1
Phosphorus trichloride.................... 7719-12-2 0.5 3
Phthalic anhydride........................ 85-44-9 2 12
Picloram.................................. 1918-02-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Picric acid............................... 88-89-1 ............ 0.1 X
Pindone (2-Pivalyl-1,3-indandione)........ 83-26-1 ............ 0.1
Plaster of Paris.......................... 26499-65-0
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Platinum (as Pt).......................... 7440-06-4
Metal.................................
Soluble salts......................... .............. ............ 0.002
Portland cement........................... 65997-15-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Propane................................... 74-98-6 1000 1800
beta-Propriolactone; see 1910.1013........ 57-57-8
n-Propyl acetate.......................... 109-60-4 200 840
n-Propyl alcohol.......................... 71-23-8 200 500
n-Propyl nitrate.......................... 627-13-4 25 110
Propylene dichloride...................... 78-87-5 75 350
Propylene imine........................... 75-55-8 2 5 X
Propylene oxide........................... 75-56-9 100 240
Propyne; see Methyl acetylene.
Pyrethrum................................. 8003-34-7 ............ 5
Pyridine.................................. 110-86-1 5 15
Quinone................................... 106-51-4 0.1 0.4
RDX; see Cyclonite.
Rhodium (as Rh), metal fume and insoluble 7440-16-6 ............ 0.1
compounds.
Rhodium (as Rh), soluble compounds........ 7440-16-6 ............ 0.001
Ronnel.................................... 299-84-3 ............ 15
Rotenone.................................. 83-79-4 ............ 5
Rouge.....................................
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Selenium compounds (as Se)................ 7782-49-2 ............ 0.2
Selenium hexafluoride (as Se)............. 7783-79-1 0.05 0.4
[[Page 16]]
Silica, amorphous, precipitated and gel... 112926-00-8 ............ (\3\)
Silica, amorphous, diatomaceous earth, 61790-53-2 ............ (\3\)
containing less than 1% crystalline
silica.
Silica, crystalline cristobalite, 14464-46-1 ............ (\3\)
respirable dust.
Silica, crystalline quartz, respirable 14808-60-7 ............ (\3\)
dust.
Silica, crystalline tripoli (as quartz), 1317-95-9 ............ (\3\)
respirable dust.
Silica, crystalline tridymite, respirable 15468-32-3 ............ (\3\)
dust.
Silica, fused, respirable dust............ 60676-86-0 ............ (\3\)
Silicates (less than 1% crystalline
silica).
Mica (respirable dust)................ 12001-26-2 ............ (\3\)
Soapstone, total dust................. .............. ............ (\3\)
Soapstone, respirable dust............ .............. ............ (\3\)
Talc (containing asbestos); use .............. ............ (\3\)
asbestos limit; see 29 CFR 1910.1001.
Talc (containing no asbestos), 14807-96-6 ............ (\3\)
respirable dust.
Tremolite, asbestiform; see 1910.1001.
Silicon................................... 7440-21-3
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Silicon carbide........................... 409-21-2
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Silver, metal and soluble compounds (as 7440-22-4 ............ 0.01
Ag).
Soapstone; see Silicates.
Sodium fluoroacetate...................... 62-74-8 ............ 0.05 X
Sodium hydroxide.......................... 1310-73-2 ............ 2
Starch.................................... 9005-25-8
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Stibine................................... 7803-52-3 0.1 0.5
Stoddard solvent.......................... 8052-41-3 500 2900
Strychnine................................ 57-24-9 ............ 0.15
Styrene................................... 100-42-5 ............ (\2\)
Sucrose................................... 57-50-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Sulfur dioxide............................ 7446-09-5 5 13
Sulfur hexafluoride....................... 2551-62-4 1000 6000
Sulfuric acid............................. 7664-93-9 ............ 1
Sulfur monochloride....................... 10025-67-9 1 6
Sulfur pentafluoride...................... 5714-22-7 0.025 0.25
Sulfuryl fluoride......................... 2699-79-8 5 20
Systox; see Demeton.
2,4,5-T (2,4,5-trichlorophenoxyacetic 93-76-5 ............ 10
acid).
Talc; see Silicates.
Tantalum, metal and oxide dust............ 7440-25-7 ............ 5
TEDP (Sulfotep)........................... 3689-24-5 ............ 0.2 X
Tellurium and compounds (as Te)........... 13494-80-9 ............ 0.1
Tellurium hexafluoride (as Te)............ 7783-80-4 0.02 0.2
Temephos.................................. 3383-96-8
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
TEPP (Tetraethyl pyrophosphate)........... 107-49-3 ............ 0.05 X
Terphenyls................................ 26140-60-3 (C)1 (C)9
1,1,1,2-Tetrachloro-2,2-difluoroethane.... 76-11-9 500 4170
1,1,2,2-Tetrachloro-1,2-difluoroethane.... 76-12-0 500 4170
1,1,2,2-Tetrachloroethane................. 79-34-5 5 35 X
Tetrachloroethylene; see
Perchloroethylene.
Tetrachloromethane; see Carbon
tetrachloride.
Tetrachloronaphthalene.................... 1335-88-2 ............ 2 X
Tetraethyl lead (as Pb)................... 78-00-2 ............ 0.075 X
Tetrahydrofuran........................... 109-99-9 200 590
Tetramethyl lead (as Pb).................. 75-74-1 ............ 0.075 X
Tetramethyl succinonitrile................ 3333-52-6 0.5 3 X
Tetranitromethane......................... 509-14-8 1 8
Tetryl (2,4,6- 479-45-8 ............ 1.5 X
Trinitrophenylmethylnitramine).
Thallium, soluble compounds (as Tl)....... 7440-28-0 ............ 0.1 X
4,4'-Thiobis (6-tert, Butyl-m-cresol)..... 96-69-5
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Thiram.................................... 137-26-8 ............ 5
Tin, inorganic compounds (except oxides) 7440-31-5 ............ 2
(as Sn).
[[Page 17]]
Tin, organic compounds (as Sn)............ 7440-31-5 ............ 0.1
Titanium dioxide.......................... 13463-67-7
Total dust............................ .............. ............ 15
Toluene................................... 108-88-3 ............ (\2\)
Toluene-2,4-diisocyanate (TDI)............ 584-84-9 (C)0.02 (C)0.14
o-Toluidine............................... 95-53-4 5 22 X
Toxaphene; see Chlorinated camphene.
Tremolite; see Silicates.
Tributyl phosphate........................ 126-73-8 ............ 5
1,1,1-Trichloroethane; see Methyl
chloroform.
1,1,2-Trichloroethane..................... 79-00-5 10 45 X
Trichloroethylene......................... 79-01-6 ............ (\2\)
Trichloromethane; see Chloroform.
Trichloronaphthalene...................... 1321-65-9 ............ 5 X
1,2,3-Trichloropropane.................... 96-18-4 50 300
1,1,2-Trichloro-1,2,2-trifluoroethane..... 76-13-1 1000 7600
Triethylamine............................. 121-44-8 25 100
Trifluorobromomethane..................... 75-63-8 1000 6100
2,4,6-Trinitrophenol; see Picric acid.
2,4,6-Trinitrophenylmethylnitramine; see
Tetryl.
2,4,6-Trinitrotoluene (TNT)............... 118-96-7 ............ 1.5 X
Triorthocresyl phosphate.................. 78-30-8 ............ 0.1
Triphenyl phosphate....................... 115-86-6 ............ 3
Turpentine................................ 8006-64-2 100 560
Uranium (as U)............................ 7440-61-1
Soluble compounds..................... .............. ............ 0.05
Insoluble compounds................... .............. ............ 0.25
Vanadium.................................. 1314-62-1
Respirable dust (as V2 O5)............ .............. ............ (C)0.5
Fume (as V2 O5)....................... .............. ............ (C)0.1
Vegetable oil mist........................
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Vinyl benzene; see Styrene.
Vinyl chloride; see 1910.1017............. 75-01-4
Vinyl cyanide; see Acrylonitrile.
Vinyl toluene............................. 25013-15-4 100 480
Warfarin.................................. 81-81-2 ............ 0.1
Xylenes (o-, m-, p-isomers)............... 1330-20-7 100 435
Xylidine.................................. 1300-73-8 5 25 X
Yttrium................................... 7440-65-5 ............ 1
Zinc chloride fume........................ 7646-85-7 ............ 1
Zinc oxide fume........................... 1314-13-2 ............ 5
Zinc oxide................................ 1314-13-2
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Zinc stearate............................. 557-05-1
Total dust............................ .............. ............ 15
Respirable fraction................... .............. ............ 5
Zirconium compounds (as Zr)............... 7440-67-7 ............ 5
----------------------------------------------------------------------------------------------------------------
\1\ The PELs are 8-hour TWAs unless otherwise noted; a (C) designation denotes a ceiling limit. They are to be
determined from breathing-zone air samples.
(a) Parts of vapor or gas per million parts of contaminated air by volume at 25 [deg]C and 760 torr.
(b) Milligrams of substance per cubic meter of air. When entry is in this column only, the value is exact; when
listed with a ppm entry, it is approximate.
(c) The CAS number is for information only. Enforcement is based on the substance name. For an entry covering
more than one metal compound, measured as the metal, the CAS number for the metal is given--not CAS numbers
for the individual compounds.
(d) The final benzene standard in 1910.1028 applies to all occupational exposures to benzene except in some
circumstances the distribution and sale of fuels, sealed containers and pipelines, coke production, oil and
gas drilling and production, natural gas processing, and the percentage exclusion for liquid mixtures; for the
excepted subsegments, the benzene limits in Table Z-2 apply. See 1910.1028 for specific circumstances.
(e) This 8-hour TWA applies to respirable dust as measured by a vertical elutriator cotton dust sampler or
equivalent instrument. The time-weighted average applies to the cottom waste processing operations of waste
recycling (sorting, blending, cleaning and willowing) and garnetting. See also 1910.1043 for cotton dust
limits applicable to other sectors.
(f) All inert or nuisance dusts, whether mineral, inorganic, or organic, not listed specifically by substance
name are covered by the Particulates Not Otherwise Regulated (PNOR) limit which is the same as the inert or
nuisance dust limit of Table Z-3.
\2\ See Table Z-2.
\3\ See Table Z-3.
\4\ Varies with compound.
\5\ See Table Z-2 for the exposure limit for any operations or sectors where the exposure limit in Sec.
1910.1026 is stayed or is otherwise not in effect.
\6\ If the exposure limit inSec. 1910.1026 is stayed or is otherwise not in effect, the exposure limit is a
ceiling of 0.1 mg/m\3\.
[[Page 18]]
Table Z-2
----------------------------------------------------------------------------------------------------------------
Acceptable maximum peak above the
acceptable ceiling concentration for an
Substance 8-hour time Acceptable ceiling 8-hr shift
weighted average concentration ----------------------------------------
Concentration Maximum duration
----------------------------------------------------------------------------------------------------------------
Benzene \a\ (Z37.40-1969)...... 10 ppm............ 25 ppm............ 50 ppm............ 10 minutes.
Beryllium and beryllium 2 [micro]g/m\3\... 5 [micro]g/m\3\... 25 [micro]g/m\3\.. 30 minutes.
compounds (Z37.29-1970).
Cadmium fume \b\ (Z37.5-1970).. 0.1 mg/m\3\....... 0.3 mg/m\3\.......
Cadmium dust \b\ (Z37.5-1970).. 0.2 mg/m\3\....... 0.6 mg/m\3\.......
Carbon disulfide (Z37.3-1968).. 20 ppm............ 30 ppm............ 100 ppm........... 30 minutes.
Carbon tetrachloride (Z37.17- 10 ppm............ 25 ppm............ 200 ppm........... 5 min. in any 4
1967). hrs.
Chromic acid and chromates .................. 1 mg/10m\3\.......
(Z37.7-1971) (as CrO3)\c\.
Ethylene dibromide (Z37.31- 20 ppm............ 30 ppm............ 50 ppm............ 5 minutes.
1970).
Ethylene dichloride (Z37.21- 50 ppm............ 100 ppm........... 200 ppm........... 5 min. in any 3
1969). hrs.
Fluoride as dust (Z37.28-1969). 2.5 mg/m\3\.......
Formaldehyde; see 1910.1048....
Hydrogen fluoride (Z37.28-1969) 3 ppm.............
Hydrogen sulfide (Z37.2-1966).. .................. 20 ppm............ 50 ppm............ 10 mins. once, only
if no other meas.
exp. occurs.
Mercury (Z37.8-1971)........... .................. 1 mg/10m\3\.......
Methyl chloride (Z37.18-1969).. 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 3
hrs.
Methylene Chloride: See Sec.
1919.52..
Organo (alkyl) mercury (Z37.30- 0.01 mg/m\3\...... 0.04 mg/m\3\......
1969).
Styrene (Z37.15-1969).......... 100 ppm........... 200 ppm........... 600 ppm........... 5 mins. in any 3
hrs.
Tetrachloroethylene (Z37.22- 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 3
1967). hrs.
Toluene (Z37.12-1967).......... 200 ppm........... 300 ppm........... 500 ppm........... 10 minutes.
Trichloroethylene (Z37.19-1967) 100 ppm........... 200 ppm........... 300 ppm........... 5 mins. in any 2
hrs.
----------------------------------------------------------------------------------------------------------------
\a\ This standard applies to the industry segments exempt from the 1 ppm 8-hour TWA and 5 ppm STEL of the
benzene standard at 1910.1028.
\b\ This standard applies to any operations or sectors for which the Cadmium standard, 1910.1027, is stayed or
otherwise not in effect.
\c\ This standard applies to any operations or sectors for which the exposure limit in the Chromium (VI)
standard,Sec. 1910.1026, is stayed or is otherwise not in effect.
Table Z-3--Mineral Dusts
------------------------------------------------------------------------
Substance mppcf \a\ mg/m\3\
------------------------------------------------------------------------
Silica:
Crystalline
250 \b\ 10 mg/m\3\
\e\
Quartz (Respirable)....................... ---------- ----------
%SiO2+5 % SiO2 + 2
........... 30 mg/m\3\
Quartz (Total Dust)....................... ........... ----------
% SiO2 + 2
Cristobalite: Use \1/2\ the value calculated
from the count or mass formulae for quartz
Tridymite: Use \1/2\ the value calculated
from the formulae for quartz
........... 80 mg/m\3\
Amorphous, including natural diatomaceous 20 ----------
earth........................................ %SiO2
Silicates (less than 1% crystalline silica):
Mica........................................ 20
Soapstone................................... 20
Talc (not containing asbestos).............. 20 \c\
Talc (containing asbestos) Use asbestos
limit......................................
Tremolite, asbestiform (see 29 CFR
1910.1001).................................
Portland cement............................. 50
Graphite (Natural)............................ 15
Coal Dust:
Respirable fraction less than 5% SiO2....... ........... 2.4 mg/
m\3\ \e\
[[Page 19]]
........... 10 mg/m\3\
\e\
Respirable fraction greater than 5% SiO2.... ........... ----------
%SiO2+2
Inert or Nuisance Dust: \d\
Respirable fraction......................... 15 5 mg/m\3\
Total dust.................................. 50 15 mg/m\3\
------------------------------------------------------------------------
Note--Conversion factors - mppcf x 35.3 = million particles per cubic
meter = particles per c.c.
\a\ Millions of particles per cubic foot of air, based on impinger
samples counted by light-field techniques.
\b\ The percentage of crystalline silica in the formula is the amount
determined from airborne samples, except in those instances in which
other methods have been shown to be applicable.
\c\ Containing less than 1% quartz; if 1% quartz or more, use quartz
limit.
\d\ All inert or nuisance dusts, whether mineral, inorganic, or organic,
not listed specifically by substance name are covered by this limit,
which is the same as the Particulates Not Otherwise Regulated (PNOR)
limit in Table Z-1.
\e\ Both concentration and percent quartz for the application of this
limit are to be determined from the fraction passing a size-selector
with the following characteristics:
------------------------------------------------------------------------
Percent passing
Aerodynamic diameter (unit density sphere) selector
------------------------------------------------------------------------
2.................................................... 90
2.5.................................................. 75
3.5.................................................. 50
5.0.................................................. 25
10................................................... 0
------------------------------------------------------------------------
The measurements under this note refer to the use of an AEC (now NRC)
instrument. The respirable fraction of coal dust is determined with an
MRE; the figure corresponding to that of 2.4 mg/m\3\ in the table for
coal dust is 4.5 mg/m\3K\.
[58 FR 35340, June 30. 1993; 58 FR 40191, July 27, 1993, as amended at
61 FR 56831, Nov. 4, 1996; 62 FR 1600, Jan. 10, 1997; 62 FR 42018, Aug.
4, 1997; 71 FR 10373, Feb. 28, 2006; 71 FR 16673, Apr. 3, 2006; 71 FR
36008, June 23, 2006]
Sec. 1910.1001 Asbestos.
(a) Scope and application. (1) This section applies to all
occupational exposures to asbestos in all industries covered by the
Occupational Safety and Health Act, except as provided in paragraph
(a)(2) and (3) of this section.
(2) This section does not apply to construction work as defined in
29 CFR 1910.12(b). (Exposure to asbestos in construction work is covered
by 29 CFR 1926.1101).
(3) This section does not apply to ship repairing, shipbuilding and
shipbreaking employments and related employments as defined in 29 CFR
1915.4. (Exposure to asbestos in these employments is covered by 29 CFR
1915.1001).
(b) Definitions. Asbestos includes chrysotile, amosite, crocidolite,
tremolite asbestos, anthophyllite asbestos, actinolite asbestos, and any
of these minerals that have been chemically treated and/or altered.
Asbestos-containing material (ACM) means any material containing
more than 1% asbestos.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and
required by work duties to be present in regulated areas.
Building/facility owner is the legal entity, including a lessee,
which exercises control over management and record keeping functions
relating to a building and/or facility in which activities covered by
this standard take place.
Certified industrial hygienist (CIH) means one certified in the
practice of industrial hygiene by the American Board of Industrial
Hygiene.
Director means the Director of the National Institute for
Occupational Safety and Health, U.S. Department of Health and Human
Services, or designee.
Employee exposure means that exposure to airborne asbestos that
would occur if the employee were not using respiratory protective
equipment.
Fiber means a particulate form of asbestos 5 micrometers or
longer,with a
[[Page 20]]
length-to-diameter ratio of at least 3 to 1.
High-efficiency particulate air (HEPA) filter means a filter capable
of trapping and retaining at least 99.97 percent of 0.3 micrometer
diameter mono-disperse particles.
Homogeneous area means an area of surfacing material or thermal
system insulation that is uniform in color and texture.
Industrial hygienist means a professional qualified by education,
training, and experience to anticipate, recognize, evaluate and develop
controls for occupational health hazards.
PACM means ``presumed asbestos containing material.''
Presumed asbestos containing material means thermal system
insulation and surfacing material found in buildings constructed no
later than 1980. The designation of a material as ``PACM'' may be
rebutted pursuant to paragraph (j)(8) of this section.
Regulated area means an area established by the employer to
demarcate areas where airborne concentrations of asbestos exceed, or
there is a reasonable possibility they may exceed, the permissible
exposure limits.
Surfacing ACM means surfacing material which contains more than 1%
asbestos.
Surfacing material means material that is sprayed, troweled-on or
otherwise applied to surfaces (such as acoustical plaster on ceilings
and fireproofing materials on structural members, or other materials on
surfaces for acoustical, fireproofing, and other purposes).
Thermal System Insulation (TSI) means ACM applied to pipes,
fittings, boilers, breeching, tanks, ducts or other structural
components to prevent heat loss or gain.
Thermal System Insulation ACM means thermal system insulation which
contains more than 1% asbestos.
(c) Permissible exposure limit (PELS)--(1) Time-weighted average
limit (TWA). The employer shall ensure that no employee is exposed to an
airborne concentration of asbestos in excess of 0.1 fiber per cubic
centimeter of air as an eight (8)-hour time-weighted average (TWA) as
determined by the method prescribed in appendix A to this section, or by
an equivalent method.
(2) Excursion limit. The employer shall ensure that no employee is
exposed to an airborne concentration of asbestos in excess of 1.0 fiber
per cubic centimeter of air (1 f/cc) as averaged over a sampling period
of thirty (30) minutes as determined by the method prescribed in
appendix A to this section, or by an equivalent method.
(d) Exposure monitoring--(1) General. (i) Determinations of employee
exposure shall be made from breathing zone air samples that are
representative of the 8-hour TWA and 30-minute short-term exposures of
each employee.
(ii) Representative 8-hour TWA employee exposures shall be
determined on the basis of one or more samples representing full-shift
exposures for each shift for each employee in each job classification in
each work area. Representative 30-minute short-term employee exposures
shall be determined on the basis of one or more samples representing 30
minute exposures associated with operations that are most likely to
produce exposures above the excursion limit for each shift for each job
classification in each work area.
(2) Initial monitoring. (i) Each employer who has a workplace or
work operation covered by this standard, except as provided for in
paragraphs (d)(2)(ii) and (d)(2)(iii) of this section, shall perform
initial monitoring of employees who are, or may reasonably be expected
to be exposed to airborne concentrations at or above the TWA permissible
exposure limit and/or excursion limit.
(ii) Where the employer has monitored after March 31, 1992, for the
TWA permissible exposure limit and/or the excursion limit, and the
monitoring satisfies all other requirements of this section, the
employer may rely on such earlier monitoring results to satisfy the
requirements of paragraph (d)(2)(i) of this section.
(iii) Where the employer has relied upon objective data that
demonstrate that asbestos is not capable of being released in airborne
concentrations at or above the TWA permissible exposure limit and/or
excursion limit under the expected conditions of processing, use,
[[Page 21]]
or handling, then no initial monitoring is required.
(3) Monitoring frequency (periodic monitoring) and patterns. After
the initial determinations required by paragraph (d)(2)(i) of this
section, samples shall be of such frequency and pattern as to represent
with reasonable accuracy the levels of exposure of the employees. In no
case shall sampling be at intervals greater than six months for
employees whose exposures may reasonably be foreseen to exceed the TWA
permissible exposure limit and/or excursion limit.
(4) Changes in monitoring frequency. If either the initial or the
periodic monitoring required by paragraphs (d)(2) and (d)(3) of this
section statistically indicates that employee exposures are below the
TWA permissible exposure limit and/or excursion limit, the employer may
discontinue the monitoring for those employees whose exposures are
represented by such monitoring.
(5) Additional monitoring. Notwithstanding the provisions of
paragraphs (d)(2)(ii) and (d)(4) of this section, the employer shall
institute the exposure monitoring required under paragraphs (d)(2)(i)
and (d)(3) of this section whenever there has been a change in the
production, process, control equipment, personnel or work practices that
may result in new or additional exposures above the TWA permissible
exposure limit and/or excursion limit or when the employer has any
reason to suspect that a change may result in new or additional
exposures above the PEL and/or excursion limit.
(6) Method of monitoring. (i) All samples taken to satisfy the
monitoring requirements of paragraph (d) of this section shall be
personal samples collected following the procedures specified in
appendix A.
(ii) All samples taken to satisfy the monitoring requirements of
paragraph (d) of this section shall be evaluated using the OSHA
Reference Method (ORM) specified in appendix A of this section, or an
equivalent counting method.
(iii) If an equivalent method to the ORM is used, the employer shall
ensure that the method meets the following criteria:
(A) Replicate exposure data used to establish equivalency are
collected in side-by-side field and laboratory comparisons; and
(B) The comparison indicates that 90% of the samples collected in
the range 0.5 to 2.0 times the permissible limit have an accuracy range
of plus or minus 25 percent of the ORM results at a 95% confidence level
as demonstrated by a statistically valid protocol; and
(C) The equivalent method is documented and the results of the
comparison testing are maintained.
(iv) To satisfy the monitoring requirements of paragraph (d) of this
section, employers must use the results of monitoring analysis performed
by laboratories which have instituted quality assurance programs that
include the elements as prescribed in appendix A of this section.
(7) Employee notification of monitoring results. (i) The employer
must, within 15 working days after the receipt of the results of any
monitoring performed under this sections, notify each affected employee
of these results either individually in writing or by posting the
results in an appropriate location that is accessible to affected
employees.
(ii) The written notification required by paragraph (d)(7)(i) of
this section shall contain the corrective action being taken by the
employer to reduce employee exposure to or below the TWA and/or
excursion limit, wherever monitoring results indicated that the TWA and/
or excursion limit had been exceeded.
(e) Regulated Areas--(1) Establishment. The employer shall establish
regulated areas wherever airborne concentrations of asbestos and/or PACM
are in excess of the TWA and/or excursion limit prescribed in paragraph
(c) of this section.
(2) Demarcation. Regulated areas shall be demarcated from the rest
of the workplace in any manner that minimizes the number of persons who
will be exposed to asbestos.
(3) Access. Access to regulated areas shall be limited to authorized
persons or to persons authorized by the Act or regulations issued
pursuant thereto.
(4) Provision of respirators. Each person entering a regulated area
shall be
[[Page 22]]
supplied with and required to use a respirator, selected in accordance
with paragraph (g)(2) of this section.
(5) Prohibited activities. The employer shall ensure that employees
do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in the
regulated areas.
(f) Methods of compliance--(1) Engineering controls and work
practices. (i) The employer shall institute engineering controls and
work practices to reduce and maintain employee exposure to or below the
TWA and/or excursion limit prescribed in paragraph (c) of this section,
except to the extent that such controls are not feasible.
(ii) Wherever the feasible engineering controls and work practices
that can be instituted are not sufficient to reduce employee exposure to
or below the TWA and/or excursion limit prescribed in paragraph (c) of
this section, the employer shall use them to reduce employee exposure to
the lowest levels achievable by these controls and shall supplement them
by the use of respiratory protection that complies with the requirements
of paragraph (g) of this section.
(iii) For the following operations, wherever feasible engineering
controls and work practices that can be instituted are not sufficient to
reduce the employee exposure to or below the TWA and/or excursion limit
prescribed in paragraph (c) of this section, the employer shall use them
to reduce employee exposure to or below 0.5 fiber per cubic centimeter
of air (as an eight-hour time-weighted average) or 2.5 fibers/cc for 30
minutes (short-term exposure) and shall supplement them by the use of
any combination of respiratory protection that complies with the
requirements of paragraph (g) of this section, work practices and
feasible engineering controls that will reduce employee exposure to or
below the TWA and to or below the excursion limit permissible prescribed
in paragraph (c) of this section: Coupling cutoff in primary asbestos
cement pipe manufacturing; sanding in primary and secondary asbestos
cement sheet manufacturing; grinding in primary and secondary friction
product manufacturing; carding and spinning in dry textile processes;
and grinding and sanding in primary plastics manufacturing.
(iv) Local exhaust ventilation. Local exhaust ventilation and dust
collection systems shall be designed, constructed, installed, and
maintained in accordance with good practices such as those found in the
American National Standard Fundamentals Governing the Design and
Operation of Local Exhaust Systems, ANSI Z9.2-1979.
(v) Particular tools. All hand-operated and power-operated tools
which would produce or release fibers of asbestos, such as, but not
limited to, saws, scorers, abrasive wheels, and drills, shall be
provided with local exhaust ventilation systems which comply with
paragraph (f)(1)(iv) of this section.
(vi) Wet methods. Insofar as practicable, asbestos shall be handled,
mixed, applied, removed, cut, scored, or otherwise worked in a wet state
sufficient to prevent the emission of airborne fibers so as to expose
employees to levels in excess of the TWA and/or excursion limit,
prescribed in paragraph (c) of this section, unless the usefulness of
the product would be diminished thereby.
(vii) [Reserved]
(viii) Particular products and operations. No asbestos cement,
mortar, coating, grout, plaster, or similar material containing
asbestos, shall be removed from bags, cartons, or other containers in
which they are shipped, without being either wetted, or enclosed, or
ventilated so as to prevent effectively the release of airborne fibers.
(ix) Compressed air. Compressed air shall not be used to remove
asbestos or materials containing asbestos unless the compressed air is
used in conjunction with a ventilation system which effectively captures
the dust cloud created by the compressed air.
(x) Flooring. Sanding of asbestos-containing flooring material is
prohibited.
(2) Compliance program. (i) Where the TWA and/or excursion limit is
exceeded, the employer shall establish and implement a written program
to reduce employee exposure to or below the TWA and to or below the
excursion limit by means of engineering and work practice controls as
required by paragraph (f)(1) of this section, and by the use of
respiratory protection where
[[Page 23]]
required or permitted under this section.
(ii) Such programs shall be reviewed and updated as necessary to
reflect significant changes in the status of the employer's compliance
program.
(iii) Written programs shall be submitted upon request for
examination and copying to the Assistant Secretary, the Director,
affected employees and designated employee representatives.
(iv) The employer shall not use employee rotation as a means of
compliance with the TWA and/or excursion limit.
(3) Specific compliance methods for brake and clutch repair:
(i) Engineering controls and work practices for brake and clutch
repair and service. During automotive brake and clutch inspection,
disassembly, repair and assembly operations, the employer shall
institute engineering controls and work practices to reduce employee
exposure to materials containing asbestos using a negative pressure
enclosure/HEPA vacuum system method or low pressure/wet cleaning method,
which meets the detailed requirements set out in appendix F to this
section. The employer may also comply using an equivalent method which
follows written procedures which the employer demonstrates can achieve
results equivalent to Method A in appendix F to this section. For
facilities in which no more than 5 pair of brakes or 5 clutches are
inspected, disassembled, repaired, or assembled per week, the method set
forth in paragraph [D] of appendix F to this section may be used.
(ii) The employer may also comply by using an equivalent method
which follows written procedures, which the employer demonstrates can
achieve equivalent exposure reductions as do the two ``preferred
methods.'' Such demonstration must include monitoring data conducted
under workplace conditions closely resembling the process, type of
asbestos containing materials, control method, work practices and
environmental conditions which the equivalent method will be used, or
objective data, which document that under all reasonably foreseeable
conditions of brake and clutch repair applications, the method results
in exposures which are equivalent to the methods set out in appendix F
to this section.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Work operations, such as maintenance and repair activities, for
which engineering and work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the TWA and/or excursion limit.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance with 29 CFR 134 (b) through
(d) (except (d)(1)(iii)), and (f) through (m), which covers each
employee required by this section to use a respirator.
(ii) Employers must provide an employee with a tight-fitting,
powered air-purifying respirator (PAPR) instead of a negative pressure
respirator selected according to paragraph (g)(3) of this standard when
the employee chooses to use a PAPR and it provides adequate protection
to the employee.
(iii) No employee must be assigned to tasks requiring the use of
respirators if, based on their most recent medical examination, the
examining physician determines that the employee will be unable to
function normally using a respirator, or that the safety or health of
the employee or other employees will be impaired by the use of a
respirator. Such employees must be assigned to another job or given the
opportunity to transfer to a different position, the duties of which
they can perform. If such a transfer position is available, the position
must be with the same employer, in the same geographical area, and with
the same seniority, status, and rate of pay the employee had just prior
to such transfer.
[[Page 24]]
(3) Respirator selection. Employers must:
(i) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134; however,
employers must not select or use filtering facepiece respirators for
protection against asbestos fibers.
(ii) Provide HEPA filters for powered and non-powered air-purifying
respirators.
(h) Protective work clothing and equipment--(1) Provision and use.
If an employee is exposed to asbestos above the TWA and/or excursion
limit, or where the possibility of eye irritation exists, the employer
shall provide at no cost to the employee and ensure that the employee
uses appropriate protective work clothing and equipment such as, but not
limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, head coverings, and foot coverings; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment which complies with 1910.133 of this part.
(2) Removal and storage. (i) The employer shall ensure that
employees remove work clothing contaminated with asbestos only in change
rooms provided in accordance with paragraph (i)(1) of this section.
(ii) The employer shall ensure that no employee takes contaminated
work clothing out of the change room, except those employees authorized
to do so for the purpose of laundering, maintenance, or disposal.
(iii) Contaminated work clothing shall be placed and stored in
closed containers which prevent dispersion of the asbestos outside the
container.
(iv) The employer shall ensure that containers of contaminated
protective devices or work clothing, which are to be taken out of change
rooms or the workplace for cleaning, maintenance or disposal, bear
labels in accordance with paragraph (j) of this section.
(3) Cleaning and replacement. (i) The employer shall clean, launder,
repair, or replace protective clothing and equipment required by this
paragraph to maintain their effectiveness. The employer shall provide
clean protective clothing and equipment at least weekly to each affected
employee.
(ii) The employer shall prohibit the removal of asbestos from
protective clothing and equipment by blowing or shaking. (iii)
Laundering of contaminated clothing shall be done so as to prevent the
release of airborne fibers of asbestos in excess of the permissible
exposure limits prescribed in paragraph (c) of this section.
(iv) Any employer who gives contaminated clothing to another person
for laundering shall inform such person of the requirement in paragraph
(h)(3)(iii) of this section to effectively prevent the release of
airborne fibers of asbestos in excess of the permissible exposure
limits.
(v) The employer shall inform any person who launders or cleans
protective clothing or equipment contaminated with asbestos of the
potentially harmful effects of exposure to asbestos.
(vi) The employer shall ensure that contaminated clothing is
transported in sealed impermeable bags, or other closed, impermeable
containers, and labeled in accordance with paragraph (j) of this
section.
(i) Hygiene facilities and practices--(1) Change rooms. (i) The
employer shall provide clean change rooms for employees who work in
areas where their airborne exposure to asbestos is above the TWA and/or
excursion limit.
(ii) The employer shall ensure that change rooms are in accordance
with 1910.141(e) of this part, and are equipped with two separate
lockers or storage facilities, so separated as to prevent contamination
of the employee's street clothes from his protective work clothing and
equipment.
(2) Showers. (i) The employer shall ensure that employees who work
in areas where their airborne exposure is above the TWA and/or excursion
limit, shower at the end of the work shift.
(ii) The employer shall provide shower facilities which comply with
1910.141(d)(3) of this part.
(iii) The employer shall ensure that employees who are required to
shower pursuant to paragraph (i)(2)(i) of this section do not leave the
workplace wearing any clothing or equipment worn during the work shift.
[[Page 25]]
(3) Lunchrooms. (i) The employer shall provide lunchroom facilities
for employees who work in areas where their airborne exposure is above
the TWA and/or excursion limit.
(ii) The employer shall ensure that lunchroom facilities have a
positive pressure, filtered air supply, and are readily accessible to
employees.
(iii) The employer shall ensure that employees who work in areas
where their airborne exposure is above the PEL and/or excursion limit
wash their hands and faces prior to eating, drinking or smoking.
(iv) The employer shall ensure that employees do not enter lunchroom
facilities with protective work clothing or equipment unless surface
asbestos fibers have been removed from the clothing or equipment by
vacuuming or other method that removes dust without causing the asbestos
to become airborne.
(4) Smoking in work areas. The employer shall ensure that employees
do not smoke in work areas where they are occupationally exposed to
asbestos because of activities in that work area.
(j) Communication of hazards to employees--Introduction. This
section applies to the communication of information concerning asbestos
hazards in general industry to facilitate compliance with this standard.
Asbestos exposure in general industry occurs in a wide variety of
industrial and commercial settings. Employees who manufacture asbestos-
containing products may be exposed to asbestos fibers. Employees who
repair and replace automotive brakes and clutches may be exposed to
asbestos fibers. In addition, employees engaged in housekeeping
activities in industrial facilities with asbestos product manufacturing
operations, and in public and commercial buildings with installed
asbestos containing materials may be exposed to asbestos fibers. Most of
these workers are covered by this general industry standard, with the
exception of state or local governmental employees in non-state plan
states. It should be noted that employees who perform housekeeping
activities during and after construction activities are covered by the
asbestos construction standard, 29 CFR 1926.1101, formerly 1926.58.
However, housekeeping employees, regardless of industry designation,
should know whether building components they maintain may expose them to
asbestos. The same hazard communication provisions will protect
employees who perform housekeeping operations in all three asbestos
standards; general industry, construction, and shipyard employment. As
noted in the construction standard, building owners are often the only
and/or best source of information concerning the presence of previously
installed asbestos containing building materials. Therefore they, along
with employers of potentially exposed employees, are assigned specific
information conveying and retention duties under this section.
(1) Hazard communication--general. (i) Chemical manufacturers,
importers, distributors and employers shall comply with all requirements
of the Hazard Communication Standard (HCS) (Sec. 1910.1200) for
asbestos.
(ii) In classifying the hazards of asbestos at least the following
hazards are to be addressed: Cancer and lung effects.
(iii) Employers shall include asbestos in the hazard communication
program established to comply with the HCS (Sec. 1910.1200). Employers
shall ensure that each employee has access to labels on containers of
asbestos and to safety data sheets, and is trained in accordance with
the requirements of HCS and paragraph (j)(7) of this section.
(2) Installed Asbestos Containing Material. Employers and building
owners are required to treat installed TSI and sprayed on and troweled-
on surfacing materials as ACM in buildings constructed no later than
1980 for purposes of this standard. These materials are designated
``presumed ACM or PACM'', and are defined in paragraph (b) of this
section. Asphalt and vinyl flooring material installed no later than
1980 also must be treated as asbestos-containing. The employer or
building owner may demonstrate that PACM and flooring material do not
contain asbestos by complying with paragraph (j)(8)(iii) of this
section.
(3) Duties of employers and building and facility owners. (i)
Building and facility owners shall determine the presence, location, and
quantity of ACM
[[Page 26]]
and/or PACM at the work site. Employers and building and facility owners
shall exercise due diligence in complying with these requirements to
inform employers and employees about the presence and location of ACM
and PACM.
(ii) Building and facility owners shall maintain records of all
information required to be provided pursuant to this section and/or
otherwise known to the building owner concerning the presence, location
and quantity of ACM and PACM in the building/facility. Such records
shall be kept for the duration of ownership and shall be transferred to
successive owners.
(iii) Building and facility owners shall inform employers of
employees, and employers shall inform employees who will perform
housekeeping activities in areas which contain ACM and/or PACM of the
presence and location of ACM and/or PACM in such areas which may be
contacted during such activities.
(4) Warning signs--(i) Posting. Warning signs shall be provided and
displayed at each regulated area. In addition, warning signs shall be
posted at all approaches to regulated areas so that an employee may read
the signs and take necessary protective steps before entering the area.
(ii) Sign specifications:
(A) The warning signs required by paragraph (j)(4)(i) of this
section shall bear the following legend:
DANGER
ASBESTOS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AUTHORIZED PERSONNEL ONLY
(B) In addition, where the use of respirators and protective
clothing is required in the regulated area under this section, the
warning signs shall include the following:
WEAR RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING IN THIS AREA
(C) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (j)(4)(ii)(A) of this section:
DANGER
ASBESTOS
CANCER AND LUNG DISEASE
HAZARD
AUTHORIZED PERSONNEL ONLY
(D) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (j)(4)(ii)(B) of this section:
RESPIRATORS AND PROTECTIVE CLOTHING ARE REQUIRED IN THIS AREA
(iii) The employer shall ensure that employees working in and
contiguous to regulated areas comprehend the warning signs required to
be posted by paragraph (j)(4)(i) of this section. Means to ensure
employee comprehension may include the use of foreign languages,
pictographs and graphics.
(iv) At the entrance to mechanical rooms/areas in which employees
reasonably can be expected to enter and which contain ACM and/or PACM,
the building owner shall post signs which identify the material which is
present, its location, and appropriate work practices which, if
followed, will ensure that ACM and/or PACM will not be disturbed. The
employer shall ensure, to the extent feasible, that employees who come
in contact with these signs can comprehend them. Means to ensure
employee comprehension may include the use of foreign languages,
pictographs, graphics, and awareness training.
(5) Warning labels--(i) Labeling. Labels shall be affixed to all raw
materials, mixtures, scrap, waste, debris, and other products containing
asbestos fibers, or to their containers. When a building owner or
employer identifies previously installed ACM and/or PACM, labels or
signs shall be affixed or posted so that employees will be notified of
what materials contain ACM and/or PACM. The employer shall attach such
labels in areas where they will clearly be noticed by employees who are
likely to be exposed, such as at the entrance to mechanical room/areas.
Signs required by paragraph (j) of this section may be posted in lieu of
labels so long as they contain the information required for labeling.
(ii) Label specifications. In addition to the requirements of
paragraph (j)(1), the employer shall ensure that labels of bags or
containers of protective clothing and equipment, scrap, waste, and
debris containing asbestos fibers include the following information:
[[Page 27]]
DANGER
CONTAINS ASBESTOS FIBERS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
DO NOT BREATHE DUST
AVOID CREATING DUST
(iii) Prior to June 1, 2015, employers may include the following
information on raw materials, mixtures or labels of bags or containers
of protective clothing and equipment, scrap, waste, and debris
containing asbestos fibers in lieu of the labeling requirements in
paragraphs (j)(1)(i) and (j)(5)(ii) of this section:
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE HAZARD
(6) The provisions for labels and for safety data sheets required by
paragraph (j) of this section do not apply where:
(i) Asbestos fibers have been modified by a bonding agent, coating,
binder, or other material provided that the manufacturer can demonstrate
that during any reasonably foreseeable use, handling, storage, disposal,
processing, or transportation, no airborne concentrations of fibers of
asbestos in excess of the TWA permissible exposure level and/or
excursion limit will be released or
(ii) Asbestos is present in a product in concentrations less than
1.0%.
(7) Employee information and training. (i) The employer shall train
each employee who is exposed to airborne concentrations of asbestos at
or above the PEL and/or excursion limit in accordance with the
requirements of this section. The employer shall institute a training
program and ensure employee participation in the program.
(ii) Training shall be provided prior to or at the time of initial
assignment and at least annually thereafter.
(iii) The training program shall be conducted in a manner which the
employee is able to understand. The employer shall ensure that each
employee is informed of the following:
(A) The health effects associated with asbestos exposure;
(B) The relationship between smoking and exposure to asbestos
producing lung cancer:
(C) The quantity, location, manner of use, release, and storage of
asbestos, and the specific nature of operations which could result in
exposure to asbestos;
(D) The engineering controls and work practices associated with the
employee's job assignment;
(E) The specific procedures implemented to protect employees from
exposure to asbestos, such as appropriate work practices, emergency and
clean-up procedures, and personal protective equipment to be used;
(F) The purpose, proper use, and limitations of respirators and
protective clothing, if appropriate;
(G) The purpose and a description of the medical surveillance
program required by paragraph (l) of this section;
(H) The content of this standard, including appendices.
(I) The names, addresses and phone numbers of public health
organizations which provide information, materials, and/or conduct
programs concerning smoking cessation. The employer may distribute the
list of such organizations contained in appendix I to this section, to
comply with this requirement.
(J) The requirements for posting signs and affixing labels and the
meaning of the required legends for such signs and labels.
(iv) The employer shall also provide, at no cost to employees who
perform housekeeping operations in an area which contains ACM or PACM,
an asbestos awareness training course, which shall at a minimum contain
the following elements: health effects of asbestos, locations of ACM and
PACM in the building/facility, recognition of ACM and PACM damage and
deterioration, requirements in this standard relating to housekeeping,
and proper response to fiber release episodes, to all employees who
perform housekeeping work in areas where ACM and/or PACM is present.
Each such employee shall be so trained at least once a year.
(v) Access to information and training materials.
(A) The employer shall make a copy of this standard and its
appendices readily available without cost to all affected employees.
[[Page 28]]
(B) The employer shall provide, upon request, all materials relating
to the employee information and training program to the Assistant
Secretary and the training program to the Assistant Secretary and the
Director.
(C) The employer shall inform all employees concerning the
availability of self-help smoking cessation program material. Upon
employee request, the employer shall distribute such material,
consisting of NIH Publication No. 89-1647, or equivalent self-help
material, which is approved or published by a public health organization
listed in appendix I to this section.
(8) Criteria to rebut the designation of installed material as PACM.
(i) At any time, an employer and/or building owner may demonstrate, for
purposes of this standard, that PACM does not contain asbestos. Building
owners and/or employers are not required to communicate information
about the presence of building material for which such a demonstration
pursuant to the requirements of paragraph (j)(8)(ii) of this section has
been made. However, in all such cases, the information, data and
analysis supporting the determination that PACM does not contain
asbestos, shall be retained pursuant to paragraph (m) of this section.
(ii) An employer or owner may demonstrate that PACM does not contain
asbestos by the following:
(A) Having a completed inspection conducted pursuant to the
requirements of AHERA (40 CFR 763, subpart E) which demonstrates that no
ACM is present in the material; or
(B) Performing tests of the material containing PACM which
demonstrate that no ACM is present in the material. Such tests shall
include analysis of bulk samples collected in the manner described in 40
CFR 763.86. The tests, evaluation and sample collection shall be
conducted by an accredited inspector or by a CIH. Analysis of samples
shall be performed by persons or laboratories with proficiency
demonstrated by current successful participation in a nationally
recognized testing program such as the National Voluntary Laboratory
Accreditation Program (NVLAP) or the National Institute for Standards
and Technology (NIST) or the Round Robin for bulk samples administered
by the American Industrial Hygiene Association (AIHA) or an equivalent
nationally-recognized round robin testing program.
(iii) The employer and/or building owner may demonstrate that
flooring material including associated mastic and backing does not
contain asbestos, by a determination of an industrial hygienist based
upon recognized analytical techniques showing that the material is not
ACM.
(k) Housekeeping. (1) All surfaces shall be maintained as free as
practicable of ACM waste and debris and accompanying dust.
(2) All spills and sudden releases of material containing asbestos
shall be cleaned up as soon as possible.
(3) Surfaces contaminated with asbestos may not be cleaned by the
use of compressed air.
(4) Vacuuming. HEPA-filtered vacuuming equipment shall be used for
vacuuming asbestos containing waste and debris. The equipment shall be
used and emptied in a manner which minimizes the reentry of asbestos
into the workplace.
(5) Shoveling, dry sweeping and dry clean-up of asbestos may be used
only where vacuuming and/or wet cleaning are not feasible.
(6) Waste disposal. Waste, scrap, debris, bags, containers,
equipment, and clothing contaminated with asbestos consigned for
disposal, shall be collected, recycled and disposed of in sealed
impermeable bags, or other closed, impermeable containers.
(7) Care of asbestos-containing flooring material.
(i) Sanding of asbestos-containing floor material is prohibited.
(ii) Stripping of finishes shall be conducted using low abrasion
pads at speeds lower than 300 rpm and wet methods.
(iii) Burnishing or dry buffing may be performed only on asbestos-
containing flooring which has sufficient finish so that the pad cannot
contact the asbestos-containing material.
(8) Waste and debris and accompanying dust in an area containing
accessible ACM and/or PACM or visibly deteriorated ACM, shall not be
dusted or swept dry, or vacuumed without using a HEPA filter.
[[Page 29]]
(l) Medical surveillance--(1) General--(i) Employees covered. The
employer shall institute a medical surveillance program for all
employees who are or will be exposed to airborne concentrations of
fibers of asbestos at or above the TWA and/or excursion limit.
(ii) Examination by a physician. (A) The employer shall ensure that
all medical examinations and procedures are performed by or under the
supervision of a licensed physician, and shall be provided without cost
to the employee and at a reasonable time and place.
(B) Persons other than licensed physicians, who administer the
pulmonary function testing required by this section, shall complete a
training course in spirometry sponsored by an appropriate academic or
professional institution.
(2) Pre-placement examinations. (i) Before an employee is assigned
to an occupation exposed to airborne concentrations of asbestos fibers
at or above the TWA and/or excursion limit, a pre-placement medical
examination shall be provided or made available by the employer.
(ii) Such examination shall include, as a minimum, a medical and
work history; a complete physical examination of all systems with
emphasis on the respiratory system, the cardiovascular system and
digestive tract; completion of the respiratory disease standardized
questionnaire in appendix D to this section, part 1; a chest
roentgenogram (posterior-anterior 14x17 inches); pulmonary function
tests to include forced vital capacity (FVC) and forced expiratory
volume at 1 second (FEV(1.0)); and any additional tests deemed
appropriate by the examining physician. Interpretation and
classification of chest roentgenogram shall be conducted in accordance
with appendix E to this section.
(3) Periodic examinations. (i) Periodic medical examinations shall
be made available annually.
(ii) The scope of the medical examination shall be in conformance
with the protocol established in paragraph (l)(2)(ii) of this section,
except that the frequency of chest roentgenogram shall be conducted in
accordance with Table 1, and the abbreviated standardized questionnaire
contained in, part 2 of appendix D to this section shall be administered
to the employee.
Table 1--Frequency of Chest Roentgenogram
----------------------------------------------------------------------------------------------------------------
Age of employee
Years since first exposure --------------------------------------------------------------------------------
15 to 35 35+ to 45 45+
----------------------------------------------------------------------------------------------------------------
0 to 10........................ Every 5 years.............. Every 5 years............. Every 5 years.
10+............................ Every 5 years.............. Every 2 years............. Every 1 year.
----------------------------------------------------------------------------------------------------------------
(4) Termination of employment examinations. (i) The employer shall
provide, or make available, a termination of employment medical
examination for any employee who has been exposed to airborne
concentrations of fibers of asbestos at or above the TWA and/or
excursion limit.
(ii) The medical examination shall be in accordance with the
requirements of the periodic examinations stipulated in paragraph (l)(3)
of this section, and shall be given within 30 calendar days before or
after the date of termination of employment.
(5) Recent examinations. No medical examination is required of any
employee, if adequate records show that the employee has been examined
in accordance with any of paragraphs ((l)(2) through (l)(4)) of this
section within the past 1 year period. A pre- employment medical
examination which was required as a condition of employment by the
employer, may not be used by that employer to meet the requirements of
this paragraph, unless the cost of such examination is borne by the
employer.
(6) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and Appendices D and E.
[[Page 30]]
(ii) A description of the affected employee's duties as they relate
to the employee's exposure.
(iii) The employee's representative exposure level or anticipated
exposure level.
(iv) A description of any personal protective and respiratory
equipment used or to be used.
(v) Information from previous medical examinations of the affected
employee that is not otherwise available to the examining physician.
(7) Physician's written opinion. (i) The employer shall obtain a
written opinion from the examining physician. This written opinion shall
contain the results of the medical examination and shall include:
(A) The physician's opinion as to whether the employee has any
detected medical conditions that would place the employee at an
increased risk of material health impairment from exposure to asbestos;
(B) Any recommended limitations on the employee or upon the use of
personal protective equipment such as clothing or respirators;
(C) A statement that the employee has been informed by the physician
of the results of the medical examination and of any medical conditions
resulting from asbestos exposure that require further explanation or
treatment; and
(D) A statement that the employee has been informed by the physician
of the increased risk of lung cancer attributable to the combined effect
of smoking and asbestos exposure.
(ii) The employer shall instruct the physician not to reveal in the
written opinion given to the employer specific findings or diagnoses
unrelated to occupational exposure to asbestos.
(iii) The employer shall provide a copy of the physician's written
opinion to the affected employee within 30 days from its receipt.
(m) Recordkeeping--(1) Exposure measurements.
Note: The employer may utilize the services of competent
organizations such as industry trade associations and employee
associations to maintain the records required by this section.
(i) The employer shall keep an accurate record of all measurements
taken to monitor employee exposure to asbestos as prescribed in
paragraph (d) of this section.
(ii) This record shall include at least the following information:
(A) The date of measurement;
(B) The operation involving exposure to asbestos which is being
monitored;
(C) Sampling and analytical methods used and evidence of their
accuracy;
(D) Number, duration, and results of samples taken;
(E) Type of respiratory protective devices worn, if any; and
(F) Name, social security number and exposure of the employees whose
exposure are represented.
(iii) The employer shall maintain this record for at least thirty
(30) years, in accordance with 29 CFR 1910.20.
(2) Objective data for exempted operations. (i) Where the
processing, use, or handling of products made from or containing
asbestos is exempted from other requirements of this section under
paragraph (d)(2)(iii) of this section, the employer shall establish and
maintain an accurate record of objective data reasonably relied upon in
support of the exemption.
(ii) The record shall include at least the following:
(A) The product qualifying for exemption;
(B) The source of the objective data;
(C) The testing protocol, results of testing, and/or analysis of the
material for the release of asbestos;
(D) A description of the operation exempted and how the data support
the exemption; and
(E) Other data relevant to the operations, materials, processing, or
employee exposures covered by the exemption.
(iii) The employer shall maintain this record for the duration of
the employer's reliance upon such objective data.
(3) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance by paragraph (l)(1)(i) of this section, in accordance with
29 CFR 1910.1020.
(ii) The record shall include at least the following information:
(A) The name and social security number of the employee;
[[Page 31]]
(B) Physician's written opinions;
(C) Any employee medical complaints related to exposure to asbestos;
and
(D) A copy of the information provided to the physician as required
by paragraph (l)(6) of this section.
(iii) The employer shall ensure that this record is maintained for
the duration of employment plus thirty (30) years, in accordance with 29
CFR 1910.1020.
(4) Training. The employer shall maintain all employee training
records for one (1) year beyond the last date of employment of that
employee.
(5) Availability. (i) The employer, upon written request, shall make
all records required to be maintained by this section available to the
Assistant Secretary and the Director for examination and copying.
(ii) The employer, upon request shall make any exposure records
required by paragraph (m)(1) of this section available for examination
and copying to affected employees, former employees, designated
representatives and the Assistant Secretary, in accordance with 29 CFR
1910.1020 (a) through (e) and (g) through (i).
(iii) The employer, upon request, shall make employee medical
records required by paragraph (m)(3) of this section available for
examination and copying to the subject employee, to anyone having the
specific written consent of the subject employee, and the Assistant
Secretary, in accordance with 29 CFR 1910.1020.
(6) Transfer of records. The employer shall comply with the
requirements concerning transfer of records set forth in 29 CFR
1910.1020(h).
(n) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to asbestos conducted in accordance with paragraph (d) of this
section.
(2) Observation procedures. When observation of the monitoring of
employee exposure to asbestos requires entry into an area where the use
of protective clothing or equipment is required, the observer shall be
provided with and be required to use such clothing and equipment and
shall comply with all other applicable safety and health procedures.
(o) Appendices. (1) Appendices A, C, D, E, and F to this section are
incorporated as part of this section and the contents of these
Appendices are mandatory.
(2) Appendices B, G, H, I, and J to this section are informational
and are not intended to create any additional obligations not otherwise
imposed or to detract from any existing obligations.
Appendix A toSec. 1910.1001--OSHA Reference Method--Mandatory
This mandatory appendix specifies the procedure for analyzing air
samples for asbestos and specifies quality control procedures that must
be implemented by laboratories performing the analysis. The sampling and
analytical methods described below represent the elements of the
available monitoring methods (such as appendix B of their regulation,
the most current version of the OSHA method ID-160, or the most current
version of the NIOSH Method 7400). All employers who are required to
conduct air monitoring under paragraph (d) of the standard are required
to utilize analytical laboratories that use this procedure, or an
equivalent method, for collecting and analyzing samples.
Sampling and Analytical Procedure
1. The sampling medium for air samples shall be mixed cellulose
ester filter membranes. These shall be designated by the manufacturer as
suitable for asbestos counting. See below for rejection of blanks.
2. The preferred collection device shall be the 25-mm diameter
cassette with an open-faced 50-mm electrically conductive extension
cowl. The 37-mm cassette may be used if necessary but only if written
justification for the need to use the 37-mm filter cassette accompanies
the sample results in the employee's exposure monitoring record. Do not
reuse or reload cassettes for asbestos sample collection.
3. An air flow rate between 0.5 liter/min and 2.5 liters/min shall
be selected for the 25-mm cassette. If the 37-mm cassette is used, an
air flow rate between 1 liter/min and 2.5 liters/min shall be selected.
4. Where possible, a sufficient air volume for each air sample shall
be collected to yield between 100 and 1,300 fibers per square millimeter
on the membrane filter. If a filter darkens in appearance or if loose
dust is seen on the filter, a second sample shall be started.
5. Ship the samples in a rigid container with sufficient packing
material to prevent
[[Page 32]]
dislodging the collected fibers. Packing material that has a high
electrostatic charge on its surface (e.g., expanded polystyrene) cannot
be used because such material can cause loss of fibers to the sides of
the cassette.
6. Calibrate each personal sampling pump before and after use with a
representative filter cassette installed between the pump and the
calibration devices.
7. Personal samples shall be taken in the ``breathing zone'' of the
employee (i.e., attached to or near the collar or lapel near the
worker's face).
8. Fiber counts shall be made by positive phase contrast using a
microscope with an 8 to 10 X eyepiece and a 40 to 45 X objective for a
total magnification of approximately 400 X and a numerical aperture of
0.65 to 0.75. The microscope shall also be fitted with a green or blue
filter.
9. The microscope shall be fitted with a Walton-Beckett eyepiece
graticule calibrated for a field diameter of 100 micrometers (2 micrometers).
10. The phase-shift detection limit of the microscope shall be about
3 degrees measured using the HSE phase shift test slide as outlined
below.
a. Place the test slide on the microscope stage and center it under
the phase objective.
b. Bring the blocks of grooved lines into focus.
Note: The slide consists of seven sets of grooved lines (ca. 20
grooves to each block) in descending order of visibility from sets 1 to
7, seven being the least visible. The requirements for asbestos counting
are that the microscope optics must resolve the grooved lines in set 3
completely, although they may appear somewhat faint, and that the
grooved lines in sets 6 and 7 must be invisible. Sets 4 and 5 must be at
least partially visible but may vary slightly in visibility between
microscopes. A microscope that fails to meet these requirements has
either too low or too high a resolution to be used for asbestos
counting.
c. If the image deteriorates, clean and adjust the microscope
optics. If the problem persists, consult the microscope manufacturer.
11. Each set of samples taken will include 10% field blanks or a
minimum of 2 field blanks. These blanks must come from the same lot as
the filters used for sample collection. The field blank results shall be
averaged and subtracted from the analytical results before reporting. A
set consists of any sample or group of samples for which an evaluation
for this standard must be made. Any samples represented by a field blank
having a fiber count in excess of the detection limit of the method
being used shall be rejected.
12. The samples shall be mounted by the acetone/triacetin method or
a method with an equivalent index of refraction and similar clarity.
13. Observe the following counting rules.
a. Count only fibers equal to or longer than 5 micrometers. Measure
the length of curved fibers along the curve.
b. In the absence of other information, count all particles as
asbesto that have a length-to-width ratio (aspect ratio) of 3:1 or
greater.
c. Fibers lying entirely within the boundary of the Walton-Beckett
graticule field shall receive a count of 1. Fibers crossing the boundary
once, having one end within the circle, shall receive the count of one
half (\1/2\). Do not count any fiber that crosses the graticule boundary
more than once. Reject and do not count any other fibers even though
they may be visible outside the graticule area.
d. Count bundles of fibers as one fiber unless individual fibers can
be identified by observing both ends of an individual fiber.
e. Count enough graticule fields to yield 100 fibers. Count a
minimum of 20 fields; stop counting at 100 fields regardless of fiber
count.
14. Blind recounts shall be conducted at the rate of 10 percent.
Quality Control Procedures
1. Intralaboratory program. Each laboratory and/or each company with
more than one microscopist counting slides shall establish a
statistically designed quality assurance program involving blind
recounts and comparisons between microscopists to monitor the
variability of counting by each microscopist and between microscopists.
In a company with more than one laboratory, the program shall include
all laboratories and shall also evaluate the laboratory-to-laboratory
variability.
2.a. Interlaboratory program. Each laboratory analyzing asbestos
samples for compliance determination shall implement an interlaboratory
quality assurance program that as a minimum includes participation of at
least two other independent laboratories. Each laboratory shall
participate in round robin testing at least once every 6 months with at
least all the other laboratories in its interlaboratory quality
assurance group. Each laboratory shall submit slides typical of its own
work load for use in this program. The round robin shall be designed and
results analyzed using appropriate statistical methodology.
2.b. All laboratories should also participate in a national sample
testing scheme such as the Proficiency Analytical Testing Program (PAT),
or the Asbestos Registry sponsored by the American Industrial Hygiene
Association (AIHA).
[[Page 33]]
3. All individuals performing asbestos analysis must have taken the
NIOSH course for sampling and evaluating airborne asbestos dust or an
equalivalent course.
4. When the use of different microscopes contributes to differences
between counters and laboratories, the effect of the different
microscope shall be evaluated and the microscope shall be replaced, as
necessary.
5. Current results of these quality assurance programs shall be
posted in each laboratory to keep the microscopists informed.
Appendix B toSec. 1910.1001--Detailed Procedures for Asbestos Sampling
and Analysis--Non-mandatory
Matrix Air:
OSHA Permissible Exposure Limits:
Time Weighted Average.............. 0.1 fiber/cc
Excursion Level (30 minutes)....... 1.0 fiber/cc
Collection Procedure:
A known volume of air is drawn through a 25-mm diameter cassette
containing a mixed-cellulose ester filter. The cassette must be equipped
with an electrically conductive 50-mm extension cowl. The sampling time
and rate are chosen to give a fiber density of between 100 to 1,300
fibers/mm\2\ on the filter.
Recommended Sampling Rate.............. 0.5 to 5.0 liters/minute (L/
min)
Recommended Air Volumes:
Minimum............................ 25 L
Maximum............................ 2,400 L
------------------------------------------------------------------------
Analytical Procedure: A portion of the sample filter is cleared and
prepared for asbestos fiber counting by Phase Contrast Microscopy (PCM)
at 400X.
Commercial manufacturers and products mentioned in this method are
for descriptive use only and do not constitute endorsements by USDOL-
OSHA. Similar products from other sources can be substituted.
1. Introduction
This method describes the collection of airborne asbestos fibers
using calibrated sampling pumps with mixed-cellulose ester (MCE) filters
and analysis by phase contrast microscopy (PCM). Some terms used are
unique to this method and are defined below:
Asbestos: A term for naturally occurring fibrous minerals. Asbestos
includes chrysotile, crocidolite, amosite (cummingtonite-grunerite
asbestos), tremolite asbestos, actinolite asbestos, anthophyllite
asbestos, and any of these minerals that have been chemically treated
and/or altered. The precise chemical formulation of each species will
vary with the location from which it was mined. Nominal compositions are
listed:
Chrysotile................................ Mg3 Si2 O5(OH)4
Crocidolite............................... Na2 Fe32+ Fe23 + Si8 O22
(OH)\2\
Amosite................................... (Mg,Fe)7 Si8 O22 (OH)2
Tremolite-actinolite...................... Ca2(Mg,Fe)5 Si8 O22 (OH)2
Anthophyllite............................. (Mg,Fe)7 Si8 O22 (OH)2
Asbestos Fiber: A fiber of asbestos which meets the criteria
specified below for a fiber.
Aspect Ratio: The ratio of the length of a fiber to it's diameter
(e.g. 3:1, 5:1 aspect ratios).
Cleavage Fragments: Mineral particles formed by comminution of
minerals, especially those characterized by parallel sides and a
moderate aspect ratio (usually less than 20:1).
Detection Limit: The number of fibers necessary to be 95% certain
that the result is greater than zero.
Differential Counting: The term applied to the practice of excluding
certain kinds of fibers from the fiber count because they do not appear
to be asbestos.
Fiber: A particle that is 5 [micro]m or longer, with a length-to-
width ratio of 3 to 1 or longer.
Field: The area within the graticule circle that is superimposed on
the microscope image.
Set: The samples which are taken, submitted to the laboratory,
analyzed, and for which, interim or final result reports are generated.
Tremolite, Anthophyllite, and Actinolite: The non-asbestos form of
these minerals which meet the definition of a fiber. It includes any of
these minerals that have been chemically treated and/or altered.
Walton-Beckett Graticule: An eyepiece graticule specifically
designed for asbestos fiber counting. It consists of a circle with a
projected diameter of 100 2 [micro]m (area of about 0.00785 mm\2\) with
a crosshair having tic-marks at 3-[micro]m intervals in one direction
and 5-[micro]m in the orthogonal direction. There are marks around the
periphery of the circle to demonstrate the proper sizes and shapes of
fibers. This design is reproduced in Figure 1. The disk is placed in one
of the microscope eyepieces so that the design is superimposed on the
field of view.
1.1. History
Early surveys to determine asbestos exposures were conducted using
impinger counts of total dust with the counts expressed as million
particles per cubic foot. The British Asbestos Research Council
recommended filter membrane counting in 1969. In July 1969, the Bureau
of Occupational Safety and Health published a filter membrane method for
counting asbestos fibers in the United States. This method was refined
by NIOSH and published as P CAM 239. On May 29, 1971, OSHA specified
filter membrane sampling with phase contrast counting for evaluation of
asbestos exposures at work sites in the United States. The use of this
technique was again required by OSHA in 1986. Phase contrast microscopy
has continued to be the method of choice for the measurement of
occupational exposure to asbestos.
[[Page 34]]
1.2. Principle
Air is drawn through a MCE filter to capture airborne asbestos
fibers. A wedge shaped portion of the filter is removed, placed on a
glass microscope slide and made transparent. A measured area (field) is
viewed by PCM. All the fibers meeting defined criteria for asbestos are
counted and considered a measure of the airborne asbestos concentration.
1.3. Advantages and Disadvantages
There are four main advantages of PCM over other methods:
(1) The technique is specific for fibers. Phase contrast is a fiber
counting technique which excludes non-fibrous particles from the
analysis.
(2) The technique is inexpensive and does not require specialized
knowledge to carry out the analysis for total fiber counts.
(3) The analysis is quick and can be performed on-site for rapid
determination of air concentrations of asbestos fibers.
(4) The technique has continuity with historical epidemiological
studies so that estimates of expected disease can be inferred from long-
term determinations of asbestos exposures.
The main disadvantage of PCM is that it does not positively identify
asbestos fibers. Other fibers which are not asbestos may be included in
the count unless differential counting is performed. This requires a
great deal of experience to adequately differentiate asbestos from non-
asbestos fibers. Positive identification of asbestos must be performed
by polarized light or electron microscopy techniques. A further
disadvantage of PCM is that the smallest visible fibers are about 0.2
[micro]m in diameter while the finest asbestos fibers may be as small as
0.02 [micro]m in diameter. For some exposures, substantially more fibers
may be present than are actually counted.
1.4. Workplace Exposure
Asbestos is used by the construction industry in such products as
shingles, floor tiles, asbestos cement, roofing felts, insulation and
acoustical products. Non-construction uses include brakes, clutch
facings, paper, paints, plastics, and fabrics. One of the most
significant exposures in the workplace is the removal and encapsulation
of asbestos in schools, public buildings, and homes. Many workers have
the potential to be exposed to asbestos during these operations.
About 95% of the asbestos in commercial use in the United States is
chrysotile. Crocidolite and amosite make up most of the remainder.
Anthophyllite and tremolite or actinolite are likely to be encountered
as contaminants in various industrial products.
1.5. Physical Properties
Asbestos fiber possesses a high tensile strength along its axis, is
chemically inert, non-combustible, and heat resistant. It has a high
electrical resistance and good sound absorbing properties. It can be
weaved into cables, fabrics or other textiles, and also matted into
asbestos papers, felts, or mats.
2. Range and Detection Limit
2.1. The ideal counting range on the filter is 100 to 1,300 fibers/
mm\2\. With a Walton-Beckett graticule this range is equivalent to 0.8
to 10 fibers/field. Using NIOSH counting statistics, a count of 0.8
fibers/field would give an approximate coefficient of variation (CV) of
0.13.
2.2. The detection limit for this method is 4.0 fibers per 100
fields or 5.5 fibers/mm\2\. This was determined using an equation to
estimate the maximum CV possible at a specific concentration (95%
confidence) and a Lower Control Limit of zero. The CV value was then
used to determine a corresponding concentration from historical CV vs
fiber relationships. As an example:
Lower Control Limit (95% Confidence) = AC - 1.645(CV)(AC)
Where:
AC = Estimate of the airborne fiber concentration (fibers/cc) Setting
the Lower Control Limit = 0 and solving for CV:
0 = AC - 1.645(CV)(AC)
CV = 0.61
This value was compared with CV vs. count curves. The count at which
CV = 0.61 for Leidel-Busch counting statistics or for an OSHA Salt Lake
Technical Center (OSHA-SLTC) CV curve (see appendix A for further
information) was 4.4 fibers or 3.9 fibers per 100 fields, respectively.
Although a lower detection limit of 4 fibers per 100 fields is supported
by the OSHA-SLTC data, both data sets support the 4.5 fibers per 100
fields value.
3. Method Performance--Precision and Accuracy
Precision is dependent upon the total number of fibers counted and
the uniformity of the fiber distribution on the filter. A general rule
is to count at least 20 and not more than 100 fields. The count is
discontinued when 100 fibers are counted, provided that 20 fields have
already been counted. Counting more than 100 fibers results in only a
small gain in precision. As the total count drops below 10 fibers, an
accelerated loss of precision is noted.
At this time, there is no known method to determine the absolute
accuracy of the asbestos analysis. Results of samples prepared through
the Proficiency Analytical Testing (PAT) Program and analyzed by the
OSHA-SLTC showed no significant bias when compared to PAT reference
values. The PAT
[[Page 35]]
samples were analyzed from 1987 to 1989 (N=36) and the concentration
range was from 120 to 1,300 fibers/mm\2\.
4. Interferences
Fibrous substances, if present, may interfere with asbestos
analysis.
Some common fibers are:
fiberglass
anhydrite
plant fibers
perlite veins
gypsum
some synthetic fibers
membrane structures
sponge spicules
diatoms
microorganisms
wollastonite
The use of electron microscopy or optical tests such as polarized
light, and dispersion staining may be used to differentiate these
materials from asbestos when necessary.
5. Sampling
5.1. Equipment
5.1.1. Sample assembly (The assembly is shown in Figure 3).
Conductive filter holder consisting of a 25-mm diameter, 3-piece
cassette having a 50-mm long electrically conductive extension cowl.
Backup pad, 25-mm, cellulose. Membrane filter, mixed-cellulose ester
(MCE), 25-mm, plain, white, 0.4 to 1.2-[micro]m pore size.
Notes: (a) Do not re-use cassettes.
(b) Fully conductive cassettes are required to reduce fiber loss to
the sides of the cassette due to electrostatic attraction.
(c) Purchase filters which have been selected by the manufacturer
for asbestos counting or analyze representative filters for fiber
background before use. Discard the filter lot if more than 4 fibers/100
fields are found.
(d) To decrease the possibility of contamination, the sampling
system (filter-backup pad-cassette) for asbestos is usually preassembled
by the manufacturer.
(e) Other cassettes, such as the Bell-mouth, may be used within the
limits of their validation.
5.1.2. Gel bands for sealing cassettes.
5.1.3. Sampling pump.
Each pump must be a battery operated, self-contained unit small
enough to be placed on the monitored employee and not interfere with the
work being performed. The pump must be capable of sampling at the
collection rate for the required sampling time.
5.1.4. Flexible tubing, 6-mm bore.
5.1.5. Pump calibration.
Stopwatch and bubble tube/burette or electronic meter.
5.2. Sampling Procedure
5.2.1. Seal the point where the base and cowl of each cassette meet
with a gel band or tape.
5.2.2. Charge the pumps completely before beginning.
5.2.3. Connect each pump to a calibration cassette with an
appropriate length of 6-mm bore plastic tubing. Do not use luer
connectors--the type of cassette specified above has built-in adapters.
5.2.4. Select an appropriate flow rate for the situation being
monitored. The sampling flow rate must be between 0.5 and 5.0 L/min for
personal sampling and is commonly set between 1 and 2 L/min. Always
choose a flow rate that will not produce overloaded filters.
5.2.5. Calibrate each sampling pump before and after sampling with a
calibration cassette in-line (Note: This calibration cassette should be
from the same lot of cassettes used for sampling). Use a primary
standard (e.g. bubble burette) to calibrate each pump. If possible,
calibrate at the sampling site.
Note: If sampling site calibration is not possible, environmental
influences may affect the flow rate. The extent is dependent on the type
of pump used. Consult with the pump manufacturer to determine dependence
on environmental influences. If the pump is affected by temperature and
pressure changes, correct the flow rate using the formula shown in the
section ``Sampling Pump Flow Rate Corrections'' at the end of this
appendix.
5.2.6. Connect each pump to the base of each sampling cassette with
flexible tubing. Remove the end cap of each cassette and take each air
sample open face. Assure that each sample cassette is held open side
down in the employee's breathing zone during sampling. The distance from
the nose/mouth of the employee to the cassette should be about 10 cm.
Secure the cassette on the collar or lapel of the employee using spring
clips or other similar devices.
5.2.7. A suggested minimum air volume when sampling to determine TWA
compliance is 25 L. For Excursion Limit (30 min sampling time)
evaluations, a minimum air volume of 48 L is recommended.
5.2.8. The most significant problem when sampling for asbestos is
overloading the filter with non-asbestos dust. Suggested maximum air
sample volumes for specific environments are:
------------------------------------------------------------------------
Environment Air vol. (L)
------------------------------------------------------------------------
Asbestos removal operations (visible dust).. 100
Asbestos removal operations (little dust)... 240
Office environments......................... 400
to
2,400
------------------------------------------------------------------------
Caution: Do not overload the filter with dust. High levels of non-
fibrous dust particles may obscure fibers on the filter and
[[Page 36]]
lower the count or make counting impossible. If more than about 25 to
30% of the field area is obscured with dust, the result may be biased
low. Smaller air volumes may be necessary when there is excessive non-
asbestos dust in the air.
While sampling, observe the filter with a small flashlight. If there
is a visible layer of dust on the filter, stop sampling, remove and seal
the cassette, and replace with a new sampling assembly. The total dust
loading should not exceed 1 mg.
5.2.9. Blank samples are used to determine if any contamination has
occurred during sample handling. Prepare two blanks for the first 1 to
20 samples. For sets containing greater than 20 samples, prepare blanks
as 10% of the samples. Handle blank samples in the same manner as air
samples with one exception: Do not draw any air through the blank
samples. Open the blank cassette in the place where the sample cassettes
are mounted on the employee. Hold it open for about 30 seconds. Close
and seal the cassette appropriately. Store blanks for shipment with the
sample cassettes.
5.2.10. Immediately after sampling, close and seal each cassette
with the base and plastic plugs. Do not touch or puncture the filter
membrane as this will invalidate the analysis.
5.2.11 Attach and secure a sample seal around each sample cassette
in such a way as to assure that the end cap and base plugs cannot be
removed without destroying the seal. Tape the ends of the seal together
since the seal is not long enough to be wrapped end-to-end. Also wrap
tape around the cassette at each joint to keep the seal secure.
5.3. Sample Shipment
5.3.1. Send the samples to the laboratory with paperwork requesting
asbestos analysis. List any known fibrous interferences present during
sampling on the paperwork. Also, note the workplace operation(s)
sampled.
5.3.2. Secure and handle the samples in such that they will not
rattle during shipment nor be exposed to static electricity. Do not ship
samples in expanded polystyrene peanuts, vermiculite, paper shreds, or
excelsior. Tape sample cassettes to sheet bubbles and place in a
container that will cushion the samples in such a manner that they will
not rattle.
5.3.3. To avoid the possibility of sample contamination, always ship
bulk samples in separate mailing containers.
6. Analysis
6.1. Safety Precautions
6.1.1. Acetone is extremely flammable and precautions must be taken
not to ignite it. Avoid using large containers or quantities of acetone.
Transfer the solvent in a ventilated laboratory hood. Do not use acetone
near any open flame. For generation of acetone vapor, use a spark free
heat source.
6.1.2. Any asbestos spills should be cleaned up immediately to
prevent dispersal of fibers. Prudence should be exercised to avoid
contamination of laboratory facilities or exposure of personnel to
asbestos. Asbestos spills should be cleaned up with wet methods and/or a
High Efficiency Particulate-Air (HEPA) filtered vacuum.
Caution: Do not use a vacuum without a HEPA filter--It will disperse
fine asbestos fibers in the air.
6.2. Equipment
6.2.1. Phase contrast microscope with binocular or trinocular head.
6.2.2. Widefield or Huygenian 10X eyepieces (Note: The eyepiece
containing the graticule must be a focusing eyepiece. Use a 40X phase
objective with a numerical aperture of 0.65 to 0.75).
6.2.3. Kohler illumination (if possible) with green or blue filter.
6.2.4. Walton-Beckett Graticule, type G-22 with 100 2 [micro]m projected diameter.
6.2.5. Mechanical stage.
A rotating mechanical stage is convenient for use with polarized
light.
6.2.6. Phase telescope.
6.2.7. Stage micrometer with 0.01-mm subdivisions.
6.2.8. Phase-shift test slide, mark II (Available from PTR optics
Ltd., and also McCrone).
6.2.9. Precleaned glass slides, 25 mm x 75 mm. One end can be
frosted for convenience in writing sample numbers, etc., or paste-on
labels can be used.
6.2.10. Cover glass 1 \1/2\.
6.2.11. Scalpel (10, curved blade).
6.2.12. Fine tipped forceps.
6.2.13. Aluminum block for clearing filter (see appendix D and
Figure 4).
6.2.14. Automatic adjustable pipette, 100- to 500-[micro]L.
6.2.15. Micropipette, 5 [micro]L.
6.3. Reagents
6.3.1. Acetone (HPLC grade).
6.3.2. Triacetin (glycerol triacetate).
6.3.3. Lacquer or nail polish.
6.4. Standard Preparation
A way to prepare standard asbestos samples of known concentration
has not been developed. It is possible to prepare replicate samples of
nearly equal concentration. This has been performed through the PAT
program. These asbestos samples are distributed by the AIHA to
participating laboratories.
Since only about one-fourth of a 25-mm sample membrane is required
for an asbestos count, any PAT sample can serve as a ``standard'' for
replicate counting.
[[Page 37]]
6.5. Sample Mounting
Note: See Safety Precautions in Section 6.1. before proceeding. The
objective is to produce samples with a smooth (non-grainy) background in
a medium with a refractive index of approximately 1.46. The technique
below collapses the filter for easier focusing and produces permanent
mounts which are useful for quality control and interlaboratory
comparison.
An aluminum block or similar device is required for sample
preparation.
6.5.1. Heat the aluminum block to about 70 [deg]C. The hot block
should not be used on any surface that can be damaged by either the heat
or from exposure to acetone.
6.5.2. Ensure that the glass slides and cover glasses are free of
dust and fibers.
6.5.3. Remove the top plug to prevent a vacuum when the cassette is
opened. Clean the outside of the cassette if necessary. Cut the seal
and/or tape on the cassette with a razor blade. Very carefully separate
the base from the extension cowl, leaving the filter and backup pad in
the base.
6.5.4. With a rocking motion cut a triangular wedge from the filter
using the scalpel. This wedge should be one-sixth to one-fourth of the
filter. Grasp the filter wedge with the forceps on the perimeter of the
filter which was clamped between the cassette pieces. DO NOT TOUCH the
filter with your finger. Place the filter on the glass slide sample side
up. Static electricity will usually keep the filter on the slide until
it is cleared.
6.5.5. Place the tip of the micropipette containing about 200
[micro]L acetone into the aluminum block. Insert the glass slide into
the receiving slot in the aluminum block. Inject the acetone into the
block with slow, steady pressure on the plunger while holding the
pipette firmly in place. Wait 3 to 5 seconds for the filter to clear,
then remove the pipette and slide from the aluminum block.
6.5.6. Immediately (less than 30 seconds) place 2.5 to 3.5 [micro]L
of triacetin on the filter (Note: Waiting longer than 30 seconds will
result in increased index of refraction and decreased contrast between
the fibers and the preparation. This may also lead to separation of the
cover slip from the slide).
6.5.7. Lower a cover slip gently onto the filter at a slight angle
to reduce the possibility of forming air bubbles. If more than 30
seconds have elapsed between acetone exposure and triacetin application,
glue the edges of the cover slip to the slide with lacquer or nail
polish.
6.5.8. If clearing is slow, warm the slide for 15 min on a hot plate
having a surface temperature of about 50 [deg]C to hasten clearing. The
top of the hot block can be used if the slide is not heated too long.
6.5.9. Counting may proceed immediately after clearing and mounting
are completed.
6.6. Sample Analysis
Completely align the microscope according to the manufacturer's
instructions. Then, align the microscope using the following general
alignment routine at the beginning of every counting session and more
often if necessary.
6.6.1. Alignment
(1) Clean all optical surfaces. Even a small amount of dirt can
significantly degrade the image.
(2) Rough focus the objective on a sample.
(3) Close down the field iris so that it is visible in the field of
view. Focus the image of the iris with the condenser focus. Center the
image of the iris in the field of view.
(4) Install the phase telescope and focus on the phase rings.
Critically center the rings. Misalignment of the rings results in
astigmatism which will degrade the image.
(5) Place the phase-shift test slide on the microscope stage and
focus on the lines. The analyst must see line set 3 and should see at
least parts of 4 and 5 but, not see line set 6 or 6. A microscope/
microscopist combination which does not pass this test may not be used.
6.6.2. Counting Fibers
(1) Place the prepared sample slide on the mechanical stage of the
microscope. Position the center of the wedge under the objective lens
and focus upon the sample.
(2) Start counting from one end of the wedge and progress along a
radial line to the other end (count in either direction from perimeter
to wedge tip). Select fields randomly, without looking into the
eyepieces, by slightly advancing the slide in one direction with the
mechanical stage control.
(3) Continually scan over a range of focal planes (generally the
upper 10 to 15 [micro]m of the filter surface) with the fine focus
control during each field count. Spend at least 5 to 15 seconds per
field.
(4) Most samples will contain asbestos fibers with fiber diameters
less than 1 [micro]m. Look carefully for faint fiber images. The small
diameter fibers will be very hard to see. However, they are an important
contribution to the total count.
(5) Count only fibers equal to or longer than 5 [micro]m. Measure
the length of curved fibers along the curve.
(6) Count fibers which have a length to width ratio of 3:1 or
greater.
(7) Count all the fibers in at least 20 fields. Continue counting
until either 100 fibers are counted or 100 fields have been viewed;
whichever occurs first. Count all the fibers in the final field.
(8) Fibers lying entirely within the boundary of the Walton-Beckett
graticule field shall receive a count of 1. Fibers crossing the boundary
once, having one end within the circle shall receive a count of \1/2\.
Do not count any fiber that crosses the graticule
[[Page 38]]
boundary more than once. Reject and do not count any other fibers even
though they may be visible outside the graticule area. If a fiber
touches the circle, it is considered to cross the line.
(9) Count bundles of fibers as one fiber unless individual fibers
can be clearly identified and each individual fiber is clearly not
connected to another counted fiber. See Figure 1 for counting
conventions.
(10) Record the number of fibers in each field in a consistent way
such that filter non-uniformity can be assessed.
(11) Regularly check phase ring alignment.
(12) When an agglomerate (mass of material) covers more than 25% of
the field of view, reject the field and select another. Do not include
it in the number of fields counted.
(13) Perform a ``blind recount'' of 1 in every 10 filter wedges
(slides). Re-label the slides using a person other than the original
counter.
6.7. Fiber Identification
As previously mentioned in Section 1.3., PCM does not provide
positive confirmation of asbestos fibers. Alternate differential
counting techniques should be used if discrimination is desirable.
Differential counting may include primary discrimination based on
morphology, polarized light analysis of fibers, or modification of PCM
data by Scanning Electron or Transmission Electron Microscopy.
A great deal of experience is required to routinely and correctly
perform differential counting. It is discouraged unless it is legally
necessary. Then, only if a fiber is obviously not asbestos should it be
excluded from the count. Further discussion of this technique can be
found in reference 8.10.
If there is a question whether a fiber is asbestos or not, follow
the rule:
``WHEN IN DOUBT, COUNT.''
6.8. Analytical Recommendations--Quality Control System
6.8.1. All individuals performing asbestos analysis must have taken
the NIOSH course for sampling and evaluating airborne asbestos or an
equivalent course.
6.8.2. Each laboratory engaged in asbestos counting shall set up a
slide trading arrangement with at least two other laboratories in order
to compare performance and eliminate inbreeding of error. The slide
exchange occurs at least semiannually. The round robin results shall be
posted where all analysts can view individual analyst's results.
6.8.3. Each laboratory engaged in asbestos counting shall
participate in the Proficiency Analytical Testing Program, the Asbestos
Analyst Registry or equivalent.
6.8.4. Each analyst shall select and count prepared slides from a
``slide bank''. These are quality assurance counts. The slide bank shall
be prepared using uniformly distributed samples taken from the workload.
Fiber densities should cover the entire range routinely analyzed by the
laboratory. These slides are counted blind by all counters to establish
an original standard deviation. This historical distribution is compared
with the quality assurance counts. A counter must have 95% of all
quality control samples counted within three standard deviations of the
historical mean. This count is then integrated into a new historical
mean and standard deviation for the slide.
The analyses done by the counters to establish the slide bank may be
used for an interim quality control program if the data are treated in a
proper statistical fashion.
7. Calculations
7.1. Calculate the estimated airborne asbestos fiber concentration
on the filter sample using the following formula:
where:
AC = Airborne fiber concentration
[GRAPHIC] [TIFF OMITTED] TR10AU94.000
FB = Total number of fibers greater than 5 [micro]m counted
FL = Total number of fields counted on the filter
BFB = Total number of fibers greater than 5 [micro]m counted in the
blank
BFL = Total number of fields counted on the blank
ECA = Effective collecting area of filter (385 mm\2\ nominal for a 25-mm
filter.)
FR = Pump flow rate (L/min)
MFA = Microscope count field area (mm\2\). This is 0.00785 mm\2\ for a
Walton-Beckett Graticule.
T = Sample collection time (min)
1,000 = Conversion of L to cc
Note: The collection area of a filter is seldom equal to 385 mm\2\.
It is appropriate for laboratories to routinely monitor the exact
diameter using an inside micrometer. The collection area is calculated
according to the formula:
Area = [pi](d/2)\2\
7.2. Short-cut Calculation
Since a given analyst always has the same interpupillary distance,
the number of fields per filter for a particular analyst will remain
constant for a given size filter. The field size for that analyst is
constant (i.e. the analyst is using an assigned microscope and is not
changing the reticle).
For example, if the exposed area of the filter is always 385 mm\2\
and the size of the field
[[Page 39]]
is always 0.00785 mm\2\, the number of fields per filter will always be
49,000. In addition it is necessary to convert liters of air to cc.
These three constants can then be combined such that ECA/(1,000 x
MFA)=49. The previous equation simplifies to:
[GRAPHIC] [TIFF OMITTED] TR10AU94.001
7.3. Recount Calculations
As mentioned in step 13 of Section 6.6.2., a ``blind recount'' of
10% of the slides is performed. In all cases, differences will be
observed between the first and second counts of the same filter wedge.
Most of these differences will be due to chance alone, that is, due to
the random variability (precision) of the count method. Statistical
recount criteria enables one to decide whether observed differences can
be explained due to chance alone or are probably due to systematic
differences between analysts, microscopes, or other biasing factors.
The following recount criterion is for a pair of counts that
estimate AC in fibers/cc. The criterion is given at the type-I error
level. That is, there is 5% maximum risk that we will reject a pair of
counts for the reason that one might be biased, when the large observed
difference is really due to chance.
Reject a pair of counts if:
[GRAPHIC] [TIFF OMITTED] TR29JN95.000
Where:
AC1 = lower estimated airborne fiber concentration
AC2 = higher estimated airborne fiber concentration
ACavg = average of the two concentration estimates
CVFB = CV for the average of the two concentration estimates
If a pair of counts are rejected by this criterion then, recount the
rest of the filters in the submitted set. Apply the test and reject any
other pairs failing the test. Rejection shall include a memo to the
industrial hygienist stating that the sample failed a statistical test
for homogeneity and the true air concentration may be significantly
different than the reported value.
7.4. Reporting Results
Report results to the industrial hygienist as fibers/cc. Use two
significant figures. If multiple analyses are performed on a sample, an
average of the results is to be reported unless any of the results can
be rejected for cause.
8. References
8.1. Dreesen, W.C., et al, U.S. Public Health Service: A Study of
Asbestosis in the Asbestos Textile Industry, (Public Health Bulletin No.
241), US Treasury Dept., Washington, DC, 1938.
8.2. Asbestos Research Council: The Measurement of Airborne Asbestos
Dust by the Membrane Filter Method (Technical Note), Asbestos Research
Council, Rockdale, Lancashire, Great Britain, 1969.
8.3. Bayer, S.G., Zumwalde, R.D., Brown, T.A., Equipment and
Procedure for Mounting Millipore Filters and Counting Asbestos Fibers by
Phase Contrast Microscopy, Bureau of Occupational Health, U.S. Dept. of
Health, Education and Welfare, Cincinnati, OH, 1969.
8.4. NIOSH Manual of Analytical Methods, 2nd ed., Vol. 1 (DHEW/NIOSH
Pub. No. 77-157-A). National Institute for Occupational Safety and
Health, Cincinnati, OH, 1977. pp. 239-1-239-21.
8.5. Asbestos, Code of Federal Regulations 29 CFR 1910.1001. 1971.
8.6. Occupational Exposure to Asbestos, Tremolite, Anthophyllite,
and Actinolite. Final Rule, Federal Register 51:119 (20 June 1986).
pp.22612-22790.
8.7. Asbestos, Tremolite, Anthophyllite, and Actinolite, Code of
Federal Regulations 1910.1001. 1988. pp 711-752.
8.8. Criteria for a Recommended Standard--Occupational Exposure to
Asbestos (DHEW/NIOSH Pub. No. HSM 72-10267), National Institute for
Occupational Safety and Health NIOSH, Cincinnati,OH, 1972. pp. III-1-
III-24.
8.9. Leidel, N.A., Bayer,S.G., Zumwalde, R.D.,Busch, K.A., USPHS/
NIOSH Membrane Filter Method for Evaluating Airborne Asbestos Fibers
(DHEW/NIOSH Pub. No. 79-127). National Institute for Occupational Safety
and Health, Cincinnati, OH, 1979.
8.10. Dixon, W.C., Applications of Optical Microscopy in Analysis of
Asbestos and Quartz, Analytical Techniques in Occupational Health
Chemistry, edited by D.D. Dollberg and A.W. Verstuyft. Wash. DC:
American Chemical Society, (ACS Symposium Series 120) 1980. pp. 13-41.
Quality Control
The OSHA asbestos regulations require each laboratory to establish a
quality control program. The following is presented as an example of how
the OSHA-SLTC constructed its internal CV curve as part of meeting this
requirement. Data is from 395 samples collected during OSHA compliance
inspections and analyzed from October 1980 through April 1986.
[[Page 40]]
Each sample was counted by 2 to 5 different counters independently
of one another. The standard deviation and the CV statistic was
calculated for each sample. This data was then plotted on a graph of CV
vs. fibers/mm\2\. A least squares regression was performed using the
following equation:
CV =
antilog110[A(log10(x))\2\+B(log10(x)
)+C]
where:
x = the number of fibers/mm\2\
Application of least squares gave:
A = 0.182205
B = -0.973343
C = 0.327499
Using these values, the equation becomes:
CV = antilog10 [0.182205(log10 (x))\2\-
0.973343(log10 (x))+0.327499]
Sampling Pump Flow Rate Corrections
This correction is used if a difference greater than 5% in ambient
temperature and/or pressure is noted between calibration and sampling
sites and the pump does not compensate for the differences.
[GRAPHIC] [TIFF OMITTED] TR10AU94.003
Where:
Qact = actual flow rate
Qcal = calibrated flow rate (if a rotameter was used, the
rotameter value)
Pcal = uncorrected air pressure at calibration
Pact = uncorrected air pressure at sampling site
Tact = temperature at sampling site (K)
Tcal = temperature at calibration (K)
Walton-Beckett Graticule
When ordering the Graticule for asbestos counting, specify the exact
disc diameter needed to fit the ocular of the microscope and the
diameter (mm) of the circular counting area. Instructions for measuring
the dimensions necessary are listed:
(1) Insert any available graticule into the focusing eyepiece and
focus so that the graticule lines are sharp and clear.
(2) Align the microscope.
(3) Place a stage micrometer on the microscope object stage and
focus the microscope on the graduated lines.
(4) Measure the magnified grid length, PL ([micro]m), using the
stage micrometer.
(5) Remove the graticule from the microscope and measure its actual
grid length, AL (mm). This can be accomplished by using a mechanical
stage fitted with verniers, or a jeweler's loupe with a direct reading
scale.
(6) Let D=100 [micro]m. Calculate the circle diameter, dc
(mm), for the Walton-Beckett graticule and specify the diameter when
making a purchase:
[GRAPHIC] [TIFF OMITTED] TR10AU94.004
Example: If PL=108 [micro]m, AL=2.93 mm and D=100 [micro]m, then,
[GRAPHIC] [TIFF OMITTED] TR10AU94.005
(7) Each eyepiece-objective-reticle combination on the microscope
must be calibrated. Should any of the three be changed (by zoom
adjustment, disassembly, replacement, etc.), the combination must be
recalibrated. Calibration may change if interpupillary distance is
changed. Measure the field diameter, D (acceptable range: 1002 [micro]m) with a stage micrometer upon receipt of the
graticule from the manufacturer. Determine the field area (mm\2\).
Field Area=[Delta](D/2)\2\
If D=100 [micro]m=0.1 mm, then
Field Area=[Delta](0.1 mm/2)\2\=0.00785 mm\2\
The Graticule is available from: Graticules Ltd., Morley Road,
Tonbridge TN9 IRN, Kent, England (Telephone 011-44-732-359061). Also
available from PTR Optics Ltd., 145 Newton Street, Waltham, MA 02154
[telephone (617) 891-6000] or McCrone Accessories and Components, 2506
S. Michigan Ave., Chicago, IL 60616 [phone (312)-842-7100]. The
graticule is custom made for each microscope.
Counts for the Fibers in the Figure
------------------------------------------------------------------------
Structure No. Count Explanation
------------------------------------------------------------------------
1 to 6...................... 1 Single fibers all contained
within the circle.
7........................... \1/2\ Fiber crosses circle once.
8........................... 0 Fiber too short.
9........................... 2 Two crossing fibers.
10........................... 0 Fiber outside graticule.
11........................... 0 Fiber crosses graticule twice.
12........................... \1/2\ Although split, fiber only
crosses once.
------------------------------------------------------------------------
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Appendix C toSec. 1910.1001 [Reserved]
Appendix D toSec. 1910.1001--Medical Questionnaires; Mandatory
This mandatory appendix contains the medical questionnaires that
must be administered to all employees who are exposed to asbestos above
the permissible exposure limit, and who will therefore be included in
their employer's medical surveillance program. Part 1 of the appendix
contains the Initial Medical Questionnaire, which must be obtained for
all new hires who will be covered by the medical surveillance
requirements. Part 2 includes the abbreviated Periodical Medical
Questionnaire, which must be administered to all employees who are
provided periodic medical examinations under the medical surveillance
provisions of the standard.
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Appendix E toSec. 1910.1001--Interpretation and Classification of
Chest Roentgenograms--Mandatory
(a) Chest roentgenograms shall be interpreted and classified in
accordance with a professionally accepted Classification system and
recorded on an interpretation form following the format of the CDC/NIOSH
(M) 2.8 form. As a minimum, the content within the bold lines of this
form (items 1 though 4) shall be included. This form is not to be
submitted to NIOSH.
(b) Roentgenograms shall be interpreted and classified only by a B-
reader, a board eligible/certified radiologist, or an experienced
physician with known expertise in pneumoconioses.
(c) All interpreters, whenever interpreting chest roentgenograms
made under this section, shall have immediately available for reference
a complete set of the ILO-U/C International Classification of
Radiographs for Pneumoconioses, 1980.
Appendix F toSec. 1910.1001--Work Practices and Engineering Controls
for Automotive Brake and Clutch Inspection, Disassembly, Repair and
Assembly--Mandatory
This mandatory appendix specifies engineering controls and work
practices that must be implemented by the employer during automotive
brake and clutch inspection, disassembly, repair, and assembly
operations. Proper use of these engineering controls and work practices
by trained employees will reduce employees' asbestos exposure below the
permissible exposure level during clutch and brake inspection,
disassembly, repair, and assembly operations. The employer shall
institute engineering controls and work practices using either the
method set forth in paragraph [A] or paragraph [B] of this appendix, or
any other method which the employer can demonstrate to be equivalent in
terms of reducing employee exposure to asbestos as defined and which
meets the requirements described in paragraph [C] of
[[Page 54]]
this appendix, for those facilities in which no more than 5 pairs of
brakes or 5 clutches are inspected, disassembled, reassembled and/or
repaired per week, the method set forth in paragraph [D] of this
appendix may be used:
[A] Negative Pressure Enclosure/HEPA Vacuum System Method
(1) The brake and clutch inspection, disassembly, repair, and
assembly operations shall be enclosed to cover and contain the clutch or
brake assembly and to prevent the release of asbestos fibers into the
worker's breathing zone.
(2) The enclosure shall be sealed tightly and thoroughly inspected
for leaks before work begins on brake and clutch inspection,
disassembly, repair, and assembly.
(3) The enclosure shall be such that the worker can clearly see the
operation and shall provide impermeable sleeves through which the worker
can handle the brake and clutch inspection, disassembly, repair and
assembly. The integrity of the sleeves and ports shall be examined
before work begins.
(4) A HEPA-filtered vacuum shall be employed to maintain the
enclosure under negative pressure throughout the operation. Compressed-
air may be used to remove asbestos fibers or particles from the
enclosure.
(5) The HEPA vacuum shall be used first to loosen the asbestos
containing residue from the brake and clutch parts and then to evacuate
the loosened asbestos containing material from the enclosure and capture
the material in the vacuum filter.
(6) The vacuum's filter, when full, shall be first wetted with a
fine mist of water, then removed and placed immediately in an
impermeable container, labeled according to paragraph (j)(5) of this
section and disposed of according to paragraph (k) of this section.
(7) Any spills or releases of asbestos containing waste material
from inside of the enclosure or vacuum hose or vacuum filter shall be
immediately cleaned up and disposed of according to paragraph (k) of
this section.
[B] Low Pressure/Wet Cleaning Method
(1) A catch basin shall be placed under the brake assembly,
positioned to avoid splashes and spills.
(2) The reservoir shall contain water containing an organic solvent
or wetting agent. The flow of liquid shall be controlled such that the
brake assembly is gently flooded to prevent the asbestos-containing
brake dust from becoming airborne.
(3) The aqueous solution shall be allowed to flow between the brake
drum and brake support before the drum is removed.
(4) After removing the brake drum, the wheel hub and back of the
brake assembly shall be thoroughly wetted to suppress dust.
(5) The brake support plate, brake shoes and brake components used
to attach the brake shoes shall be thoroughly washed before removing the
old shoes.
(6) In systems using filters, the filters, when full, shall be first
wetted with a fine mist of water, then removed and placed immediately in
an impermeable container, labeled according to paragraph (j)(4) of this
section and disposed of according to paragraph (k) of this section.
(7) Any spills of asbestos-containing aqueous solution or any
asbestos-containing waste material shall be cleaned up immediately and
disposed of according to paragraph (k) of this section.
(8) The use of dry brushing during low pressure/wet cleaning
operations is prohibited.
[C] Equivalent Methods
An equivalent method is one which has sufficient written detail so
that it can be reproduced and has been demonstrated that the exposures
resulting from the equivalent method are equal to or less than the
exposures which would result from the use of the method described in
paragraph [A] of this appendix. For purposes of making this comparison,
the employer shall assume that exposures resulting from the use of the
method described in paragraph [A] of this appendix shall not exceed
0.016 f/cc, as measured by the OSHA reference method and as averaged
over at least 18 personal samples.
[D] Wet Method.
(1) A spray bottle, hose nozzle, or other implement capable of
delivering a fine mist of water or amended water or other delivery
system capable of delivering water at low pressure, shall be used to
first thoroughly wet the brake and clutch parts. Brake and clutch
components shall then be wiped clean with a cloth.
(2) The cloth shall be placed in an impermeable container, labelled
according to paragraph (j)(4) of this section and then disposed of
according to paragraph (k) of this section, or the cloth shall be
laundered in a way to prevent the release of asbestos fibers in excess
of 0.1 fiber per cubic centimeter of air.
(3) Any spills of solvent or any asbestos containing waste material
shall be cleaned up immediately according to paragraph (k) of this
section.
(4) The use of dry brushing during the wet method operations is
prohibited.
Appendix G toSec. 1910.1001--Substance Technical Information for
Asbestos--Non-Mandatory
I. Substance Identification
A. Substance: ``Asbestos'' is the name of a class of magnesium-
silicate minerals that
[[Page 55]]
occur in fibrous form. Minerals that are included in this group are
chrysotile, crocidolite, amosite, tremolite asbestos, anthophyllite
asbestos, and actinolite asbestos.
B. Asbestos is used in the manufacture of heat-resistant clothing,
automative brake and clutch linings, and a variety of building materials
including floor tiles, roofing felts, ceiling tiles, asbestos-cement
pipe and sheet, and fire-resistant drywall. Asbestos is also present in
pipe and boiler insulation materials, and in sprayed-on materials
located on beams, in crawlspaces, and between walls.
C. The potential for a product containing asbestos to release
breatheable fibers depends on its degree of friability. Friable means
that the material can be crumbled with hand pressure and is therefore
likely to emit fibers. The fibrous or fluffy sprayed-on materials used
for fireproofing, insulation, or sound proofing are considered to be
friable, and they readily release airborne fibers if disturbed.
Materials such as vinyl-asbestos floor tile or roofing felts are
considered nonfriable and generally do not emit airborne fibers unless
subjected to sanding or sawing operations. Asbestos-cement pipe or sheet
can emit airborne fibers if the materials are cut or sawed, or if they
are broken during demolition operations.
D. Permissible exposure: Exposure to airborne asbestos fibers may
not exceed 0.2 fibers per cubic centimeter of air (0.1 f/cc) averaged
over the 8-hour workday.
II. Health Hazard Data
A. Asbestos can cause disabling respiratory disease and various
types of cancers if the fibers are inhaled. Inhaling or ingesting fibers
from contaminated clothing or skin can also result in these diseases.
The symptoms of these diseases generally do not appear for 20 or more
years after initial exposure.
B. Exposure to asbestos has been shown to cause lung cancer,
mesothelioma, and cancer of the stomach and colon. Mesothelioma is a
rare cancer of the thin membrane lining of the chest and abdomen.
Symptoms of mesothelioma include shortness of breath, pain in the walls
of the chest, and/or abdominal pain.
III. Respirators and Protective Clothing
A. Respirators: You are required to wear a respirator when
performing tasks that result in asbestos exposure that exceeds the
permissible exposure limit (PEL) of 0.1 f/cc. These conditions can occur
while your employer is in the process of installing engineering controls
to reduce asbestos exposure, or where engineering controls are not
feasible to reduce asbestos exposure. Air-purifying respirators equipped
with a high-efficiency particulate air (HEPA) filter can be used where
airborne asbestos fiber concentrations do not exceed 2 f/cc; otherwise,
air-supplied, positive-pressure, full facepiece respirators must be
used. Disposable respirators or dust masks are not permitted to be used
for asbestos work. For effective protection, respirators must fit your
face and head snugly. Your employer is required to conduct fit tests
when you are first assigned a respirator and every 6 months thereafter.
Respirators should not be loosened or removed in work situations where
their use is required.
B. Protective clothing: You are required to wear protective clothing
in work areas where asbestos fiber concentrations exceed the permissible
exposure limit.
IV. Disposal Procedures and Cleanup
A. Wastes that are generated by processes where asbestos is present
include:
1. Empty asbestos shipping containers.
2. Process wastes such as cuttings, trimmings, or reject material.
3. Housekeeping waste from sweeping or vacuuming.
4. Asbestos fireproofing or insulating material that is removed from
buildings.
5. Building products that contain asbestos removed during building
renovation or demolition.
6. Contaminated disposable protective clothing.
B. Empty shipping bags can be flattened under exhaust hoods and
packed into airtight containers for disposal. Empty shipping drums are
difficult to clean and should be sealed.
C. Vacuum bags or disposable paper filters should not be cleaned,
but should be sprayed with a fine water mist and placed into a labeled
waste container.
D. Process waste and housekeeping waste should be wetted with water
or a mixture of water and surfactant prior to packaging in disposable
containers.
E. Material containing asbestos that is removed from buildings must
be disposed of in leak-tight 6-mil thick plastic bags, plastic-lined
cardboard containers, or plastic-lined metal containers. These wastes,
which are removed while wet, should be sealed in containers before they
dry out to minimize the release of asbestos fibers during handling.
V. Access to Information
A. Each year, your employer is required to inform you of the
information contained in this standard and appendices for asbestos. In
addition, your employer must instruct you in the proper work practices
for handling materials containing asbestos, and the correct use of
protective equipment.
B. Your employer is required to determine whether you are being
exposed to asbestos. You or your representative has the right to observe
employee measurements and to
[[Page 56]]
record the results obtained. Your employer is required to inform you of
your exposure, and, if you are exposed above the permissible limit, he
or she is required to inform you of the actions that are being taken to
reduce your exposure to within the permissible limit.
C. Your employer is required to keep records of your exposures and
medical examinations. These exposure records must be kept for at least
thirty (30) years. Medical records must be kept for the period of your
employment plus thirty (30) years.
D. Your employer is required to release your exposure and medical
records to your physician or designated representative upon your written
request.
Appendix H toSec. 1910.1001--Medical Surveillance Guidelines for
Asbestos Non-Mandatory
I. Route of Entry Inhalation, Ingestion
II. Toxicology
Clinical evidence of the adverse effects associated with exposure to
asbestos is present in the form of several well-conducted
epidemiological studies of occupationally exposed workers, family
contacts of workers, and persons living near asbestos mines. These
studies have shown a definite association between exposure to asbestos
and an increased incidence of lung cancer, pleural and peritoneal
mesothelioma, gastrointestinal cancer, and asbestosis. The latter is a
disabling fibrotic lung disease that is caused only by exposure to
asbestos. Exposure to asbestos has also been associated with an
increased incidence of esophageal, kidney, laryngeal, pharyngeal, and
buccal cavity cancers. As with other known chronic occupational
diseases, disease associated with asbestos generally appears about 20
years following the first occurrence of exposure: There are no known
acute effects associated with exposure to asbestos.
Epidemiological studies indicate that the risk of lung cancer among
exposed workers who smoke cigarettes is greatly increased over the risk
of lung cancer among non-exposed smokers or exposed nonsmokers. These
studies suggest that cessation of smoking will reduce the risk of lung
cancer for a person exposed to asbestos but will not reduce it to the
same level of risk as that existing for an exposed worker who has never
smoked.
III. Signs and Symptoms of Exposure-Related Disease
The signs and symptoms of lung cancer or gastrointestinal cancer
induced by exposure to asbestos are not unique, except that a chest X-
ray of an exposed patient with lung cancer may show pleural plaques,
pleural calcification, or pleural fibrosis. Symptoms characteristic of
mesothelioma include shortness of breath, pain in the walls of the
chest, or abdominal pain. Mesothelioma has a much longer latency period
compared with lung cancer (40 years versus 15-20 years), and
mesothelioma is therefore more likely to be found among workers who were
first exposed to asbestos at an early age. Mesothelioma is always fatal.
Asbestosis is pulmonary fibrosis caused by the accumulation of
asbestos fibers in the lungs. Symptoms include shortness of breath,
coughing, fatigue, and vague feelings of sickness. When the fibrosis
worsens, shortness of breath occurs even at rest. The diagnosis of
asbestosis is based on a history of exposure to asbestos, the presence
of characteristic radiologic changes, end-inspiratory crackles (rales),
and other clinical features of fibrosing lung disease. Pleural plaques
and thickening are observed on X-rays taken during the early stages of
the disease. Asbestosis is often a progressive disease even in the
absence of continued exposure, although this appears to be a highly
individualized characteristic. In severe cases, death may be caused by
respiratory or cardiac failure.
IV. Surveillance and Preventive Considerations
As noted above, exposure to asbestos has been linked to an increased
risk of lung cancer, mesothelioma, gastrointestinal cancer, and
asbestosis among occupationally exposed workers. Adequate screening
tests to determine an employee's potential for developing serious
chronic diseases, such as cancer, from exposure to asbestos do not
presently exist. However, some tests, particularly chest X-rays and
pulmonary function tests, may indicate that an employee has been
overexposed to asbestos increasing his or her risk of developing
exposure-related chronic diseases. It is important for the physician to
become familiar with the operating conditions in which occupational
exposure to asbestos is likely to occur. This is particularly important
in evaluating medical and work histories and in conducting physical
examinations. When an active employee has been identified as having been
overexposed to asbestos, measures taken by the employer to eliminate or
mitigate further exposure should also lower the risk of serious long-
term consequences.
The employer is required to institute a medical surveillance program
for all employees who are or will be exposed to asbestos at or above the
permissible exposure limit (0.1 fiber per cubic centimeter of air). All
examinations and procedures must be performed by or under the
supervision of a licensed physician, at a reasonable time and place, and
at no cost to the employee.
Although broad latitude is given to the physician in prescribing
specific tests to be
[[Page 57]]
included in the medical surveillance program, OSHA requires inclusion of
the following elements in the routine examination:
(i) Medical and work histories with special emphasis directed to
symptoms of the respiratory system, cardiovascular system, and digestive
tract.
(ii) Completion of the respiratory disease questionnaire contained
in appendix D.
(iii) A physical examination including a chest roentgenogram and
pulmonary function test that includes measurement of the employee's
forced vital capacity (FVC) and forced expiratory volume at one second
(FEV1).
(iv) Any laboratory or other test that the examining physician deems
by sound medical practice to be necessary.
The employer is required to make the prescribed tests available at
least annually to those employees covered; more often than specified if
recommended by the examining physician; and upon termination of
employment.
The employer is required to provide the physician with the following
information: A copy of this standard and appendices; a description of
the mployee's duties as they relate to asbestos exposure; the employee's
representative level of exposure to asbestos; a description of any
personal protective and respiratory equipment used; and information from
previous medical examinations of the affected employee that is not
otherwise available to the physician. Making this information available
to the physician will aid in the evaluation of the employee's health in
relation to assigned duties and fitness to wear personal protective
equipment, if required.
The employer is required to obtain a written opinion from the
examining physician containing the results of the medical examination;
the physician's opinion as to whether the employee has any detected
medical conditions that would place the employee at an increased risk of
exposure-related disease; any recommended limitations on the employee or
on the use of personal protective equipment; and a statement that the
employee has been informed by the physician of the results of the
medical examination and of any medical conditions related to asbestos
exposure that require further explanation or treatment. This written
opinion must not reveal specific findings or diagnoses unrelated to
exposure to asbestos, and a copy of the opinion must be provided to the
affected employee.
Appendix I toSec. 1910.1001--Smoking Cessation Program Information For
Asbestos--Non-Mandatory
The following organizations provide smoking cessation information
and program material.
1. The National Cancer Institute operates a toll-free Cancer
Information Service (CIS) with trained personnel to help you. Call 1-
800-4-CANCER* to reach the CIS office serving your area, or write:
Office of Cancer Communications, National Cancer Institute, National
Institutes of Health, Building 31, Room 10A24, Bethesda, Maryland 20892.
2. American Cancer Society, 3340 Peachtree Road, NE., Atlanta,
Georgia 30062, (404) 320-3333.
The American Cancer Society (ACS) is a voluntary organization
composed of 58 divisions and 3,100 local units. Through ``The Great
American Smokeout'' in November, the annual Cancer Crusade in April, and
numerous educational materials, ACS helps people learn about the health
hazards of smoking and become successful ex-smokers.
3. American Heart Association, 7320 Greenville Avenue, Dallas, Texas
75231, (214) 750-5300.
The American Heart Association (AHA) is a voluntary organization
with 130,000 members (physicians, scientists, and laypersons) in 55
state and regional groups. AHA produces a variety of publications and
audiovisual materials about the effects of smoking on the heart. AHA
also has developed a guidebook for incorporating a weight-control
component into smoking cessation programs.
4. American Lung Association, 1740 Broadway, New York, New York
10019, (212) 245-8000.
A voluntary organization of 7,500 members (physicians, nurses, and
laypersons), the American Lung Association (ALA) conducts numerous
public information programs about the health effect of smoking. ALA has
59 state and 85 local units. The organization actively supports
legislation and information campaigns for non-smokers' rights and
provides help for smokers who want to quit, for example, through
``Freedom From Smoking,'' a self-help smoking cessation program.
5. Office on Smoking and Health, U.S. Department of Health and,
Human Services, 5600 Fishers Lane, Park Building, Room 110, Rockville,
Maryland 20857.
The Office on Smoking and Health (OSH) is the Department of Health
and Human Services' lead agency in smoking control. OSH has sponsored
distribution of publications on smoking-realted topics, such as free
flyers on relapse after initial quitting, helping a friend or family
member quit smoking, the health hazards of smoking, and the effects of
parental smoking on teenagers.
*In Hawaii, on Oahu call 524-1234 (call collect from neighboring
islands),
Spanish-speaking staff members are available during daytime hours to
callers from the following areas: California, Florida, Georgia,
Illinois, New Jersey (area code 210), New York, and Texas. Consult your
local
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telephone directory for listings of local chapters.
Appendix J toSec. 1910.1001--Polarized Light Microscopy of Asbestos--
Non-Mandatory
Method number: ID-191
Matrix: Bulk
Collection Procedure
Collect approximately 1 to 2 grams of each type of material and
place into separate 20 mL scintillation vials.
Analytical Procedure
A portion of each separate phase is analyzed by gross examination,
phase-polar examination, and central stop dispersion microscopy.
Commercial manufacturers and products mentioned in this method are
for descriptive use only and do not constitute endorsements by USDOL-
OSHA. Similar products from other sources may be substituted.
1. Introduction
This method describes the collection and analysis of asbestos bulk
materials by light microscopy techniques including phase- polar
illumination and central-stop dispersion microscopy. Some terms unique
to asbestos analysis are defined below:
Amphibole: A family of minerals whose crystals are formed by long,
thin units which have two thin ribbons of double chain silicate with a
brucite ribbon in between. The shape of each unit is similar to an ``I
beam''. Minerals important in asbestos analysis include cummingtonite-
grunerite, crocidolite, tremolite-actinolite and anthophyllite.
Asbestos: A term for naturally occurring fibrous minerals. Asbestos
includes chrysotile, cummingtonite-grunerite asbestos (amosite),
anthophyllite asbestos, tremolite asbestos, crocidolite, actinolite
asbestos and any of these minerals which have been chemically treated or
altered. The precise chemical formulation of each species varies with
the location from which it was mined. Nominal compositions are listed:
Chrysotile.............................. Mg3 Si2 O5(OH)4
Crocidolite (Riebeckite asbestos)....... Na2 Fe3\2+\ Fe2\3+\ Si8
O22(OH)2
Cummingtonite-Grunerite asbestos (Mg,Fe)7 Si8 O22(OH)2
(Amosite)..............................
Tremolite-Actinolite asbestos........... Ca2(Mg,Fe)5 Si8 O22(OH)2
Anthophyllite asbestos.................. (Mg,Fe)7 Si8 O22(OH)2
Asbestos Fiber: A fiber of asbestos meeting the criteria for a
fiber. (See section 3.5.)
Aspect Ratio: The ratio of the length of a fiber to its diameter
usually defined as ``length : width'', e.g. 3:1.
Brucite: A sheet mineral with the composition Mg(OH)2.
Central Stop Dispersion Staining (microscope): This is a dark field
microscope technique that images particles using only light refracted by
the particle, excluding light that travels through the particle
unrefracted. This is usually accomplished with a McCrone objective or
other arrangement which places a circular stop with apparent aperture
equal to the objective aperture in the back focal plane of the
microscope.
Cleavage Fragments: Mineral particles formed by the comminution of
minerals, especially those characterized by relatively parallel sides
and moderate aspect ratio.
Differential Counting: The term applied to the practice of excluding
certain kinds of fibers from a phase contrast asbestos count because
they are not asbestos.
Fiber: A particle longer than or equal to 5 [micro]m with a length
to width ratio greater than or equal to 3:1. This may include cleavage
fragments. (see section 3.5 of this appendix).
Phase Contrast: Contrast obtained in the microscope by causing light
scattered by small particles to destructively interfere with unscattered
light, thereby enhancing the visibility of very small particles and
particles with very low intrinsic contrast.
Phase Contrast Microscope: A microscope configured with a phase mask
pair to create phase contrast. The technique which uses this is called
Phase Contrast Microscopy (PCM).
Phase-Polar Analysis: This is the use of polarized light in a phase
contrast microscope. It is used to see the same size fibers that are
visible in air filter analysis. Although fibers finer than 1 [micro]m
are visible, analysis of these is inferred from analysis of larger
bundles that are usually present.
Phase-Polar Microscope: The phase-polar microscope is a phase
contrast microscope which has an analyzer, a polarizer, a first order
red plate and a rotating phase condenser all in place so that the
polarized light image is enhanced by phase contrast.
Sealing Encapsulant: This is a product which can be applied,
preferably by spraying, onto an asbestos surface which will seal the
surface so that fibers cannot be released.
Serpentine: A mineral family consisting of minerals with the general
composition Mg3(Si2O5(OH)4 having the
magnesium in brucite layer over a silicate layer. Minerals important in
asbestos analysis included in this family are chrysotile, lizardite,
antigorite.
1.1. History
Light microscopy has been used for well over 100 years for the
determination of mineral species. This analysis is carried out
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using specialized polarizing microscopes as well as bright field
microscopes. The identification of minerals is an on-going process with
many new minerals described each year. The first recorded use of
asbestos was in Finland about 2500 B.C. where the material was used in
the mud wattle for the wooden huts the people lived in as well as
strengthening for pottery. Adverse health aspects of the mineral were
noted nearly 2000 years ago when Pliny the Younger wrote about the poor
health of slaves in the asbestos mines. Although known to be injurious
for centuries, the first modern references to its toxicity were by the
British Labor Inspectorate when it banned asbestos dust from the
workplace in 1898. Asbestosis cases were described in the literature
after the turn of the century. Cancer was first suspected in the mid
1930's and a causal link to mesothelioma was made in 1965. Because of
the public concern for worker and public safety with the use of this
material, several different types of analysis were applied to the
determination of asbestos content. Light microscopy requires a great
deal of experience and craft. Attempts were made to apply less
subjective methods to the analysis. X-ray diffraction was partially
successful in determining the mineral types but was unable to separate
out the fibrous portions from the non-fibrous portions. Also, the
minimum detection limit for asbestos analysis by X-ray diffraction (XRD)
is about 1%. Differential Thermal Analysis (DTA) was no more successful.
These provide useful corroborating information when the presence of
asbestos has been shown by microscopy; however, neither can determine
the difference between fibrous and non-fibrous minerals when both habits
are present. The same is true of Infrared Absorption (IR).
When electron microscopy was applied to asbestos analysis, hundreds
of fibers were discovered present too small to be visible in any light
microscope. There are two different types of electron microscope used
for asbestos analysis: Scanning Electron Microscope (SEM) and
Transmission Electron Microscope (TEM). Scanning Electron Microscopy is
useful in identifying minerals. The SEM can provide two of the three
pieces of information required to identify fibers by electron
microscopy: morphology and chemistry. The third is structure as
determined by Selected Area Electron Diffraction--SAED which is
performed in the TEM. Although the resolution of the SEM is sufficient
for very fine fibers to be seen, accuracy of chemical analysis that can
be performed on the fibers varies with fiber diameter in fibers of less
than 0.2 [micro]m diameter. The TEM is a powerful tool to identify
fibers too small to be resolved by light microscopy and should be used
in conjunction with this method when necessary. The TEM can provide all
three pieces of information required for fiber identification. Most
fibers thicker than 1 [micro]m can adequately be defined in the light
microscope. The light microscope remains as the best instrument for the
determination of mineral type. This is because the minerals under
investigation were first described analytically with the light
microscope. It is inexpensive and gives positive identification for most
samples analyzed. Further, when optical techniques are inadequate, there
is ample indication that alternative techniques should be used for
complete identification of the sample.
1.2. Principle
Minerals consist of atoms that may be arranged in random order or in
a regular arrangement. Amorphous materials have atoms in random order
while crystalline materials have long range order. Many materials are
transparent to light, at least for small particles or for thin sections.
The properties of these materials can be investigated by the effect that
the material has on light passing through it. The six asbestos minerals
are all crystalline with particular properties that have been identified
and cataloged. These six minerals are anisotropic. They have a regular
array of atoms, but the arrangement is not the same in all directions.
Each major direction of the crystal presents a different regularity.
Light photons travelling in each of these main directions will encounter
different electrical neighborhoods, affecting the path and time of
travel. The techniques outlined in this method use the fact that light
traveling through fibers or crystals in different directions will behave
differently, but predictably. The behavior of the light as it travels
through a crystal can be measured and compared with known or determined
values to identify the mineral species. Usually, Polarized Light
Microscopy (PLM) is performed with strain-free objectives on a bright-
field microscope platform. This would limit the resolution of the
microscope to about 0.4 [micro]m. Because OSHA requires the counting and
identification of fibers visible in phase contrast, the phase contrast
platform is used to visualize the fibers with the polarizing elements
added into the light path. Polarized light methods cannot identify
fibers finer than about 1 [micro]m in diameter even though they are
visible. The finest fibers are usually identified by inference from the
presence of larger, identifiable fiber bundles. When fibers are present,
but not identifiable by light microscopy, use either SEM or TEM to
determine the fiber identity.
1.3. Advantages and Disadvantages
The advantages of light microcopy are:
(a) Basic identification of the materials was first performed by
light microscopy and gross analysis. This provides a large base of
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published information against which to check analysis and analytical
technique.
(b) The analysis is specific to fibers. The minerals present can
exist in asbestiform, fibrous, prismatic, or massive varieties all at
the same time. Therefore, bulk methods of analysis such as X-ray
diffraction, IR analysis, DTA, etc. are inappropriate where the material
is not known to be fibrous.
(c) The analysis is quick, requires little preparation time, and can
be performed on-site if a suitably equipped microscope is available.
The disadvantages are:
(a) Even using phase-polar illumination, not all the fibers present
may be seen. This is a problem for very low asbestos concentrations
where agglomerations or large bundles of fibers may not be present to
allow identification by inference.
(b) The method requires a great degree of sophistication on the part
of the microscopist. An analyst is only as useful as his mental catalog
of images. Therefore, a microscopist's accuracy is enhanced by
experience. The mineralogical training of the analyst is very important.
It is the basis on which subjective decisions are made.
(c) The method uses only a tiny amount of material for analysis.
This may lead to sampling bias and false results (high or low). This is
especially true if the sample is severely inhomogeneous.
(d) Fibers may be bound in a matrix and not distinguishable as
fibers so identification cannot be made.
1.4. Method Performance
1.4.1. This method can be used for determination of asbestos content
from 0 to 100% asbestos. The detection limit has not been adequately
determined, although for selected samples, the limit is very low,
depending on the number of particles examined. For mostly homogeneous,
finely divided samples, with no difficult fibrous interferences, the
detection limit is below 1%. For inhomogeneous samples (most samples),
the detection limit remains undefined. NIST has conducted proficiency
testing of laboratories on a national scale. Although each round is
reported statistically with an average, control limits, etc., the
results indicate a difficulty in establishing precision especially in
the low concentration range. It is suspected that there is significant
bias in the low range especially near 1%. EPA tried to remedy this by
requiring a mandatory point counting scheme for samples less than 10%.
The point counting procedure is tedious, and may introduce significant
biases of its own. It has not been incorporated into this method.
1.4.2. The precision and accuracy of the quantitation tests
performed in this method are unknown. Concentrations are easier to
determine in commercial products where asbestos was deliberately added
because the amount is usually more than a few percent. An analyst's
results can be ``calibrated'' against the known amounts added by the
manufacturer. For geological samples, the degree of homogeneity affects
the precision.
1.4.3. The performance of the method is analyst dependent. The
analyst must choose carefully and not necessarily randomly the portions
for analysis to assure that detection of asbestos occurs when it is
present. For this reason, the analyst must have adequate training in
sample preparation, and experience in the location and identification of
asbestos in samples. This is usually accomplished through substantial
on-the-job training as well as formal education in mineralogy and
microscopy.
1.5. Interferences
Any material which is long, thin, and small enough to be viewed
under the microscope can be considered an interference for asbestos.
There are literally hundreds of interferences in workplaces. The
techniques described in this method are normally sufficient to eliminate
the interferences. An analyst's success in eliminating the interferences
depends on proper training.
Asbestos minerals belong to two mineral families: the serpentines
and the amphiboles. In the serpentine family, the only common fibrous
mineral is chrysotile. Occasionally, the mineral antigorite occurs in a
fibril habit with morphology similar to the amphiboles. The amphibole
minerals consist of a score of different minerals of which only five are
regulated by federal standard: amosite, crocidolite, anthophyllite
asbestos, tremolite asbestos and actinolite asbestos. These are the only
amphibole minerals that have been commercially exploited for their
fibrous properties; however, the rest can and do occur occasionally in
asbestiform habit.
In addition to the related mineral interferences, other minerals
common in building material may present a problem for some
microscopists: gypsum, anhydrite, brucite, quartz fibers, talc fibers or
ribbons, wollastonite, perlite, attapulgite, etc. Other fibrous
materials commonly present in workplaces are: fiberglass, mineral wool,
ceramic wool, refractory ceramic fibers, kevlar, nomex, synthetic
fibers, graphite or carbon fibers, cellulose (paper or wood) fibers,
metal fibers, etc.
Matrix embedding material can sometimes be a negative interference.
The analyst may not be able to easily extract the fibers from the matrix
in order to use the method. Where possible, remove the matrix before the
analysis, taking careful note of the loss of weight. Some common matrix
materials are: vinyl, rubber, tar, paint, plant fiber, cement, and
epoxy. A further negative interference is that the asbestos fibers
themselves may be either too small to be seen in Phase contrast
Microscopy (PCM) or of a very low
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fibrous quality, having the appearance of plant fibers. The analyst's
ability to deal with these materials increases with experience.
1.6. Uses and Occupational Exposure
Asbestos is ubiquitous in the environment. More than 40% of the land
area of the United States is composed of minerals which may contain
asbestos. Fortunately, the actual formation of great amounts of asbestos
is relatively rare. Nonetheless, there are locations in which
environmental exposure can be severe such as in the Serpentine Hills of
California.
There are thousands of uses for asbestos in industry and the home.
Asbestos abatement workers are the most current segment of the
population to have occupational exposure to great amounts of asbestos.
If the material is undisturbed, there is no exposure. Exposure occurs
when the asbestos-containing material is abraded or otherwise disturbed
during maintenance operations or some other activity. Approximately 95%
of the asbestos in place in the United States is chrysotile.
Amosite and crocidolite make up nearly all the difference. Tremolite
and anthophyllite make up a very small percentage. Tremolite is found in
extremely small amounts in certain chrysotile deposits. Actinolite
exposure is probably greatest from environmental sources, but has been
identified in vermiculite containing, sprayed-on insulating materials
which may have been certified as asbestos-free.
1.7. Physical and Chemical Properties
The nominal chemical compositions for the asbestos minerals were
given in Section 1. Compared to cleavage fragments of the same minerals,
asbestiform fibers possess a high tensile strength along the fiber axis.
They are chemically inert, non- combustible, and heat resistant. Except
for chrysotile, they are insoluble in Hydrochloric acid (HCl).
Chrysotile is slightly soluble in HCl. Asbestos has high electrical
resistance and good sound absorbing characteristics. It can be woven
into cables, fabrics or other textiles, or matted into papers, felts,
and mats.
1.8. Toxicology (This section is for Information Only and Should Not Be
Taken as OSHA Policy)
Possible physiologic results of respiratory exposure to asbestos are
mesothelioma of the pleura or peritoneum, interstitial fibrosis,
asbestosis, pneumoconiosis, or respiratory cancer. The possible
consequences of asbestos exposure are detailed in the NIOSH Criteria
Document or in the OSHA Asbestos Standards 29 CFR 1910.1001 and 29 CFR
1926.1101 and 29 CFR 1915.1001.
2. Sampling Procedure
2.1. Equipment for Sampling
(a) Tube or cork borer sampling device
(b) Knife
(c) 20 mL scintillation vial or similar vial
(d) Sealing encapsulant
2.2. Safety Precautions
Asbestos is a known carcinogen. Take care when sampling. While in an
asbestos-containing atmosphere, a properly selected and fit-tested
respirator should be worn. Take samples in a manner to cause the least
amount of dust. Follow these general guidelines:
(a) Do not make unnecessary dust.
(b) Take only a small amount (1 to 2 g).
(c) Tightly close the sample container.
(d) Use encapsulant to seal the spot where the sample was taken, if
necessary.
2.3. Sampling Procedure
Samples of any suspect material should be taken from an
inconspicuous place. Where the material is to remain, seal the sampling
wound with an encapsulant to eliminate the potential for exposure from
the sample site. Microscopy requires only a few milligrams of material.
The amount that will fill a 20 mL scintillation vial is more than
adequate. Be sure to collect samples from all layers and phases of
material. If possible, make separate samples of each different phase of
the material. This will aid in determining the actual hazard. DO NOT USE
ENVELOPES, PLASTIC OR PAPER BAGS OF ANY KIND TO COLLECT SAMPLES. The use
of plastic bags presents a contamination hazard to laboratory personnel
and to other samples. When these containers are opened, a bellows effect
blows fibers out of the container onto everything, including the person
opening the container.
If a cork-borer type sampler is available, push the tube through the
material all the way, so that all layers of material are sampled. Some
samplers are intended to be disposable. These should be capped and sent
to the laboratory. If a non-disposable cork borer is used, empty the
contents into a scintillation vial and send to the laboratory.
Vigorously and completely clean the cork borer between samples.
2.4 Shipment
Samples packed in glass vials must not touch or they might break in
shipment.
(a) Seal the samples with a sample seal over the end to guard
against tampering and to identify the sample.
(b) Package the bulk samples in separate packages from the air
samples. They may cross-contaminate each other and will invalidate the
results of the air samples.
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(c) Include identifying paperwork with the samples, but not in
contact with the suspected asbestos.
(d) To maintain sample accountability, ship the samples by certified
mail, overnight express, or hand carry them to the laboratory.
3. Analysis
The analysis of asbestos samples can be divided into two major
parts: sample preparation and microscopy. Because of the different
asbestos uses that may be encountered by the analyst, each sample may
need different preparation steps. The choices are outlined below. There
are several different tests that are performed to identify the asbestos
species and determine the percentage. They will be explained below.
3.1. Safety
(a) Do not create unnecessary dust. Handle the samples in HEPA-
filter equipped hoods. If samples are received in bags, envelopes or
other inappropriate container, open them only in a hood having a face
velocity at or greater than 100 fpm. Transfer a small amount to a
scintillation vial and only handle the smaller amount.
(b) Open samples in a hood, never in the open lab area.
(c) Index of refraction oils can be toxic. Take care not to get this
material on the skin. Wash immediately with soap and water if this
happens.
(d) Samples that have been heated in the muffle furnace or the
drying oven may be hot. Handle them with tongs until they are cool
enough to handle.
(e) Some of the solvents used, such as THF (tetrahydrofuran), are
toxic and should only be handled in an appropriate fume hood and
according to instructions given in the Safety data sheet (SDS).
3.2. Equipment
(a) Phase contrast microscope with 10x, 16x and 40x objectives, 10x
wide-field eyepieces, G-22 Walton-Beckett graticule, Whipple disk,
polarizer, analyzer and first order red or gypsum plate, 100 Watt
illuminator, rotating position condenser with oversize phase rings,
central stop dispersion objective, Kohler illumination and a rotating
mechanical stage.
(b) Stereo microscope with reflected light illumination, transmitted
light illumination, polarizer, analyzer and first order red or gypsum
plate, and rotating stage.
(c) Negative pressure hood for the stereo microscope
(d) Muffle furnace capable of 600 [deg]C
(e) Drying oven capable of 50-150 [deg]C
(f) Aluminum specimen pans
(g) Tongs for handling samples in the furnace
(h) High dispersion index of refraction oils (Special for dispersion
staining.)
n = 1.550
n = 1.585
n = 1.590
n = 1.605
n = 1.620
n = 1.670
n = 1.680
n = 1.690
(i) A set of index of refraction oils from about n=1.350 to n=2.000
in n=0.005 increments. (Standard for Becke line analysis.)
(j) Glass slides with painted or frosted ends 1x3 inches 1mm thick,
precleaned.
(k) Cover Slips 22x22 mm, 1\1/2\
(l) Paper clips or dissection needles
(m) Hand grinder
(n) Scalpel with both 10 and 11 blades
(o) 0.1 molar HCl
(p) Decalcifying solution (Baxter Scientific Products)
Ethylenediaminetetraacetic Acid,
Tetrasodium......................................................0.7 g/l
Sodium Potassium Tartrate...................................8.0 mg/liter
Hydrochloric Acid...........................................99.2 g/liter
Sodium Tartrate.............................................0.14 g/liter
(q) Tetrahydrofuran (THF)
(r) Hotplate capable of 60 [deg]C
(s) Balance
(t) Hacksaw blade
(u) Ruby mortar and pestle
3.3. Sample Pre-Preparation
Sample preparation begins with pre-preparation which may include
chemical reduction of the matrix, heating the sample to dryness or
heating in the muffle furnace. The end result is a sample which has been
reduced to a powder that is sufficiently fine to fit under the cover
slip. Analyze different phases of samples separately, e.g., tile and the
tile mastic should be analyzed separately as the mastic may contain
asbestos while the tile may not.
(a) Wet samples
Samples with a high water content will not give the proper
dispersion colors and must be dried prior to sample mounting. Remove the
lid of the scintillation vial, place the bottle in the drying oven and
heat at 100 [deg]C to dryness (usually about 2 h). Samples which are not
submitted to the lab in glass must be removed and placed in glass vials
or aluminum weighing pans before placing them in the drying oven.
(b) Samples With Organic Interference--Muffle Furnace
These may include samples with tar as a matrix, vinyl asbestos tile,
or any other organic that can be reduced by heating. Remove the sample
from the vial and weigh in a balance to determine the weight of the
submitted portion. Place the sample in a muffle
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furnace at 500 [deg]C for 1 to 2 h or until all obvious organic material
has been removed. Retrieve, cool and weigh again to determine the weight
loss on ignition. This is necessary to determine the asbestos content of
the submitted sample, because the analyst will be looking at a reduced
sample.
Note: Heating above 600 [deg]C will cause the sample to undergo a
structural change which, given sufficient time, will convert the
chrysotile to forsterite. Heating even at lower temperatures for 1 to 2
h may have a measurable effect on the optical properties of the
minerals. If the analyst is unsure of what to expect, a sample of
standard asbestos should be heated to the same temperature for the same
length of time so that it can be examined for the proper interpretation.
(c) Samples With Organic Interference--THF
Vinyl asbestos tile is the most common material treated with this
solvent, although, substances containing tar will sometimes yield to
this treatment. Select a portion of the material and then grind it up if
possible. Weigh the sample and place it in a test tube. Add sufficient
THF to dissolve the organic matrix. This is usually about 4 to 5 mL.
Remember, THF is highly flammable. Filter the remaining material through
a tared silver membrane, dry and weigh to determine how much is left
after the solvent extraction. Further process the sample to remove
carbonate or mount directly.
(d) Samples With Carbonate Interference
Carbonate material is often found on fibers and sometimes must be
removed in order to perform dispersion microscopy. Weigh out a portion
of the material and place it in a test tube. Add a sufficient amount of
0.1 M HCl or decalcifying solution in the tube to react all the
carbonate as evidenced by gas formation; i.e., when the gas bubbles
stop, add a little more solution. If no more gas forms, the reaction is
complete. Filter the material out through a tared silver membrane, dry
and weigh to determine the weight lost.
3.4. Sample Preparation
Samples must be prepared so that accurate determination can be made
of the asbestos type and amount present. The following steps are carried
out in the low-flow hood (a low-flow hood has less than 50 fpm flow):
(1) If the sample has large lumps, is hard, or cannot be made to lie
under a cover slip, the grain size must be reduced. Place a small amount
between two slides and grind the material between them or grind a small
amount in a clean mortar and pestle. The choice of whether to use an
alumina, ruby, or diamond mortar depends on the hardness of the
material. Impact damage can alter the asbestos mineral if too much
mechanical shock occurs. (Freezer mills can completely destroy the
observable crystallinity of asbestos and should not be used). For some
samples, a portion of material can be shaved off with a scalpel, ground
off with a hand grinder or hack saw blade.
The preparation tools should either be disposable or cleaned
thoroughly. Use vigorous scrubbing to loosen the fibers during the
washing. Rinse the implements with copious amounts of water and air-dry
in a dust-free environment.
(2) If the sample is powder or has been reduced as in (1) above, it
is ready to mount. Place a glass slide on a piece of optical tissue and
write the identification on the painted or frosted end. Place two drops
of index of refraction medium n=1.550 on the slide. (The medium n=1.550
is chosen because it is the matching index for chrysotile. Dip the end
of a clean paper-clip or dissecting needle into the droplet of
refraction medium on the slide to moisten it. Then dip the probe into
the powder sample. Transfer what sticks on the probe to the slide. The
material on the end of the probe should have a diameter of about 3 mm
for a good mount. If the material is very fine, less sample may be
appropriate. For non-powder samples such as fiber mats, forceps should
be used to transfer a small amount of material to the slide. Stir the
material in the medium on the slide, spreading it out and making the
preparation as uniform as possible. Place a cover-slip on the
preparation by gently lowering onto the slide and allowing it to fall
``trapdoor'' fashion on the preparation to push out any bubbles. Press
gently on the cover slip to even out the distribution of particulate on
the slide. If there is insufficient mounting oil on the slide, one or
two drops may be placed near the edge of the coverslip on the slide.
Capillary action will draw the necessary amount of liquid into the
preparation. Remove excess oil with the point of a laboratory wiper.
Treat at least two different areas of each phase in this fashion.
Choose representative areas of the sample. It may be useful to select
particular areas or fibers for analysis. This is useful to identify
asbestos in severely inhomogeneous samples.
When it is determined that amphiboles may be present, repeat the
above process using the appropriate high-dispersion oils until an
identification is made or all six asbestos minerals have been ruled out.
Note that percent determination must be done in the index medium 1.550
because amphiboles tend to disappear in their matching mediums.
3.5. Analytical Procedure
Note: This method presumes some knowledge of mineralogy and optical
petrography.
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The analysis consists of three parts: The determination of whether
there is asbestos present, what type is present and the determination of
how much is present. The general flow of the analysis is:
(1) Gross examination.
(2) Examination under polarized light on the stereo microscope.
(3) Examination by phase-polar illumination on the compound phase
microscope.
(4) Determination of species by dispersion stain. Examination by
Becke line analysis may also be used; however, this is usually more
cumbersome for asbestos determination.
(5) Difficult samples may need to be analyzed by SEM or TEM, or the
results from those techniques combined with light microscopy for a
definitive identification. Identification of a particle as asbestos
requires that it be asbestiform. Description of particles should follow
the suggestion of Campbell. (Figure 1)
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[GRAPHIC] [TIFF OMITTED] TR10AU94.007
For the purpose of regulation, the mineral must be one of the six
minerals covered and must be in the asbestos growth habit. Large
specimen samples of asbestos generally have the gross appearance of
wood. Fibers are easily parted from it. Asbestos fibers are very long
compared with their widths. The fibers have a very high tensile strength
as demonstrated by bending without breaking. Asbestos fibers exist in
bundles that are easily parted, show longitudinal fine structure and may
be tufted at the ends showing ``bundle of sticks'' morphology. In the
microscope
[[Page 66]]
some of these properties may not be observable. Amphiboles do not always
show striations along their length even when they are asbestos. Neither
will they always show tufting. They generally do not show a curved
nature except for very long fibers. Asbestos and asbestiform minerals
are usually characterized in groups by extremely high aspect ratios
(greater than 100:1). While aspect ratio analysis is useful for
characterizing populations of fibers, it cannot be used to identify
individual fibers of intermediate to short aspect ratio. Observation of
many fibers is often necessary to determine whether a sample consists of
``cleavage fragments'' or of asbestos fibers.
Most cleavage fragments of the asbestos minerals are easily
distinguishable from true asbestos fibers. This is because true cleavage
fragments usually have larger diameters than 1 [micro]m. Internal
structure of particles larger than this usually shows them to have no
internal fibrillar structure. In addition, cleavage fragments of the
monoclinic amphiboles show inclined extinction under crossed polars with
no compensator. Asbestos fibers usually show extinction at zero degrees
or ambiguous extinction if any at all. Morphologically, the larger
cleavage fragments are obvious by their blunt or stepped ends showing
prismatic habit. Also, they tend to be acicular rather than filiform.
Where the particles are less than 1 [micro]m in diameter and have an
aspect ratio greater than or equal to 3:1, it is recommended that the
sample be analyzed by SEM or TEM if there is any question whether the
fibers are cleavage fragments or asbestiform particles.
Care must be taken when analyzing by electron microscopy because the
interferences are different from those in light microscopy and may
structurally be very similar to asbestos. The classic interference is
between anthophyllite and biopyribole or intermediate fiber. Use the
same morphological clues for electron microscopy as are used for light
microscopy, e.g. fibril splitting, internal longitudinal striation,
fraying, curvature, etc.
(1) Gross examination:
Examine the sample, preferably in the glass vial. Determine the
presence of any obvious fibrous component. Estimate a percentage based
on previous experience and current observation. Determine whether any
pre- preparation is necessary. Determine the number of phases present.
This step may be carried out or augmented by observation at 6 to 40x
under a stereo microscope.
(2) After performing any necessary pre-preparation, prepare slides
of each phase as described above. Two preparations of the same phase in
the same index medium can be made side-by-side on the same glass for
convenience. Examine with the polarizing stereo microscope. Estimate the
percentage of asbestos based on the amount of birefringent fiber
present.
(3) Examine the slides on the phase-polar microscopes at
magnifications of 160 and 400x. Note the morphology of the fibers. Long,
thin, very straight fibers with little curvature are indicative of
fibers from the amphibole family. Curved, wavy fibers are usually
indicative of chrysotile. Estimate the percentage of asbestos on the
phase-polar microscope under conditions of crossed polars and a gypsum
plate. Fibers smaller than 1.0 [micro]m in thickness must be identified
by inference to the presence of larger, identifiable fibers and
morphology. If no larger fibers are visible, electron microscopy should
be performed. At this point, only a tentative identification can be
made. Full identification must be made with dispersion microscopy.
Details of the tests are included in the appendices.
(4) Once fibers have been determined to be present, they must be
identified. Adjust the microscope for dispersion mode and observe the
fibers. The microscope has a rotating stage, one polarizing element, and
a system for generating dark-field dispersion microscopy (see Section
4.6. of this appendix). Align a fiber with its length parallel to the
polarizer and note the color of the Becke lines. Rotate the stage to
bring the fiber length perpendicular to the polarizer and note the
color. Repeat this process for every fiber or fiber bundle examined. The
colors must be consistent with the colors generated by standard asbestos
reference materials for a positive identification. In n=1.550,
amphiboles will generally show a yellow to straw-yellow color indicating
that the fiber indices of refraction are higher than the liquid. If
long, thin fibers are noted and the colors are yellow, prepare further
slides as above in the suggested matching liquids listed below:
------------------------------------------------------------------------
Type of asbestos Index of refraction
------------------------------------------------------------------------
Chrysotile.......................... n=1.550.
Amosite............................. n=1.670 or 1.680.
Crocidolite......................... n=1.690.
Anthophyllite....................... n=1.605 and 1.620.
Tremolite........................... n=1.605 and 1.620.
Actinolite.......................... n=1.620.
------------------------------------------------------------------------
Where more than one liquid is suggested, the first is preferred;
however, in some cases this liquid will not give good dispersion color.
Take care to avoid interferences in the other liquid; e.g., wollastonite
in n=1.620 will give the same colors as tremolite. In n=1.605
wollastonite will appear yellow in all directions. Wollastonite may be
determined under crossed polars as it will change from blue to yellow as
it is rotated along its fiber axis by tapping on the cover slip.
Asbestos minerals will not change in this way.
Determination of the angle of extinction may, when present, aid in
the determination
[[Page 67]]
of anthophyllite from tremolite. True asbestos fibers usually have
0[deg] extinction or ambiguous extinction, while cleavage fragments have
more definite extinction.
Continue analysis until both preparations have been examined and all
present species of asbestos are identified. If there are no fibers
present, or there is less than 0.1% present, end the analysis with the
minimum number of slides (2).
(5) Some fibers have a coating on them which makes dispersion
microscopy very difficult or impossible. Becke line analysis or electron
microscopy may be performed in those cases. Determine the percentage by
light microscopy. TEM analysis tends to overestimate the actual
percentage present.
(6) Percentage determination is an estimate of occluded area,
tempered by gross observation. Gross observation information is used to
make sure that the high magnification microscopy does not greatly over-
or under- estimate the amount of fiber present. This part of the
analysis requires a great deal of experience. Satisfactory models for
asbestos content analysis have not yet been developed, although some
models based on metallurgical grain-size determination have found some
utility. Estimation is more easily handled in situations where the grain
sizes visible at about 160x are about the same and the sample is
relatively homogeneous.
View all of the area under the cover slip to make the percentage
determination. View the fields while moving the stage, paying attention
to the clumps of material. These are not usually the best areas to
perform dispersion microscopy because of the interference from other
materials. But, they are the areas most likely to represent the accurate
percentage in the sample. Small amounts of asbestos require slower
scanning and more frequent analysis of individual fields.
Report the area occluded by asbestos as the concentration. This
estimate does not generally take into consideration the difference in
density of the different species present in the sample. For most samples
this is adequate. Simulation studies with similar materials must be
carried out to apply microvisual estimation for that purpose and is
beyond the scope of this procedure.
(7) Where successive concentrations have been made by chemical or
physical means, the amount reported is the percentage of the material in
the ``as submitted'' or original state. The percentage determined by
microscopy is multiplied by the fractions remaining after pre-
preparation steps to give the percentage in the original sample. For
example:
Step 1. 60% remains after heating at 550 [deg]C for 1 h.
Step 2. 30% of the residue of step 1 remains after dissolution of
carbonate in 0.1 m HCl.
Step 3. Microvisual estimation determines that 5% of the sample is
chrysotile asbestos.
The reported result is:
R=(Microvisual result in percent)x(Fraction remaining after step
2)x(Fraction remaining of original sample after step 1)
R=(5)x(.30)x(.60)=0.9%
(8) Report the percent and type of asbestos present. For samples
where asbestos was identified, but is less than 1.0%, report ``Asbestos
present, less than 1.0%.'' There must have been at least two observed
fibers or fiber bundles in the two preparations to be reported as
present. For samples where asbestos was not seen, report as ``None
Detected.''
4. Auxiliary Information
Because of the subjective nature of asbestos analysis, certain
concepts and procedures need to be discussed in more depth. This
information will help the analyst understand why some of the procedures
are carried out the way they are.
4.1. Light
Light is electromagnetic energy. It travels from its source in
packets called quanta. It is instructive to consider light as a plane
wave. The light has a direction of travel. Perpendicular to this and
mutually perpendicular to each other, are two vector components. One is
the magnetic vector and the other is the electric vector. We shall only
be concerned with the electric vector. In this description, the
interaction of the vector and the mineral will describe all the
observable phenomena. From a light source such a microscope illuminator,
light travels in all different direction from the filament.
In any given direction away from the filament, the electric vector
is perpendicular to the direction of travel of a light ray. While
perpendicular, its orientation is random about the travel axis. If the
electric vectors from all the light rays were lined up by passing the
light through a filter that would only let light rays with electric
vectors oriented in one direction pass, the light would then be
POLARIZED.
Polarized light interacts with matter in the direction of the
electric vector. This is the polarization direction. Using this property
it is possible to use polarized light to probe different materials and
identify them by how they interact with light.
The speed of light in a vacuum is a constant at about 2.99x10\8\ m/
s. When light travels in different materials such as air, water,
minerals or oil, it does not travel at this speed. It travels slower.
This slowing is a function of both the material through which the light
is traveling and the wavelength or frequency of the light. In general,
the more
[[Page 68]]
dense the material, the slower the light travels. Also, generally, the
higher the frequency, the slower the light will travel. The ratio of the
speed of light in a vacuum to that in a material is called the index of
refraction (n). It is usually measured at 589 nm (the sodium D line). If
white light (light containing all the visible wavelengths) travels
through a material, rays of longer wavelengths will travel faster than
those of shorter wavelengths, this separation is called dispersion.
Dispersion is used as an identifier of materials as described in Section
4.6.
4.2. Material Properties
Materials are either amorphous or crystalline. The difference
between these two descriptions depends on the positions of the atoms in
them. The atoms in amorphous materials are randomly arranged with no
long range order. An example of an amorphous material is glass. The
atoms in crystalline materials, on the other hand, are in regular arrays
and have long range order. Most of the atoms can be found in highly
predictable locations. Examples of crystalline material are salt, gold,
and the asbestos minerals.
It is beyond the scope of this method to describe the different
types of crystalline materials that can be found, or the full
description of the classes into which they can fall. However, some
general crystallography is provided below to give a foundation to the
procedures described.
With the exception of anthophyllite, all the asbestos minerals
belong to the monoclinic crystal type. The unit cell is the basic
repeating unit of the crystal and for monoclinic crystals can be
described as having three unequal sides, two 90[deg] angles and one
angle not equal to 90[deg]. The orthorhombic group, of which
anthophyllite is a member has three unequal sides and three 90[deg]
angles. The unequal sides are a consequence of the complexity of fitting
the different atoms into the unit cell. Although the atoms are in a
regular array, that array is not symmetrical in all directions. There is
long range order in the three major directions of the crystal. However,
the order is different in each of the three directions. This has the
effect that the index of refraction is different in each of the three
directions. Using polarized light, we can investigate the index of
refraction in each of the directions and identify the mineral or
material under investigation. The indices [alpha], [beta], and [gamma]
are used to identify the lowest, middle, and highest index of refraction
respectively. The x direction, associated with [alpha] is called the
fast axis. Conversely, the z direction is associated with [gamma] and is
the slow direction. Crocidolite has [alpha] along the fiber length
making it ``length-fast''. The remainder of the asbestos minerals have
the [gamma] axis along the fiber length. They are called ``length-
slow''. This orientation to fiber length is used to aid in the
identification of asbestos.
4.3. Polarized Light Technique
Polarized light microscopy as described in this section uses the
phase-polar microscope described in Section 3.2. A phase contrast
microscope is fitted with two polarizing elements, one below and one
above the sample. The polarizers have their polarization directions at
right angles to each other. Depending on the tests performed, there may
be a compensator between these two polarizing elements. Light emerging
from a polarizing element has its electric vector pointing in the
polarization direction of the element. The light will not be
subsequently transmitted through a second element set at a right angle
to the first element. Unless the light is altered as it passes from one
element to the other, there is no transmission of light.
4.4. Angle of Extinction
Crystals which have different crystal regularity in two or three
main directions are said to be anisotropic. They have a different index
of refraction in each of the main directions. When such a crystal is
inserted between the crossed polars, the field of view is no longer dark
but shows the crystal in color. The color depends on the properties of
the crystal. The light acts as if it travels through the crystal along
the optical axes. If a crystal optical axis were lined up along one of
the polarizing directions (either the polarizer or the analyzer) the
light would appear to travel only in that direction, and it would blink
out or go dark. The difference in degrees between the fiber direction
and the angle at which it blinks out is called the angle of extinction.
When this angle can be measured, it is useful in identifying the
mineral. The procedure for measuring the angle of extinction is to first
identify the polarization direction in the microscope. A commercial
alignment slide can be used to establish the polarization directions or
use anthophyllite or another suitable mineral. This mineral has a zero
degree angle of extinction and will go dark to extinction as it aligns
with the polarization directions. When a fiber of anthophyllite has gone
to extinction, align the eyepiece reticle or graticule with the fiber so
that there is a visual cue as to the direction of polarization in the
field of view. Tape or otherwise secure the eyepiece in this position so
it will not shift.
After the polarization direction has been identified in the field of
view, move the particle of interest to the center of the field of view
and align it with the polarization direction. For fibers, align the
fiber along this direction. Note the angular reading of the rotating
stage. Looking at the particle, rotate the stage until the fiber goes
dark or ``blinks
[[Page 69]]
out''. Again note the reading of the stage. The difference in the first
reading and the second is an angle of extinction.
The angle measured may vary as the orientation of the fiber changes
about its long axis. Tables of mineralogical data usually report the
maximum angle of extinction. Asbestos forming minerals, when they
exhibit an angle of extinction, usually do show an angle of extinction
close to the reported maximum, or as appropriate depending on the
substitution chemistry.
4.5. Crossed Polars with Compensator
When the optical axes of a crystal are not lined up along one of the
polarizing directions (either the polarizer or the analyzer) part of the
light travels along one axis and part travels along the other visible
axis. This is characteristic of birefringent materials.
The color depends on the difference of the two visible indices of
refraction and the thickness of the crystal. The maximum difference
available is the difference between the [alpha] and the [gamma] axes.
This maximum difference is usually tabulated as the birefringence of the
crystal.
For this test, align the fiber at 45[deg] to the polarization
directions in order to maximize the contribution to each of the optical
axes. The colors seen are called retardation colors. They arise from the
recombination of light which has traveled through the two separate
directions of the crystal. One of the rays is retarded behind the other
since the light in that direction travels slower. On recombination, some
of the colors which make up white light are enhanced by constructive
interference and some are suppressed by destructive interference. The
result is a color dependent on the difference between the indices and
the thickness of the crystal. The proper colors, thicknesses, and
retardations are shown on a Michel-Levy chart. The three items,
retardation, thickness and birefringence are related by the following
relationship:
R=t(n[gamma]--n[alpha])
R=retardation, t=crystal thickness in [micro]m, and
n[alpha],[gamma]=indices of refraction.
Examination of the equation for asbestos minerals reveals that the
visible colors for almost all common asbestos minerals and fiber sizes
are shades of gray and black. The eye is relatively poor at
discriminating different shades of gray. It is very good at
discriminating different colors. In order to compensate for the low
retardation, a compensator is added to the light train between the
polarization elements. The compensator used for this test is a gypsum
plate of known thickness and birefringence. Such a compensator when
oriented at 45[deg] to the polarizer direction, provides a retardation
of 530 nm of the 530 nm wavelength color. This enhances the red color
and gives the background a characteristic red to red-magenta color. If
this ``full-wave'' compensator is in place when the asbestos preparation
is inserted into the light train, the colors seen on the fibers are
quite different. Gypsum, like asbestos has a fast axis and a slow axis.
When a fiber is aligned with its fast axis in the same direction as the
fast axis of the gypsum plate, the ray vibrating in the slow direction
is retarded by both the asbestos and the gypsum. This results in a
higher retardation than would be present for either of the two minerals.
The color seen is a second order blue. When the fiber is rotated 90[deg]
using the rotating stage, the slow direction of the fiber is now aligned
with the fast direction of the gypsum and the fast direction of the
fiber is aligned with the slow direction of the gypsum. Thus, one ray
vibrates faster in the fast direction of the gypsum, and slower in the
slow direction of the fiber; the other ray will vibrate slower in the
slow direction of the gypsum and faster in the fast direction of the
fiber. In this case, the effect is subtractive and the color seen is a
first order yellow. As long as the fiber thickness does not add
appreciably to the color, the same basic colors will be seen for all
asbestos types except crocidolite. In crocidolite the colors will be
weaker, may be in the opposite directions, and will be altered by the
blue absorption color natural to crocidolite. Hundreds of other
materials will give the same colors as asbestos, and therefore, this
test is not definitive for asbestos. The test is useful in
discriminating against fiberglass or other amorphous fibers such as some
synthetic fibers. Certain synthetic fibers will show retardation colors
different than asbestos; however, there are some forms of polyethylene
and aramid which will show morphology and retardation colors similar to
asbestos minerals. This test must be supplemented with a positive
identification test when birefringent fibers are present which can not
be excluded by morphology. This test is relatively ineffective for use
on fibers less than 1 [micro]m in diameter. For positive confirmation
TEM or SEM should be used if no larger bundles or fibers are visible.
4.6. Dispersion Staining
Dispersion microscopy or dispersion staining is the method of choice
for the identification of asbestos in bulk materials. Becke line
analysis is used by some laboratories and yields the same results as
does dispersion staining for asbestos and can be used in lieu of
dispersion staining. Dispersion staining is performed on the same
platform as the phase-polar analysis with the analyzer and compensator
removed. One polarizing element remains to define the direction of the
[[Page 70]]
light so that the different indices of refraction of the fibers may be
separately determined. Dispersion microscopy is a dark-field technique
when used for asbestos. Particles are imaged with scattered light. Light
which is unscattered is blocked from reaching the eye either by the back
field image mask in a McCrone objective or a back field image mask in
the phase condenser. The most convenient method is to use the rotating
phase condenser to move an oversized phase ring into place. The ideal
size for this ring is for the central disk to be just larger than the
objective entry aperture as viewed in the back focal plane. The larger
the disk, the less scattered light reaches the eye. This will have the
effect of diminishing the intensity of dispersion color and will shift
the actual color seen. The colors seen vary even on microscopes from the
same manufacturer. This is due to the different bands of wavelength
exclusion by different mask sizes. The mask may either reside in the
condenser or in the objective back focal plane. It is imperative that
the analyst determine by experimentation with asbestos standards what
the appropriate colors should be for each asbestos type. The colors
depend also on the temperature of the preparation and the exact
chemistry of the asbestos. Therefore, some slight differences from the
standards should be allowed. This is not a serious problem for
commercial asbestos uses. This technique is used for identification of
the indices of refraction for fibers by recognition of color. There is
no direct numerical readout of the index of refraction. Correlation of
color to actual index of refraction is possible by referral to published
conversion tables. This is not necessary for the analysis of asbestos.
Recognition of appropriate colors along with the proper morphology are
deemed sufficient to identify the commercial asbestos minerals. Other
techniques including SEM, TEM, and XRD may be required to provide
additional information in order to identify other types of asbestos.
Make a preparation in the suspected matching high dispersion oil,
e.g., n=1.550 for chrysotile. Perform the preliminary tests to determine
whether the fibers are birefringent or not. Take note of the
morphological character. Wavy fibers are indicative of chrysotile while
long, straight, thin, frayed fibers are indicative of amphibole
asbestos. This can aid in the selection of the appropriate matching oil.
The microscope is set up and the polarization direction is noted as in
Section 4.4. Align a fiber with the polarization direction. Note the
color. This is the color parallel to the polarizer. Then rotate the
fiber rotating the stage 90[deg] so that the polarization direction is
across the fiber. This is the perpendicular position. Again note the
color. Both colors must be consistent with standard asbestos minerals in
the correct direction for a positive identification of asbestos. If only
one of the colors is correct while the other is not, the identification
is not positive. If the colors in both directions are bluish-white, the
analyst has chosen a matching index oil which is higher than the correct
matching oil, e.g. the analyst has used n=1.620 where chrysotile is
present. The next lower oil (Section 3.5.) should be used to prepare
another specimen. If the color in both directions is yellow-white to
straw-yellow-white, this indicates that the index of the oil is lower
than the index of the fiber, e.g. the preparation is in n=1.550 while
anthophyllite is present. Select the next higher oil (Section 3.5.) and
prepare another slide. Continue in this fashion until a positive
identification of all asbestos species present has been made or all
possible asbestos species have been ruled out by negative results in
this test. Certain plant fibers can have similar dispersion colors as
asbestos. Take care to note and evaluate the morphology of the fibers or
remove the plant fibers in pre- preparation. Coating material on the
fibers such as carbonate or vinyl may destroy the dispersion color.
Usually, there will be some outcropping of fiber which will show the
colors sufficient for identification. When this is not the case, treat
the sample as described in Section 3.3. and then perform dispersion
staining. Some samples will yield to Becke line analysis if they are
coated or electron microscopy can be used for identification.
5. References
5.1. Crane, D.T., Asbestos in Air, OSHA method ID160, Revised
November 1992.
5.2. Ford, W.E., Dana's Textbook of Mineralogy; Fourth Ed.; John
Wiley and Son, New York, 1950, p. vii.
5.3. Selikoff,.I.J., Lee, D.H.K., Asbestos and Disease, Academic
Press, New York, 1978, pp. 3,20.
5.4. Women Inspectors of Factories. Annual Report for 1898, H.M.
Statistical Office, London, p. 170 (1898).
5.5. Selikoff, I.J., Lee, D.H.K., Asbestos and Disease, Academic
Press, New York, 1978, pp. 26,30.
5.6. Campbell, W.J., et al, Selected Silicate Minerals and Their
Asbestiform Varieties, United States Department of the Interior, Bureau
of Mines, Information Circular 8751, 1977.
5.7. Asbestos, Code of Federal Regulations, 29 CFR 1910.1001 and 29
CFR 1926.58.
5.8. National Emission Standards for Hazardous Air Pollutants;
Asbestos NESHAP Revision, Federal Register, Vol. 55, No. 224, 20
November 1990, p. 48410.
5.9. Ross, M. The Asbestos Minerals: Definitions, Description, Modes
of Formation, Physical and Chemical Properties and Health Risk to the
Mining Community, Nation Bureau of Standards Special Publication,
Washington, DC, 1977.
[[Page 71]]
5.10. Lilis, R., Fibrous Zeolites and Endemic Mesothelioma in
Cappadocia, Turkey, J. Occ Medicine, 1981, 23,(8),548-550.
5.11. Occupational Exposure to Asbestos--1972, U.S. Department of
Health, Education and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health, HSM-72-
10267.
5.12. Campbell, W.J., et al, Relationship of Mineral Habit to Size
Characteristics for Tremolite Fragments and Fibers, United States
Department of the Interior, Bureau of Mines, Information Circular 8367,
1979.
5.13. Mefford, D., DCM Laboratory, Denver, private communication,
July 1987.
5.14. Deer, W.A., Howie, R.A., Zussman, J., Rock Forming Minerals,
Longman, Thetford, UK, 1974.
5.15. Kerr, P.F., Optical Mineralogy; Third Ed. McGraw-Hill, New
York, 1959.
5.16. Veblen, D.R. (Ed.), Amphiboles and Other Hydrous Pyriboles--
Mineralogy, Reviews in Mineralogy, Vol 9A, Michigan, 1982, pp 1-102.
5.17. Dixon, W.C., Applications of Optical Microscopy in the
Analysis of Asbestos and Quartz, ACS Symposium Series, No. 120,
Analytical Techniques in Occupational Health Chemistry, 1979.
5.18. Polarized Light Microscopy, McCrone Research Institute,
Chicago, 1976.
5.19. Asbestos Identification, McCrone Research Institute, G & G
printers, Chicago, 1987.
5.20. McCrone, W.C., Calculation of Refractive Indices from
Dispersion Staining Data, The Microscope, No 37, Chicago, 1989.
5.21. Levadie, B. (Ed.), Asbestos and Other Health Related
Silicates, ASTM Technical Publication 834, ASTM, Philadelphia 1982.
5.22. Steel, E. and Wylie, A., Riordan, P.H. (Ed.), Mineralogical
Characteristics of Asbestos, Geology of Asbestos Deposits, pp. 93-101,
SME-AIME, 1981.
5.23. Zussman, J., The Mineralogy of Asbestos, Asbestos: Properties,
Applications and Hazards, pp. 45-67 Wiley, 1979.
[51 FR 22733, June 20, 1986]
Editorial Note: For Federal Register citations affectingSec.
1910.1001, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 1910.1002 Coal tar pitch volatiles; interpretation of term.
As used inSec. 1910.1000 (Table Z-1), coal tar pitch volatiles
include the fused polycyclic hydrocarbons which volatilize from the
distillation residues of coal, petroleum (excluding asphalt), wood, and
other organic matter. Asphalt (CAS 8052-42-4, and CAS 64742-93-4) is not
covered under the ``coal tar pitch volatiles'' standard.
[48 FR 2768, Jan. 21, 1983]
Sec. 1910.1003 13 Carcinogens (4-Nitrobiphenyl, etc.).
(a) Scope and application. (1) This section applies to any area in
which the 13 carcinogens addressed by this section are manufactured,
processed, repackaged, released, handled, or stored, but shall not apply
to transshipment in sealed containers, except for the labeling
requirements under paragraphs (e)(2), (3) and (4) of this section. The
13 carcinogens are the following:
4-Nitrobiphenyl, Chemical Abstracts Service Register Number (CAS No.)
92933;
alpha-Naphthylamine, CAS No. 134327;
methyl chloromethyl ether, CAS No. 107302;
3,'-Dichlorobenzidine (and its salts) CAS No. 91941;
bis-Chloromethyl ether, CAS No. 542881;
beta-Naphthylamine, CAS No. 91598;
Benzidine, CAS No. 92875;
4-Aminodiphenyl, CAS No. 92671;
Ethyleneimine, CAS No. 151564;
beta-Propiolactone, CAS No. 57578;
2-Acetylaminofluorene, CAS No. 53963;
4-Dimethylaminoazo-benezene, CAS No. 60117; and
N-Nitrosodimethylamine, CAS No. 62759.
(2) This section shall not apply to the following:
(i) Solid or liquid mixtures containing less than 0.1 percent by
weight or volume of 4-Nitrobiphenyl; methyl chloromethyl ether; bis-
chloromethyl ether; beta-Naphthylamine; benzidine or 4-Aminodiphenyl;
and
(ii) Solid or liquid mixtures containing less than 1.0 percent by
weight or volume of alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); Ethyleneimine; beta-Propiolactone; 2-Acetylaminofluorene; 4-
Dimethylaminoazobenzene, or N-Nitrosodimethylamine.
(b) Definitions. For the purposes of this section:
Absolute filter is one capable of retaining 99.97 percent of a mono
disperse aerosol of 0.3 [micro]m particles.
Authorized employee means an employee whose duties require him to be
in the regulated area and who has been specifically assigned by the
employer.
Clean change room means a room where employees put on clean clothing
[[Page 72]]
and/or protective equipment in an environment free of the 13 carcinogens
addressed by this section. The clean change room shall be contiguous to
and have an entry from a shower room, when the shower room facilities
are otherwise required in this section.
Closed system means an operation involving a carcinogen addressed by
this section where containment prevents the release of the material into
regulated areas, non-regulated areas, or the external environment.
Decontamination means the inactivation of a carcinogen addressed by
this section or its safe disposal.
Director means the Director, National Institute for Occupational
Safety and Health, or any person directed by him or the Secretary of
Health and Human Services to act for the Director.
Disposal means the safe removal of the carcinogens addressed by this
section from the work environment.
Emergency means an unforeseen circumstance or set of circumstances
resulting in the release of a carcinogen addressed by this section that
may result in exposure to or contact with the material.
External environment means any environment external to regulated and
nonregulated areas.
Isolated system means a fully enclosed structure other than the
vessel of containment of a carcinogen addressed by this section that is
impervious to the passage of the material and would prevent the entry of
the carcinogen addressed by this section into regulated areas,
nonregulated areas, or the external environment, should leakage or
spillage from the vessel of containment occur.
Laboratory-type hood is a device enclosed on the three sides and the
top and bottom, designed and maintained so as to draw air inward at an
average linear face velocity of 150 feet per minute with a minimum of
125 feet per minute; designed, constructed, and maintained in such a way
that an operation involving a carcinogen addressed by this section
within the hood does not require the insertion of any portion of any
employee's body other than his hands and arms.
Nonregulated area means any area under the control of the employer
where entry and exit is neither restricted nor controlled.
Open-vessel system means an operation involving a carcinogen
addressed by this section in an open vessel that is not in an isolated
system, a laboratory-type hood, nor in any other system affording
equivalent protection against the entry of the material into regulated
areas, non-regulated areas, or the external environment.
Protective clothing means clothing designed to protect an employee
against contact with or exposure to a carcinogen addressed by this
section.
Regulated area means an area where entry and exit is restricted and
controlled.
(c) Requirements for areas containing a carcinogen addressed by this
section. A regulated area shall be established by an employer where a
carcinogen addressed by this section is manufactured, processed, used,
repackaged, released, handled or stored. All such areas shall be
controlled in accordance with the requirements for the following
category or categories describing the operation involved:
(1) Isolated systems. Employees working with a carcinogen addressed
by this section within an isolated system such as a ``glove box'' shall
wash their hands and arms upon completion of the assigned task and
before engaging in other activities not associated with the isolated
system.
(2) Closed system operation. (i) Within regulated areas where the
carcinogens addressed by this section are stored in sealed containers,
or contained in a closed system, including piping systems, with any
sample ports or openings closed while the carcinogens addressed by this
section are contained within, access shall be restricted to authorized
employees only.
(ii) Employees exposed to 4-Nitrobiphenyl; alpha-Naphthylamine; 3,'-
Dichlorobenzidine (and its salts); beta-Naphthylamine; benzidine; 4-
Aminodiphenyl; 2-Acetylaminofluorene; 4-Dimethylaminoazo-benzene; and N-
Nitrosodimethylamine shall be required to wash hands, forearms, face,
and neck upon each exit from the regulated areas, close to the point of
exit, and before engaging in other activities.
[[Page 73]]
(3) Open-vessel system operations. Open-vessel system operations as
defined in paragraph (b)(13) of this section are prohibited.
(4) Transfer from a closed system, charging or discharging point
operations, or otherwise opening a closed system. In operations
involving ``laboratory-type hoods,'' or in locations where the
carcinogens addressed by this section are contained in an otherwise
``closed system,'' but is transferred, charged, or discharged into other
normally closed containers, the provisions of this paragraph shall
apply.
(i) Access shall be restricted to authorized employees only.
(ii) Each operation shall be provided with continuous local exhaust
ventilation so that air movement is always from ordinary work areas to
the operation. Exhaust air shall not be discharged to regulated areas,
nonregulated areas or the external environment unless decontaminated.
Clean makeup air shall be introduced in sufficient volume to maintain
the correct operation of the local exhaust system.
(iii) Employees shall be provided with, and required to wear, clean,
full body protective clothing (smocks, coveralls, or long-sleeved shirt
and pants), shoe covers and gloves prior to entering the regulated area.
(iv) Employers must provide each employee engaged in handling
operations involving the carcinogens 4-Nitrobiphenyl, alpha-
Naphthylamine, 3,3[min]-Dichlorobenzidine (and its salts), beta-
Naphthylamine, Benzidine, 4-Aminodiphenyl, 2-Acetylaminofluorene, 4-
Dimethylaminoazo-benzene, and N-Nitrosodimethylamine, addressed by this
section, with, and ensure that each of these employees wears and uses, a
NIOSH-certified air-purifying, half-mask respirator with particulate
filters. Employers also must provide each employee engaged in handling
operations involving the carcinogens methyl chloromethyl ether, bis-
Chloromethyl ether, Ethyleneimine, and beta-Propiolactone, addressed by
this section, with, and ensure that each of these employees wears and
uses any self-contained breathing apparatus that has a full facepiece
and is operated in a pressure-demand or other positive-pressure mode, or
any supplied-air respirator that has a full facepiece and is operated in
a pressure-demand or other positive-pressure mode in combination with an
auxiliary self-contained positive-pressure breathing apparatus.
Employers may substitute a respirator affording employees higher levels
of protection than these respirators.
(v) Prior to each exit from a regulated area, employees shall be
required to remove and leave protective clothing and equipment at the
point of exit and at the last exit of the day, to place used clothing
and equipment in impervious containers at the point of exit for purposes
of decontamination or disposal. The contents of such impervious
containers shall be identified, as required under paragraph (e) of this
section.
(vi) Drinking fountains are prohibited in the regulated area.
(vii) Employees shall be required to wash hands, forearms, face, and
neck on each exit from the regulated area, close to the point of exit,
and before engaging in other activities and employees exposed to 4-
Nitrobiphenyl; alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); beta-Naphthylamine; Benzidine; 4-Aminodiphenyl; 2-
Acetylaminofluorene; 4-Dimethylaminoazo-benzene; and N-
Nitrosodimethylamine shall be required to shower after the last exit of
the day.
(5) Maintenance and decontamination activities. In cleanup of leaks
of spills, maintenance, or repair operations on contaminated systems or
equipment, or any operations involving work in an area where direct
contact with a carcinogen addressed by this section could result, each
authorized employee entering that area shall:
(i) Be provided with and required to wear clean, impervious
garments, including gloves, boots, and continuous-air supplied hood in
accordance withSec. 1910.134;
(ii) Be decontaminated before removing the protective garments and
hood;
(iii) Be required to shower upon removing the protective garments
and hood.
[[Page 74]]
(d) General regulated area requirements--(1) Respiratory program.
The employer must implement a respiratory protection program in
accordance withSec. 1910.134 (b), (c), (d) (except (d)(1)(iii) and
(iv), and (d)(3)), and (e) through (m), which covers each employee
required by this section to use a respirator.
(2) Emergencies. In an emergency, immediate measures including, but
not limited to, the requirements of paragraphs (d)(2) (i) through (v) of
this section shall be implemented.
(i) The potentially affected area shall be evacuated as soon as the
emergency has been determined.
(ii) Hazardous conditions created by the emergency shall be
eliminated and the potentially affected area shall be decontaminated
prior to the resumption of normal operations.
(iii) Special medical surveillance by a physician shall be
instituted within 24 hours for employees present in the potentially
affected area at the time of the emergency.
(iv) Where an employee has a known contact with a carcinogen
addressed by this section, such employee shall be required to shower as
soon as possible, unless contraindicated by physical injuries.
(v) Emergency deluge showers and eyewash fountains supplied with
running potable water shall be located near, within sight of, and on the
same level with locations where a direct exposure to Ethyleneimine or
beta-Propiolactone only would be most likely as a result of equipment
failure or improper work practice.
(3) Hygiene facilities and practices. (i) Storage or consumption of
food, storage or use of containers of beverages, storage or application
of cosmetics, smoking, storage of smoking materials, tobacco products or
other products for chewing, or the chewing of such products are
prohibited in regulated areas.
(ii) Where employees are required by this section to wash, washing
facilities shall be provided in accordance withSec. 1910.141(d) (1)
and (2) (ii) through (vii).
(iii) Where employees are required by this section to shower, shower
facilities shall be provided in accordance withSec. 1910.141(d)(3).
(iv) Where employees wear protective clothing and equipment, clean
change rooms shall be provided for the number of such employees required
to change clothes, in accordance withSec. 1910.141(e).
(v) Where toilets are in regulated areas, such toilets shall be in a
separate room.
(4) Contamination control. (i) Except for outdoor systems, regulated
areas shall be maintained under pressure negative with respect to
nonregulated areas. Local exhaust ventilation may be used to satisfy
this requirement. Clean makeup air in equal volume shall replace air
removed.
(ii) Any equipment, material, or other item taken into or removed
from a regulated area shall be done so in a manner that does not cause
contamination in nonregulated areas or the external environment.
(iii) Decontamination procedures shall be established and
implemented to remove carcinogens addressed by this section from the
surfaces of materials, equipment, and the decontamination facility.
(iv) Dry sweeping and dry mopping are prohibited for 4-
Nitrobiphenyl; alpha-Naphthylamine; 3,'-Dichlorobenzidine (and its
salts); beta-Naphthylamine; Benzidine; 4-Aminodiphenyl; 2-
Acetylaminofluorene; 4-Dimethylaminoazo-benzene and N-
Nitrosodimethylamine.
(e) Communication of hazards--(1) Hazard communication. (i) Chemical
manufacturers, importers, distributors and employers shall comply with
all requirements of the Hazard Communication Standard (HCS) (Sec.
1910.1200) for each carcinogen listed in paragraph (e)(1)(iv) of this
section.
(ii) In classifying the hazards of carcinogens listed in paragraph
(e)(1)(iv) of this section, at least the hazards listed in paragraph
(e)(1)(iv) are to be addressed.
(iii) Employers shall include the carcinogens listed in paragraph
(e)(1)(iv) of this section in the hazard communication program
established to comply with the HCS (Sec. 1910.1200). Employers shall
ensure that each employee has access to labels on containers of the
carcinogens listed in paragraph (e)(1)(iv) and to safety data sheets,
and
[[Page 75]]
is trained in accordance with the requirements of HCS and paragraph
(e)(4) of this section.
(iv) List of Carcinogens:
(A) 4-Nitrobiphenyl: Cancer.
(B) alpha-Naphthylamine: Cancer; skin irritation; and acute toxicity
effects.
(C) Methyl chloromethyl ether: Cancer; skin, eye and respiratory
effects; acute toxicity effects; and flammability.
(D) 3,3[min]-Dichlorobenzidine (and its salts): Cancer and skin
sensitization.
(E) bis-Chloromethyl ether: Cancer; skin, eye, and respiratory tract
effects; acute toxicity effects; and flammability.
(F) beta-Naphthylamine: Cancer and acute toxicity effects.
(G) Benzidine: Cancer and acute toxicity effects.
(H) 4-Aminodiphenyl: Cancer.
(I) Ethyleneimine: Cancer; mutagenicity; skin and eye effects; liver
effects; kidney effects; acute toxicity effects; and flammability.
(J) beta-Propiolactone: Cancer; skin irritation; eye effects; and
acute toxicity effects.
(K) 2-Acetylaminofluorene: Cancer.
(L) 4-Dimethylaminoazo-benzene: Cancer; skin effects; and
respiratory tract irritation.
(M) N-Nitrosodimethylamine: Cancer; liver effects; and acute
toxicity effects.
(2) Signs. (i) The employer shall post entrances to regulated areas
with signs bearing the legend:
DANGER
(CHEMICAL IDENTIFICATION)
MAY CAUSE CANCER
AUTHORIZED PERSONNEL ONLY
(ii) The employer shall post signs at entrances to regulated areas
containing operations covered in paragraph (c)(5) of this section. The
signs shall bear the legend:
DANGER
(CHEMICAL IDENTIFICATION)
MAY CAUSE CANCER
WEAR AIR-SUPPLIED HOODS, IMPERVIOUS SUITS, AND PROTECTIVE EQUIPMENT IN
THIS AREA
AUTHORIZED PERSONNEL ONLY
(iii) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (e)(2)(i) of this section:
CANCER-SUSPECT AGENT
AUTHORIZED PERSONNEL ONLY
(iv) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (e)(2)(ii) of this section:
CANCER-SUSPECT AGENT EXPOSED IN THIS AREA
IMPERVIOUS SUIT INCLUDING GLOVES, BOOTS, AND AIR-SUPPLIED HOOD REQUIRED
AT ALL TIMES
AUTHORIZED PERSONNEL ONLY
(v) Appropriate signs and instructions shall be posted at the
entrance to, and exit from, regulated areas, informing employees of the
procedures that must be followed in entering and leaving a regulated
area.
(3) Prohibited statements. No statement shall appear on or near any
required sign, label, or instruction that contradicts or detracts from
the effect of any required warning, information, or instruction.
(4) Training and indoctrination. (i) Each employee prior to being
authorized to enter a regulated area, shall receive a training and
indoctrination program including, but not necessarily limited to:
(A) The nature of the carcinogenic hazards of a carcinogen addressed
by this section, including local and systemic toxicity;
(B) The specific nature of the operation involving a carcinogen
addressed by this section that could result in exposure;
(C) The purpose for and application of the medical surveillance
program, including, as appropriate, methods of self-examination;
(D) The purpose for and application of decontamination practices and
purposes;
(E) The purpose for and significance of emergency practices and
procedures;
(F) The employee's specific role in emergency procedures;
(G) Specific information to aid the employee in recognition and
evaluation of conditions and situations which may result in the release
of a carcinogen addressed by this section;
[[Page 76]]
(H) The purpose for and application of specific first aid procedures
and practices;
(I) A review of this section at the employee's first training and
indoctrination program and annually thereafter.
(ii) Specific emergency procedures shall be prescribed, and posted,
and employees shall be familiarized with their terms, and rehearsed in
their application.
(iii) All materials relating to the program shall be provided upon
request to authorized representatives of the Assistant Secretary and the
Director.
(f) [Reserved]
(g) Medical surveillance. At no cost to the employee, a program of
medical surveillance shall be established and implemented for employees
considered for assignment to enter regulated areas, and for authorized
employees.
(1) Examinations. (i) Before an employee is assigned to enter a
regulated area, a preassignment physical examination by a physician
shall be provided. The examination shall include the personal history of
the employee, family and occupational background, including genetic and
environmental factors.
(ii) Authorized employees shall be provided periodic physical
examinations, not less often than annually, following the preassignment
examination.
(iii) In all physical examinations, the examining physician shall
consider whether there exist conditions of increased risk, including
reduced immunological competence, those undergoing treatment with
steroids or cytotoxic agents, pregnancy, and cigarette smoking.
(2) Records. (i) Employers of employees examined pursuant to this
paragraph shall cause to be maintained complete and accurate records of
all such medical examinations. Records shall be maintained for the
duration of the employee's employment.
(ii) Records required by this paragraph shall be provided upon
request to employees, designated representatives, and the Assistant
Secretary in accordance with 29 CFR 1910.1020 (a) through (e) and (g)
through (i). These records shall also be provided upon request to the
Director.
(iii) Any physician who conducts a medical examination required by
this paragraph shall furnish to the employer a statement of the
employee's suitability for employment in the specific exposure.
[61 FR 9242, Mar. 7, 1996, as amended at 63 FR 1286, Jan. 8, 1998; 63 FR
20099, Apr. 23, 1998; 70 FR 1141, Jan. 5, 2005; 71 FR 16672, Apr. 3,
2006; 73 FR 75584, Dec. 2, 2008; 76 FR 33608, June 8, 2011; 76 FR 80740,
Dec. 27, 2011; 77 FR 17779, Mar. 26, 2012]
Sec. 1910.1004 alpha-Naphthylamine.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1005 [Reserved]
Sec. 1910.1006 Methyl chloromethyl ether.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1007 3,'-Dichlorobenzidine (and its salts).
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1008 bis-Chloromethyl ether.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1009 beta-Naphthylamine.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1010 Benzidine.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1011 4-Aminodiphenyl.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1012 Ethyleneimine.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1013 beta-Propiolactone.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
[[Page 77]]
Sec. 1910.1014 2-Acetylaminofluorene.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1015 4-Dimethylaminoazobenzene.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1016 N-Nitrosodimethylamine.
SeeSec. 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Sec. 1910.1017 Vinyl chloride.
(a) Scope and application. (1) This section includes requirements
for the control of employee exposure to vinyl chloride (chloroethene),
Chemical Abstracts Service Registry No. 75014.
(2) This section applies to the manufacture, reaction, packaging,
repackaging, storage, handling or use of vinyl chloride or polyvinyl
chloride, but does not apply to the handling or use of fabricated
products made of polyvinyl chloride.
(3) This section applies to the transportation of vinyl chloride or
polyvinyl chloride except to the extent that the Department of
Transportation may regulate the hazards covered by this section.
(b) Definitions--(1) Action level means a concentration of vinyl
chloride of 0.5 ppm averaged over an 8-hour work day.
(2) Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or his
designee.
(3) Authorized person means any person specifically authorized by
the employer whose duties require him to enter a regulated area or any
person entering such an area as a designated representative of employees
for the purpose of exercising an opportunity to observe monitoring and
measuring procedures.
(4) Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health and Human Services, or his
designee.
(5) Emergency means any occurrence such as, but not limited to,
equipment failure, or operation of a relief device which is likely to,
or does, result in massive release of vinyl chloride.
(6) Fabricated product means a product made wholly or partly from
polyvinyl chloride, and which does not require further processing at
temperatures, and for times, sufficient to cause mass melting of the
polyvinyl chloride resulting in the release of vinyl chloride.
(7) Hazardous operation means any operation, procedure, or activity
where a release of either vinyl chloride liquid or gas might be expected
as a consequence of the operation or because of an accident in the
operation, which would result in an employee exposure in excess of the
permissible exposure limit.
(8) OSHA Area Director means the Director for the Occupational
Safety and Health Administration Area Office having jurisdiction over
the geographic area in which the employer's establishment is located.
(9) Polyvinyl chloride means polyvinyl chloride homopolymer or
copolymer before such is converted to a fabricated product.
(10) Vinyl chloride means vinyl chloride monomer.
(c) Permissible exposure limit. (1) No employee may be exposed to
vinyl chloride at concentrations greater than 1 ppm averaged over any 8-
hour period, and
(2) No employee may be exposed to vinyl chloride at concentrations
greater than 5 ppm averaged over any period not exceeding 15 minutes.
(3) No employee may be exposed to vinyl chloride by direct contact
with liquid vinyl chloride.
(d) Monitoring. (1) A program of initial monitoring and measurement
shall be undertaken in each establishment to determine if there is any
employee exposed, without regard to the use of respirators, in excess of
the action level.
(2) Where a determination conducted under paragraph (d)(1) of this
section shows any employee exposures, without regard to the use of
respirators, in excess of the action level, a program for determining
exposures for each such employee shall be established. Such a program:
[[Page 78]]
(i) Must be repeated at least quarterly for any employee exposed,
without regard to the use of respirators, in excess of the permissible
exposure limit.
(ii) Must be repeated not less than every 6 months for any employee
exposed without regard to the use of respirators, at or above the action
level.
(iii) May be discontinued for any employee only when at least two
consecutive monitoring determinations, made not less than 5 working days
apart, show exposures for that employee at or below the action level.
(3) Whenever there has been a production, process or control change
which may result in an increase in the release of vinyl chloride, or the
employer has any other reason to suspect that any employee may be
exposed in excess of the action level, a determination of employee
exposure under paragraph (d)(1) of this section shall be performed.
(4) The method of monitoring and measurement shall have an accuracy
(with a confidence level of 95 percent) of not less than plus or minus
50 percent from 0.25 through 0.5 ppm, plus or minus 35 percent from over
0.5 ppm through 1.0 ppm, and plus or minus 25 percent over 1.0 ppm.
(Methods meeting these accuracy requirements are available in the
``NIOSH Manual of Analytical Methods'').
(5) Employees or their designated representatives shall be afforded
reasonable opportunity to observe the monitoring and measuring required
by this paragraph.
(e) Regulated area. (1) A regulated area shall be established where:
(i) Vinyl chloride or polyvinyl chloride is manufactured, reacted,
repackaged, stored, handled or used; and
(ii) Vinyl chloride concentrations are in excess of the permissible
exposure limit.
(2) Access to regulated areas shall be limited to authorized
persons.
(f) Methods of compliance. Employee exposures to vinyl chloride
shall be controlled to at or below the permissible exposure limit
provided in paragraph (c) of this section by engineering, work practice,
and personal protective controls as follows:
(1) Feasible engineering and work practice controls shall
immediately be used to reduce exposures to at or below the permissible
exposure limit.
(2) Wherever feasible engineering and work practice controls which
can be instituted immediately are not sufficient to reduce exposures to
at or below the permissible exposure limit, they shall nonetheless be
used to reduce exposures to the lowest practicable level, and shall be
supplemented by respiratory protection in accordance with paragraph (g)
of this section. A program shall be established and implemented to
reduce exposures to at or below the permissible exposure limit, or to
the greatest extent feasible, solely by means of engineering and work
practice controls, as soon as feasible.
(3) Written plans for such a program shall be developed and
furnished upon request for examination and copying to authorized
representatives of the Assistant Secretary and the Director. Such plans
must be updated at least annually.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph.
(2) Respirator program. The employer must implement a respiratory
protection program in accordanceSec. 1910.134 (b) through (d) (except
(d)(1)(iii), and (d)(3)(iii)(B)(1) and (2)), and (f) through (m) which
covers each employee required by this section to use a respirator.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide an organic vapor cartridge that has a service life of at
least one hour when using a chemical cartridge respirator at vinyl
chloride concentrations up to 10 ppm.
(C) Select a canister that has a service life of at least four hours
when using a powered air-purifying respirator having a hood, helmet, or
full or half facepiece, or a gas mask with a front-or back-mounted
canister, at
[[Page 79]]
vinyl chloride concentrations up to 25 ppm.
(ii) When air-purifying respirators are used:
(A) Air-purifying canisters or cartridges must be replaced prior to
the expiration of their service life or the end of the shift in which
they are first used, whichever occurs first.
(B) A continuous-monitoring and alarm system must be provided when
concentrations of vinyl chloride could reasonably exceed the allowable
concentrations for the devices in use. Such a system must be used to
alert employees when vinyl chloride concentrations exceed the allowable
concentrations for the devices in use.
(h) Hazardous operations. (1) Employees engaged in hazardous
operations, including entry of vessels to clean polyvinyl chloride
residue from vessel walls, shall be provided and required to wear and
use;
(i) Respiratory protection in accordance with paragraphs (c) and (g)
of this section; and
(ii) Protective garments to prevent skin contact with liquid vinyl
chloride or with polyvinyl chloride residue from vessel walls. The
protective garments shall be selected for the operation and its possible
exposure conditions.
(2) Protective garments shall be provided clean and dry for each
use.
(i) Emergency situations. A written operational plan for emergency
situations shall be developed for each facility storing, handling, or
otherwise using vinyl chloride as a liquid or compressed gas.
Appropriate portions of the plan shall be implemented in the event of an
emergency. The plan shall specifically provide that:
(1) Employees engaged in hazardous operations or correcting
situations of existing hazardous releases shall be equipped as required
in paragraph (h) of this section;
(2) Other employees not so equipped shall evacuate the area and not
return until conditions are controlled by the methods required in
paragraph (f) of this section and the emergency is abated.
(j) Training. Each employee engaged in vinyl chloride or polyvinyl
chloride operations shall be provided training in a program relating to
the hazards of vinyl chloride and precautions for its safe use.
(1) The program shall include:
(i) The nature of the health hazard from chronic exposure to vinyl
chloride including specifically the carcinogenic hazard;
(ii) The specific nature of operations which could result in
exposure to vinyl chloride in excess of the permissible limit and
necessary protective steps;
(iii) The purpose for, proper use, and limitations of respiratory
protective devices;
(iv) The fire hazard and acute toxicity of vinyl chloride, and the
necessary protective steps;
(v) The purpose for and a description of the monitoring program;
(vi) The purpose for, and a description of, the medical surveillance
program;
(vii) Emergency procedures;
(viii) Specific information to aid the employee in recognition of
conditions which may result in the release of vinyl chloride; and
(ix) A review of this standard at the employee's first training and
indoctrination program, and annually thereafter.
(2) All materials relating to the program shall be provided upon
request to the Assistant Secretary and the Director.
(k) Medical surveillance. A program of medical surveillance shall be
instituted for each employee exposed, without regard to the use of
respirators, to vinyl chloride in excess of the action level. The
program shall provide each such employee with an opportunity for
examinations and tests in accordance with this paragraph. All medical
examinations and procedures shall be performed by or under the
supervision of a licensed physician, and shall be provided without cost
to the employee.
(1) At the time of initial assignment, or upon institution of
medical surveillance;
(i) A general physical examination shall be performed, with specific
attention to detecting enlargement of liver, spleen or kidneys, or
dysfunction in these organs, and for abnormalities in skin, connective
tissues and the pulmonary system (See appendix A).
[[Page 80]]
(ii) A medical history shall be taken, including the following
topics:
(A) Alcohol intake;
(B) Past history of hepatitis;
(C) Work history and past exposure to potential hepatotoxic agents,
including drugs and chemicals;
(D) Past history of blood transfusions; and
(E) Past history of hospitalizations.
(iii) A serum specimen shall be obtained and determinations made of:
(A) Total bilirubin;
(B) Alkaline phosphatase;
(C) Serum glutamic oxalacetic transaminase (SGOT);
(D) Serum glutamic pyruvic transaminase (SGPT); and
(E) Gamma glustamyl transpeptidase.
(2) Examinations must be provided in accordance with this paragraph
at least annually.
(3) Each employee exposed to an emergency shall be afforded
appropriate medical surveillance.
(4) A statement of each employee's suitability for continued
exposure to vinyl chloride including use of protective equipment and
respirators, shall be obtained from the examining physician promptly
after any examination. A copy of the physician's statement shall be
provided each employee.
(5) If any employee's health would be materially impaired by
continued exposure, such employee shall be withdrawn from possible
contact with vinyl chloride.
(6) Laboratory analyses for all biological specimens included in
medical examination shall be performed by accredited laboratories.
(7) If the examining physician determines that alternative medical
examinations to those required by paragraph (k)(1) of this section will
provide at least equal assurance of detecting medical conditions
pertinent to the exposure to vinyl chloride, the employer may accept
such alternative examinations as meeting the requirements of paragraph
(k)(1) of this section, if the employer obtains a statement from the
examining physician setting forth the alternative examinations and the
rationale for substitution. This statement shall be available upon
request for examination and copying to authorized representatives of the
Assistant Secretary and the Director.
(l) Communication of hazards--(1) Hazard communication--general. (i)
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard Communication Standard (HCS)
(Sec. 1910.1200) for vinyl chloride and polyvinyl chloride.
(ii) In classifying the hazards of vinyl chloride at least the
following hazards are to be addressed: Cancer; central nervous system
effects; liver effects; blood effects; and flammability.
(iii) Employers shall include vinyl chloride in the hazard
communication program established to comply with the HCS (Sec.
1910.1200). Employers shall ensure that each employee has access to
labels on containers of vinyl chloride and to safety data sheets, and is
trained in accordance with the requirements of HCS and paragraph (j) of
this section.
(2) Signs. (i) The employer shall post entrances to regulated areas
with legible signs bearing the legend:
DANGER
VINYL CHLORIDE
MAY CAUSE CANCER
AUTHORIZED PERSONNEL ONLY
(ii) The employer shall post signs at areas containing hazardous
operations or where emergencies currently exist. The signs shall be
legible and bear the legend:
DANGER
VINYL CHLORIDE
MAY CAUSE CANCER
WEAR RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(iii) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (l)(2)(i) of this section:
CANCER-SUSPECT AGENT AREA
AUTHORIZED PERSONNEL ONLY
(iv) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (l)(2)(ii) of this section:
CANCER-SUSPECT AGENT IN THIS AREA
PROTECTIVE EQUIPMENT REQUIRED
AUTHORIZED PERSONNEL ONLY
[[Page 81]]
(3) Labels. (i) In addition to the other requirements in this
paragraph (l), the employer shall ensure that labels for containers of
polyvinyl chloride resin waste from reactors or other waste contaminated
with vinyl chloride are legible and include the following information:
CONTAMINATED WITH VINYL CHLORIDE
MAY CAUSE CANCER
(ii) Prior to June 1, 2015, employers may include the following
information on labels of containers of polyvinyl chloride resin waste
from reactors or other waste contaminated with vinyl chloride in lieu of
the labeling requirements in paragraphs (l)(3)(i) of this section:
CONTAMINATED WITH VINYL CHLORIDE
CANCER-SUSPECT AGENT
(4) Prior to June 1, 2015, employers may include the following
information for containers of polyvinyl chloride in lieu of the labeling
requirements in paragraphs (l)(1)(i) of this section:
POLYVINYL CHLORIDE (OR TRADE NAME)
Contains
VINYL CHLORIDE
VINYL CHLORIDE IS A CANCER-SUSPECT AGENT
(5)(i) Prior to June 1, 2015, employers may include either the
following information in either paragraph (l)(5)(i) or (l)(5)(ii) of
this section on containers of vinyl chloride in lieu of the labeling
requirements in paragraph (l)(1)(i) of this section:
VINYL CHLORIDE
EXTREMELY FLAMMABLE GAS UNDER PRESSURE
CANCER-SUSPECT AGENT
(ii) In accordance with 49 CFR Parts 170-189, with the additional
legend applied near the label or placard:
CANCER-SUSPECT AGENT
(6) No statement shall appear on or near any required sign, label,
or instruction which contradicts or detracts from the effect of any
required warning, information, or instruction.
(m) Records. (1) All records maintained in accordance with this
section shall include the name and social security number of each
employee where relevant.
(2) Records of required monitoring and measuring and medical records
shall be provided upon request to employees, designated representatives,
and the Assistant Secretary in accordance with 29 CFR 1910.1020 (a)
through (e) and (g) through (i). These records shall be provided upon
request to the Director. Authorized personnel rosters shall also be
provided upon request to the Assistant Secretary and the Director.
(i) Monitoring and measuring records shall:
(A) State the date of such monitoring and measuring and the
concentrations determined and identify the instruments and methods used;
(B) Include any additional information necessary to determine
individual employee exposures where such exposures are determined by
means other than individual monitoring of employees; and
(C) Be maintained for not less than 30 years.
(ii) [Reserved]
(iii) Medical records shall be maintained for the duration of the
employment of each employee plus 20 years, or 30 years, whichever is
longer.
Appendix A toSec. 1910.1017--Supplementary Medical Information
When required tests under paragraph (k)(1) of this section show
abnormalities, the tests should be repeated as soon as practicable,
preferably within 3 to 4 weeks. If tests remain abnormal, consideration
should be given to withdrawal of the employee from contact with vinyl
chloride, while a more comprehensive examination is made.
Additional tests which may be useful:
A. For kidney dysfunction: urine examination for albumin, red blood
cells, and exfoliative abnormal cells.
B. Pulmonary system: Forced vital capacity, Forced expiratory volume
at 1 second, and chest roentgenogram (posterior-anterior, 14 x 17
inches).
C. Additional serum tests: Lactic acid dehydrogenase, lactic acid
dehydrogenase isoenzyme, protein determination, and protein
electrophoresis.
[[Page 82]]
D. For a more comprehensive examination on repeated abnormal serum
tests: Hepatitis B antigen, and liver scanning.
[39 FR 35896, Oct. 4, 1974; 39 FR 41848, Dec. 3, 1974, as amended at 40
FR 13211, Mar. 25, 1975. Redesignated at 40 FR 23072, May 28, 1975 and
amended at 43 FR 49751, Oct. 24, 1978; 45 FR 35282, May 23, 1980; 54 FR
24334, June 7, 1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13,
1996; 63 FR 1286, Jan. 8, 1998; 70 FR 1141, Jan. 5, 2005; 71 FR 16672,
16673, Apr. 3, 2006; 71 FR 50188, Aug. 24, 2006; 73 FR 75585, Dec. 12,
2008; 76 FR 33608, June 8, 2011; 77 FR 17779, Mar. 26, 2012]
Sec. 1910.1018 Inorganic arsenic.
(a) Scope and application. This section applies to all occupational
exposures to inorganic arsenic except that this section does not apply
to employee exposures in agriculture or resulting from pesticide
application, the treatment of wood with preservatives or the utilization
of arsenically preserved wood.
(b) Definitions. Action level means a concentration of inorganic
arsenic of 5 micrograms per cubic meter of air (5 [micro]g/m\3\)
averaged over any eight (8) hour period.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the
employer whose duties require the person to enter a regulated area, or
any person entering such an area as a designated representative of
employees for the purpose of exercising the right to observe monitoring
and measuring procedures under paragraph (e) of this section.
Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health and Human Services, or
designee.
Inorganic arsenic means copper aceto- arsenite and all inorganic
compounds containing arsenic except arsine, measured as arsenic (As).
(c) Permissible exposure limit. The employer shall assure that no
employee is exposed to inorganic arsenic at concentrations greater than
10 micrograms per cubic meter of air (10 [micro]g/m\3\), averaged over
any 8-hour period.
(d) [Reserved]
(e) Exposure monitoring--(1) General. (i) Determinations of airborne
exposure levels shall be made from air samples that are representative
of each employee's exposure to inorganic arsenic over an eight (8) hour
period.
(ii) For the purposes of this section, employee exposure is that
exposure which would occur if the employee were not using a respirator.
(iii) The employer shall collect full shift (for at least 7
continuous hours) personal samples including at least one sample for
each shift for each job classification in each work area.
(2) Initial monitoring. Each employer who has a workplace or work
operation covered by this standard shall monitor each such workplace and
work operation to accurately determine the airborne concentration of
inorganic arsenic to which employees may be exposed.
(3) Frequency. (i) If the initial monitoring reveals employee
exposure to be below the action level the measurements need not be
repeated except as otherwise provided in paragraph (e)(4) of this
section.
(ii) If the initial monitoring, required by this section, or
subsequent monitoring reveals employee exposure to be above the
permissible exposure limit, the employer shall repeat monitoring at
least quarterly.
(iii) If the initial monitoring, required by this section, or
subsequent monitoring reveals employee exposure to be above the action
level and below the permissible exposure limit the employer shall repeat
monitoring at least every six months.
(iv) The employer shall continue monitoring at the required
frequency until at least two consecutive measurements, taken at least
seven (7) days apart, are below the action level at which time the
employer may discontinue monitoring for that employee until such time as
any of the events in paragraph (e)(4) of this section occur.
(4) Additional monitoring. Whenever there has been a production,
process, control or personal change which may result in new or
additional exposure to inorganic arsenic, or whenever the employer has
any other reason to suspect a change which may result in new or
[[Page 83]]
additional exposures to inorganic arsenic, additional monitoring which
complies with paragraph (e) of this section shall be conducted.
(5) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each affected employee of these results either
individually in writing or by posting the results in an appropriate
location that is accessible to affected employees.
(ii) Whenever the results indicate that the representative employee
exposure exceeds the permissible exposure limit, the employer shall
include in the written notice a statement that the permissible exposure
limit was exceeded and a description of the corrective action taken to
reduce exposure to or below the permissible exposure limit.
(6) Accuracy of measurement. (i) The employer shall use a method of
monitoring and measurement which has an accuracy (with a confidence
level of 95 percent) of not less than plus or minus 25 percent for
concentrations of inorganic arsenic greater than or equal to 10
[micro]g/m\3\.
(ii) The employer shall use a method of monitoring and measurement
which has an accuracy (with confidence level of 95 percent) of not less
than plus or minus 35 percent for concentrations of inorganic arsenic
greater than 5 [micro]g/m\3\ but less than 10 [micro]g/m\3\.
(f) Regulated area--(1) Establishment. The employer shall establish
regulated areas where worker exposures to inorganic arsenic, without
regard to the use of respirators, are in excess of the permissible
limit.
(2) Demarcation. Regulated areas shall be demarcated and segregated
from the rest of the workplace in any manner that minimizes the number
of persons who will be exposed to inorganic arsenic.
(3) Access. Access to regulated areas shall be limited to authorized
persons or to persons otherwise authorized by the Act or regulations
issued pursuant thereto to enter such areas.
(4) Provision of respirators. All persons entering a regulated area
shall be supplied with a respirator, selected in accordance with
paragraph (h)(2) of this section.
(5) Prohibited activities. The employer shall assure that in
regulated areas, food or beverages are not consumed, smoking products,
chewing tobacco and gum are not used and cosmetics are not applied,
except that these activities may be conducted in the lunchrooms, change
rooms and showers required under paragraph (m) of this section. Drinking
water may be consumed in the regulated area.
(g) Methods of compliance--(1) Controls. (i) The employer shall
institute at the earliest possible time but not later than December 31,
1979, engineering and work practice controls to reduce exposures to or
below the permissible exposure limit, except to the extent that the
employer can establish that such controls are not feasible.
(ii) Where engineering and work practice controls are not sufficient
to reduce exposures to or below the permissible exposure limit, they
shall nonetheless be used to reduce exposures to the lowest levels
achievable by these controls and shall be supplemented by the use of
respirators in accordance with paragraph (h) of this section and other
necessary personal protective equipment. Employee rotation is not
required as a control strategy before respiratory protection is
instituted.
(2) Compliance Program. (i) The employer shall establish and
implement a written program to reduce exposures to or below the
permissible exposure limit by means of engineering and work practice
controls.
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each operation in which inorganic arsenic is
emitted; e.g. machinery used, material processed, controls in place,
crew size, operating procedures and maintenance practices;
(B) Engineering plans and studies used to determine methods selected
for controlling exposure to inorganic arsenic;
(C) A report of the technology considered in meeting the permissible
exposure limit;
(D) Monitoring data;
(E) A detailed schedule for implementation of the engineering
controls and
[[Page 84]]
work practices that cannot be implemented immediately and for the
adaption and implementation of any additional engineering and work
practices necessary to meet the permissible exposure limit;
(F) Whenever the employer will not achieve the permissible exposure
limit with engineering controls and work practices by December 31, 1979,
the employer shall include in the compliance plan an analysis of the
effectiveness of the various controls, shall install engineering
controls and institute work practices on the quickest schedule feasible,
and shall include in the compliance plan and implement a program to
minimize the discomfort and maximize the effectiveness of respirator
use; and
(G) Other relevant information.
(iii) Written plans for such a program shall be submitted upon
request to the Assistant Secretary and the Director, and shall be
available at the worksite for examination and copying by the Assistant
Secretary, Director, any affected employee or authorized employee
representatives.
(iv) The plans required by this paragraph must be revised and
updated at least annually to reflect the current status of the program.
(h) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
or work-practice controls.
(ii) Work operations, such as maintenance and repair activities, for
which the employer establishes that engineering and work-practice
controls are not feasible.
(iii) Work operations for which engineering and work-practice
controls are not yet sufficient to reduce employee exposures to or below
the permissible exposure limit.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii)), and (f) through (m), which covers each
employee required by this section to use a respirator.
(ii) If an employee exhibits breathing difficulty during fit testing
or respirator use, they must be examined by a physician trained in
pulmonary medicine to determine whether they can use a respirator while
performing the required duty.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Ensure that employees do not use half mask respirators for
protection against arsenic trichloride because it is absorbed rapidly
through the skin.
(C) Provide HEPA filters for powered and non-powered air-purifying
respirators.
(D) Select for employee use:
(1) Air-purifying respirators that have a combination HEPA filter
with an appropriate gas-sorbent cartridge or canister when the
employee's exposure exceeds the permissible exposure level for inorganic
arsenic and the relevant limit for other gases.
(2) Front-or back-mounted gas masks equipped with HEPA filters and
acid gas canisters or any full facepiece supplied-air respirators when
the inorganic arsenic concentration is at or below 500 mg/m\3\; and half
mask air-purifying respirators equipped with HEPA filters and acid gas
cartridges when the inorganic arsenic concentration is at or below 100
[mu]g/m\3\.
(ii) Employees required to use respirators may choose, and the
employer must provide, a powered air-purifying respirator if it will
provide proper protection. In addition, the employer must provide a
combination dust and acid-gas respirator to employees who are exposed to
gases over the relevant exposure limits.
(i) [Reserved]
(j) Protective work clothing and equipment--(1) Provision and use.
Where the possibility of skin or eye irritation from inorganic arsenic
exists, and for all workers working in regulated areas, the employer
shall provide at no cost
[[Page 85]]
to the employee and assure that employees use appropriate and clean
protective work clothing and equipment such as, but not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, and shoes or coverlets;
(iii) Face shields or vented goggles when necessary to prevent eye
irritation, which comply with the requirements ofSec. 1910.133(a) (2)-
(6); and
(iv) Impervious clothing for employees subject to exposure to
arsenic trichloride.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required in paragraph (j) (1) of this section in a
freshly laundered and dry condition at least weekly, and daily if the
employee works in areas where exposures are over 100 [micro]g/m\3\ of
inorganic arsenic or in areas where more frequent washing is needed to
prevent skin irritation.
(ii) The employer shall clean, launder, or dispose of protective
clothing required by paragraph (j) (1) of this section.
(iii) The employer shall repair or replace the protective clothing
and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change rooms
prescribed in paragraph (m) (1) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a closed
container in the change-room which prevents dispersion of inorganic
arsenic outside the container.
(vi) The employer shall inform in writing any person who cleans or
launders clothing required by this section, of the potentially harmful
effects including the carcinogenic effects of exposure to inorganic
arsenic.
(vii) Labels on contaminated protective clothing and equipment.
(A) The employer shall ensure that the containers of contaminated
protective clothing and equipment in the workplace or which are to be
removed from the workplace are labeled and that the labels include the
following information:
DANGER: CONTAMINATED WITH INORGANIC ARSENIC. MAY CAUSE CANCER. DO NOT
REMOVE DUST BY BLOWING OR SHAKING. DISPOSE OF INORGANIC ARSENIC
CONTAMINATED WASH WATER IN ACCORDANCE WITH APPLICABLE LOCAL, STATE OR
FEDERAL REGULATIONS.
(B) Prior to June 1, 2015, employers may include the following
information on containers of protective clothing and equipment in lieu
of the labeling requirements in paragraphs (j)(2)(vii) of this section:
CAUTION: Clothing contaminated with inorganic arsenic; do not remove
dust by blowing or shaking. Dispose of inorganic arsenic contaminated
wash water in accordance with applicable local, State or Federal
regulations.
(viii) The employer shall prohibit the removal of inorganic arsenic
from protective clothing or equipment by blowing or shaking.
(k) Housekeeping--(1) Surfaces. All surfaces shall be maintained as
free as practicable of accumulations of inorganic arsenic.
(2) Cleaning floors. Floors and other accessible surfaces
contaminated with inorganic arsenic may not be cleaned by the use of
compressed air, and shoveling and brushing may be used only where
vacuuming or other relevant methods have been tried and found not to be
effective.
(3) Vacuuming. Where vacuuming methods are selected, the vacuums
shall be used and emptied in a manner to minimize the reentry of
inorganic arsenic into the workplace.
(4) Housekeeping plan. A written housekeeping and maintenance plan
shall be kept which shall list appropriate frequencies for carrying out
housekeeping operations, and for cleaning and maintaining dust
collection equipment. The plan shall be available for inspection by the
Assistant Secretary.
(5) Maintenance of equipment. Periodic cleaning of dust collection
and ventilation equipment and checks of their effectiveness shall be
carried out to maintain the effectiveness of the system and a notation
kept of the last check of effectiveness and cleaning or maintenance.
(l) [Reserved]
[[Page 86]]
(m) Hygiene facilities and practices--(1) Change rooms. The employer
shall provide for employees working in regulated areas or subject to the
possibility of skin or eye irritation from inorganic arsenic, clean
change rooms equipped with storage facilities for street clothes and
separate storage facilities for protective clothing and equipment in
accordance with 29 CFR 1910.141(e).
(2) Showers. (i) The employer shall assure that employees working in
regulated areas or subject to the possibility of skin or eye irritation
from inorganic arsenic shower at the end of the work shift.
(ii) The employer shall provide shower facilities in accordance with
Sec. 1910.141(d)(3).
(3) Lunchrooms. (i) The employer shall provide for employees working
in regulated areas, lunchroom facilities which have a temperature
controlled, positive pressure, filtered air supply, and which are
readily accessible to employees working in regulated areas.
(ii) The employer shall assure that employees working in the
regulated area or subject to the possibility of skin or eye irritation
from exposure to inorganic arsenic wash their hands and face prior to
eating.
(4) Lavatories. The employer shall provide lavatory facilities which
comply withSec. 1910.141(d) (1) and (2).
(5) Vacuuming clothes. The employer shall provide facilities for
employees working in areas where exposure, without regard to the use of
respirators, exceeds 100 [micro]g/m\3\ to vacuum their protective
clothing and clean or change shoes worn in such areas before entering
change rooms, lunchrooms or shower rooms required by paragraph (j) of
this section and shall assure that such employees use such facilities.
(6) Avoidance of skin irritation. The employer shall assure that no
employee is exposed to skin or eye contact with arsenic trichloride, or
to skin or eye contact with liquid or particulate inorganic arsenic
which is likely to cause skin or eye irritation.
(n) Medical surveillance--(1) General--(i) Employees covered. The
employer shall institute a medical surveillance program for the
following employees:
(A) All employees who are or will be exposed above the action level,
without regard to the use of respirators, at least 30 days per year; and
(B) All employees who have been exposed above the action level,
without regard to respirator use, for 30 days or more per year for a
total of 10 years or more of combined employment with the employer or
predecessor employers prior to or after the effective date of this
standard. The determination of exposures prior to the effective date of
this standard shall be based upon prior exposure records, comparison
with the first measurements taken after the effective date of this
standard, or comparison with records of exposures in areas with similar
processes, extent of engineering controls utilized and materials used by
that employer.
(ii) Examination by physician. The employer shall assure that all
medical examinations and procedures are performed by or under the
supervision of a licensed physician, and shall be provided without cost
to the employee, without loss of pay and at a reasonable time and place.
(2) Initial examinations. By December 1, 1978, for employees
initially covered by the medical provisions of this section, or
thereafter at the time of initial assignment to an area where the
employee is likely to be exposed over the action level at least 30 days
per year, the employer shall provide each affected employee an
opportunity for a medical examination, including at least the following
elements:
(i) A work history and a medical history which shall include a
smoking history and the presence and degree of respiratory symptoms such
as breathlessness, cough, sputum production and wheezing.
(ii) A medical examination which shall include at least the
following:
(A) A standard posterior-anterior chest x-ray;
(B) A nasal and skin examination; and
(C) Other examinations which the physician believes appropriate
because of the employees exposure to inorganic arsenic or because of
required respirator use.
(3) Periodic examinations. (i) Examinations must be provided in
accordance with this paragraph at least annually.
[[Page 87]]
(ii) Whenever a covered employee has not taken the examinations
specified in paragraphs (n)(2)(i) and (n)(2)(ii) of this section within
six (6) months preceding the termination of employment, the employer
shall provide such examinations to the employee upon termination of
employment.
(4) Additional examinations. If the employee for any reason develops
signs or symptoms commonly associated with exposure to inorganic arsenic
the employer shall provide an appropriate examination and emergency
medical treatment.
(5) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and its appendices;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's representative exposure level or anticipated
exposure level;
(iv) A description of any personal protective equipment used or to
be used; and
(v) Information from previous medical examinations of the affected
employee which is not readily available to the examining physician.
(6) Physician's written opinion. (i) The employer shall obtain a
written opinion from the examining physician which shall include:
(A) The results of the medical examination and tests performed;
(B) The physician's opinion as to whether the employee has any
detected medical conditions which would place the employee at increased
risk of material impairment of the employee's health from exposure to
inorganic arsenic;
(C) Any recommended limitations upon the employee's exposure to
inorganic arsenic or upon the use of protective clothing or equipment
such as respirators; and
(D) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
which require further explanation or treatment.
(ii) The employer shall instruct the physician not to reveal in the
written opinion specific findings or diagnoses unrelated to occupational
exposure.
(iii) The employer shall provide a copy of the written opinion to
the affected employee.
(o) Employee information and training--(1) Training program. (i) The
employer shall train each employee who is subject to exposure to
inorganic arsenic above the action level without regard to respirator
use, or for whom there is the possibility of skin or eye irritation from
inorganic arsenic, in accordance with the requirements of this section.
The employer shall institute a training program and ensure employee
participation in the program.
(ii) The training program shall be provided by October 1, 1978, for
employees covered by this provision, at the time of initial assignment
for those subsequently covered by this provision, and at least annually
for other covered employees thereafter; and the employer shall assure
that each employee is informed of the following:
(A) The information contained in appendix A;
(B) The quantity, location, manner of use, storage, sources of
exposure, and the specific nature of operations which could result in
exposure to inorganic arsenic as well as any necessary protective steps;
(C) The purpose, proper use, and limitation of respirators;
(D) The purpose and a description of the medical surveillance
program as required by paragraph (n) of this section;
(E) The engineering controls and work practices associated with the
employee's job assignment; and
(F) A review of this standard.
(2) Access to training materials. (i) The employer shall make
readily available to all affected employees a copy of this standard and
its appendices.
(ii) The employer shall provide; upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(p) Communication of hazards--(1) Hazard communication--General. (i)
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard
[[Page 88]]
Communication Standard (HCS) (Sec. 1910.1200) for inorganic arsenic.
(ii) In classifying the hazards of inorganic arsenic at least the
following hazards are to be addressed: Cancer; liver effects; skin
effects; respiratory irritation; nervous system effects; and acute
toxicity effects.
(iii) Employers shall include inorganic arsenic in the hazard
communication program established to comply with the HCS (Sec.
1910.1200). Employers shall ensure that each employee has access to
labels on containers of inorganic arsenic and to safety data sheets, and
is trained in accordance with the requirements of HCS and paragraph (o)
of this section.
(iv) The employer shall ensure that no statement appears on or near
any sign or label required by this paragraph (p) which contradicts or
detracts from the meaning of the required sign or label.
(2) Signs. (i) The employer shall post signs demarcating regulated
areas bearing the legend:
DANGER
INORGANIC ARSENIC
MAY CAUSE CANCER
DO NOT EAT, DRINK OR SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(ii) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (p)(2)(i) of this section:
DANGER
INORGANIC ARSENIC
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
NO SMOKING OR EATING
RESPIRATOR REQUIRED
(iii) The employer shall ensure that signs required by this
paragraph (p) are illuminated and cleaned as necessary so that the
legend is readily visible.
(3)(i) Prior to June 1, 2015, in lieu of the labeling requirements
in paragraphs (p)(1)(i) of this section, employers may apply
precautionary labels to all shipping and storage containers of inorganic
arsenic, and to all products containing inorganic arsenic, bearing the
following legend:
DANGER
CONTAINS INORGANIC ARSENIC
CANCER HAZARD
HARMFUL IF INHALED OR SWALLOWED
USE ONLY WITH ADEQUATE VENTILATION OR RESPIRATORY PROTECTION
(ii) Labels are not required when the inorganic arsenic in the
product is bound in such a manner so as to make unlikely the possibility
of airborne exposure to inorganic arsenic. (Possible examples of
products not requiring labels are semiconductors, light emitting diodes
and glass.)
(q) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and maintain an accurate record of all monitoring required by
paragraph (e) of this section.
(ii) This record shall include:
(A) The date(s), number, duration location, and results of each of
the samples taken, including a description of the sampling procedure
used to determine representative employee exposure where applicable;
(B) A description of the sampling and analytical methods used and
evidence of their accuracy;
(C) The type of respiratory protective devices worn, if any;
(D) Name, social security number, and job classification of the
employees monitored and of all other employees whose exposure the
measurement is intended to represent; and
(E) The environmental variables that could affect the measurement of
the employee's exposure.
(iii) The employer shall maintain these monitoring records for at
least 40 years or for the duration of employment plus 20 years,
whichever, is longer.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (n) of this section.
(ii) This record shall include:
(A) The name, social security number, and description of duties of
the employee;
(B) A copy of the physician's written opinions;
(C) Results of any exposure monitoring done for that employee and
the representative exposure levels supplied to the physician; and
(D) Any employee medical complaints related to exposure to inorganic
arsenic.
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(iii) The employer shall in addition keep, or assure that the
examining physician keeps, the following medical records;
(A) A copy of the medical examination results including medical and
work history required under paragraph (n) of this section;
(B) A description of the laboratory procedures and a copy of any
standards or guidelines used to interpret the test results or references
to that information;
(C) The initial X-ray;
(D) The X-rays for the most recent 5 years; and
(E) Any X-rays with a demonstrated abnormality and all subsequent X-
rays;
(iv) The employer shall maintain or assure that the physician
maintains those medical records for at least 40 years, or for the
duration of employment plus 20 years whichever is longer.
(3) Availability. (i) The employer shall make available upon request
all records required to be maintained by paragraph (q) of this section
to the Assistant Secretary and the Director for examination and copying.
(ii) Records required by this paragraph shall be provided upon
request to employees, designated representatives, and the Assistant
Secretary in accordance with 29 CFR 1910.1020 (a) through (e) and (g)
through (i).
(4) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by this section.
(ii) The employer shall also comply with any additional requirements
involving the transfer of records set in 29 CFR 1910.1020(h).
(r) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to inorganic arsenic conducted pursuant to paragraph (e) of
this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to inorganic arsenic requires entry into
an area where the use of respirators, protective clothing, or equipment
is required, the employer shall provide the observer with and assure the
use of such respirators, clothing, and such equipment, and shall require
the observer to comply with all other applicable safety and health
procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled to;
(A) Receive an explanation of the measurement procedures;
(B) Observe all steps related to the monitoring of inorganic arsenic
performed at the place of exposure; and
(C) Record the results obtained or receive copies of the results
when returned by the laboratory.
(s) Appendices. The information contained in the appendices to this
section is not intended by itself, to create any additional obligations
not otherwise imposed by this standard nor detract from any existing
obligation.
Appendix A toSec. 1910.1018--Inorganic Arsenic Substance Information
Sheet
i. substance identification
A. Substance. Inorganic Arsenic.
B. Definition. Copper acetoarsenite, arsenic and all inorganic
compounds containing arsenic except arsine, measured as arsenic (As).
C. Permissible Exposure Limit. 10 micrograms per cubic meter of air
as determined as an average over an 8-hour period. No employee may be
exposed to any skin or eye contact with arsenic trichloride or to skin
or eye contact likely to cause skin or eye irritation.
D. Regulated Areas. Only employees authorized by your employer
should enter a regulated area.
ii. health hazard data
A. Comments. The health hazard of inorganic arsenic is high.
B. Ways in which the chemical affects your body. Exposure to
airborne concentrations of inorganic arsenic may cause lung cancer, and
can be a skin irritant. Inorganic arsenic may also affect your body if
swallowed. One compound in particular, arsenic trichloride, is
especially dangerous because it can be absorbed readily through the
skin. Because inorganic arsenic is a poison, you should wash your hands
thoroughly prior to eating or smoking.
iii. protective clothing and equipment
A. Respirators. Respirators will be provided by your employer at no
cost to you for routine use if your employer is in the process of
implementing engineering and work practice controls or where engineering
and work
[[Page 90]]
practice controls are not feasible or insufficient. You must wear
respirators for non-routine activities or in emergency situations where
you are likely to be exposed to levels of inorganic arsenic in excess of
the permissible exposure limit. Since how well your respirator fits your
face is very important, your employer is required to conduct fit tests
to make sure the respirator seals properly when you wear it. These tests
are simple and rapid and will be explained to you during training
sessions.
B. Protective clothing. If you work in a regulated area, your
employer is required to provide at no cost to you, and you must wear,
appropriate, clean, protective clothing and equipment. The purpose of
this equipment is to prevent you from bringing to your home arsenic-
contaminated dust and to protect your body from repeated skin contact
with inorganic arsenic likely to cause skin irritation. This clothing
should include such items as coveralls or similar full-body clothing,
gloves, shoes or coverlets, and aprons. Protective equipment should
include face shields or vented goggles, where eye irritation may occur.
y
iv. hygiene facilities and practices
You must not eat, drink, smoke, chew gum or tobacco, or apply
cosmetics in the regulated area, except that drinking water is
permitted. If you work in a regulated area your employer is required to
provide lunchrooms and other areas for these purposes.
If you work in a regulated area, your employer is required to
provide showers, washing facilities, and change rooms. You must wash
your face, and hands before eating and must shower at the end of the
work shift. Do not take used protective clothing out of change rooms
without your employer's permission. Your employer is required to provide
for laundering or cleaning of your protective clothing.
v. signs and labels
Your employer is required to post warning signs and labels for your
protection. Signs must be posted in regulated areas. The signs must warn
that a cancer hazard is present, that only authorized employees may
enter the area, and that no smoking or eating is allowed, and that
respirators must be worn.
vi. medical examinations
If your exposure to arsenic is over the Action Level (5 [mu]g/
m\3\)--(including all persons working in regulated areas) at least 30
days per year, or you have been exposed to arsenic for more than 10
years over the Action Level, your employer is required to provide you
with a medical examination. The examination shall be every 6 months for
employees over 45 years old or with more than 10 years exposure over the
Action Level and annually for other covered employees. The medical
examination must include a medical history; a chest x-ray; a skin
examination and a nasal examination. The examining physician will
provide a written opinion to your employer containing the results of
your medical exams. You should also receive a copy of this opinion. The
physician must not tell your employer any conditions he detects
unrelated to occupational exposure to arsenic but must tell you those
conditions.
vii. observation of monitoring
Your employer is required to monitor your exposure to arsenic and
you or your representatives are entitled to observe the monitoring
procedure. You are entitled to receive an explanation of the measurement
procedure, and to record the results obtained. When the monitoring
procedure is taking place in an area where respirators or personal
protective clothing and equipment are required to be worn, you must also
be provided with and must wear the protective clothing and equipment.
viii. access to records
You or your representative are entitled to records of your exposure
to inorganic arsenic and your medical examination records if you request
your employer to provide them.
ix. training and notification
Additional information on all of these items plus training as to
hazards of exposure to inorganic arsenic and the engineering and work
practice controls associated with your job will also be provided by your
employer. If you are exposed over the permissible exposure limit, your
employer must inform you of that fact and the actions he is taking to
reduce your exposures.
Appendix B toSec. 1910.1018--Substance Technical Guidelines
arsenic, arsenic trioxide, arsenic trichloride (three examples)
I. Physical and chemical properties
A. Arsenic (metal).
1. Formula: As.
2. Appearance: Gray metal.
3. Melting point: Sublimes without melting at 613C.
4. Specific Gravity: (H20=1):5.73.
5. Solubility in water: Insoluble.
B. Arsenic Trioxide.
1. Formula: As203, (As406).
2. Appearance: White powder.
3. Melting point: 315C.
4. Specific Gravity (H20=1):3.74.
5. Solubility in water: 3.7 grams in 100cc of water at 20c.
C. Arsenic Trichloride (liquid).
1. Formula: AsC13.
[[Page 91]]
2. Appearance: Colorless or pale yellow liquid.
3. Melting point: -8.5C.
4. Boiling point: 130.2C.
5. Specific Gravity (H20=1):2.16 at 20C.
6. Vapor Pressure: 10mm Hg at 23.5C.
7. Solubility in Water: Decomposes in water.
II. Fire, explosion and reactivity data.
A. Fire: Arsenic, arsenic Trioxide and Arsenic Trichloride are
nonflammable.
B. Reactivity:
1. Conditions Contributing to instability: Heat.
2. Incompatibility: Hydrogen gas can react with inorganic arsenic to
form the highly toxic gas arsine.
III. Monitoring and Measurement Procedures
Samples collected should be full shift (at least 7-hour) samples.
Sampling should be done using a personal sampling pump at a flow rate of
2 liters per minute. Samples should be collected on 0.8 micrometer pore
size membrane filter (37mm diameter). Volatile arsenicals such as
arsenic trichloride can be most easily collected in a midget bubbler
filled with 15 ml. of 0.1 N NaOH.
The method of sampling and analysis should have an accuracy of not
less than 25 percent (with a confidence limit of
95 percent) for 10 micrograms per cubic meter of air (10 [micro]g/m\3\)
and 35 percent (with a confidence limit of 95
percent) for concentrations of inorganic arsenic between 5 and 10
[micro]g/m\3\.
Appendix C toSec. 1910.1018--Medical Surveillance Guidelines
I. General
Medical examinations are to be provided for all employees exposed to
levels of inorganic arsenic above the action level (5 [micro]g/m\3\) for
at least 30 days per year (which would include among others, all
employees, who work in regulated areas). Examinations are also to be
provided to all employees who have had 10 years or more exposure above
the action level for more than 30 days per year while working for the
present or predecessor employer though they may no longer be exposed
above the level.
An initial medical examination is to be provided to all such
employees by December 1, 1978. In addition, an initial medical
examination is to be provided to all employees who are first assigned to
areas in which worker exposure will probably exceed 5 [micro]g/m\3\
(after the effective date of this standard) at the time of initial
assignment. In addition to its immediate diagnostic usefulness, the
initial examination will provide a baseline for comparing future test
results. The initial examination must include as a minimum the following
elements:
(1) A work and medical history, including a smoking history, and
presence and degree of respiratory symptoms such as breathlessness,
cough, sputum production, and wheezing;
(2) A 14 by 17 posterior-anterior chest X-ray;
(3) A nasal and skin examination; and
(4) Other examinations which the physician believes appropriate
because of the employee's exposure to inorganic arsenic or because of
required respirator use.
Periodic examinations are also to be provided to the employees
listed above. The periodic examinations shall be given annually for
those covered employees 45 years of age or less with fewer than 10 years
employment in areas where employee exposure exceeds the action level (5
[micro]g/m\3\). Periodic examinations need not include sputum cytology
and only an updated medical history is required.
Periodic examinations for other covered employees, shall be provided
every six (6) months. These examinations shall include all tests
required in the initial examination, except that the medical history
need only be updated.
The examination contents are minimum requirements. Additional tests
such as lateral and oblique X-rays or pulmonary function tests may be
useful. For workers exposed to three arsenicals which are associated
with lymphatic cancer, copper acetoarsenite, potassium arsenite, or
sodium arsenite the examination should also include palpation of
superficial lymph nodes and complete blood count.
ii. noncarcinogenic effects
The OSHA standard is based on minimizing risk of exposed workers
dying of lung cancer from exposure to inorganic arsenic. It will also
minimize skin cancer from such exposures.
The following three sections quoted from ``Occupational Diseases: A
Guide to Their Recognition'', Revised Edition, June 1977, National
Institute for Occupational Safety and Health is included to provide
information on the nonneoplastic effects of exposure to inorganic
arsenic. Such effects should not occur if the OSHA standards are
followed.
A. Local--Trivalent arsenic compounds are corrosive to the skin.
Brief contact has no effect but prolonged contact results in a local
hyperemia and later vesicular or pustular eruption. The moist mucous
membranes are most sensitive to the irritant action. Conjunctiva, moist
and macerated areas of skin, the eyelids, the angles of the ears, nose,
mouth, and respiratory mucosa are also vulnerable to the irritant
effects. The wrists are common sites of dermatitis, as are the genitalia
if personal hygiene is poor. Perforations of the nasal septum may
[[Page 92]]
occur. Arsenic trioxide and pentoxide are capable of producing skin
sensitization and contact dermatitis. Arsenic is also capable of
producing keratoses, especially of the palms and soles.
B. Systemic--The acute toxic effects of arsenic are generally seen
following ingestion of inorganic arsenical compounds. This rarely occurs
in an industrial setting. Symptoms develop within \1/2\ to 4 hours
following ingestion and are usually characterized by constriction of the
throat followed by dysphagia, epigastric pain, vomiting, and watery
diarrhea. Blood may appear in vomitus and stools. If the amount ingested
is sufficiently high, shock may develop due to severe fluid loss, and
death may ensue in 24 hours. If the acute effects are survived,
exfoliative dermatitis and peripheral neuritis may develop.
Cases of acute arsenical poisoning due to inhalation are exceedingly
rare in industry. When it does occur, respiratory tract symptoms--cough,
chest pain, dyspnea--giddiness, headache, and extreme general weakness
precede gastrointestinal symptoms. The acute toxic symptoms of trivalent
arsenical poisoning are due to severe inflammation of the mucous
membranes and greatly increased permeability of the blood capillaries.
Chronic arsenical poisoning due to ingestion is rare and generally
confined to patients taking prescribed medications. However, it can be a
concomitant of inhaled inorganic arsenic from swallowed sputum and
improper eating habits. Symptoms are weight loss, nausea and diarrhea
alternating with constipation, pigmentation and eruption of the skin,
loss of hair, and peripheral neuritis. Chronic hepatitis and cirrhosis
have been described. Polyneuritis may be the salient feature, but more
frequently there are numbness and parasthenias of ``glove and stocking''
distribution. The skin lesions are usually melanotic and keratotic and
may occasionally take the form of an intradermal cancer of the squamous
cell type, but without infiltrative properties. Horizontal white lines
(striations) on the fingernails and toenails are commonly seen in
chronic arsenical poisoning and are considered to be a diagnostic
accompaniment of arsenical polyneuritis.
Inhalation of inorganic arsenic compounds is the most common cause
of chronic poisoning in the industrial situation. This condition is
divided into three phases based on signs and symptoms.
First Phase: The worker complains of weakness, loss of appetite,
some nausea, occasional vomiting, a sense of heaviness in the stomach,
and some diarrhea.
Second Phase: The worker complains of conjunctivitis, a catarrhal
state of the mucous membranes of the nose, larynx, and respiratory
passage. Coryza, hoarseness, and mild tracheobronchitis may occur.
Perforation of the nasal septum is common, and is probably the most
typical lesion of the upper respiratory tract in occupational exposure
to arsenical dust. Skin lesions, eczematoid and allergic in type, are
common.
Third Phase: The worker complains of symptoms of peripheral
neuritis, initially of hands and feet, which is essentially sensory. In
more severe cases, motor paralyses occur; the first muscles affected are
usually the toe extensors and the peronei. In only the most severe cases
will paralysis of flexor muscles of the feet or of the extensor muscles
of hands occur.
Liver damage from chronic arsenical poisoning is still debated, and
as yet the question is unanswered. In cases of chronic and acute
arsenical poisoning, toxic effects to the myocardium have been reported
based on EKG changes. These findings, however, are now largely
discounted and the EKG changes are ascribed to electrolyte disturbances
concomitant with arsenicalism. Inhalation of arsenic trioxide and other
inorganic arsenical dusts does not give rise to radiological evidence or
pneumoconiosis. Arsenic does have a depressant effect upon the bone
marrow, with disturbances of both erythropoiesis and myelopoiesis.
Bibliography
Dinman, B. D. 1960. Arsenic; chronic human intoxication. J. Occup.
Med. 2:137.
Elkins, H. B. 1959. The Chemistry of Industrial Toxicology, 2nd ed.
John Wiley and Sons, New York.
Holmquist, L. 1951. Occupational arsenical dermatitis; a study among
employees at a copper-ore smelting works including investigations of
skin reactions to contact with arsenic compounds. Acta. Derm. Venereol.
(Supp. 26) 31:1.
Pinto, S. S., and C. M. McGill. 1953. Arsenic trioxide exposure in
industry. Ind. Med. Surg. 22:281.
Pinto, S. S., and K. W. Nelson. 1976. Arsenic toxicology and
industrial exposure. Annu. Rev. Pharmacol. Toxicol. 16:95.
Vallee, B. L., D. D. Ulmer, and W. E. C. Wacker. 1960. Arsenic
toxicology and biochemistry. AMA Arch. Indust. Health 21:132.
[39 FR 23502, June 27, 1974, as amended at 43 FR 19624, May 5, 1978; 43
FR 28472, June 30, 1978; 45 FR 35282, May 23, 1980; 54 FR 24334, June 7,
1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13, 1996; 61 FR 9245,
Mar. 7, 1996; 63 FR 1286, Jan. 8, 1998; 63 FR 33468, June 18, 1998; 70
FR 1141, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189,
Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77
FR 17780, Mar. 26, 2012]
[[Page 93]]
Sec. 1910.1020 Access to employee exposure and medical records.
(a) Purpose. The purpose of this section is to provide employees and
their designated representatives a right of access to relevant exposure
and medical records; and to provide representatives of the Assistant
Secretary a right of access to these records in order to fulfill
responsibilities under the Occupational Safety and Health Act. Access by
employees, their representatives, and the Assistant Secretary is
necessary to yield both direct and indirect improvements in the
detection, treatment, and prevention of occupational disease. Each
employer is responsible for assuring compliance with this section, but
the activities involved in complying with the access to medical records
provisions can be carried out, on behalf of the employer, by the
physician or other health care personnel in charge of employee medical
records. Except as expressly provided, nothing in this section is
intended to affect existing legal and ethical obligations concerning the
maintenance and confidentiality of employee medical information, the
duty to disclose information to a patient/employee or any other aspect
of the medical-care relationship, or affect existing legal obligations
concerning the protection of trade secret information.
(b) Scope and application. (1) This section applies to each general
industry, maritime, and construction employer who makes, maintains,
contracts for, or has access to employee exposure or medical records, or
analyses thereof, pertaining to employees exposed to toxic substances or
harmful physical agents.
(2) This section applies to all employee exposure and medical
records, and analyses thereof, of such employees, whether or not the
records are mandated by specific occupational safety and health
standards.
(3) This section applies to all employee exposure and medical
records, and analyses thereof, made or maintained in any manner,
including on an in-house of contractual (e.g., fee-for-service) basis.
Each employer shall assure that the preservation and access requirements
of this section are complied with regardless of the manner in which the
records are made or maintained.
(c) Definitions--(1) Access means the right and opportunity to
examine and copy.
(2) Analysis using exposure or medical records means any compilation
of data or any statistical study based at least in part on information
collected from individual employee exposure or medical records or
information collected from health insurance claims records, provided
that either the analysis has been reported to the employer or no further
work is currently being done by the person responsible for preparing the
analysis.
(3) Designated representative means any individual or organization
to whom an employee gives written authorization to exercise a right of
access. For the purposes of access to employee exposure records and
analyses using exposure or medical records, a recognized or certified
collective bargaining agent shall be treated automatically as a
designated representative without regard to written employee
authorization.
(4) Employee means a current employee, a former employee, or an
employee being assigned or transferred to work where there will be
exposure to toxic substances or harmful physical agents. In the case of
a deceased or legally incapacitated employee, the employee's legal
representative may directly exercise all the employee's rights under
this section.
(5) Employee exposure record means a record containing any of the
following kinds of information:
(i) Environmental (workplace) monitoring or measuring of a toxic
substance or harmful physical agent, including personal, area, grab,
wipe, or other form of sampling, as well as related collection and
analytical methodologies, calculations, and other background data
relevant to interpretation of the results obtained;
(ii) Biological monitoring results which directly assess the
absorption of a toxic substance or harmful physical agent by body
systems (e.g., the level of a chemical in the blood, urine, breath,
hair, fingernails, etc) but not including results which assess the
biological effect of a substance or agent or
[[Page 94]]
which assess an employee's use of alcohol or drugs;
(iii) Material safety data sheets indicating that the material may
pose a hazard to human health; or
(iv) In the absence of the above, a chemcial inventory or any other
record which reveals where and when used and the identity (e.g.,
chemical, common, or trade name) of a toxic substance or harmful
physical agent.
(6)(i) Employee medical record means a record concerning the health
status of an employee which is made or maintained by a physician, nurse,
or other health care personnel or technician, including:
(A) Medical and employment questionnaires or histories (including
job description and occupational exposures),
(B) The results of medical examinations (pre-employment, pre-
assignment, periodic, or episodic) and laboratory tests (including chest
and other X-ray examinations taken for the purposes of establishing a
base-line or detecting occupational illness, and all biological
monitoring not defined as an ``employee exposure record''),
(C) Medical opinions, diagnoses, progress notes, and
recommendations,
(D) First aid records,
(E) Descriptions of treatments and prescriptions, and
(F) Employee medical complaints.
(ii) ``Employee medical record'' does not include medical
information in the form of:
(A) Physical specimens (e.g., blood or urine samples) which are
routinely discarded as a part of normal medical practice; or
(B) Records concerning health insurance claims if maintained
separately from the employer's medical program and its records, and not
accessible to the employer by employee name or other direct personal
identifier (e.g., social security number, payroll number, etc.); or
(C) Records created solely in preparation for litigation which are
privileged from discovery under the applicable rules of procedure or
evidence; or
(D) Records concerning voluntary employee assistance programs
(alcohol, drug abuse, or personal counseling programs) if maintained
separately from the employer's medical program and its records.
(7) Employer means a current employer, a former employer, or a
successor employer.
(8) Exposure or exposed means that an employee is subjected to a
toxic substance or harmful physical agent in the course of employment
through any route of entry (inhalation, ingestion, skin contact or
absorption, etc.), and includes past exposure and potential (e.g.,
accidental or possible) exposure, but does not include situations where
the employer can demonstrate that the toxic substance or harmful
physical agent is not used, handled, stored, generated, or present in
the workplace in any manner different from typical non-occupational
situations.
(9) Health Professional means a physician, occupational health
nurse, industrial hygienist, toxicologist, or epidemiologist, providing
medical or other occupational health services to exposed employees.
(10) Record means any item, collection, or grouping of information
regardless of the form or process by which it is maintained (e.g., paper
document, microfiche, microfilm, X-ray film, or automated data
processing).
(11) Specific chemical identity means the chemical name, Chemical
Abstracts Service (CAS) Registry Number, or any other information that
reveals the precise chemical designation of the substance.
(12)(i) Specific written consent means a written authorization
containing the following:
(A) The name and signature of the employee authorizing the release
of medical information,
(B) The date of the written authorization,
(C) The name of the individual or organization that is authorized to
release the medical information,
(D) The name of the designated representative (individual or
organization) that is authorized to receive the released information,
(E) A general description of the medical information that is
authorized to be released,
(F) A general description of the purpose for the release of the
medical information, and
[[Page 95]]
(G) A date or condition upon which the written authorization will
expire (if less than one year).
(ii) A written authorization does not operate to authorize the
release of medical information not in existence on the date of written
authorization, unless the release of future information is expressly
authorized, and does not operate for more than one year from the date of
written authorization.
(iii) A written authorization may be revoked in writing
prospectively at any time.
(13) Toxic substance or harmful physical agent means any chemical
substance, biological agent (bacteria, virus, fungus, etc.), or physical
stress (noise, heat, cold, vibration, repetitive motion, ionizing and
non-ionizing radiation, hypo-or hyperbaric pressure, etc.) which:
(i) Is listed in the latest printed edition of the National
Institute for Occupational Safety and Health (NIOSH) Registry of Toxic
Effects of Chemical Substances (RTECS), which is incorporated by
reference as specified inSec. 1910.6; or
(ii) Has yielded positive evidence of an acute or chronic health
hazard in testing conducted by, or known to, the employer; or
(iii) Is the subject of a material safety data sheet kept by or
known to the employer indicating that the material may pose a hazard to
human health.
(14) Trade secret means any confidential formula, pattern, process,
device, or information or compilation of information that is used in an
employer's business and that gives the employer an opportunity to obtain
an advantage over competitors who do not know or use it.
(d) Preservation of records. (1) Unless a specific occupational
safety and health standard provides a different period of time, each
employer shall assure the preservation and retention of records as
follows:
(i) Employee medical records. The medical record for each employee
shall be preserved and maintained for at least the duration of
employment plus thirty (30) years, except that the following types of
records need not be retained for any specified period:
(A) Health insurance claims records maintained separately from the
employer's medical program and its records,
(B) First aid records (not including medical histories) of one-time
treatment and subsequent observation of minor scratches, cuts, burns,
splinters, and the like which do not involve medical treatment, loss of
consciousness, restriction of work or motion, or transfer to another
job, if made on-site by a non-physician and if maintained separately
from the employer's medical program and its records, and
(C) The medical records of employees who have worked for less than
(1) year for the employer need not be retained beyond the term of
employment if they are provided to the employee upon the termination of
employment.
(ii) Employee exposure records. Each employee exposure record shall
be preserved and maintained for at least thirty (30) years, except that:
(A) Background data to environmental (workplace) monitoring or
measuring, such as laboratory reports and worksheets, need only be
retained for one (1) year as long as the sampling results, the
collection methodology (sampling plan), a description of the analytical
and mathematical methods used, and a summary of other background data
relevant to interpretation of the results obtained, are retained for at
least thirty (30) years; and
(B) Material safety data sheets and paragraph (c)(5)(iv) records
concerning the identity of a substance or agent need not be retained for
any specified period as long as some record of the identity (chemical
name if known) of the substance or agent, where it was used, and when it
was used is retained for at least thirty (30) years;\1\ and
---------------------------------------------------------------------------
\1\ Material safety data sheets must be kept for those chemicals
currently in use that are effected by the Hazard Communication Standard
in accordance with 29 CFR 1910.1200(g).
---------------------------------------------------------------------------
(C) Biological monitoring results designated as exposure records by
specific occupational safety and health standards shall be preserved and
maintained as required by the specific standard.
(iii) Analyses using exposure or medical records. Each analysis
using exposure or medial records shall be preserved
[[Page 96]]
and maintained for at least thirty (30) years.
(2) Nothing in this section is intended to mandate the form, manner,
or process by which an employer preserves a record as long as the
information contained in the record is preserved and retrievable, except
that chest X-ray films shall be preserved in their original state.
(e) Access to records--(1) General. (i) Whenever an employee or
designated representative requests access to a record, the employer
shall assure that access is provided in a reasonable time, place, and
manner. If the employer cannot reasonably provide access to the record
within fifteen (15) working days, the employer shall within the fifteen
(15) working days apprise the employee or designated representative
requesting the record of the reason for the delay and the earliest date
when the record can be made available.
(ii) The employer may require of the requester only such information
as should be readily known to the requester and which may be necessary
to locate or identify the records being requested (e.g. dates and
locations where the employee worked during the time period in question).
(iii) Whenever an employee or designated representative requests a
copy of a record, the employer shall assure that either:
(A) A copy of the record is provided without cost to the employee or
representative,
(B) The necessary mechanical copying facilities (e.g., photocopying)
are made available without cost to the employee or representative for
copying the record, or
(C) The record is loaned to the employee or representative for a
reasonable time to enable a copy to be made.
(iv) In the case of an original X-ray, the employer may restrict
access to on-site examination or make other suitable arrangements for
the temporary loan of the X-ray.
(v) Whenever a record has been previously provided without cost to
an employee or designated representative, the employer may charge
reasonable, non-discriminatory administrative costs (i.e., search and
copying expenses but not including overhead expenses) for a request by
the employee or designated representative for additional copies of the
record, except that
(A) An employer shall not charge for an initial request for a copy
of new information that has been added to a record which was previously
provided; and
(B) An employer shall not charge for an initial request by a
recognized or certified collective bargaining agent for a copy of an
employee exposure record or an analysis using exposure or medical
records.
(vi) Nothing in this section is intended to preclude employees and
collective bargaining agents from collectively bargaining to obtain
access to information in addition to that available under this section.
(2) Employee and designated representative access--(i) Employee
exposure records. (A) Except as limited by paragraph (f) of this
section, each employer shall, upon request, assure the access to each
employee and designated representative to employee exposure records
relevant to the employee. For the purpose of this section, an exposure
record relevant to the employee consists of:
(1) A record which measures or monitors the amount of a toxic
substance or harmful physical agent to which the employee is or has been
exposed;
(2) In the absence of such directly relevant records, such records
of other employees with past or present job duties or working conditions
related to or similar to those of the employee to the extent necessary
to reasonably indicate the amount and nature of the toxic substances or
harmful physical agents to which the employee is or has been subjected,
and
(3) Exposure records to the extent necessary to reasonably indicate
the amount and nature of the toxic substances or harmful physical agents
at workplaces or under working conditions to which the employee is being
assigned or transferred.
(B) Requests by designated representatives for unconsented access to
employee exposure records shall be in writing and shall specify with
reasonable particularity:
(1) The records requested to be disclosed; and
[[Page 97]]
(2) The occupational health need for gaining access to these
records.
(ii) Employee medical records. (A) Each employer shall, upon
request, assure the access of each employee to employee medical records
of which the employee is the subject, except as provided in paragraph
(e)(2)(ii)(D) of this section.
(B) Each employer shall, upon request, assure the access of each
designated representative to the employee medical records of any
employee who has given the designated representative specific written
consent. appendix A to this section contains a sample form which may be
used to establish specific written consent for access to employee
medical records.
(C) Whenever access to employee medical records is requested, a
physician representing the employer may recommend that the employee or
designated representative:
(1) Consult with the physician for the purposes of reviewing and
discussing the records requested,
(2) Accept a summary of material facts and opinions in lieu of the
records requested, or
(3) Accept release of the requested records only to a physician or
other designated representative.
(D) Whenever an employee requests access to his or her employee
medical records, and a physician representing the employer believes that
direct employee access to information contained in the records regarding
a specific diagnosis of a terminal illness or a psychiatric condition
could be detrimental to the employee's health, the employer may inform
the employee that access will only be provided to a designated
representative of the employee having specific written consent, and deny
the employee's request for direct access to this information only. Where
a designated representative with specific written consent requests
access to information so withheld, the employer shall assure the access
of the designated representative to this information, even when it is
known that the designated representative will give the information to
the employee.
(E) A physician, nurse, or other responsible health care personnel
maintaining medical records may delete from requested medical records
the identity of a family member, personal friend, or fellow employee who
has provided confidential information concerning an employee's health
status.
(iii) Analyses using exposure or medical records. (A) Each employee
shall, upon request, assure the access of each employee and designated
representative to each analysis using exposure or medical records
concerning the employee's working conditions or workplace.
(B) Whenever access is requested to an analysis which reports the
contents of employee medical records by either direct identifier (name,
address, social security number, payroll number, etc.) or by information
which could reasonably be used under the circumstances indirectly to
identify specific employees (exact age, height, weight, race, sex, date
of initial employment, job title, etc.), the employer shall assure that
personal identifiers are removed before access is provided. If the
employer can demonstrate that removal of personal identifiers from an
analysis is not feasible, access to the personally identifiable portions
of the analysis need not be provided.
(3) OSHA access. (i) Each employer shall, upon request, and without
derogation of any rights under the Constitution or the Occupational
Safety and Health Act of 1970, 29 U.S.C. 651 et seq., that the employer
chooses to exercise, assure the prompt access of representatives of the
Assistant Secretary of Labor for Occupational Safety and Health to
employee exposure and medical records and to analyses using exposure or
medical records. Rules of agency practice and procedure governing OSHA
access to employee medical records are contained in 29 CFR 1913.10.
(ii) Whenever OSHA seeks access to personally identifiable employee
medical information by presenting to the employer a written access order
pursuant to 29 CFR 1913.10(d), the employer shall prominently post a
copy of the written access order and its accompanying cover letter for
at least fifteen (15) working days.
(f) Trade secrets. (1) Except as provided in paragraph (f)(2) of
this section, nothing in this section precludes an employer from
deleting from records
[[Page 98]]
requested by a health professional, employee, or designated
representative any trade secret data which discloses manufacturing
processes, or discloses the percentage of a chemical substance in
mixture, as long as the health professional, employee, or designated
representative is notified that information has been deleted. Whenever
deletion of trade secret information substantially impairs evaluation of
the place where or the time when exposure to a toxic substance or
harmful physical agent occurred, the employer shall provide alternative
information which is sufficient to permit the requesting party to
identify where and when exposure occurred.
(2) The employer may withhold the specific chemical identity,
including the chemical name and other specific identification of a toxic
substance from a disclosable record provided that:
(i) The claim that the information withheld is a trade secret can be
supported;
(ii) All other available information on the properties and effects
of the toxic substance is disclosed;
(iii) The employer informs the requesting party that the specific
chemical identity is being withheld as a trade secret; and
(iv) The specific chemical identity is made available to health
professionals, employees and designated representatives in accordance
with the specific applicable provisions of this paragraph.
(3) Where a treating physician or nurse determines that a medical
emergency exists and the specific chemical identity of a toxic substance
is necessary for emergency or first-aid treatment, the employer shall
immediately disclose the specific chemical identity of a trade secret
chemical to the treating physician or nurse, regardless of the existence
of a written statement of need or a confidentiality agreement. The
employer may require a written statement of need and confidentiality
agreement, in accordance with the provisions of paragraphs (f)(4) and
(f)(5), as soon as circumstances permit.
(4) In non-emergency situations, an employer shall, upon request,
disclose a specific chemical identity, otherwise permitted to be
withheld under paragraph (f)(2) of this section, to a health
professional, employee, or designated representative if:
(i) The request is in writing;
(ii) The request describes with reasonable detail one or more of the
following occupational health needs for the information:
(A) To assess the hazards of the chemicals to which employees will
be exposed;
(B) To conduct or assess sampling of the workplace atmosphere to
determine employee exposure levels;
(C) To conduct pre-assignment or periodic medical surveillance of
exposed employees;
(D) To provide medical treatment to exposed employees;
(E) To select or assess appropriate personal protective equipment
for exposed employees;
(F) To design or assess engineering controls or other protective
measures for exposed employees; and
(G) To conduct studies to determine the health effects of exposure.
(iii) The request explains in detail why the disclosure of the
specific chemical identity is essential and that, in lieu thereof, the
disclosure of the following information would not enable the health
professional, employee or designated representative to provide the
occupational health services described in paragraph (f)(4)(ii) of this
section:
(A) The properties and effects of the chemical;
(B) Measures for controlling workers' exposure to the chemical;
(C) Methods of monitoring and analyzing worker exposure to the
chemical; and,
(D) Methods of diagnosing and treating harmful exposures to the
chemical;
(iv) The request includes a description of the procedures to be used
to maintain the confidentiality of the disclosed information; and,
(v) The health professional, employee, or designated representative
and the employer or contractor of the services of the health
professional or designated representative agree in a written
confidentiality agreement that the health professional, employee or
designated representative will not use the trade secret information for
any purpose other than the health need(s)
[[Page 99]]
asserted and agree not to release the information under any
circumstances other than to OSHA, as provided in paragraph (f)(7) of
this section, except as authorized by the terms of the agreement or by
the employer.
(5) The confidentiality agreement authorized by paragraph (f)(4)(iv)
of this section:
(i) May restrict the use of the information to the health purposes
indicated in the written statement of need;
(ii) May provide for appropriate legal remedies in the event of a
breach of the agreement, including stipulation of a reasonable pre-
estimate of likely damages; and,
(iii) May not include requirements for the posting of a penalty
bond.
(6) Nothing in this section is meant to preclude the parties from
pursuing non-contractual remedies to the extent permitted by law.
(7) If the health professional, employee or designated
representative receiving the trade secret information decides that there
is a need to disclose it to OSHA, the employer who provided the
information shall be informed by the health professional prior to, or at
the same time as, such disclosure.
(8) If the employer denies a written request for disclosure of a
specific chemical identity, the denial must:
(i) Be provided to the health professional, employee or designated
representative within thirty days of the request;
(ii) Be in writing;
(iii) Include evidence to support the claim that the specific
chemical identity is a trade secret;
(iv) State the specific reasons why the request is being denied;
and,
(v) Explain in detail how alternative information may satisfy the
specific medical or occupational health need without revealing the
specific chemical identity.
(9) The health professional, employee, or designated representative
whose request for information is denied under paragraph (f)(4) of this
section may refer the request and the written denial of the request to
OSHA for consideration.
(10) When a heath professional employee, or designated
representative refers a denial to OSHA under paragraph (f)(9) of this
section, OSHA shall consider the evidence to determine if:
(i) The employer has supported the claim that the specific chemical
identity is a trade secret;
(ii) The health professional employee, or designated representative
has supported the claim that there is a medical or occupational health
need for the information; and
(iii) The health professional, employee or designated representative
has demonstrated adequate means to protect the confidentiality.
(11)(i) If OSHA determines that the specific chemical identity
requested under paragraph (f)(4) of this section is not a bona fide
trade secret, or that it is a trade secret but the requesting health
professional, employee or designated representatives has a legitimate
medical or occupational health need for the information, has executed a
written confidentiality agreement, and has shown adequate means for
complying with the terms of such agreement, the employer will be subject
to citation by OSHA.
(ii) If an employer demonstrates to OSHA that the execution of a
confidentiality agreement would not provide sufficient protection
against the potential harm from the unauthorized disclosure of a trade
secret specific chemical identity, the Assistant Secretary may issue
such orders or impose such additional limitations or conditions upon the
disclosure of the requested chemical information as may be appropriate
to assure that the occupational health needs are met without an undue
risk of harm to the employer.
(12) Notwithstanding the existence of a trade secret claim, an
employer shall, upon request, disclose to the Assistant Secretary any
information which this section requires the employer to make available.
Where there is a trade secret claim, such claim shall be made no later
than at the time the information is provided to the Assistant Secretary
so that suitable determinations of trade secret status can be made and
the necessary protections can be implemented.
[[Page 100]]
(13) Nothing in this paragraph shall be construed as requiring the
disclosure under any circumstances of process or percentage of mixture
information which is trade secret.
(g) Employee information. (1) Upon an employee's first entering into
employment, and at least annually thereafter, each employer shall inform
current employees covered by this section of the following:
(i) The existence, location, and availability of any records covered
by this section;
(ii) The person responsible for maintaining and providing access to
records; and
(iii) Each employee's rights of access to these records.
(2) Each employer shall keep a copy of this section and its
appendices, and make copies readily available, upon request, to
employees. The employer shall also distribute to current employees any
informational materials concerning this section which are made available
to the employer by the Assistant Secretary of Labor for Occupational
Safety and Health.
(h) Transfer of records. (1) Whenever an employer is ceasing to do
business, the employer shall transfer all records subject to this
section to the successor employer. The successor employer shall receive
and maintain these records.
(2) Whenever an employer is ceasing to do business and there is no
successor employer to receive and maintain the records subject to this
standard, the employer shall notify affected current employees of their
rights of access to records at least three (3) months prior to the
cessation of the employer's business.
(i) Appendices. The information contained in appendices A and B to
this section is not intended, by itself, to create any additional
obligations not otherwise imposed by this section nor detract from any
existing obligation.
Appendix A toSec. 1910.1020--Sample Authorization Letter for the
Release of Employee Medical Record Information to a Designated
Representative (Non-Mandatory)
I, ---------- (full name of worker/patient), hereby authorize ------
------ (individual or organization holding the medical records) to
release to ------------ (individual or organization authorized to
receive the medical information), the following medical information from
my personal medical records:
________________________________________________________________________
________________________________________________________________________
(Describe generally the information desired to be released)
I give my permission for this medical information to be used for the
following purpose:
________________________________________________________________________
________________________________________________________________________
but I do not give permission for any other use or re-disclosure of this
information.
Note: Several extra lines are provided below so that you can place
additional restrictions on this authorization letter if you want to. You
may, however, leave these lines blank. On the other hand, you may want
to (1) specify a particular expiration date for this letter (if less
than one year); (2) describe medical information to be created in the
future that you intend to be covered by this authorization letter; or
(3) describe portions of the medical information in your records which
you do not intend to be released as a result of this letter.)
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Full name of Employee or Legal Representative
________________________________________________________________________
Signature of Employee or Legal Representative
________________________________________________________________________
________________________________________________________________________
Date of Signature
Appendix B toSec. 1910.1020--Availability of NIOSH Registry of Toxic
Effects of Chemical Substances (RTECS) (Non-Mandatory)
The final regulation, 29 CFR 1910.20, applies to all employee
exposure and medical records, and analyses thereof, of employees exposed
to toxic substances or harmful physical agents (paragraph (b)(2)). The
term toxic substance or harmful physical agent is defined by paragraph
(c)(13) to encompass chemical substances, biological agents, and
physical stresses for which there is evidence of harmful health effects.
The regulation uses the latest printed edition of the National Institute
for Occupational Safety and Health (NIOSH) Registry of Toxic Effects of
Chemical Substances (RTECS) as one of the chief sources of information
as to whether evidence of harmful health effects exists. If a substance
is listed in the latest printed RTECS, the regulation applies to
exposure and medical records (and analyses of these
[[Page 101]]
records) relevant to employees exposed to the substance.
It is appropriate to note that the final regulation does not require
that employers purchase a copy of RTECS, and many employers need not
consult RTECS to ascertain whether their employee exposure or medical
records are subject to the rule. Employers who do not currently have the
latest printed edition of the NIOSH RTECS, however, may desire to obtain
a copy. The RTECS is issued in an annual printed edition as mandated by
section 20(a)(6) of the Occupational Safety and Health Act (29 U.S.C.
669(a)(6)).
The Introduction to the 1980 printed edition describes the RTECS as
follows:
``The 1980 edition of the Registry of Toxic Effects of Chemical
Substances, formerly known as the Toxic Substances list, is the ninth
revision prepared in compliance with the requirements of Section
20(a)(6) of the Occupational Safety and Health Act of 1970 (Public Law
91-596). The original list was completed on June 28, 1971, and has been
updated annually in book format. Beginning in October 1977, quarterly
revisions have been provided in microfiche. This edition of the Registry
contains 168,096 listings of chemical substances: 45,156 are names of
different chemicals with their associated toxicity data and 122,940 are
synonyms. This edition includes approximately 5,900 new chemical
compounds that did not appear in the 1979 Registry. (p. xi)
``The Registry's purposes are many, and it serves a variety of
users. It is a single source document for basic toxicity information and
for other data, such as chemical identifiers ad information necessary
for the preparation of safety directives and hazard evaluations for
chemical substances. The various types of toxic effects linked to
literature citations provide researchers and occupational health
scientists with an introduction to the toxicological literature, making
their own review of the toxic hazards of a given substance easier. By
presenting data on the lowest reported doses that produce effects by
several routes of entry in various species, the Registry furnishes
valuable information to those responsible for preparing safety data
sheets for chemical substances in the workplace. Chemical and production
engineers can use the Registry to identify the hazards which may be
associated with chemical intermediates in the development of final
products, and thus can more readily select substitutes or alternative
processes which may be less hazardous. Some organizations, including
health agencies and chemical companies, have included the NIOSH Registry
accession numbers with the listing of chemicals in their files to
reference toxicity information associated with those chemicals. By
including foreign language chemical names, a start has been made toward
providing rapid identification of substances produced in other
countries. (p. xi)
``In this edition of the Registry, the editors intend to identify
``all known toxic substances'' which may exist in the environment and to
provide pertinent data on the toxic effects from known doses entering an
organism by any route described. (p xi)
``It must be reemphasized that the entry of a substance in the
Registry does not automatically mean that it must be avoided. A listing
does mean, however, that the substance has the documented potential of
being harmful if misused, and care must be exercised to prevent tragic
consequences. Thus, the Registry lists many substances that are common
in everyday life and are in nearly every household in the United States.
One can name a variety of such dangerous substances: prescription and
non-prescription drugs; food additives; pesticide concentrates, sprays,
and dusts; fungicides; herbicides; paints; glazes, dyes; bleaches and
other household cleaning agents; alkalies; and various solvents and
diluents. The list is extensive because chemicals have become an
integral part of our existence.''
The RTECS printed edition may be purchased from the Superintendent
of Documents, U.S. Government Printing Office (GPO), Washington, DC
20402 (202-783-3238).
Some employers may desire to subscribe to the quarterly update to
the RTECS which is published in a microfiche edition. An annual
subscription to the quarterly microfiche may be purchased from the GPO
(Order the ``Microfiche Edition, Registry of Toxic Effects of Chemical
Substances''). Both the printed edition and the microfiche edition of
RTECS are available for review at many university and public libraries
throughout the country. The latest RTECS editions may also be examined
at the OSHA Technical Data Center, Room N2439--Rear, United States
Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210
(202-523-9700), or at any OSHA Regional or Area Office (See, major city
telephone directories under United States Government-Labor Department).
[53 FR 38163, Sept. 29, 1988; 53 FR 49981, Dec. 13, 1988, as amended at
54 FR 24333, June 7, 1989; 55 FR 26431, June 28, 1990; 61 FR 9235, Mar.
7, 1996. Redesignated at 61 FR 31430, June 20, 1996, as amended at 71 FR
16673, Apr. 3, 2006; 76 FR 33608, June 8, 2011]
Sec. 1910.1025 Lead.
(a) Scope and application. (1) This section applies to all
occupational exposure to lead, except as provided in paragraph (a)(2).
[[Page 102]]
(2) This section does not apply to the construction industry or to
agricultural operations covered by 29 CFR part 1928.
(b) Definitions. Action level means employee exposure, without
regard to the use of respirators, to an airborne concentration of lead
of 30 micrograms per cubic meter of air (30 [micro]g/m\3\) averaged over
an 8-hour period.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Director means the Director, National Institute for Occupational
Safety and Health (NIOSH), U.S. Department of Health, Education, and
Welfare, or designee.
Lead means metallic lead, all inorganic lead compounds, and organic
lead soaps. Excluded from this definition are all other organic lead
compounds.
(c) Permissible exposure limit (PEL). (1) The employer shall assure
that no employee is exposed to lead at concentrations greater than fifty
micrograms per cubic meter of air (50 [micro]g/m\3\) averaged over an 8-
hour period.
(2) If an employee is exposed to lead for more than 8 hours in any
work day, the permissible exposure limit, as a time weighted average
(TWA) for that day, shall be reduced according to the following formula:
Maximum permissible limit (in [micro]g/m\3\)=400/hours worked in the
day.
(3) When respirators are used to supplement engineering and work
practice controls to comply with the PEL and all the requirements of
paragraph (f) have been met, employee exposure, for the purpose of
determining whether the employer has complied with the PEL, may be
considered to be at the level provided by the protection factor of the
respirator for those periods the respirator is worn. Those periods may
be averaged with exposure levels during periods when respirators are not
worn to determine the employee's daily TWA exposure.
(d) Exposure monitoring--(1) General. (i) For the purposes of
paragraph (d), employee exposure is that exposure which would occur if
the employee were not using a respirator.
(ii) With the exception of monitoring under paragraph (d)(3), the
employer shall collect full shift (for at least 7 continuous hours)
personal samples including at least one sample for each shift for each
job classification in each work area.
(iii) Full shift personal samples shall be representative of the
monitored employee's regular, daily exposure to lead.
(2) Initial determination. Each employer who has a workplace or work
operation covered by this standard shall determine if any exployee may
be exposed to lead at or above the action level.
(3) Basis of initial determination. (i) The employer shall monitor
employee exposures and shall base initial determinations on the employee
exposure monitoring results and any of the following, relevant
considerations:
(A) Any information, observations, or calculations which would
indicate employee exposure to lead;
(B) Any previous measurements of airborne lead; and
(C) Any employee complaints of symptoms which may be attributable to
exposure to lead.
(ii) Monitoring for the initial determination may be limited to a
representative sample of the exposed employees who the employer
reasonably believes are exposed to the greatest airborne concentrations
of lead in the workplace.
(iii) Measurements of airborne lead made in the preceding 12 months
may be used to satisfy the requirement to monitor under paragraph
(d)(3)(i) if the sampling and analytical methods used meet the accuracy
and confidence levels of paragraph (d)(9) of this section.
(4) Positive initial determination and initial monitoring. (i) Where
a determination conducted under paragraphs (d) (2) and (3) of this
section shows the possibility of any employee exposure at or above the
action level, the employer shall conduct monitoring which is
representative of the exposure for each employee in the workplace who is
exposed to lead.
(ii) Measurements of airborne lead made in the preceding 12 months
may be used to satisfy this requirement if the sampling and analytical
methods
[[Page 103]]
used meet the accuracy and confidence levels of paragraph (d)(9) of this
section.
(5) Negative initial determination. Where a determination, conducted
under paragraphs (d) (2) and (3) of this section is made that no
employee is exposed to airborne concentrations of lead at or above the
action level, the employer shall make a written record of such
determination. The record shall include at least the information
specified in paragraph (d)(3) of this section and shall also include the
date of determination, location within the worksite, and the name and
social security number of each employee monitored.
(6) Frequency. (i) If the initial monitoring reveals employee
exposure to be below the action level the measurements need not be
repeated except as otherwise provided in paragraph (d)(7) of this
section.
(ii) If the initial determination or subsequent monitoring reveals
employee exposure to be at or above the action level but below the
permissible exposure limit the employer shall repeat monitoring in
accordance with this paragraph at least every 6 months. The employer
shall continue monitoring at the required frequency until at least two
consecutive measurements, taken at least 7 days apart, are below the
action level at which time the employer may discontinue monitoring for
that employee except as otherwise provided in paragraph (d)(7) of this
section.
(iii) If the initial monitoring reveals that employee exposure is
above the permissible exposure limit the employer shall repeat
monitoring quarterly. The employer shall continue monitoring at the
required frequency until at least two consecutive measurements, taken at
least 7 days apart, are below the PEL but at or above the action level
at which time the employer shall repeat monitoring for that employee at
the frequency specified in paragraph (d)(6)(ii), except as otherwise
provided in paragraph (d)(7) of this section.
(7) Additional monitoring. Whenever there has been a production,
process, control or personnel change which may result in new or
additional exposure to lead, or whenever the employer has any other
reason to suspect a change which may result in new or additional
exposures to lead, additional monitoring in accordance with this
paragraph shall be conducted.
(8) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each affected employee of these results either
individually in writing or by posting the results in an appropriate
location that is accessible to affected employees.
(ii) Whenever the results indicate that the representative employee
exposure, without regard to respirators, exceeds the permissible
exposure limit, the employer shall incude in the written notice a
statement that the permissible exposure limit was exceeded and a
description of the corrective action taken or to be taken to reduce
exposure to or below the permissible exposure limit.
(9) Accuracy of measurement. The employer shall use a method of
monitoring and analysis which has an accuracy (to a confidence level of
95%) of not less than plus or minus 20 percent for airborne
concentrations of lead equal to or greater than 30 [micro]g/m\3\.
(e) Methods of compliance--(1) Engineering and work practice
controls. (i) Where any employee is exposed to lead above the
permissible exposure limit for more than 30 days per year, the employer
shall implement engineering and work practice controls (including
administrative controls) to reduce and maintain employee exposure to
lead in accordance with the implementation schedule in Table I below,
except to the extent that the employer can demonstrate that such
controls are not feasible. Wherever the engineering and work practice
controls which can be instituted are not sufficient to reduce employee
exposure to or below the permissible exposure limit, the employer shall
nonetheless use them to reduce exposures to the lowest feasible level
and shall supplement them by the use of respiratory protection which
complies with the requirements of paragraph (f) of this section.
(ii) Where any employee is exposed to lead above the permissible
exposure limit, but for 30 days or less per year,
[[Page 104]]
the employer shall implement engineering controls to reduce exposures to
200 [micro]g/m\3\, but thereafter may implement any combination of
engineering, work practice (including administrative controls), and
respiratory controls to reduce and maintain employee exposure to lead to
or below 50 [micro]g/m\3\.
Table I
------------------------------------------------------------------------
Compliance dates: \1\ (50
Industry [micro]g/m\3\)
------------------------------------------------------------------------
Lead chemicals, secondary copper smelting July 19, 1996.
Nonferrous foundries..................... July 19, 1996. \2\
Brass and bronze ingot manufacture....... 6 years. \3\
------------------------------------------------------------------------
\1\ Calculated by counting from the date the stay on implementation of
paragraph (e)(1) was lifted by the U.S. Court of Appeals for the
District of Columbia, the number of years specified in the 1978 lead
standard and subsequent amendments for compliance with the PEL of 50
[micro]g/m\3\ for exposure to airborne concentrations of lead levels
for the particular industry.
\2\ Large nonferrous foundries (20 or more employees) are required to
achieve the PEL of 50 [micro]g/m\3\ by means of engineering and work
practice controls. Small nonferrous foundries (fewer than 20
employees) are required to achieve an 8-hour TWA of 75 [micro]g/m\3\
by such controls.
\3\ Expressed as the number of years from the date on which the Court
lifts the stay on the implementation of paragraph (e)(1) for this
industry for employers to achieve a lead in air concentration of 75
[micro]g/m\3\. Compliance with paragraph (e) in this industry is
determined by a compliance directive that incorporates elements from
the settlement agreement between OSHA and representatives of the
industry.
(2) Respiratory protection. Where engineering and work practice
controls do not reduce employee exposure to or below the 50 [micro]g/
m\3\ permissible exposure limit, the employer shall supplement these
controls with respirators in accordance with paragraph (f).
(3) Compliance program. (i) Each employer shall establish and
implement a written compliance program to reduce exposures to or below
the permissible exposure limit, and interim levels if applicable, solely
by means of engineering and work practice controls in accordance with
the implementation schedule in paragraph (e)(1).
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each operation in which lead is emitted; e.g.
machinery used, material processed, controls in place, crew size,
employee job responsibilities, operating procedures and maintenance
practices;
(B) A description of the specific means that will be employed to
achieve compliance, including engineering plans and studies used to
determine methods selected for controlling exposure to lead;
(C) A report of the technology considered in meeting the permissible
exposure limit;
(D) Air monitoring data which documents the source of lead
emissions;
(E) A detailed schedule for implementation of the program, including
documentation such as copies of purchase orders for equipment,
construction contracts, etc.;
(F) A work practice program which includes items required under
paragraphs (g), (h) and (i) of this regulation;
(G) An administrative control schedule required by paragraph (e)(6),
if applicable;
(H) Other relevant information.
(iii) Written programs shall be submitted upon request to the
Assistant Secretary and the Director, and shall be available at the
worksite for examination and copying by the Assistant Secretary,
Director, any affected employee or authorized employee representatives.
(iv) Written programs must be revised and updated at least annually
to reflect the current status of the program.
(4) Mechanical ventilation. (i) When ventilation is used to control
exposure, measurements which demonstrate the effectiveness of the system
in controlling exposure, such as capture velocity, duct velocity, or
static pressure shall be made at least every 3 months. Measurements of
the system's effectiveness in controlling exposure shall be made within
5 days of any change in production, process, or control which might
result in a change in employee exposure to lead.
(ii) Recirculation of air. If air from exhaust ventilation is
recirculated into the workplace, the employer shall assure that (A) the
system has a high efficiency filter with reliable back-up filter; and
(B) controls to monitor the concentration of lead in the return air and
to bypass the recirculation system automatically if it fails are
installed, operating, and maintained.
(5) Administrative controls. If administrative controls are used as
a means of reducing employees TWA exposure to lead, the employer shall
establish and
[[Page 105]]
implement a job rotation schedule which includes:
(i) Name or identification number of each affected employee;
(ii) Duration and exposure levels at each job or work station where
each affected employee is located; and
(iii) Any other information which may be useful in assessing the
reliability of administrative controls to reduce exposure to lead.
(f) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement engineering or work-
practice controls.
(ii) Work operations for which engineering and work-practice
controls are not sufficient to reduce employee exposures to or below the
permissible exposure limit.
(iii) Periods when an employee requests a respirator.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii)), and (f) through (m), which covers each
employee required by this section to use a respirator.
(ii) If an employee has breathing difficulty during fit testing or
respirator use, the employer must provide the employee with a medical
examination in accordance with paragraph (j)(3)(i)(C) of this section to
determine whether or not the employee can use a respirator while
performing the required duty.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide employees with full facepiece respirators instead of
half mask respirators for protection against lead aerosols that cause
eye or skin irritation at the use concentrations.
(C) Provide HEPA filters for powered and non-powered air-purifying
respirators.
(ii) Employers must provide employees with a powered air-purifying
respirator (PAPR) instead of a negative pressure respirator selected
according to paragraph (f)(3)(i) of this standard when an employee
chooses to use a PAPR and it provides adequate protection to the
employee as specified by paragraph (f)(3)(i) of this standard.
(g) Protective work clothing and equipment--(1) Provision and use.
If an employee is exposed to lead above the PEL, without regard to the
use of respirators or where the possibility of skin or eye irritation
exists, the employer shall provide at no cost to the employee and assure
that the employee uses appropriate protective work clothing and
equipment such as, but not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, hats, and shoes or disposable shoe coverlets; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment which complies withSec. 1910.133 of this Part.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required in paragraph (g)(1) of this section in a
clean and dry condition at least weekly, and daily to employees whose
exposure levels without regard to a respirator are over 200 [micro]g/
m\3\ of lead as an 8-hour TWA.
(ii) The employer shall provide for the cleaning, laundering, or
disposal of protective clothing and equipment required by paragraph
(g)(1) of this section.
(iii) The employer shall repair or replace required protective
clothing and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change rooms provided
for that purpose as prescribed in paragraph (i)(2) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a closed
container in the change-room which prevents dispersion of lead outside
the container.
(vi) The employer shall inform in writing any person who cleans or
launders protective clothing or equipment
[[Page 106]]
of the potentially harmful effects of exposure to lead.
(vii) Labeling of contaminated protective clothing and equipment.
(A) The employer shall ensure that labels of bags or containers of
contaminated protective clothing and equipment include the following
information:
DANGER: CLOTHING AND EQUIPMENT CONTAMINATED WITH LEAD. MAY DAMAGE
FERTILITY OR THE UNBORN CHILD. CAUSES DAMAGE TO THE CENTRAL NERVOUS
SYSTEM. DO NOT EAT, DRINK OR SMOKE WHEN HANDLING. DO NOT REMOVE DUST BY
BLOWING OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN
ACCORDANCE WITH APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
(B) Prior to June 1, 2015, employers may include the following
information on bags or containers of contaminated protective clothing
and equipment in lieu of the labeling requirements in paragraphs
(g)(2)(vii)(A) of this section:
CAUTION: CLOTHING CONTAMINATED WITH LEAD. DO NOT REMOVE DUST BY BLOWING
OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN ACCORDANCE WITH
APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
(viii) The employer shall prohibit the removal of lead from
protective clothing or equipment by blowing, shaking, or any other means
which disperses lead into the air.
(h) Housekeeping--(1) Surfaces. All surfaces shall be maintained as
free as practicable of accumulations of lead.
(2) Cleaning floors. (i) Floors and other surfaces where lead
accumulates may not be cleaned by the use of compressed air.
(ii) Shoveling, dry or wet sweeping, and brushing may be used only
where vacuuming or other equally effective methods have been tried and
found not to be effective.
(3) Vacuuming. Where vacuuming methods are selected, the vacuums
shall be used and emptied in a manner which minimizes the reentry of
lead into the workplace.
(i) Hygiene facilities and practices. (1) The employer shall assure
that in areas where employees are exposed to lead above the PEL, without
regard to the use of respirators, food or beverage is not present or
consumed, tobacco products are not present or used, and cosmetics are
not applied, except in change rooms, lunchrooms, and showers required
under paragraphs (i)(2) through (i)(4) of this section.
(2) Change rooms. (i) The employer shall provide clean change rooms
for employees who work in areas where their airborne exposure to lead is
above the PEL, without regard to the use of respirators.
(ii) The employer shall assure that change rooms are equipped with
separate storage facilities for protective work clothing and equipment
and for street clothes which prevent cross-contamination.
(3) Showers. (i) The employer shall assure that employees who work
in areas where their airborne exposure to lead is above the PEL, without
regard to the use of respirators, shower at the end of the work shift.
(ii) The employer shall provide shower facilities in accordance with
Sec. 1910.141 (d)(3) of this part.
(iii) The employer shall assure that employees who are required to
shower pursuant to paragraph (i)(3)(i) do not leave the workplace
wearing any clothing or equipment worn during the work shift.
(4) Lunchrooms. (i) The employer shall provide lunchroom facilities
for employees who work in areas where their airborne exposure to lead is
above the PEL, without regard to the use of respirators.
(ii) The employer shall assure that lunchroom facilities have a
temperature controlled, positive pressure, filtered air supply, and are
readily accessible to employees.
(iii) The employer shall assure that employees who work in areas
where their airborne exposure to lead is above the PEL without regard to
the use of a respirator wash their hands and face prior to eating,
drinking, smoking or applying cosmetics.
(iv) The employer shall assure that employees do not enter lunchroom
facilities with protective work clothing or equipment unless surface
lead dust has been removed by vacuuming, downdraft booth, or other
cleaning method.
[[Page 107]]
(5) Lavatories. The employer shall provide an adequate number of
lavatory facilities which comply withSec. 1910.141(d) (1) and (2) of
this part.
(j) Medical surveillance--(1) General. (i) The employer shall
institute a medical surveillance program for all employees who are or
may be exposed at or above the action level for more than 30 days per
year.
(ii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician.
(iii) The employer shall provide the required medical surveillance
including multiple physician review under paragraph (j)(3)(iii) without
cost to employees and at a reasonable time and place.
(2) Biological monitoring--(i) Blood lead and ZPP level sampling and
analysis. The employer shall make available biological monitoring in the
form of blood sampling and analysis for lead and zinc protoporphyrin
levels to each employee covered under paragraph (j)(1)(i) of this
section on the following schedule:
(A) At least every 6 months to each employee covered under paragraph
(j)(1)(i) of this section;
(B) At least every two months for each employee whose last blood
sampling and analysis indicated a blood lead level at or above 40
[micro]g/100 g of whole blood. This frequency shall continue until two
consecutive blood samples and analyses indicate a blood lead level below
40 [micro]g/100 g of whole blood; and
(C) At least monthly during the removal period of each employee
removed from exposure to lead due to an elevated blood lead level.
(ii) Follow-up blood sampling tests. Whenever the results of a blood
lead level test indicate that an employee's blood lead level is at or
above the numerical criterion for medical removal under paragraph
(k)(1)(i)(A) of this section, the employer shall provide a second
(follow-up) blood sampling test within two weeks after the employer
receives the results of the first blood sampling test.
(iii) Accuracy of blood lead level sampling and analysis. Blood lead
level sampling and analysis provided pursuant to this section shall have
an accuracy (to a confidence level of 95 percent) within plus or minus
15 percent or 6 [micro]g/100ml, whichever is greater, and shall be
conducted by a laboratory licensed by the Center for Disease Control,
United States Department of Health, Education and Welfare (CDC) or which
has received a satisfactory grade in blood lead proficiency testing from
CDC in the prior twelve months.
(iv) Employee notification. Within five working days after the
receipt of biological monitoring results, the employer shall notify in
writing each employee whose blood lead level is at or above 40 [micro]g/
100 g:
(A) Of that employee's blood lead level; and
(B) That the standard requires temporary medical removal with
Medical Removal Protection benefits when an employee's blood lead level
is at or above the numerical criterion for medical removal under
paragraph (k)(1)(i) of this section.
(3) Medical examinations and consultations--(i) Frequency. The
employer shall make available medical examinations and consultations to
each employee covered under paragraph (j)(1)(i) of this section on the
following schedule:
(A) At least annually for each employee for whom a blood sampling
test conducted at any time during the preceding 12 months indicated a
blood lead level at or above 40 [micro]g/100 g;
(B) Prior to assignment for each employee being assigned for the
first time to an area in which airborne concentrations of lead are at or
above the action level;
(C) As soon as possible, upon notification by an employee either
that the employee has developed signs or symptoms commonly associated
with lead intoxication, that the employee desires medical advice
concerning the effects of current or past exposure to lead on the
employee's ability to procreate a healthy child, or that the employee
has demonstrated difficulty in breathing during a respirator fitting
test or during use; and
(D) As medically appropriate for each employee either removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited pursuant to a final medical determination.
[[Page 108]]
(ii) Content. Medical examinations made available pursuant to
paragraph (j)(3)(i) (A) through (B) of this section shall include the
following elements:
(A) A detailed work history and a medical history, with particular
attention to past lead exposure (occupational and non-occupational),
personal habits (smoking, hygiene), and past gastrointestinal,
hematologic, renal, cardiovascular, reproductive and neurological
problems;
(B) A thorough physical examination, with particular attention to
teeth, gums, hematologic, gastrointestinal, renal, cardiovascular, and
neurological systems. Pulmonary status should be evaluated if
respiratory protection will be used;
(C) A blood pressure measurement;
(D) A blood sample and analysis which determines:
(1) Blood lead level;
(2) Hemoglobin and hematocrit determinations, red cell indices, and
examination of peripheral smear morphology;
(3) Zinc protoporphyrin;
(4) Blood urea nitrogen; and,
(5) Serum creatinine;
(E) A routine urinalysis with microscopic examination; and
(F) Any laboratory or other test which the examining physician deems
necessary by sound medical practice.
The content of medical examinations made available pursuant to paragraph
(j)(3)(i) (C) through (D) of this section shall be determined by an
examining physician and, if requested by an employee, shall include
pregnancy testing or laboratory evaluation of male fertility.
(iii) Multiple physician review mechanism. (A) If the employer
selects the initial physician who conducts any medical examination or
consultation provided to an employee under this section, the employee
may designate a second physician:
(1) To review any findings, determinations or recommendations of the
initial physician; and
(2) To conduct such examinations, consultations, and laboratory
tests as the second physician deems necessary to facilitate this review.
(B) The employer shall promptly notify an employee of the right to
seek a second medical opinion after each occasion that an initial
physician conducts a medical examination or consultation pursuant to
this section. The employer may condition its participation in, and
payment for, the multiple physician review mechanism upon the employee
doing the following within fifteen (15) days after receipt of the
foregoing notification, or receipt of the initial physician's written
opinion, whichever is later:
(1) The employee informing the employer that he or she intends to
seek a second medical opinion, and
(2) The employee initiating steps to make an appointment with a
second physician.
(C) If the findings, determinations or recommendations of the second
physician differ from those of the initial physician, then the employer
and the employee shall assure that efforts are made for the two
physicians to resolve any disagreement.
(D) If the two physicians have been unable to quickly resolve their
disagreement, then the employer and the employee through their
respective physicians shall designate a third physician:
(1) To review any findings, determinations or recommendations of the
prior physicians; and
(2) To conduct such examinations, consultations, laboratory tests
and discussions with the prior physicians as the third physician deems
necessary to resolve the disagreement of the prior physicians.
(E) The employer shall act consistent with the findings,
determinations and recommendations of the third physician, unless the
employer and the employee reach an agreement which is otherwise
consistent with the recommendations of at least one of the three
physicians.
(iv) Information provided to examining and consulting physicians.
(A) The employer shall provide an initial physician conducting a medical
examination or consultation under this section with the following
information:
(1) A copy of this regulation for lead including all Appendices;
(2) A description of the affected employee's duties as they relate
to the employee's exposure;
[[Page 109]]
(3) The employee's exposure level or anticipated exposure level to
lead and to any other toxic substance (if applicable);
(4) A description of any personal protective equipment used or to be
used;
(5) Prior blood lead determinations; and
(6) All prior written medical opinions concerning the employee in
the employer's possession or control.
(B) The employer shall provide the foregoing information to a second
or third physician conducting a medical examination or consultation
under this section upon request either by the second or third physician,
or by the employee.
(v) Written medical opinions. (A) The employer shall obtain and
furnish the employee with a copy of a written medical opinion from each
examining or consulting physician which contains the following
information:
(1) The physician's opinion as to whether the employee has any
detected medical condition which would place the employee at increased
risk of material impairment of the employee's health from exposure to
lead;
(2) Any recommended special protective measures to be provided to
the employee, or limitations to be placed upon the employee's exposure
to lead;
(3) Any recommended limitation upon the employee's use of
respirators, including a determination of whether the employee can wear
a powered air purifying respirator if a physician determines that the
employee cannot wear a negative pressure respirator; and
(4) The results of the blood lead determinations.
(B) The employer shall instruct each examining and consulting
physician to:
(1) Not reveal either in the written opinion, or in any other means
of communication with the employer, findings, including laboratory
results, or diagnoses unrelated to an employee's occupational exposure
to lead; and
(2) Advise the employee of any medical condition, occupational or
nonoccupational, which dictates further medical examination or
treatment.
(vi) Alternate Physician Determination Mechanisms. The employer and
an employee or authorized employee representative may agree upon the use
of any expeditious alternate physician determination mechanism in lieu
of the multiple physician review mechanism provided by this paragraph so
long as the alternate mechanism otherwise satisfies the requirements
contained in this paragraph.
(4) Chelation. (i) The employer shall assure that any person whom he
retains, employs, supervises or controls does not engage in prophylactic
chelation of any employee at any time.
(ii) If therapeutic or diagnostic chelation is to be performed by
any person in paragraph (j)(4)(i), the employer shall assure that it be
done under the supervision of a licensed physician in a clinical setting
with thorough and appropriate medical monitoring and that the employee
is notified in writing prior to its occurrence.
(k) Medical Removal Protection--(1) Temporary medical removal and
return of an employee--(i) Temporary removal due to elevated blood lead
levels. (A) The employer shall remove an employee from work having an
exposure to lead at or above the action level on each occasion that a
periodic and a follow-up blood sampling test conducted pursuant to this
section indicate that the employee's blood lead level is at or above 60
[micro]g/100 g of whole blood; and
(B) The employer shall remove an employee from work having an
exposure to lead at or above the action level on each occasion that the
average of the last three blood sampling tests conducted pursuant to
this section (or the average of all blood sampling tests conducted over
the previous six (6) months, whichever is longer) indicates that the
employee's blood lead level is at or above 50 [micro]g/100 g of whole
blood; provided, however, that an employee need not be removed if the
last blood sampling test indicates a blood lead level below 40 [micro]g/
100 g of whole blood.
(ii) Temporary removal due to a final medical determination. (A) The
employer shall remove an employee from work having an exposure to lead
at or above the action level on each occasion that a final medical
determination results in a medical finding, determination, or opinion
that the employee has a detected medical condition which places
[[Page 110]]
the employee at increased risk of material impairment to health from
exposure to lead.
(B) For the purposes of this section, the phrase ``final medical
determination'' shall mean the outcome of the multiple physician review
mechanism or alternate medical determination mechanism used pursuant to
the medical surveillance provisions of this section.
(C) Where a final medical determination results in any recommended
special protective measures for an employee, or limitations on an
employee's exposure to lead, the employer shall implement and act
consistent with the recommendation.
(iii) Return of the employee to former job status. (A) The employer
shall return an employee to his or her former job status:
(1) For an employee removed due to a blood lead level at or above 60
[micro]g/100 g, or due to an average blood lead level at or above 50
[micro]g/100 g, when two consecutive blood sampling tests indicate that
the employee's blood lead level is below 40 [micro]g/100 g of whole
blood;
(2) For an employee removed due to a final medical determination,
when a subsequent final medical determination results in a medical
finding, determination, or opinion that the employee no longer has a
detected medical condition which places the employee at increased risk
of material impairment to health from exposure to lead.
(B) For the purposes of this section, the requirement that an
employer return an employee to his or her former job status is not
intended to expand upon or restrict any rights an employee has or would
have had, absent temporary medical removal, to a specific job
classification or position under the terms of a collective bargaining
agreement.
(iv) Removal of other employee special protective measure or
limitations. The employer shall remove any limitations placed on an
employee or end any special protective measures provided to an employee
pursuant to a final medical determination when a subsequent final
medical determination indicates that the limitations or special
protective measures are no longer necessary.
(v) Employer options pending a final medical determination. Where
the multiple physician review mechanism, or alternate medical
determination mechanism used pursuant to the medical surveillance
provisions of this section, has not yet resulted in a final medical
determination with respect to an employee, the employer shall act as
follows:
(A) Removal. The employer may remove the employee from exposure to
lead, provide special protective measures to the employee, or place
limitations upon the employee, consistent with the medical findings,
determinations, or recommendations of any of the physicians who have
reviewed the employee's health status.
(B) Return. The employer may return the employee to his or her
former job status, end any special protective measures provided to the
employee, and remove any limitations placed upon the employee,
consistent with the medical findings, determinations, or recommendations
of any of the physicians who have reviewed the employee's health status,
with two exceptions. If
(1) the initial removal, special protection, or limitation of the
employee resulted from a final medical determination which differed from
the findings, determinations, or recommendations of the initial
physician or
(2) The employee has been on removal status for the preceding
eighteen months due to an elevated blood lead level, then the employer
shall await a final medical determination.
(2) Medical removal protection benefits--(i) Provision of medical
removal protection benefits. The employer shall provide to an employee
up to eighteen (18) months of medical removal protection benefits on
each occasion that an employee is removed from exposure to lead or
otherwise limited pursuant to this section.
(ii) Definition of medical removal protection benefits. For the
purposes of this section, the requirement that an employer provide
medical removal protection benefits means that the employer shall
maintain the earnings, seniority
[[Page 111]]
and other employment rights and benefits of an employee as though the
employee had not been removed from normal exposure to lead or otherwise
limited.
(iii) Follow-up medical surveillance during the period of employee
removal or limitation. During the period of time that an employee is
removed from normal exposure to lead or otherwise limited, the employer
may condition the provision of medical removal protection benefits upon
the employee's participation in follow-up medical surveillance made
available pursuant to this section.
(iv) Workers' compensation claims. If a removed employee files a
claim for workers' compensation payments for a lead-related disability,
then the employer shall continue to provide medical removal protection
benefits pending disposition of the claim. To the extent that an award
is made to the employee for earnings lost during the period of removal,
the employer's medical removal protection obligation shall be reduced by
such amount. The employer shall receive no credit for workers'
compensation payments received by the employee for treatment related
expenses.
(v) Other credits. The employer's obligation to provide medical
removal protection benefits to a removed employee shall be reduced to
the extent that the employee receives compensation for earnings lost
during the period of removal either from a publicly or employer-funded
compensation program, or receives income from employment with another
employer made possible by virtue of the employee's removal.
(vi) Employees whose blood lead levels do not adequately decline
within 18 months of removal. The employer shall take the following
measures with respect to any employee removed from exposure to lead due
to an elevated blood lead level whose blood lead level has not declined
within the past eighteen (18) months of removal so that the employee has
been returned to his or her former job status:
(A) The employer shall make available to the employee a medical
examination pursuant to this section to obtain a final medical
determination with respect to the employee;
(B) The employer shall assure that the final medical determination
obtained indicates whether or not the employee may be returned to his or
her former job status, and if not, what steps should be taken to protect
the employee's health;
(C) Where the final medical determination has not yet been obtained,
or once obtained indicates that the employee may not yet be returned to
his or her former job status, the employer shall continue to provide
medical removal protection benefits to the employee until either the
employee is returned to former job status, or a final medical
determination is made that the employee is incapable of ever safely
returning to his or her former job status.
(D) Where the employer acts pursuant to a final medical
determination which permits the return of the employee to his or her
former job status despite what would otherwise be an unacceptable blood
lead level, later questions concerning removing the employee again shall
be decided by a final medical determination. The employer need not
automatically remove such an employee pursuant to the blood lead level
removal criteria provided by this section.
(vii) Voluntary Removal or Restriction of An Employee. Where an
employer, although not required by this section to do so, removes an
employee from exposure to lead or otherwise places limitations on an
employee due to the effects of lead exposure on the employee's medical
condition, the employer shall provide medical removal protection
benefits to the employee equal to that required by paragraph (k)(2)(i)
of this section.
(l) Employee information and training--(1) Training program. (i)
Each employer who has a workplace in which there is a potential exposure
to airborne lead at any level shall inform employees of the content of
Appendices A and B of this regulation.
(ii) The employer shall train each employee who is subject to
exposure to lead at or above the action level, or for whom the
possibility of skin or eye irritation exists, in accordance with the
[[Page 112]]
requirements of this section. The employer shall institute a training
program and ensure employee participation in the program.
(iii) The employer shall provide initial training by 180 days from
the effective date for those employees covered by paragraph (l)(1) (ii)
on the standard's effective date and prior to the time of initial job
assignment for those employees subsequently covered by this paragraph.
(iv) The training program shall be repeated at least annually for
each employee.
(v) The employer shall assure that each employee is informed of the
following:
(A) The content of this standard and its appendices;
(B) The specific nature of the operations which could result in
exposure to lead above the action level;
(C) The purpose, proper selection, fitting, use, and limitations of
respirators;
(D) The purpose and a description of the medical surveillance
program, and the medical removal protection program including
information concerning the adverse health effects associated with
excessive exposure to lead (with particular attention to the adverse
reproductive effects on both males and females);
(E) The engineering controls and work practices associated with the
employee's job assignment;
(F) The contents of any compliance plan in effect; and
(G) Instructions to employees that chelating agents should not
routinely be used to remove lead from their bodies and should not be
used at all except under the direction of a licensed physician;
(2) Access to information and training materials. (i) The employer
shall make readily available to all affected employees a copy of this
standard and its appendices.
(ii) The employer shall provide, upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(iii) In addition to the information required by paragraph
(l)(1)(v), the employer shall include as part of the training program,
and shall distribute to employees, any materials pertaining to the
Occupational Safety and Health Act, the regulations issued pursuant to
that Act, and this lead standard, which are made available to the
employer by the Assistant Secretary.
(m) Communication of hazards--(1) Hazard communication--general. (i)
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard Communication Standard (HCS)
(Sec. 1910.1200) for lead.
(ii) In classifying the hazards of lead at least the following
hazards are to be addressed: Reproductive/developmental toxicity;
central nervous system effects; kidney effects; blood effects; and acute
toxicity effects.
(iii) Employers shall include lead in the hazard communication
program established to comply with the HCS (Sec. 1910.1200). Employers
shall ensure that each employee has access to labels on containers of
lead and to safety data sheets, and is trained in accordance with the
requirements of HCS and paragraph (l) of this section.
(2) Signs. (i) The employer shall post the following warning signs
in each work area where the PEL is exceeded:
DANGER
LEAD
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
(ii) The employer shall ensure that no statement appears on or near
any sign required by this paragraph (m)(2) which contradicts or detracts
from the meaning of the required sign.
(iii) The employer shall ensure that signs required by this
paragraph (m)(2) are illuminated and cleaned as necessary so that the
legend is readily visible.
(iv) The employer may use signs required by other statutes,
regulations, or ordinances in addition to, or in combination with, signs
required by this paragraph (m)(2).
(v) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (m)(2)(ii) of this section:
[[Page 113]]
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
(n) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and maintain an accurate record of all monitoring required in
paragraph (d) of this section.
(ii) This record shall include:
(A) The date(s), number, duration, location and results of each of
the samples taken, including a description of the sampling procedure
used to determine representative employee exposure where applicable;
(B) A description of the sampling and analytical methods used and
evidence of their accuracy;
(C) The type of respiratory protective devices worn, if any;
(D) Name, social security number, and job classification of the
employee monitored and of all other employees whose exposure the
measurement is intended to represent; and
(E) The environmental variables that could affect the measurement of
employee exposure.
(iii) The employer shall maintain these monitoring records for at
least 40 years or for the duration of employment plus 20 years,
whichever is longer.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (j) of this section.
(ii) This record shall include:
(A) The name, social security number, and description of the duties
of the employee;
(B) A copy of the physician's written opinions;
(C) Results of any airborne exposure monitoring done for that
employee and the representative exposure levels supplied to the
physician; and
(D) Any employee medical complaints related to exposure to lead.
(iii) The employer shall keep, or assure that the examining
physician keeps, the following medical records:
(A) A copy of the medical examination results including medical and
work history required under paragraph (j) of this section;
(B) A description of the laboratory procedures and a copy of any
standards or guidelines used to interpret the test results or references
to that information;
(C) A copy of the results of biological monitoring.
(iv) The employer shall maintain or assure that the physician
maintains those medical records for at least 40 years, or for the
duration of employment plus 20 years, whichever is longer.
(3) Medical removals. (i) The employer shall establish and maintain
an accurate record for each employee removed from current exposure to
lead pursuant to paragraph (k) of this section.
(ii) Each record shall include:
(A) The name and social security number of the employee;
(B) The date on each occasion that the employee was removed from
current exposure to lead as well as the corresponding date on which the
employee was returned to his or her former job status;
(C) A brief explanation of how each removal was or is being
accomplished; and
(D) A statement with respect to each removal indicating whether or
not the reason for the removal was an elevated blood lead level.
(iii) The employer shall maintain each medical removal record for at
least the duration of an employee's employment.
(4) Availability. (i) The employer shall make available upon request
all records required to be maintained by paragraph (n) of this section
to the Assistant Secretary and the Director for examination and copying.
(ii) Environmental monitoring, medical removal, and medical records
required by this paragraph shall be provided upon request to employees,
designated representatives, and the Assistant Secretary in accordance
with 29 CFR 1910.1020 (a)-(e) and (2)-(i). Medical removal records shall
be provided in the same manner as environmental monitoring records.
(5) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by paragraph (n) of this section.
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(ii) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.1020(h).
(o) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to lead conducted pursuant to paragraph (d) of this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to lead requires entry into an area
where the use of respirators, protective clothing or equipment is
required, the employer shall provide the observer with and assure the
use of such respirators, clothing and such equipment, and shall require
the observer to comply with all other applicable safety and health
procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled to:
(A) Receive an explanation of the measurement procedures;
(B) Observe all steps related to the monitoring of lead performed at
the place of exposure; and
(C) Record the results obtained or receive copies of the results
when returned by the laboratory.
(p) Appendices. The information contained in the appendices to this
section is not intended by itself, to create any additional obligations
not otherwise imposed by this standard nor detract from any existing
obligation.
Appendix A toSec. 1910.1025--Substance Data Sheet for Occupational
Exposure to Lead
i. Substance Identification
A. Substance: Pure lead (Pb) is a heavy metal at room temperature
and pressure and is a basic chemical element. It can combine with
various other substances to form numerous lead compounds.
B. Compounds Covered by the Standard: The word ``lead'' when used in
this standard means elemental lead, all inorganic lead compounds and a
class of organic lead compounds called lead soaps. This standard does
not apply to other organic lead compounds.
C. Uses: Exposure to lead occurs in at least 120 different
occupations, including primary and secondary lead smelting, lead storage
battery manufacturing, lead pigment manufacturing and use, solder
manufacturing and use, shipbuilding and ship repairing, auto
manufacturing, and printing.
D. Permissible Exposure: The Permissible Exposure Limit (PEL) set by
the standard is 50 micrograms of lead per cubic meter of air (50
[micro]g/m\3\), averaged over an 8-hour workday.
E. Action Level: The standard establishes an action level of 30
micrograms per cubic meter of air (30 [micro]g/m\3\), time weighted
average, based on an 8-hour work-day. The action level initiates several
requirements of the standard, such as exposure monitoring, medical
surveillance, and training and education.
ii. health hazard data
A. Ways in which lead enters your body. When absorbed into your body
in certain doses lead is a toxic substance. The object of the lead
standard is to prevent absorption of harmful quantities of lead. The
standard is intended to protect you not only from the immediate toxic
effects of lead, but also from the serious toxic effects that may not
become apparent until years of exposure have passed.
Lead can be absorbed into your body by inhalation (breathing) and
ingestion (eating). Lead (except for certain organic lead compounds not
covered by the standard, such as tetraethyl lead) is not absorbed
through your skin. When lead is scattered in the air as a dust, fume or
mist it can be inhaled and absorbed through you lungs and upper
respiratory tract. Inhalation of airborne lead is generally the most
important source of occupational lead absorption. You can also absorb
lead through your digestive system if lead gets into your mouth and is
swallowed. If you handle food, cigarettes, chewing tobacco, or make-up
which have lead on them or handle them with hands contaminated with
lead, this will contribute to ingestion.
A significant portion of the lead that you inhale or ingest gets
into your blood stream. Once in your blood stream, lead is circulated
throughout your body and stored in various organs and body tissues. Some
of this lead is quickly filtered out of your body and excreted, but some
remains in the blood and other tissues. As exposure to lead continues,
the amount stored in your body will increase if you are absorbing more
lead than your body is excreting. Even though you may not be aware of
any immediate symptoms of disease, this lead stored in your tissues can
be slowly causing irreversible damage, first to individual cells, then
to your organs and whole body systems.
B. Effects of overexposure to lead--(1) Short term (acute)
overexposure. Lead is a potent, systemic poison that serves no known
useful function once absorbed by your body. Taken in large enough doses,
lead can kill you in a matter of days. A condition affecting the brain
called acute encephalopathy may arise which develops quickly to
seizures, coma,
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and death from cardiorespiratory arrest. A short term dose of lead can
lead to acute encephalopathy. Short term occupational exposures of this
magnitude are highly unusual, but not impossible. Similar forms of
encephalopathy may, however, arise from extended, chronic exposure to
lower doses of lead. There is no sharp dividing line between rapidly
developing acute effects of lead, and chronic effects which take longer
to acquire. Lead adversely affects numerous body systems, and causes
forms of health impairment and disease which arise after periods of
exposure as short as days or as long as several years.
(2) Long-term (chronic) overexposure. Chronic overexposure to lead
may result in severe damage to your blood-forming, nervous, urinary and
reproductive systems. Some common symptoms of chronic overexposure
include loss of appetite, metallic taste in the mouth, anxiety,
constipation, nausea, pallor, excessive tiredness, weakness, insomnia,
headache, nervous irritability, muscle and joint pain or soreness, fine
tremors, numbness, dizziness, hyperactivity and colic. In lead colic
there may be severe abdominal pain.
Damage to the central nervous system in general and the brain
(encephalopathy) in particular is one of the most severe forms of lead
poisoning. The most severe, often fatal, form of encephalopathy may be
preceded by vomiting, a feeling of dullness progressing to drowsiness
and stupor, poor memory, restlessness, irritability, tremor, and
convulsions. It may arise suddenly with the onset of seizures, followed
by coma, and death. There is a tendency for muscular weakness to develop
at the same time. This weakness may progress to paralysis often observed
as a characteristic ``wrist drop'' or ``foot drop'' and is a
manifestation of a disease to the nervous system called peripheral
neuropathy.
Chronic overexposure to lead also results in kidney disease with
few, if any, symptoms appearing until extensive and most likely
permanent kidney damage has occurred. Routine laboratory tests reveal
the presence of this kidney disease only after about two-thirds of
kidney function is lost. When overt symptoms of urinary dysfunction
arise, it is often too late to correct or prevent worsening conditions,
and progression to kidney dialysis or death is possible.
Chronic overexposure to lead impairs the reproductive systems of
both men and women. Overexposure to lead may result in decreased sex
drive, impotence and sterility in men. Lead can alter the structure of
sperm cells raising the risk of birth defects. There is evidence of
miscarriage and stillbirth in women whose husbands were exposed to lead
or who were exposed to lead themselves. Lead exposure also may result in
decreased fertility, and abnormal menstrual cycles in women. The course
of pregnancy may be adversely affected by exposure to lead since lead
crosses the placental barrier and poses risks to developing fetuses.
Children born of parents either one of whom were exposed to excess lead
levels are more likely to have birth defects, mental retardation,
behavioral disorders or die during the first year of childhood.
Overexposure to lead also disrupts the blood-forming system
resulting in decreased hemoglobin (the substance in the blood that
carries oxygen to the cells) and ultimately anemia. Anemia is
characterized by weakness, pallor and fatigability as a result of
decreased oxygen carrying capacity in the blood.
(3) Health protection goals of the standard. Prevention of adverse
health effects for most workers from exposure to lead throughout a
working lifetime requires that worker blood lead (PbB) levels be
maintained at or below forty micrograms per one hundred grams of whole
blood (40 [micro]g/100g). The blood lead levels of workers (both male
and female workers) who intend to have children should be maintained
below 30 [micro]g/100g to minimize adverse reproductive health effects
to the parents and to the developing fetus.
The measurement of your blood lead level is the most useful
indicator of the amount of lead being absorbed by your body. Blood lead
levels (PbB) are most often reported in units of milligrams (mg) or
micrograms ([micro]g) of lead (1 mg=1000 [micro]g) per 100 grams (100g),
100 milliters (100 ml) or deciliter (dl) of blood. These three units are
essentially the same. Sometime PbB's are expressed in the form of mg% or
[micro]g%. This is a shorthand notation for 100g, 100 ml, or dl.
PbB measurements show the amount of lead circulating in your blood
stream, but do not give any information about the amount of lead stored
in your various tissues. PbB measurements merely show current absorption
of lead, not the effect that lead is having on your body or the effects
that past lead exposure may have already caused. Past research into
lead-related diseases, however, has focused heavily on associations
between PbBs and various diseases. As a result, your PbB is an important
indicator of the likelihood that you will gradually acquire a lead-
related health impairment or disease.
Once your blood lead level climbs above 40 [micro]g/100g, your risk
of disease increases. There is a wide variability of individual response
to lead, thus it is difficult to say that a particular PbB in a given
person will cause a particular effect. Studies have associated fatal
encephalopathy with PbBs as low as 150 [micro]g/100g. Other studies have
shown other forms of diseases in some workers with PbBs well below 80
[micro]g/100g. Your PbB is a crucial indicator of the risks to your
health, but one other factor is also extremely important. This factor is
the length of time you have
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had elevated PbBs. The longer you have an elevated PbB, the greater the
risk that large quantities of lead are being gradually stored in your
organs and tissues (body burden). The greater your overall body burden,
the greater the chances of substantial permanent damage.
The best way to prevent all forms of lead-related impairments and
diseases--both short term and long term- is to maintain your PbB below
40 [micro]g/100g. The provisions of the standard are designed with this
end in mind. Your employer has prime responsibility to assure that the
provisions of the standard are complied with both by the company and by
individual workers. You as a worker, however, also have a responsibility
to assist your employer in complying with the standard. You can play a
key role in protecting your own health by learning about the lead
hazards and their control, learning what the standard requires,
following the standard where it governs your own actions, and seeing
that your employer complies with provisions governing his actions.
(4) Reporting signs and symptoms of health problems. You should
immediately notify your employer if you develop signs or symptoms
associated with lead poisoning or if you desire medical advice
concerning the effects of current or past exposure to lead on your
ability to have a healthy child. You should also notify your employer if
you have difficulty breathing during a respirator fit test or while
wearing a respirator. In each of these cases your employer must make
available to you appropriate medical examinations or consultations.
These must be provided at no cost to you and at a reasonable time and
place.
The standard contains a procedure whereby you can obtain a second
opinion by a physician of your choice if the employer selected the
initial physician.
Appendix B toSec. 1910.1025--Employee Standard Summary
This appendix summarizes key provisions of the standard that you as
a worker should become familiar with.
i. permissible exposure limit (pel)--paragraph (c)
The standards sets a permissible exposure limit (PEL) of fifty
micrograms of lead per cubic meter of air (50 [micro]g/m\3\), averaged
over an 8-hour work-day. This is the highest level of lead in air to
which you may be permissibly exposed over an 8-hour workday. Since it is
an 8-hour average it permits short exposures above the PEL so long as
for each 8-hour work day your average exposure does not exceed the PEL.
This standard recognizes that your daily exposure to lead can extend
beyond a typical 8-hour workday as the result of overtime or other
alterations in your work schedule. To deal with this, the standard
contains a formula which reduces your permissible exposure when you are
exposed more than 8 hours. For example, if you are exposed to lead for
10 hours a day, the maximum permitted average exposure would be 40
[micro]g/m\3\.
ii. exposure monitoring--paragraph (d)
If lead is present in the workplace where you work in any quantity,
your employer is required to make an initial determination of whether
the action level is exceeded for any employee. This initial
determination must include instrument monitoring of the air for the
presence of lead and must cover the exposure of a representative number
of employees who are reasonably believed to have the highest exposure
levels. If your employer has conducted appropriate air sampling for lead
in the past year he may use these results. If there have been any
employee complaints of symptoms which may be attributable to exposure to
lead or if there is any other information or observations which would
indicate employee exposure to lead, this must also be considered as part
of the initial determination. This initial determination must have been
completed by March 31, 1979. If this initial determination shows that a
reasonable possibility exists that any employee may be exposed, without
regard to respirators, over the action level (30 [micro]g/m\3\) your
employer must set up an air monitoring program to determine the exposure
level of every employee exposed to lead at your workplace.
In carrying out this air monitoring program, your employer is not
required to monitor the exposure of every employee, but he must monitor
a representative number of employees and job types. Enough sampling must
be done to enable each employee's exposure level to be reasonably least
one full shift (at least 7 hours) air sample. In addition, these air
samples must be taken under conditions which represent each employee's
regular, daily exposure to lead. All initial exposure monitoring must
have been completed by May 30, 1979.
If you are exposed to lead and air sampling is performed, your
employer is required to quickly notify you in writing of air monitoring
results which represent your exposure. If the results indicate your
exposure exceeds the PEL (without regard to your use of respirators),
then your employer must also notify you of this in writing, and provide
you with a description of the corrective action that will be taken to
reduce your exposure.
Your exposure must be rechecked by monitoring every six months if
your exposure is over the action level but below the PEL. Air monitoring
must be repeated every 3 months if you are exposed over the PEL. Your
employer may discontinue monitoring for you if
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2 consecutive measurements, taken at least two weeks apart, are below
the action level. However, whenever there is a production, process,
control, or personnel change at your workplace which may result in new
or additional exposure to lead, or whenever there is any other reason to
suspect a change which may result in new or additional exposure to lead,
your employer must perform additional monitoring.
iii. methods of compliance--paragraph (e)
Your employer is required to assure that no employee is exposed to
lead in excess of the PEL. The standard establishes a priority of
methods to be used to meet the PEL.
iv. respiratory protection--paragraph (f)
Your employer is required to provide and assure your use of
respirators when your exposure to lead is not controlled below the PEL
by other means. The employer must pay the cost of the respirator.
Whenever you request one, your employer is also required to provide you
a respirator even if your air exposure level does not exceed the PEL.
You might desire a respirator when, for example, you have received
medical advice that your lead absorption should be decreased. Or, you
may intend to have children in the near future, and want to reduce the
level of lead in your body to minimize adverse reproductive effects.
While respirators are the least satisfactory means of controlling your
exposure, they are capable of providing significant protection if
properly chosen, fitted, worn, cleaned, maintained, and replaced when
they stop providing adequate protection.
Your employer is required to select respirators from the seven types
listed in Table II of the Respiratory Protection section of the standard
(Sec. 1910.1025(f)). Any respirator chosen must be approved by the
National Institute for Occupational Safety and Health (NIOSH) under the
provisions of 42 CFR part 84. This respirator selection table will
enable your employer to choose a type of respirator that will give you a
proper amount of protection based on your airborne lead exposure. Your
employer may select a type of respirator that provides greater
protection than that required by the standard; that is, one recommended
for a higher concentration of lead than is present in your workplace.
For example, a powered air-purifying respirator (PAPR) is much more
protective than a typical negative pressure respirator, and may also be
more comfortable to wear. A PAPR has a filter, cartridge, or canister to
clean the air, and a power source that continuously blows filtered air
into your breathing zone. Your employer might make a PAPR available to
you to ease the burden of having to wear a respirator for long periods
of time. The standard provides that you can obtain a PAPR upon request.
Your employer must also start a Respiratory Protection Program. This
program must include written procedures for the proper selection, use,
cleaning, storage, and maintenance of respirators.
Your employer must ensure that your respirator facepiece fits
properly. Proper fit of a respirator facepiece is critical to your
protection from airborne lead. Obtaining a proper fit on each employee
may require your employer to make available several different types of
respirator masks. To ensure that your respirator fits properly and that
facepiece leakage is minimal, your employer must give you either a
qualitative or quantitative fit test as specified in appendix A of the
Respiratory Protection standard located at 29 CFR 1910.134.
You must also receive from your employer proper training in the use
of respirators. Your employer is required to teach you how to wear a
respirator, to know why it is needed, and to understand its limitations.
The standard provides that if your respirator uses filter elements,
you must be given an opportunity to change the filter elements whenever
an increase in breathing resistance is detected. You also must be
permitted to periodically leave your work area to wash your face and
respirator facepiece whenever necessary to prevent skin irritation. If
you ever have difficulty in breathing during a fit test or while using a
respirator, your employer must make a medical examination available to
you to determine whether you can safely wear a respirator. The result of
this examination may be to give you a positive pressure respirator
(which reduces breathing resistance) or to provide alternative means of
protection.
v. protective work clothing and equipment--paragraph (g)
If you are exposed to lead above the PEL, or if you are exposed to
lead compounds such as lead arsenate or lead azide which can cause skin
and eye irritation, your employer must provide you with protective work
clothing and equipment appropriate for the hazard. If work clothing is
provided, it must be provided in a clean and dry condition at least
weekly, and daily if your airborne exposure to lead is greater than 200
[micro]g/m\3\. Appropriate protective work clothing and equipment can
include coveralls or similar full-body work clothing, gloves, hats,
shoes or disposable shoe coverlets, and face shields or vented goggles.
Your employer is required to provide all such equipment at no cost to
you. He is responsible for providing repairs and replacement as
necessary, and also is responsible for the cleaning, laundering or
disposal of protective clothing and equipment. Contaminated work
clothing or equipment must be removed in change rooms and not worn home
or you will extend your exposure and expose your family since lead from
your
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clothing can accumulate in your house, car, etc. Contaminated clothing
which is to be cleaned, laundered or disposed of must be placed in
closed containers in the change room. At no time may lead be removed
from protective clothing or equipment by any means which disperses lead
into the workroom air.
vi. housekeeping--paragraph (h)
Your employer must establish a housekeeping program sufficient to
maintain all surfaces as free as practicable of accumulations of lead
dust. Vacuuming is the preferred method of meeting this requirement, and
the use of compressed air to clean floors and other surfaces is
absolutely prohibited. Dry or wet sweeping, shoveling, or brushing may
not be used except where vaccuming or other equally effective methods
have been tried and do not work. Vacuums must be used and emptied in a
manner which minimizes the reentry of lead into the workplace.
vii. hygiene facilities and practices--paragraph (i)
The standard requires that change rooms, showers, and filtered air
lunchrooms be constructed and made available to workers exposed to lead
above the PEL. When the PEL is exceeded the employer must assure that
food and beverage is not present or consumed, tobacco products are not
present or used, and cosmetics are not applied, except in these
facilities. Change rooms, showers, and lunchrooms, must be used by
workers exposed in excess of the PEL. After showering, no clothing or
equipment worn during the shift may be worn home, and this includes
shoes and underwear. Your own clothing worn during the shift should be
carried home and cleaned carefully so that it does not contaminate your
home. Lunchrooms may not be entered with protective clothing or
equipment unless surface dust has been removed by vacuuming, downdraft
booth, or other cleaning method. Finally, workers exposed above the PEL
must wash both their hands and faces prior to eating, drinking, smoking
or applying cosmetics.
All of the facilities and hygiene practices just discussed are
essential to minimize additional sources of lead absorption from
inhalation or ingestion of lead that may accumulate on you, your
clothes, or your possessions. Strict compliance with these provisions
can virtually eliminate several sources of lead exposure which
significantly contribute to excessive lead absorption.
viii. medical surveillance--paragraph (j)
The medical surveillance program is part of the standard's
comprehensive approach to the prevention of lead-related disease. Its
purpose is to supplement the main thrust of the standard which is aimed
at minimizing airborne concentrations of lead and sources of ingestion.
Only medical surveillance can determine if the other provisions of the
standard have affectively protected you as an individual. Compliance
with the standard's provision will protect most workers from the adverse
effects of lead exposure, but may not be satisfactory to protect
individual workers (1) who have high body burdens of lead acquired over
past years, (2) who have additional uncontrolled sources of non-
occupational lead exposure, (3) who exhibit unusual variations in lead
absorption rates, or (4) who have specific non-work related medical
conditions which could be aggravated by lead exposure (e.g., renal
disease, anemia). In addition, control systems may fail, or hygiene and
respirator programs may be inadequate. Periodic medical surveillance of
individual workers will help detect those failures. Medical surveillance
will also be important to protect your reproductive ability--regardless
of whether you are a man or woman.
All medical surveillance required by the standard must be performed
by or under the supervision of a licensed physician. The employer must
provide required medical surveillance without cost to employees and at a
reasonable time and place. The standard's medical surveillance program
has two parts-periodic biological monitoring and medical examinations.
Your employer's obligation to offer you medical surveillance is
triggered by the results of the air monitoring program. Medical
surveillance must be made available to all employees who are exposed in
excess of the action level for more than 30 days a year. The initial
phase of the medical surveillance program, which includes blood lead
level tests and medical examinations, must be completed for all covered
employees no later than August 28, 1979. Priority within this first
round of medical surveillance must be given to employees whom the
employer believes to be at greatest risk from continued exposure (for
example, those with the longest prior exposure to lead, or those with
the highest current exposure). Thereafter, the employer must
periodically make medical surveillance--both biological monitoring and
medical examinations--available to all covered employees.
Biological monitoring under the standard consists of blood lead
level (PbB) and zinc protoporphyrin tests at least every 6 months after
the initial PbB test. A zinc protoporphyrin (ZPP) test is a very useful
blood test which measures an effect of lead on your body. Thus
biological monitoring under the standard is currently limited to PbB
testing. If a worker's PbB exceeds 40 [micro]g/100g the monitoring
frequency must be increased from every 6 months to at least every 2
months and not reduced until two consecutive PbBs indicate a blood lead
level
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below 40 [micro]g/100g. Each time your PbB is determined to be over 40
[micro]g/100g, your employer must notify you of this in writing within
five working days of his receipt of the test results. The employer must
also inform you that the standard requires temporary medical removal
with economic protection when your PbB exceeds certain criteria. (See
Discussion of Medical Removal Protection--Paragraph (k).) During the
first year of the standard, this removal criterion is 80 [micro]g/100g.
Anytime your PbB exceeds 80 [micro]g/100g your employer must make
available to you a prompt follow-up PbB test to ascertain your PbB. If
the two tests both exceed 80 [micro]g/100g and you are temporarily
removed, then your employer must make successive PbB tests available to
you on a monthly basis during the period of your removal.
Medical examinations beyond the initial one must be made available
on an annual basis if your blood lead level exceeds 40 [micro]g/100g at
any time during the preceding year. The initial examination will provide
information to establish a baseline to which subsequent data can be
compared. An initial medical examination must also be made available
(prior to assignment) for each employee being assigned for the first
time to an area where the airborne concentration of lead equals or
exceeds the action level. In addition, a medical examination or
consultation must be made available as soon as possible if you notify
your employer that you are experiencing signs or symptoms commonly
associated with lead poisoning or that you have difficulty breathing
while wearing a respirator or during a respirator fit test. You must
also be provided a medical examination or consultation if you notify
your employer that you desire medical advice concerning the effects of
current or past exposure to lead on your ability to procreate a healthy
child.
Finally, appropriate follow-up medical examinations or consultations
may also be provided for employees who have been temporarily removed
from exposure under the medical removal protection provisions of the
standard. (See part IX, below.)
The standard specifies the minimum content of pre-assignment and
annual medical examinations. The content of other types of medical
examinations and consultations is left up to the sound discretion of the
examining physician. Pre-assignment and annual medical examinations must
include (1) a detailed work history and medical history, (2) a thorough
physical examination, and (3) a series of laboratory tests designed to
check your blood chemistry and your kidney function. In addition, at any
time upon your request, a laboratory evaluation of male fertility will
be made (microscopic examination of a sperm sample), or a pregnancy test
will be given.
The standard does not require that you participate in any of the
medical procedures, tests, etc. which your employer is required to make
available to you. Medical surveillance can, however, play a very
important role in protecting your health. You are strongly encouraged,
therefore, to participate in a meaningful fashion. The standard contains
a multiple physician review mechanism which would give you a chance to
have a physician of your choice directly participate in the medical
surveillance program. If you were dissatisfied with an examination by a
physician chosen by your employer, you could select a second physician
to conduct an independent analysis. The two doctors would attempt to
resolve any differences of opinion, and select a third physician to
resolve any firm dispute. Generally your employer will choose the
physician who conducts medical surveillance under the lead standard--
unless you and your employer can agree on the choice of a physician or
physicians. Some companies and unions have agreed in advance, for
example, to use certain independent medical laboratories or panels of
physicians. Any of these arrangements are acceptable so long as required
medical surveillance is made available to workers.
The standard requires your employer to provide certain information
to a physician to aid in his or her examination of you. This information
includes (1) the standard and its appendices, (2) a description of your
duties as they relate to lead exposure, (3) your exposure level, (4) a
description of personal protective equipment you wear, (5) prior blood
lead level results, and (6) prior written medical opinions concerning
you that the employer has. After a medical examination or consultation
the physician must prepare a written report which must contain (1) the
physician's opinion as to whether you have any medical condition which
places you at increased risk of material impairment to health from
exposure to lead, (2) any recommended special protective measures to be
provided to you, (3) any blood lead level determinations, and (4) any
recommended limitation on your use of respirators. This last element
must include a determination of whether you can wear a powered air
purifying respirator (PAPR) if you are found unable to wear a negative
pressure respirator.
The medical surveillance program of the lead standard may at some
point in time serve to notify certain workers that they have acquired a
disease or other adverse medical condition as a result of occupational
lead exposure. If this is true, these workers might have legal rights to
compensation from public agencies, their employers, firms that supply
hazardous products to their employers, or other persons. Some states
have laws, including worker compensation laws, that disallow a worker
who learns of a job-
[[Page 120]]
related health impairment to sue, unless the worker sues within a short
period of time after learning of the impairment. (This period of time
may be a matter of months or years.) An attorney can be consulted about
these possibilities. It should be stressed that OSHA is in no way trying
to either encourage or discourage claims or lawsuits. However, since
results of the standard's medical surveillance program can significantly
affect the legal remedies of a worker who has acquired a job-related
disease or impairment, it is proper for OSHA to make you aware of this.
The medical surveillance section of the standard also contains
provisions dealing with chelation. Chelation is the use of certain drugs
(administered in pill form or injected into the body) to reduce the
amount of lead absorbed in body tissues. Experience accumulated by the
medical and scientific communities has largely confirmed the
effectiveness of this type of therapy for the treatment of very severe
lead poisoning. On the other hand, it has also been established that
there can be a long list of extremely harmful side effects associated
with the use of chelating agents. The medical community has balanced the
advantages and disadvantages resulting from the use of chelating agents
in various circumstances and has established when the use of these
agents is acceptable. The standard includes these accepted limitations
due to a history of abuse of chelation therapy by some lead companies.
The most widely used chelating agents are calcium disodium EDTA, (Ca
Na2 EDTA), Calcium Disodium Versenate (Versenate), and d-
penicillamine (pencillamine or Cupramine).
The standard prohibits ``prophylactic chelation'' of any employee by
any person the employer retains, supervises or controls. ``Prophylactic
chelation'' is the routine use of chelating or similarly acting drugs to
prevent elevated blood levels in workers who are occupationally exposed
to lead, or the use of these drugs to routinely lower blood lead levels
to predesignated concentrations believed to be `safe'. It should be
emphasized that where an employer takes a worker who has no symptoms of
lead poisoning and has chelation carried out by a physician (either
inside or outside of a hospital) solely to reduce the worker's blood
lead level, that will generally be considered prophylactic chelation.
The use of a hospital and a physician does not mean that prophylactic
chelation is not being performed. Routine chelation to prevent increased
or reduce current blood lead levels is unacceptable whatever the
setting.
The standard allows the use of ``therapeutic'' or ``diagnostic''
chelation if administered under the supervision of a licensed physician
in a clinical setting with thorough and appropriate medical monitoring.
Therapeutic chelation responds to severe lead poisoning where there are
marked symptoms. Diagnostic chelation involved giving a patient a dose
of the drug then collecting all urine excreted for some period of time
as an aid to the diagnosis of lead poisoning.
In cases where the examining physician determines that chelation is
appropriate, you must be notified in writing of this fact before such
treatment. This will inform you of a potentially harmful treatment, and
allow you to obtain a second opinion.
ix. medical removal protection--paragraph (k)
Excessive lead absorption subjects you to increased risk of disease.
Medical removal protection (MRP) is a means of protecting you when, for
whatever reasons, other methods, such as engineering controls, work
practices, and respirators, have failed to provide the protection you
need. MRP involves the temproary removal of a worker from his or her
regular job to a place of significantly lower exposure without any loss
of earnings, seniority, or other employment rights or benefits. The
purpose of this program is to cease further lead absorption and allow
your body to naturally excrete lead which has previously been absorbed.
Temporary medical removal can result from an elevated blood lead level,
or a medical opinion. Up to 18 months of protection is provided as a
result of either form of removal. The vast majority of removed workers,
however, will return to their former jobs long before this eighteen
month period expires. The standard contains special provisions to deal
with the extraordinary but possible case where a longterm worker's blood
lead level does not adequately decline during eighteen months of
removal.
During the first year of the standard, if your blood lead level is
80 [micro]g/100g or above you must be removed from any exposure where
your air lead level without a respirator would be 100 [micro]g/m\3\ or
above. If you are removed from your normal job you may not be returned
until your blood lead level declines to at least 60 [micro]g/100g. These
criteria for removal and return will change according to the following
schedule:
----------------------------------------------------------------------------------------------------------------
Removal blood lead Air lead ([micro]g/ Return blood lead
([micro]g/100 g) m\3\) ([micro]g/100 g)
----------------------------------------------------------------------------------------------------------------
After Mar. 1, 1980................... 70 and above........... 50 and above........... At or below 50.
After Mar. 1, 1981................... 60 and above........... 30 and above........... At or below 40.
[[Page 121]]
After Mar. 1, 1983................... 50 and above averaged 30 and above........... Do.
over six months.
----------------------------------------------------------------------------------------------------------------
You may also be removed from exposure even if your blood lead levels
are below these criteria if a final medical determination indicates that
you temporarily need reduced lead exposure for medical reasons. If the
physician who is implementing your employers medical program makes a
final written opinion recommending your removal or other special
protective measures, your employer must implement the physician's
recommendation. If you are removed in this manner, you may only be
returned when the doctor indicates that it is safe for you to do so.
The standard does not give specific instructions dealing with what
an employer must do with a removed worker. Your job assignment upon
removal is a matter for you, your employer and your union (if any) to
work out consistent with existing procedures for job assignments. Each
removal must be accomplished in a manner consistent with existing
collective bargaining relationships. Your employer is given broad
discretion to implement temporary removals so long as no attempt is made
to override existing agreements. Similarly, a removed worker is provided
no right to veto an employer's choice which satisfies the standard.
In most cases, employers will likely transfer removed employees to
other jobs with sufficiently low lead exposure. Alternatively, a
worker's hours may be reduced so that the time weighted average exposure
is reduced, or he or she may be temporarily laid off if no other
alternative is feasible.
In all of these situation, MRP benefits must be provided during the
period of removal--i.e., you continue to receive the same earnings,
seniority, and other rights and benefits you would have had if you had
not been removed. Earnings includes more than just your base wage; it
includes overtime, shift differentials, incentives, and other
compensation you would have earned if you had not been removed. During
the period of removal you must also be provided with appropriate follow-
up medical surveillance. If you were removed because your blood lead
level was too high, you must be provided with a monthly blood test. If a
medical opinion caused your removal, you must be provided medical tests
or examinations that the doctor believes to be appropriate. If you do
not participate in this follow up medical surveillance, you may lose
your eligibility for MRP benefits.
When you are medically eligible to return to your former job, your
employer must return you to your ``former job status.'' This means that
you are entitled to the position, wages, benefits, etc., you would have
had if you had not been removed. If you would still be in your old job
if no removal had occurred that is where you go back. If not, you are
returned consistent with whatever job assignment discretion your
employer would have had if no removal had occurred. MRP only seeks to
maintain your rights, not expand them or diminish them.
If you are removed under MRP and you are also eligible for worker
compensation or other compensation for lost wages, your employer's MRP
benefits obligation is reduced by the amount that you actually receive
from these other sources. This is also true if you obtain other
employment during the time you are laid off with MRP benefits.
The standard also covers situations where an employer voluntarily
removes a worker from exposure to lead due to the effects of lead on the
employee's medical condition, even though the standard does not require
removal. In these situations MRP benefits must still be provided as
though the standard required removal. Finally, it is important to note
that in all cases where removal is required, respirators cannot be used
as a substitute. Respirators may be used before removal becomes
necessary, but not as an alternative to a transfer to a low exposure
job, or to a lay-off with MRP benefits.
x. employee information and training--paragraph (l)
Your employer is required to provide an information and training
program for all employees exposed to lead above the action level or who
may suffer skin or eye irritation from lead. This program must inform
these employees of the specific hazards associated with their work
environment, protective measures which can be taken, the danger of lead
to their bodies (including their reproductive systems), and their rights
under the standard. In addition your employer must make readily
available to all employees, including those exposed below the action
level, a copy of the standard and its appendices and must distribute to
all employees any materials provided to the employer by the Occupational
Safety and Health Administration (OSHA).
Your employer is required to complete this training program for all
employees by August 28, 1979. After this date, all new employees must be
trained prior to initial assignment to areas where there is a
possibility of exposure over the action level.
[[Page 122]]
This training program must also be provided at least annually
thereafter.
xi. SIGNS--PARAGRAPH (m)
The standard requires that the following warning sign be posted in
the work areas when the exposure to lead exceeds the PEL:
DANGER
LEAD
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
However, prior to June 1, 2016, employers may use the following
legend in lieu of that specified above:
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
xii. recordkeeping--paragraph (n)
Your employer is required to keep all records of exposure monitoring
for airborne lead. These records must include the name and job
classification of employees measured, details of the sampling and
analytic techniques, the results of this sampling, and the type of
respiratory protection being worn by the person sampled. Your employer
is also required to keep all records of biological monitoring and
medical examination results. These must include the names of the
employees, the physician's written opinion, and a copy of the results of
the examination. All of the above kinds of records must be kept for 40
years, or for at least 20 years after your termination of employment,
whichever is longer.
Recordkeeping is also required if you are temporarily removed from
your job under the medical removal protection program. This record must
include your name and social security number, the date of your removal
and return, how the removal was or is being accomplished, and whether or
not the reason for the removal was an elevated blood lead level. Your
employer is required to keep each medical removal record only for as
long as the duration of an employee's employment.
The standard requires that if you request to see or copy
environmental monitoring, blood lead level monitoring, or medical
removal records, they must be made available to you or to a
representative that you authorize. Your union also has access to these
records. Medical records other than PbB's must also be provided upon
request to you, to your physician or to any other person whom you may
specifically designate. Your union does not have access to your personal
medical records unless you authorize their access.
xiii. observations of monitoring--paragraph (o)
When air monitoring for lead is performed at your workplace as
required by this standard, your employer must allow you or someone you
designate to act as an observer of the monitoring. Observers are
entitled to an explanation of the measurement procedure, and to record
the results obtained. Since results will not normally be available at
the time of the monitoring, observers are entitled to record or receive
the results of the monitoring when returned by the laboratory. Your
employer is required to provide the observer with any personal
protective devices required to be worn by employees working in the area
that is being monitored. The employer must require the observer to wear
all such equipment and to comply with all other applicable safety and
health procedures.
xiv. for additional information
A. Copies of the Standard and explanatory material may be obtained
by writing or calling the OSHA Docket Office, U.S. Department of Labor,
room N2634, 200 Constitution Avenue, N.W., Washington, DC 20210.
Telephone: (202) 219-7894.
1. The standard and summary of the statement of reasons (preamble),
Federal Register, Volume 43, pp. 52952-53014, November 14, 1978.
2. The full statement of reasons (preamble) Federal Register, vol.
43, pp. 54354-54509, November 21, 1978.
3. Partial Administrative Stay and Corrections to the standard, (44
FR 5446-5448) January 26, 1979.
4. Notice of the Partial Judicial Stay (44 FR 14554-14555) March 13,
1979.
5. Corrections to the preamble, Federal Register, vol. 44, pp.
20680-20681, April 6, 1979.
6. Additional correction to the preamble concerning the construction
industry, Federal Register, vol. 44, p. 50338, August 28, 1979.
7. Appendices to the standard (Appendices A, B, C), Federal
Register, Vol. 44, pp. 60980-60995, October 23, 1979.
8. Corrections to appendices, Federal Register, Vol. 44, 68828,
November 30, 1979.
9. Revision to the standard and an additional appendix (Appendix D),
Federal Register, Vol. 47, pp. 51117-51119, November 12, 1982.
10. Notice of reopening of lead rulemaking for nine remand industry
sectors, Federal Register, vol. 53, pp. 11511-11513, April 7, 1988.
11. Statement of reasons, Federal Register, vol. 54, pp. 29142-
29275, July 11, 1989.
[[Page 123]]
12. Statement of reasons, Federal Register, vol. 55, pp. 3146-3167,
January 30, 1990.
13. Correction to appendix B, Federal Register, vol. 55, pp. 4998-
4999, February 13, 1991.
14. Correction to appendices, Federal Register, vol. 56, p. 24686,
May 31, 1991.
B. Additional information about the standard, its enforcement, and
your employer's compliance can be obtained from the nearest OSHA Area
Office listed in your telephone directory under United States
Government/Department of Labor.
Appendix C toSec. 1910.1025--Medical Surveillance Guidelines
introduction
The primary purpose of the Occupational Safety and Health Act of
1970 is to assure, so far as possible, safe and healthful working
conditions for every working man and woman. The occupational health
standard for inorganic lead \1\ was promulgated to protect workers
exposed to inorganic lead including metallic lead, all inorganic lead
compounds and organic lead soaps.
---------------------------------------------------------------------------
\1\ The term inorganic lead used throughout the medical surveillance
appendices is meant to be synonymous with the definition of lead set
forth in the standard.
---------------------------------------------------------------------------
Under this final standard in effect as of March 1, 1979,
occupational exposure to inorganic lead is to be limited to 50 [micro]g/
m\3\ (micrograms per cubic meter) based on an 8 hour time-weighted
average (TWA). This level of exposure eventually must be achieved
through a combination of engineering, work practice and other
administrative controls. Periods of time ranging from 1 to 10 years are
provided for different industries to implement these controls. The
schedule which is based on individual industry considerations is given
in Table 1. Until these controls are in place, respirators must be used
to meet the 50 [micro]g/m\3\ exposure limit.
The standard also provides for a program of biological monitoring
and medical surveillance for all employees exposed to levels of
inorganic lead above the action level of 30 [micro]g/m\3\ (TWA) for more
than 30 days per year.
The purpose of this document is to outline the medical surveillance
provisions of the standard for inorganic lead, and to provide further
information to the physician regarding the examination and evaluation of
workers exposed to inorganic lead.
Section 1 provides a detailed description of the monitoring
procedure including the required frequency of blood testing for exposed
workers, provisions for medical removal protection (MRP), the
recommended right of the employee to a second medical opinion, and
notification and recordkeeping requirements of the employer. A
discussion of the requirements for respirator use and respirator
monitoring and OSHA's position on prophylactic chelation therapy are
also included in this section.
Section 2 discusses the toxic effects and clinical manifestations of
lead poisoning and effects of lead intoxication on enzymatic pathways in
heme synthesis. The adverse effects on both male and female reproductive
capacity and on the fetus are also discussed.
Section 3 outlines the recommended medical evaluation of the worker
exposed to inorganic lead including details of the medical history,
physical examination, and recommended laboratory tests, which are based
on the toxic effects of lead as discussed in Section 2.
Section 4 provides detailed information concerning the laboratory
tests available for the monitoring of exposed workers. Included also is
a discussion of the relative value of each test and the limitations and
precautions which are necessary in the interpretation of the laboratory
results.
Table 1
----------------------------------------------------------------------------------------------------------------
Effective date
-----------------------------------------------------------
Permissible airborne lead levels by industry Mar. 1,
([micro]g/m\3\) \1\ Mar. 1, Mar. 1, Mar. 1, Mar. 1, Mar. 1, 1989
1979 1980 1981 1982 1984 (final)
----------------------------------------------------------------------------------------------------------------
1. Primary lead production.......................... 200 200 200 100 100 50
2. Secondary lead production........................ 200 200 200 100 50 50
3. Lead-acid battery manufacturing.................. 200 200 100 100 50 50
4. Nonferrous foundries............................. 200 100 100 100 50 50
5. Lead pigment manufacturing....................... 200 200 200 100 50 50
6. All other industries............................. 200 50 50 50 50 50
----------------------------------------------------------------------------------------------------------------
\1\ Airborne levels to be achieved without reliance or respirator protection through a combination of
engineering, work practice and other administrative controls. While these controls are being implemented
respirators must be used to meet the 50 [micro]g/m\3\ exposure limit.
[[Page 124]]
i. medical surveillance and monitoring requirements for workers exposed
to inorganic lead
Under the occupational health standard for inorganic lead, a program
of biological monitoring and medical surveillance is to be made
available to all employees exposed to lead above the action level of 30
[micro]g/m\3\ TWA for more than 30 days each year. This program consists
of periodic blood sampling and medical evaluation to be performed on a
schedule which is defined by previous laboratory results, worker
complaints or concerns, and the clinical assessment of the examining
physician.
Under this program, the blood lead level of all employees who are
exposed to lead above the action level of 30 [micro]g/m\3\ is to be
determined at least every six months. The frequency is increased to
every two months for employees whose last blood lead level was between
40 [micro]g/100 g whole blood and the level requiring employee medical
removal to be discussed below. For employees who are removed from
exposure to lead due to an elevated blood lead, a new blood lead level
must be measured monthly. A zinc protoporphyrin (ZPP) is required on
each occasion that a blood lead level measurement is made.
An annual medical examination and consultation performed under the
guidelines discussed in Section 3 is to be made available to each
employee for whom a blood test conducted at any time during the
preceding 12 months indicated a blood lead level at or above 40
[micro]g/100 g. Also, an examination is to be given to all employees
prior to their assignment to an area in which airborne lead
concentrations reach or exceed the action level. In addition, a medical
examination must be provided as soon as possible after notification by
an employee that the employee has developed signs or symptoms commonly
associated with lead intoxication, that the employee desires medical
advice regarding lead exposure and the ability to procreate a healthy
child, or that the employee has demonstrated difficulty in breathing
during a respirator fitting test or during respirator use. An
examination is also to be made available to each employee removed from
exposure to lead due to a risk of sustaining material impairment to
health, or otherwise limited or specially protected pursuant to medical
recommendations.
Results of biological monitoring or the recommendations of an
examining physician may necessitate removal of an employee from further
lead exposure pursuant to the standard's medical removal protection
(MRP) program. The object of the MRP program is to provide temporary
medical removal to workers either with substantially elevated blood lead
levels or otherwise at risk of sustaining material health impairment
from continued substantial exposure to lead. The following guidelines
which are summarized in Table 2 were created under the standard for the
temporary removal of an exposed employee and his or her subsequent
return to work in an exposure area.
Table 2
----------------------------------------------------------------------------------------------------------------
Effective date
--------------------------------------------------------------------------------
Mar. 1, 1983
Mar. 1, 1979 Mar. 1, 1980 Mar. 1, 1981 Mar. 1, 1982 (final)
----------------------------------------------------------------------------------------------------------------
A. Blood lead level requiring =80 =70 =6 =6 =60[mi
employee medical removal. [micro]g/100 [micro]g/100 0 [micro]g/ 0 [micro]g/ cro]g/100 g or
(Level must be confirmed with g g 100 g 100 g average of last
second follow-up blood lead three blood
level within two weeks of samples or all
first report.). blood samples
over previous 6
months
(whichever is
over a longer
time period) is
50 [micro]g/100
g or greater
unless last
blood sample is
40 [micro]g/100
g or less.
B. Frequency which employees
exposed to action level of
lead (30 [micro]g/m\3\ TWA)
must have blood lead level
checked (ZPP is also required
in each occasion that a blood
lead is obtained.):
1. Last blood lead level less Every 6 months Every 6 months Every 6 Every 6 Every 6 months.
than 40 [micro]g/100 g. months months
2. Last blood lead level Every 2 months Every 2 months Every 2 Every 2 Every 2 months.
between 40 [micro]g/100 g months months
and level requiring medical
removal (see A above).
3. Employees removed from Every 1 month Every 1 month Every 1 month Every 1 month Every 1 month.
exposure to lead because of
an elevated blood lead level.
[[Page 125]]
C. Permissible airborne 100 [micro]g/ 50 [micro]g/ 30 [micro]g/ 30 [micro]g/ 30 [micro]g/m\3\
exposure limit for workers m\3\ 8 hr TWA m\3\ 8 hr TWA m\3\ 8 hr m\3\ 8 hr 8 hr TWA.
removed from work due to an TWA TWA
elevated blood lead level
(without regard to respirator
protection).
D. Blood lead level confirmed [middot]60 [middot]50 [middot]40 [middot]40 [middot]40
with a second blood analysis, [micro]g/100 [micro]g/100 [micro]g/100 [micro]g/100 [micro]g/100 g.
at which employee may return g g g g
to work. Permissible exposure
without regard to respirator
protection is listed by
industry in Table I.
----------------------------------------------------------------------------------------------------------------
Note: When medical opinion indicates that an employee is at risk of material impairment from exposure to lead,
the physician can remove an employee from exposures exceeding the action level (or less) or recommend special
protective measures as deemed appropriate and necessary. Medical monitoring during the medical removal period
can be more stringent than noted in the table above if the physician so specifies. Return to work or removal
of limitations and special protections is permitted when the physician indicates that the worker is no longer
at risk of material impairment.
Under the standard's ultimate worker removal criteria, a worker is
to be removed from any work having any eight hour TWA exposure to lead
of 30 [micro]g/m\3\ or more whenever either of the following
circumstances apply: (1) a blood lead level of 60 [micro]g/100 g or
greater is obtained and confirmed by a second follow-up blood lead level
performed within two weeks after the employer receives the results of
the first blood sampling test, or (2) the average of the previous three
blood lead determinations or the average of all blood lead
determinations conducted during the previous six months, whichever
encompasses the longest time period, equals or exceeds 50 [micro]g/100
g, unless the last blood sample indicates a blood lead level at or below
40 [micro]g/100 g in which case the employee need not be removed.
Medical removal is to continue until two consecutive blood lead levels
are 40 [micro]g/100 g or less.
During the first two years that the ultimate removal criteria are
being phased in, the return criteria have been set to assure that a
worker's blood lead level has substantially declined during the period
of removal. From March 1, 1979 to March 1, 1980, the blood lead level
requiring employee medical removal is 80 [micro]g/100 g. Workers found
to have a confirmed blood lead at this level or greater need only be
removed from work having a daily 8 hour TWA exposure to lead at or above
100 [micro]g/m\3\. Workers so removed are to be returned to work when
their blood lead levels are at or below 60 [micro]g/100 g of whole
blood. From March 1, 1980 to March 1, 1981, the blood lead level
requiring medical removal is 70 [micro]g/100 g. During this period
workers need only be removed from jobs having a daily 8 hour TWA
exposure to lead at or above 50 [micro]g/m\3\ and are to be returned to
work when a level of 50 [micro]g/100 g is achieved. Beginning March 1,
1981, return depends on a worker's blood lead level declining to 40
[micro]g/100 g of whole blood.
As part of the standard, the employer is required to notify in
writing each employee whose blood lead level exceeds 40 [micro]g/100 g.
In addition each such employee is to be informed that the standard
requires medical removal with MRP benefits, discussed below, when an
employee's blood lead level exceeds the above defined limits.
In addition to the above blood lead level criteria, temporary worker
removal may also take place as a result of medical determinations and
recommendations. Written medical opinions must be prepared after each
examination pursuant to the standard. If the examining physician
includes a medical finding, determination or opinion that the employee
has a medical condition which places the employee at increased risk of
material health impairment from exposure to lead, then the employee must
be removed from exposure to lead at or above the action level.
Alternatively, if the examining physician recommends special protective
measures for an employee (e.g., use of a powered air purifying
respirator) or recommends limitations on an employee's exposure to lead,
then the employer must implement these recommendations. Recommendations
may be more stringent than the specific provisions of the standard. The
examining physician, therefore, is given broad flexibility to tailor
special protective procedures to the needs of individual employees. This
flexibility extends to the evaluation and management of pregnant workers
and male and female workers who are planning to raise children. Based on
the history, physical examination, and laboratory studies, the physician
might recommend special protective measures or medical removal for an
employee who is pregnant or who is planning to conceive a child
[[Page 126]]
when, in the physician's judgment, continued exposure to lead at the
current job would pose a significant risk. The return of the employee to
his or her former job status, or the removal of special protections or
limitations, depends upon the examining physician determining that the
employee is no longer at increased risk of material impairment or that
special measures are no longer needed.
During the period of any form of special protection or removal, the
employer must maintain the worker's earnings, seniority, and other
employment rights and benefits (as though the worker had not been
removed) for a period of up to 18 months. This economic protection will
maximize meaningful worker participation in the medical surveillance
program, and is appropriate as part of the employer's overall obligation
to provide a safe and healthful workplace. The provisions of MRP
benefits during the employee's removal period may, however, be
conditioned upon participation in medical surveillance.
On rare occasions, an employee's blood lead level may not acceptably
decline within 18 months of removal. This situation will arise only in
unusual circumstances, thus the standard relies on an individual medical
examination to determine how to protect such an employee. This medical
determination is to be based on both laboratory values, including lead
levels, zinc protoporphyrin levels, blood counts, and other tests felt
to be warranted, as well as the physician's judgment that any symptoms
or findings on physical examination are a result of lead toxicity. The
medical determination may be that the employee is incapable of ever
safely returning to his or her former job status. The medical
determination may provide additional removal time past 18 months for
some employees or specify special protective measures to be implemented.
The lead standard provides for a multiple physician review in cases
where the employee wishes a second opinion concerning potential lead
poisoning or toxicity. If an employee wishes a second opinion, he or she
can make an appointment with a physician of his or her choice. This
second physician will review the findings, recommendations or
determinations of the first physician and conduct any examinations,
consultations or tests deemed necessary in an attempt to make a final
medical determination. If the first and second physicians do not agree
in their assessment they must try to resolve their differences. If they
cannot reach an agreement then they must designate a third physician to
resolve the dispute.
The employer must provide examining and consulting physicians with
the following specific information: a copy of the lead regulations and
all appendices, a description of the employee's duties as related to
exposure, the exposure level to lead and any other toxic substances (if
applicable), a description of personal protective equipment used, blood
lead levels, and all prior written medical opinions regarding the
employee in the employer's possession or control. The employer must also
obtain from the physician and provide the employee with a written
medical opinion containing blood lead levels, the physicians's opinion
as to whether the employee is at risk of material impairment to health,
any recommended protective measures for the employee if further exposure
is permitted, as well as any recommended limitations upon an employee's
use of respirators.
Employers must instruct each physician not to reveal to the employer
in writing or in any other way his or her findings, laboratory results,
or diagnoses which are felt to be unrelated to occupational lead
exposure. They must also instruct each physician to advise the employee
of any occupationally or non-occupationally related medical condition
requiring further treatment or evaluation.
The standard provides for the use of respirators where engineering
and other primary controls have not been fully implemented. However, the
use of respirator protection shall not be used in lieu of temporary
medical removal due to elevated blood lead levels or findings that an
employee is at risk of material health impairment. This is based on the
numerous inadequacies of respirators including skin rash where the
facepiece makes contact with the skin, unacceptable stress to breathing
in some workers with underlying cardiopulmonary impairment, difficulty
in providing adequate fit, the tendency for respirators to create
additional hazards by interfering with vision, hearing, and mobility,
and the difficulties of assuring the maximum effectiveness of a
complicated work practice program involving respirators. Respirators do,
however, serve a useful function where engineering and work practice
controls are inadequate by providing supplementary, interim, or short-
term protection, provided they are properly selected for the environment
in which the employee will be working, properly fitted to the employee,
maintained and cleaned periodically, and worn by the employee when
required.
In its final standard on occupational exposure to inorganic lead,
OSHA has prohibited prophylactic chelation. Diagnostic and therapeutic
chelation are permitted only under the supervision of a licensed
physician with appropriate medical monitoring in an acceptable clinical
setting. The decision to initiate chelation therapy must be made on an
individual basis and take into account the severity of symptoms felt to
be a result of lead toxicity along with blood lead levels, ZPP levels,
and other laboratory tests as appropriate. EDTA and penicillamine which
are the primary chelating agents used in the therapy of occupational
lead poisoning have
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significant potential side effects and their use must be justified on
the basis of expected benefits to the worker. Unless frank and severe
symptoms are present, therapeutic chelation is not recommended given the
opportunity to remove a worker from exposure and allow the body to
naturally excrete accumulated lead. As a diagnostic aid, the chelation
mobilization test using CA-EDTA has limited applicability. According to
some investigators, the test can differentiate between lead-induced and
other nephropathies. The test may also provide an estimation of the
mobile fraction of the total body lead burden.
Employers are required to assure that accurate records are
maintained on exposure monitoring, medical surveillance, and medical
removal for each employee. Exposure monitoring and medical surveillance
records must be kept for 40 years or the duration of employment plus 20
years, whichever is longer, while medical removal records must be
maintained for the duration of employment. All records required under
the standard must be made available upon request to the Assistant
Secretary of Labor for Occupational Safety and Health and the Director
of the National Institute for Occupational Safety and Health. Employers
must also make environmental and biological monitoring and medical
removal records available to affected employees and to former employees
or their authorized employee representatives. Employees or their
specifically designated representatives have access to their entire
medical surveillance records.
In addition, the standard requires that the employer inform all
workers exposed to lead at or above the action level of the provisions
of the standard and all its appendices, the purpose and description of
medical surveillance and provisions for medical removal protection if
temporary removal is required. An understanding of the potential health
effects of lead exposure by all exposed employees along with full
understanding of their rights under the lead standard is essential for
an effective monitoring program.
ii. adverse health effects of inorganic lead
Although the toxicity of lead has been known for 2,000 years, the
knowledge of the complex relationship between lead exposure and human
response is still being refined. Significant research into the toxic
properties of lead continues throughout the world, and it should be
anticipated that our understanding of thresholds of effects and margins
of safety will be improved in future years. The provisions of the lead
standard are founded on two prime medical judgments: first, the
prevention of adverse health effects from exposure to lead throughout a
working lifetime requires that worker blood lead levels be maintained at
or below 40 [micro]g/100 g and second, the blood lead levels of workers,
male or female, who intend to parent in the near future should be
maintained below 30 [micro]g/100 g to minimize adverse reproductive
health effects to the parents and developing fetus. The adverse effects
of lead on reproduction are being actively researched and OSHA
encourages the physician to remain abreast of recent developments in the
area to best advise pregnant workers or workers planning to conceive
children.
The spectrum of health effects caused by lead exposure can be
subdivided into five developmental stages: normal, physiological changes
of uncertain significance, pathophysiological changes, overt symptoms
(morbidity), and mortality. Within this process there are no sharp
distinctions, but rather a continuum of effects. Boundaries between
categories overlap due to the wide variation of individual responses and
exposures in the working population. OSHA's development of the lead
standard focused on pathophysiological changes as well as later stages
of disease.
1. Heme Synthesis Inhibition. The earliest demonstrated effect of
lead involves its ability to inhibit at least two enzymes of the heme
synthesis pathway at very low blood levels. Inhibition of delta
aminolevulinic acid dehydrase (ALA-D) which catalyzes the conversion of
delta-aminolevulinic acid (ALA) to protoporphyrin is observed at a blood
lead level below 20 [micro]g/100 g whole blood. At a blood lead level of
40 ug/100 g, more than 20% of the population would have 70% inhibition
of ALA-D. There is an exponential increase in ALA excretion at blood
lead levels greater than 40 [micro]g/100 g.
Another enzyme, ferrochelatase, is also inhibited at low blood lead
levels. Inhibition of ferrochelatase leads to increased free erythrocyte
protoporphyrin (FEP) in the blood which can then bind to zinc to yield
zinc protoporphyrin. At a blood lead level of 50 [micro]g/100 g or
greater, nearly 100% of the population will have an increase in FEP.
There is also an exponential relationship between blood lead levels
greater than 40 [micro]g/100 g and the associated ZPP level, which has
led to the development of the ZPP screening test for lead exposure.
While the significance of these effects is subject to debate, it is
OSHA's position that these enzyme disturbances are early stages of a
disease process which may eventually result in the clinical symptoms of
lead poisoning. Whether or not the effects do progress to the later
stages of clinical disease, disruption of these enzyme processes over a
working lifetime is considered to be a material impairment of health.
One of the eventual results of lead-induced inhibition of enzymes in
the heme synthesis pathway is anemia which can be asymptomatic if mild
but associated with a wide
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array of symptoms including dizziness, fatigue, and tachycardia when
more severe. Studies have indicated that lead levels as low as 50
[micro]g/100 g can be associated with a definite decreased hemoglobin,
although most cases of lead-induced anemia, as well as shortened red-
cell survival times, occur at lead levels exceeding 80 [micro]g/100 g.
Inhibited hemoglobin synthesis is more common in chronic cases whereas
shortened erythrocyte life span is more common in acute cases.
In lead-induced anemias, there is usually a reticulocytosis along
with the presence of basophilic stippling, and ringed sideroblasts,
although none of the above are pathognomonic for lead-induced anemia.
2. Neurological Effects. Inorganic lead has been found to have toxic
effects on both the central and peripheral nervous systems. The earliest
stages of lead-induced central nervous system effects first manifest
themselves in the form of behavioral disturbances and central nervous
system symptoms including irritability, restlessness, insomnia and other
sleep disturbances, fatigue, vertigo, headache, poor memory, tremor,
depression, and apathy. With more severe exposure, symptoms can progress
to drowsiness, stupor, hallucinations, delerium, convulsions and coma.
The most severe and acute form of lead poisoning which usually
follows ingestion or inhalation of large amounts of lead is acute
encephalopathy which may arise precipitously with the onset of
intractable seizures, coma, cardiorespiratory arrest, and death within
48 hours.
While there is disagreement about what exposure levels are needed to
produce the earliest symptoms, most experts agree that symptoms
definitely can occur at blood lead levels of 60 [micro]g/100 g whole
blood and therefore recommend a 40 [micro]g/100 g maximum. The central
nervous system effects frequently are not reversible following
discontinued exposure or chelation therapy and when improvement does
occur, it is almost always only partial.
The peripheral neuropathy resulting from lead exposure
characteristically involves only motor function with minimal sensory
damage and has a marked predilection for the extensor muscles of the
most active extremity. The peripheral neuropathy can occur with varying
degrees of severity. The earliest and mildest form which can be detected
in workers with blood lead levels as low as 50 [micro]g/100 g is
manifested by slowing of motor nerve conduction velocity often without
clinical symptoms. With progression of the neuropathy there is
development of painless extensor muscle weakness usually involving the
extensor muscles of the fingers and hand in the most active upper
extremity, followed in severe cases by wrist drop or, much less
commonly, foot drop.
In addition to slowing of nerve conduction, electromyographical
studies in patients with blood lead levels greater than 50 [micro]g/100
g have demonstrated a decrease in the number of acting motor unit
potentials, an increase in the duration of motor unit potentials, and
spontaneous pathological activity including fibrillations and
fasciculations. Whether these effects occur at levels of 40 [micro]g/100
g is undetermined.
While the peripheral neuropathies can occasionally be reversed with
therapy, again such recovery is not assured particularly in the more
severe neuropathies and often improvement is only partial. The lack of
reversibility is felt to be due in part to segmental demyelination.
3. Gastrointestinal. Lead may also affect the gastrointestinal
system producing abdominal colic or diffuse abdominal pain,
constipation, obstipation, diarrhea, anorexia, nausea and vomiting. Lead
colic rarely develops at blood lead levels below 80 [micro]g/100 g.
4. Renal. Renal toxicity represents one of the most serious health
effects of lead poisoning. In the early stages of disease nuclear
inclusion bodies can frequently be identified in proximal renal tubular
cells. Renal function remains normal and the changes in this stage are
probably reversible. With more advanced disease there is progressive
interstitial fibrosis and impaired renal function. Eventually extensive
interstitial fibrosis ensues with sclerotic glomeruli and dilated and
atrophied proximal tubules; all represent end stage kidney disease.
Azotemia can be progressive, eventually resulting in frank uremia
necessitating dialysis. There is occasionally associated hypertension
and hyperuricemia with or without gout.
Early kidney disease is difficult to detect. The urinalysis is
normal in early lead nephropathy and the blood urea nitrogen and serum
creatinine increase only when two-thirds of kidney function is lost.
Measurement of creatinine clearance can often detect earlier disease as
can other methods of measurement of glomerular filtration rate. An
abnormal Ca-EDTA mobilization test has been used to differentiate
between lead-induced and other nephropathies, but this procedure is not
widely accepted. A form of Fanconi syndrome with aminoaciduria,
glycosuria, and hyperphosphaturia indicating severe injury to the
proximal renal tubules is occasionally seen in children.
5. Reproductive effects. Exposure to lead can have serious effects
on reproductive function in both males and females. In male workers
exposed to lead there can be a decrease in sexual drive, impotence,
decreased ability to produce healthy sperm, and sterility. Malformed
sperm (teratospermia), decreased number of sperm (hypospermia), and
sperm with decreased motility (asthenospermia) can all occur.
Teratospermia has been noted at mean blood lead levels of 53 [micro]g/
100 g and hypospermia and asthenospermia at 41 [micro]g/100 g.
Furthermore, there appears to be a dose-
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response relationship for teratospermia in lead exposed workers.
Women exposed to lead may experience menstrual disturbances
including dysmenorrhea, menorrhagia and amenorrhea. Following exposure
to lead, women have a higher frequency of sterility, premature births,
spontaneous miscarriages, and stillbirths.
Germ cells can be affected by lead and cause genetic damage in the
egg or sperm cells before conception and result in failure to implant,
miscarriage, stillbirth, or birth defects.
Infants of mothers with lead poisoning have a higher mortality
during the first year and suffer from lowered birth weights, slower
growth, and nervous system disorders.
Lead can pass through the placental barrier and lead levels in the
mother's blood are comparable to concentrations of lead in the umbilical
cord at birth. Transplacental passage becomes detectable at 12-14 weeks
of gestation and increases until birth.
There is little direct data on damage to the fetus from exposure to
lead but it is generally assumed that the fetus and newborn would be at
least as susceptible to neurological damage as young children. Blood
lead levels of 50-60 [micro]g/100 g in children can cause significant
neurobehavioral impairments and there is evidence of hyperactivity at
blood levels as low as 25 [micro]g/100 g. Given the overall body of
literature concerning the adverse health effects of lead in children,
OSHA feels that the blood lead level in children should be maintained
below 30 [micro]g/100 g with a population mean of 15 [micro]g/100 g.
Blood lead levels in the fetus and newborn likewise should not exceed 30
[micro]g/100 g.
Because of lead's ability to pass through the placental barrier and
also because of the demonstrated adverse effects of lead on reproductive
function in both the male and female as well as the risk of genetic
damage of lead on both the ovum and sperm, OSHA recommends a 30
[micro]g/100 g maximum permissible blood lead level in both males and
females who wish to bear children.
6. Other toxic effects. Debate and research continue on the effects
of lead on the human body. Hypertension has frequently been noted in
occupationally exposed individuals although it is difficult to assess
whether this is due to lead's adverse effects on the kidney or if some
other mechanism is involved. Vascular and electrocardiogarphic changes
have been detected but have not been well characterized. Lead is thought
to impair thyroid function and interfere with the pituitary-adrenal
axis, but again these effects have not been well defined.
iii. medical evaluation
The most important principle in evaluating a worker for any
occupational disease including lead poisoning is a high index of
suspicion on the part of the examining physician. As discussed in
Section 2, lead can affect numerous organ systems and produce a wide
array of signs and symptoms, most of which are non-specific and subtle
in nature at least in the early stages of disease. Unless serious
concern for lead toxicity is present, many of the early clues to
diagnosis may easily be overlooked.
The crucial initial step in the medical evaluation is recognizing
that a worker's employment can result in exposure to lead. The worker
will frequently be able to define exposures to lead and lead containing
materials but often will not volunteer this information unless
specifically asked. In other situations the worker may not know of any
exposures to lead but the suspicion might be raised on the part of the
physician because of the industry or occupation of the worker. Potential
occupational exposure to lead and its compounds occur in at least 120
occupations, including lead smelting, the manufacture of lead storage
batteries, the manufacture of lead pigments and products containing
pigments, solder manufacture, shipbuilding and ship repair, auto
manufacturing, construction, and painting.
Once the possibility for lead exposure is raised, the focus can then
be directed toward eliciting information from the medical history,
physical exam, and finally from laboratory data to evaluate the worker
for potential lead toxicity.
A complete and detailed work history is important in the initial
evaluation. A listing of all previous employment with information on
work processes, exposure to fumes or dust, known exposures to lead or
other toxic substances, respiratory protection used, and previous
medical surveillance should all be included in the worker's record.
Where exposure to lead is suspected, information concerning on-the-job
personal hygiene, smoking or eating habits in work areas, laundry
procedures, and use of any protective clothing or respiratory protection
equipment should be noted. A complete work history is essential in the
medical evaluation of a worker with suspected lead toxicity, especially
when long term effects such as neurotoxicity and nephrotoxicity are
considered.
The medical history is also of fundamental importance and should
include a listing of all past and current medical conditions, current
medications including proprietary drug intake, previous surgeries and
hospitalizations, allergies, smoking history, alcohol consumption, and
also non-occupational lead exposures such as hobbies (hunting, riflery).
Also known childhood exposures should be elicited. Any previous history
of hematological, neurological, gastrointestinal, renal, psychological,
gynecological, genetic, or reproductive problems should be specifically
noted.
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A careful and complete review must be performed to assess both
recognized complaints and subtle or slowly acquired symptoms which the
worker might not appreciate as being significant. The review of symptoms
should include the following:
General--weight loss, fatigue, decreased appetite.
Head, Eyes, Ears, Nose, Throat (HEENT)--headaches, visual
disturbances or decreased visual acuity, hearing deficits or tinnitus,
pigmentation of the oral mucosa, or metallic taste in mouth.
Cardio-pulmonary--shortness of breath, cough, chest pains,
palpitations, or orthopnea.
Gastrointestinal--nausea, vomiting, heartburn, abdominal pain,
constipation or diarrhea.
Neurologic--irritability, insomnia, weakness (fatigue), dizziness,
loss of memory, confusion, hallucinations, incoordination, ataxia,
decreased strength in hands or feet, disturbances in gait, difficulty in
climbing stairs, or seizures.
Hematologic--pallor, easy fatigability, abnormal blood loss, melena.
Reproductive (male and female and spouse where relevant)--history of
infertility, impotence, loss of libido, abnormal menstrual periods,
history of miscarriages, stillbirths, or children with birth defects.
Musculo-skeletal--muscle and joint pains.
The physical examination should emphasize the neurological,
gastrointestinal, and cardiovascular systems. The worker's weight and
blood pressure should be recorded and the oral mucosa checked for
pigmentation characteristic of a possible Burtonian or lead line on the
gingiva. It should be noted, however, that the lead line may not be
present even in severe lead poisoning if good oral hygiene is practiced.
The presence of pallor on skin examination may indicate an anemia,
which if severe might also be associated with a tachycardia. If an
anemia is suspected, an active search for blood loss should be
undertaken including potential blood loss through the gastrointestinal
tract.
A complete neurological examination should include an adequate
mental status evaluation including a search for behavioral and
psychological disturbances, memory testing, evaluation for irritability,
insomnia, hallucinations, and mental clouding. Gait and coordination
should be examined along with close observation for tremor. A detailed
evaluation of peripheral nerve function including careful sensory and
motor function testing is warranted. Strength testing particularly of
extensor muscle groups of all extremities is of fundamental importance.
Cranial nerve evaluation should also be included in the routine
examination.
The abdominal examination should include auscultation for bowel
sounds and abdominal bruits and palpation for organomegaly, masses, and
diffuse abdominal tenderness.
Cardiovascular examination should evaluate possible early signs of
congestive heart failure. Pulmonary status should be addressed
particularly if respirator protection is contemplated.
As part of the medical evaluation, the lead standard requires the
following laboratory studies:
1. Blood lead level
2. Hemoglobin and hematocrit determinations, red cell indices, and
examination of the peripheral blood smear to evaluate red blood cell
morphology
3. Blood urea nitrogen
4. Serum creatinine
5. Routine urinalysis with microscopic examination.
6. A zinc protoporphyrin level
In addition to the above, the physician is authorized to order any
further laboratory or other tests which he or she deems necessary in
accordance with sound medical practice. The evaluation must also include
pregnancy testing or laboratory evaluation of male fertility if
requested by the employee.
Additional tests which are probably not warranted on a routine basis
but may be appropriate when blood lead and ZPP levels are equivocal
include delta aminolevulinic acid and coproporphyrin concentrations in
the urine, and dark-field illumination for detection of basophilic
stippling in red blood cells.
If an anemia is detected further studies including a careful
examination of the peripheral smear, reticulocyte count, stool for
occult blood, serum iron, total iron binding capacity, bilirubin, and,
if appropriate, vitamin B12 and folate may be of value in attempting to
identify the cause of the anemia.
If a peripheral neuropathy is suspected, nerve conduction studies
are warranted both for diagnosis and as a basis to monitor any therapy.
If renal disease is questioned, a 24 hour urine collection for
creatinine clearance, protein, and electrolytes may be indicated.
Elevated uric acid levels may result from lead-induced renal disease and
a serum uric acid level might be performed.
An electrocardiogram and chest x-ray may be obtained as deemed
appropriate.
Sophisticated and highly specialized testing should not be done
routinely and where indicated should be under the direction of a
specialist.
iv. laboratory evaluation
The blood lead level at present remains the single most important
test to monitor lead exposure and is the test used in the medical
surveillance program under the lead standard to guide employee medical
removal. The ZPP has several advantages over the blood
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lead level. Because of its relatively recent development and the lack of
extensive data concerning its interpretation, the ZPP currently remains
an ancillary test.
This section will discuss the blood lead level and ZPP in detail and
will outline their relative advantages and disadvantages. Other blood
tests currently available to evaluate lead exposure will also be
reviewed.
The blood lead level is a good index of current or recent lead
absorption when there is no anemia present and when the worker has not
taken any chelating agents. However, blood lead levels along with
urinary lead levels do not necessarily indicate the total body burden of
lead and are not adequate measures of past exposure. One reason for this
is that lead has a high affinity for bone and up to 90% of the body's
total lead is deposited there. A very important component of the total
lead body burden is lead in soft tissue (liver, kidney, and brain). This
fraction of the lead body burden, the biologically active lead, is not
entirely reflected by blood lead levels since it is a function of the
dynamics of lead absorption, distribution, deposition in bone and
excretion. Following discontinuation of exposure to lead, the excess
body burden is only slowly mobilized from bone and other relatively
stable body stores and excreted. Consequently, a high blood lead level
may only represent recent heavy exposure to lead without a significant
total body excess and likewise a low blood lead level does not exclude
an elevated total body burden of lead.
Also due to its correlation with recent exposures, the blood lead
level may vary considerably over short time intervals.
To minimize laboratory error and erroneous results due to
contamination, blood specimens must be carefully collected after
thorough cleaning of the skin with appropriate methods using lead-free
blood containers and analyzed by a reliable laboratory. Under the
standard, samples must be analyzed in laboratories which are approved by
the Center for Disease Control (CDC) or which have received satisfactory
grades in proficiency testing by the CDC in the previous year. Analysis
is to be made using atomic absorption spectrophotometry, anodic
stripping voltammetry or any method which meets the accuracy
requirements set forth by the standard.
The determination of lead in urine is generally considered a less
reliable monitoring technique than analysis of whole blood primarily due
to individual variability in urinary excretion capacity as well as the
technical difficulty of obtaining accurate 24 hour urine collections. In
addition, workers with renal insufficiency, whether due to lead or some
other cause, may have decreased lead clearance and consequently urine
lead levels may underestimate the true lead burden. Therefore, urine
lead levels should not be used as a routine test.
The zinc protoporphyrin test, unlike the blood lead determination,
measures an adverse metabolic effect of lead and as such is a better
indicator of lead toxicity than the level of blood lead itself. The
level of ZPP reflects lead absorption over the preceding 3 to 4 months,
and therefore is a better indicator of lead body burden. The ZPP
requires more time than the blood lead to read significantly elevated
levels; the return to normal after discontinuing lead exposure is also
slower. Furthermore, the ZPP test is simpler, faster, and less expensive
to perform and no contamination is possible. Many investigators believe
it is the most reliable means of monitoring chronic lead absorption.
Zinc protoporphyrin results from the inhibition of the enzyme
ferrochelatase which catalyzes the insertion of an iron molecule into
the protoporphyrin molecule, which then becomes heme. If iron is not
inserted into the molecule then zinc, having a greater affinity for
protoporphyrin, takes the place of the iron, forming ZPP.
An elevation in the level of circulating ZPP may occur at blood lead
levels as low as 20-30 [micro]g/100 g in some workers. Once the blood
lead level has reached 40 [micro]g/100 g there is more marked rise in
the ZPP value from its normal range of less than 100 [micro]g/100 ml.
Increases in blood lead levels beyond 40 [micro]g/100 g are associated
with exponential increases in ZPP.
Whereas blood lead levels fluctuate over short time spans, ZPP
levels remain relatively stable. ZPP is measured directly in red blood
cells and is present for the cell's entire 120 day life-span. Therefore,
the ZPP level in blood reflects the average ZPP production over the
previous 3-4 months and consequently the average lead exposure during
that time interval.
It is recommended that a hematocrit be determined whenever a
confirmed ZPP of 50 [micro]g/100 ml whole blood is obtained to rule out
a significant underlying anemia. If the ZPP is in excess of 100
[micro]g/100 ml and not associated with abnormal elevations in blood
lead levels, the laboratory should be checked to be sure that blood
leads were determined using atomic absorption spectrophotometry anodic
stripping voltammetry, or any method which meets the accuracy
requirements set forth by the standard by a CDC approved laboratory
which is experienced in lead level determinations. Repeat periodic blood
lead studies should be obtained in all individuals with elevated ZPP
levels to be certain that an associated elevated blood lead level has
not been missed due to transient fluctuations in blood leads.
ZPP has a characteristic fluorescence spectrum with a peak at 594 nm
which is detectable with a hematofluorimeter. The
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hematofluorimeter is accurate and portable and can provide on-site,
instantaneous results for workers who can be frequently tested via a
finger prick.
However, careful attention must be given to calibration and quality
control procedures. Limited data on blood lead--ZPP correlations and the
ZPP levels which are associated with the adverse health effects
discussed in Section 2 are the major limitations of the test. Also it is
difficult to correlate ZPP levels with environmental exposure and there
is some variation of response with age and sex. Nevertheless, the ZPP
promises to be an important diagnostic test for the early detection of
lead toxicity and its value will increase as more data is collected
regarding its relationship to other manifestations of lead poisoning.
Levels of delta-aminolevulinic acid (ALA) in the urine are also used
as a measure of lead exposure. Increasing concentrations of ALA are
believed to result from the inhibition of the enzyme delta-
aminolevulinic acid dehydrase (ALA-D). Although the test is relatively
easy to perform, inexpensive, and rapid, the disadvantages include
variability in results, the necessity to collect a complete 24 hour
urine sample which has a specific gravity greater than 1.010, and also
the fact that ALA decomposes in the presence of light.
The pattern of porphyrin excretion in the urine can also be helpful
in identifying lead intoxication. With lead poisoning, the urine
concentrations of coproporphyrins I and II, porphobilinogen and
uroporphyrin I rise. The most important increase, however, is that of
coproporphyrin III; levels may exceed 5,000 [micro]g/1 in the urine in
lead poisoned individuals, but its correlation with blood lead levels
and ZPP are not as good as those of ALA. Increases in urinary porphyrins
are not diagnostic of lead toxicity and may be seen in porphyria, some
liver diseases, and in patients with high reticulocyte counts.
Summary. The Occupational Safety and Health Administration's
standard for inorganic lead places significant emphasis on the medical
surveillance of all workers exposed to levels of inorganic lead above
the action level of 30 [micro]g/m\3\ TWA. The physician has a
fundamental role in this surveillance program, and in the operation of
the medical removal protection program.
Even with adequate worker education on the adverse health effects of
lead and appropriate training in work practices, personal hygiene and
other control measures, the physician has a primary responsibility for
evaluating potential lead toxicity in the worker. It is only through a
careful and detailed medical and work history, a complete physical
examination and appropriate laboratory testing that an accurate
assessment can be made. Many of the adverse health effects of lead
toxicity are either irreversible or only partially reversible and
therefore early detection of disease is very important.
This document outlines the medical monitoring program as defined by
the occupational safety and health standard for inorganic lead. It
reviews the adverse health effects of lead poisoning and describes the
important elements of the history and physical examinations as they
relate to these adverse effects. Finally, the appropriate laboratory
testing for evaluating lead exposure and toxicity is presented.
It is hoped that this review and discussion will give the physician
a better understanding of the OSHA standard with the ultimate goal of
protecting the health and well-being of the worker exposed to lead under
his or her care.
[43 FR 53007, Nov. 14, 1978]
Editorial Note: For Federal Register citations affectingSec.
1910.1025 see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and at www.fdsys.gov.
Sec. 1910.1026 Chromium (VI).
(a) Scope. (1) This standard applies to occupational exposures to
chromium (VI) in all forms and compounds in general industry, except:
(2) Exposures that occur in the application of pesticides regulated
by the Environmental Protection Agency or another Federal government
agency (e.g., the treatment of wood with preservatives);
(3) Exposures to portland cement; or
(4) Where the employer has objective data demonstrating that a
material containing chromium or a specific process, operation, or
activity involving chromium cannot release dusts, fumes, or mists of
chromium (VI) in concentrations at or above 0.5 [micro]gm/m\3\ as an 8-
hour time-weighted average (TWA) under any expected conditions of use.
(b) Definitions. For the purposes of this section the following
definitions apply:
Action level means a concentration of airborne chromium (VI) of 2.5
micrograms per cubic meter of air (2.5 [micro]gm/m\3\) calculated as an
8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
[[Page 133]]
Chromium (VI) [hexavalent chromium or Cr(VI)] means chromium with a
valence of positive six, in any form and in any compound.
Director means the Director of the National Institute for
Occupational Safety and Health (NIOSH), U.S. Department of Health and
Human Services, or designee.
Emergency means any occurrence that results, or is likely to result,
in an uncontrolled release of chromium (VI). If an incidental release of
chromium (VI) can be controlled at the time of release by employees in
the immediate release area, or by maintenance personnel, it is not an
emergency.
Employee exposure means the exposure to airborne chromium (VI) that
would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is
at least 99.97 percent efficient in removing mono-dispersed particles of
0.3 micrometers in diameter or larger.
Historical monitoring data means data from chromium (VI) monitoring
conducted prior to May 30, 2006, obtained during work operations
conducted under workplace conditions closely resembling the processes,
types of material, control methods, work practices, and environmental
conditions in the employer's current operations.
Objective data means information such as air monitoring data from
industry-wide surveys or calculations based on the composition or
chemical and physical properties of a substance demonstrating the
employee exposure to chromium (VI) associated with a particular product
or material or a specific process, operation, or activity. The data must
reflect workplace conditions closely resembling the processes, types of
material, control methods, work practices, and environmental conditions
in the employer's current operations.
Physician or other licensed health care professional [PLHCP] is an
individual whose legally permitted scope of practice (i.e., license,
registration, or certification) allows him or her to independently
provide or be delegated the responsibility to provide some or all of the
particular health care services required by paragraph (k) of this
section.
Regulated area means an area, demarcated by the employer, where an
employee's exposure to airborne concentrations of chromium (VI) exceeds,
or can reasonably be expected to exceed, the PEL.
This section means thisSec. 1910.1026 chromium (VI) standard.
(c) Permissible exposure limit (PEL). The employer shall ensure that
no employee is exposed to an airborne concentration of chromium (VI) in
excess of 5 micrograms per cubic meter of air (5 [micro]gm/m\3\),
calculated as an 8-hour time-weighted average (TWA).
(d) Exposure determination--(1) General. Each employer who has a
workplace or work operation covered by this section shall determine the
8-hour TWA exposure for each employee exposed to chromium (VI). This
determination shall be made in accordance with either paragraph (d)(2)
or paragraph (d)(3) of this section.
(2) Scheduled monitoring option. (i) The employer shall perform
initial monitoring to determine the 8-hour TWA exposure for each
employee on the basis of a sufficient number of personal breathing zone
air samples to accurately characterize full shift exposure on each
shift, for each job classification, in each work area. Where an employer
does representative sampling instead of sampling all employees in order
to meet this requirement, the employer shall sample the employee(s)
expected to have the highest chromium (VI) exposures.
(ii) If initial monitoring indicates that employee exposures are
below the action level, the employer may discontinue monitoring for
those employees whose exposures are represented by such monitoring.
(iii) If monitoring reveals employee exposures to be at or above the
action level, the employer shall perform periodic monitoring at least
every six months.
(iv) If monitoring reveals employee exposures to be above the PEL,
the employer shall perform periodic monitoring at least every three
months.
(v) If periodic monitoring indicates that employee exposures are
below the action level, and the result is confirmed by the result of
another monitoring taken at least seven days later,
[[Page 134]]
the employer may discontinue the monitoring for those employees whose
exposures are represented by such monitoring.
(vi) The employer shall perform additional monitoring when there has
been any change in the production process, raw materials, equipment,
personnel, work practices, or control methods that may result in new or
additional exposures to chromium (VI), or when the employer has any
reason to believe that new or additional exposures have occurred.
(3) Performance-oriented option. The employer shall determine the 8-
hour TWA exposure for each employee on the basis of any combination of
air monitoring data, historical monitoring data, or objective data
sufficient to accurately characterize employee exposure to chromium
(VI).
(4) Employee notification of determination results. (i) Within 15
work days after making an exposure determination in accordance with
paragraph (d)(2) or paragraph (d)(3) of this section, the employer shall
individually notify each affected employee in writing of the results of
that determination or post the results in an appropriate location
accessible to all affected employees.
(ii) Whenever the exposure determination indicates that employee
exposure is above the PEL, the employer shall describe in the written
notification the corrective action being taken to reduce employee
exposure to or below the PEL.
(5) Accuracy of measurement. Where air monitoring is performed to
comply with the requirements of this section, the employer shall use a
method of monitoring and analysis that can measure chromium (VI) to
within an accuracy of plus or minus 25 percent (25%) and can produce accurate measurements to within a
statistical confidence level of 95 percent for airborne concentrations
at or above the action level.
(6) Observation of monitoring. (i) Where air monitoring is performed
to comply with the requirements of this section, the employer shall
provide affected employees or their designated representatives an
opportunity to observe any monitoring of employee exposure to chromium
(VI).
(ii) When observation of monitoring requires entry into an area
where the use of protective clothing or equipment is required, the
employer shall provide the observer with clothing and equipment and
shall assure that the observer uses such clothing and equipment and
complies with all other applicable safety and health procedures.
(e) Regulated areas--(1) Establishment. The employer shall establish
a regulated area wherever an employee's exposure to airborne
concentrations of chromium (VI) is, or can reasonably be expected to be,
in excess of the PEL.
(2) Demarcation. The employer shall ensure that regulated areas are
demarcated from the rest of the workplace in a manner that adequately
establishes and alerts employees of the boundaries of the regulated
area.
(3) Access. The employer shall limit access to regulated areas to:
(i) Persons authorized by the employer and required by work duties
to be present in the regulated area;
(ii) Any person entering such an area as a designated representative
of employees for the purpose of exercising the right to observe
monitoring procedures under paragraph (d) of this section; or
(iii) Any person authorized by the Occupational Safety and Health
Act or regulations issued under it to be in a regulated area.
(f) Methods of compliance--(1) Engineering and work practice
controls. (i) Except as permitted in paragraph (f)(1)(ii) and paragraph
(f)(1)(iii) of this section, the employer shall use engineering and work
practice controls to reduce and maintain employee exposure to chromium
(VI) to or below the PEL unless the employer can demonstrate that such
controls are not feasible. Wherever feasible engineering and work
practice controls are not sufficient to reduce employee exposure to or
below the PEL, the employer shall use them to reduce employee exposure
to the lowest levels achievable, and shall supplement them by the use of
respiratory protection that complies with the requirements of paragraph
(g) of this section.
[[Page 135]]
(ii) Where painting of aircraft or large aircraft parts is performed
in the aerospace industry, the employer shall use engineering and work
practice controls to reduce and maintain employee exposure to chromium
(VI) to or below 25 [micro]gm/m\3\ unless the employer can demonstrate
that such controls are not feasible. The employer shall supplement such
engineering and work practice controls with the use of respiratory
protection that complies with the requirements of paragraph (g) of this
section to achieve the PEL.
(iii) Where the employer can demonstrate that a process or task does
not result in any employee exposure to chromium (VI) above the PEL for
30 or more days per year (12 consecutive months), the requirement to
implement engineering and work practice controls to achieve the PEL does
not apply to that process or task.
(2) Prohibition of rotation. The employer shall not rotate employees
to different jobs to achieve compliance with the PEL.
(g) Respiratory protection--(1) General. Where respiratory
protection is required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respiratory protection is required during:
(i) Periods necessary to install or implement feasible engineering
and work practice controls;
(ii) Work operations, such as maintenance and repair activities, for
which engineering and work practice controls are not feasible;
(iii) Work operations for which an employer has implemented all
feasible engineering and work practice controls and such controls are
not sufficient to reduce exposures to or below the PEL;
(iv) Work operations where employees are exposed above the PEL for
fewer than 30 days per year, and the employer has elected not to
implement engineering and work practice controls to achieve the PEL; or
(v) Emergencies.
(2) Respiratory protection program. Where respirator use is required
by this section, the employer shall institute a respiratory protection
program in accordance withSec. 1910.134, which covers each employee
required to use a respirator.
(h) Protective work clothing and equipment--(1) Provision and use.
Where a hazard is present or is likely to be present from skin or eye
contact with chromium (VI), the employer shall provide appropriate
personal protective clothing and equipment at no cost to employees, and
shall ensure that employees use such clothing and equipment.
(2) Removal and storage. (i) The employer shall ensure that
employees remove all protective clothing and equipment contaminated with
chromium (VI) at the end of the work shift or at the completion of their
tasks involving chromium (VI) exposure, whichever comes first.
(ii) The employer shall ensure that no employee removes chromium
(VI)-contaminated protective clothing or equipment from the workplace,
except for those employees whose job it is to launder, clean, maintain,
or dispose of such clothing or equipment.
(iii) When contaminated protective clothing or equipment is removed
for laundering, cleaning, maintenance, or disposal, the employer shall
ensure that it is stored and transported in sealed, impermeable bags or
other closed, impermeable containers.
(iv) The employer shall ensure that bags or containers of
contaminated protective clothing or equipment that are removed from
change rooms for laundering, cleaning, maintenance, or disposal are
labeled in accordance with the requirements of the Hazard Communication
Standard,Sec. 1910.1200.
(3) Cleaning and replacement. (i) The employer shall clean, launder,
repair and replace all protective clothing and equipment required by
this section as needed to maintain its effectiveness.
(ii) The employer shall prohibit the removal of chromium (VI) from
protective clothing and equipment by blowing, shaking, or any other
means that disperses chromium (VI) into the air or onto an employee's
body.
(iii) The employer shall inform any person who launders or cleans
protective clothing or equipment contaminated with chromium (VI) of the
potentially harmful effects of exposure to chromium (VI) and that the
clothing
[[Page 136]]
and equipment should be laundered or cleaned in a manner that minimizes
skin or eye contact with chromium (VI) and effectively prevents the
release of airborne chromium (VI) in excess of the PEL.
(i) Hygiene areas and practices--(1) General. Where protective
clothing and equipment is required, the employer shall provide change
rooms in conformance with 29 CFR 1910.141. Where skin contact with
chromium (VI) occurs, the employer shall provide washing facilities in
conformance with 29 CFR 1910.141. Eating and drinking areas provided by
the employer shall also be in conformance withSec. 1910.141.
(2) Change rooms. The employer shall assure that change rooms are
equipped with separate storage facilities for protective clothing and
equipment and for street clothes, and that these facilities prevent
cross-contamination.
(3) Washing facilities. (i) The employer shall provide readily
accessible washing facilities capable of removing chromium (VI) from the
skin, and shall ensure that affected employees use these facilities when
necessary.
(ii) The employer shall ensure that employees who have skin contact
with chromium (VI) wash their hands and faces at the end of the work
shift and prior to eating, drinking, smoking, chewing tobacco or gum,
applying cosmetics, or using the toilet.
(4) Eating and drinking areas. (i) Whenever the employer allows
employees to consume food or beverages at a worksite where chromium (VI)
is present, the employer shall ensure that eating and drinking areas and
surfaces are maintained as free as practicable of chromium (VI).
(ii) The employer shall ensure that employees do not enter eating
and drinking areas with protective work clothing or equipment unless
surface chromium (VI) has been removed from the clothing and equipment
by methods that do not disperse chromium (VI) into the air or onto an
employee's body.
(5) Prohibited activities. The employer shall ensure that employees
do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in
regulated areas, or in areas where skin or eye contact with chromium
(VI) occurs; or carry the products associated with these activities, or
store such products in these areas.
(j) Housekeeping--(1) General. The employer shall ensure that:
(i) All surfaces are maintained as free as practicable of
accumulations of chromium (VI).
(ii) All spills and releases of chromium (VI) containing material
are cleaned up promptly.
(2) Cleaning methods. (i) The employer shall ensure that surfaces
contaminated with chromium (VI) are cleaned by HEPA-filter vacuuming or
other methods that minimize the likelihood of exposure to chromium (VI).
(ii) Dry shoveling, dry sweeping, and dry brushing may be used only
where HEPA-filtered vacuuming or other methods that minimize the
likelihood of exposure to chromium (VI) have been tried and found not to
be effective.
(iii) The employer shall not allow compressed air to be used to
remove chromium (VI) from any surface unless:
(A) The compressed air is used in conjunction with a ventilation
system designed to capture the dust cloud created by the compressed air;
or
(B) No alternative method is feasible.
(iv) The employer shall ensure that cleaning equipment is handled in
a manner that minimizes the reentry of chromium (VI) into the workplace.
(3) Disposal. The employer shall ensure that:
(i) Waste, scrap, debris, and any other materials contaminated with
chromium (VI) and consigned for disposal are collected and disposed of
in sealed, impermeable bags or other closed, impermeable containers.
(ii) Bags or containers of waste, scrap, debris, and any other
materials contaminated with chromium (VI) that are consigned for
disposal are labeled in accordance with the requirements of the Hazard
Communication Standard, 29 CFR 1910.1200.
(k) Medical surveillance--(1) General. (i) The employer shall make
medical surveillance available at no cost to the employee, and at a
reasonable time and place, for all employees:
(A) Who are or may be occupationally exposed to chromium (VI) at or
[[Page 137]]
above the action level for 30 or more days a year;
(B) Experiencing signs or symptoms of the adverse health effects
associated with chromium (VI) exposure; or
(C) Exposed in an emergency.
(ii) The employer shall assure that all medical examinations and
procedures required by this section are performed by or under the
supervision of a PLHCP.
(2) Frequency. The employer shall provide a medical examination:
(i) Within 30 days after initial assignment, unless the employee has
received a chromium (VI) related medical examination that meets the
requirements of this paragraph within the last twelve months;
(ii) Annually;
(iii) Within 30 days after a PLHCP's written medical opinion
recommends an additional examination;
(iv) Whenever an employee shows signs or symptoms of the adverse
health effects associated with chromium (VI) exposure;
(v) Within 30 days after exposure during an emergency which results
in an uncontrolled release of chromium (VI); or
(vi) At the termination of employment, unless the last examination
that satisfied the requirements of paragraph (k) of this section was
less than six months prior to the date of termination.
(3) Contents of examination. A medical examination consists of:
(i) A medical and work history, with emphasis on: Past, present, and
anticipated future exposure to chromium (VI); any history of respiratory
system dysfunction; any history of asthma, dermatitis, skin ulceration,
or nasal septum perforation; and smoking status and history;
(ii) A physical examination of the skin and respiratory tract; and
(iii) Any additional tests deemed appropriate by the examining
PLHCP.
(4) Information provided to the PLHCP. The employer shall ensure
that the examining PLHCP has a copy of this standard, and shall provide
the following information:
(i) A description of the affected employee's former, current, and
anticipated duties as they relate to the employee's occupational
exposure to chromium (VI);
(ii) The employee's former, current, and anticipated levels of
occupational exposure to chromium (VI);
(iii) A description of any personal protective equipment used or to
be used by the employee, including when and for how long the employee
has used that equipment; and
(iv) Information from records of employment-related medical
examinations previously provided to the affected employee, currently
within the control of the employer.
(5) PLHCP's written medical opinion. (i) The employer shall obtain a
written medical opinion from the PLHCP, within 30 days for each medical
examination performed on each employee, which contains:
(A) The PLHCP's opinion as to whether the employee has any detected
medical condition(s) that would place the employee at increased risk of
material impairment to health from further exposure to chromium (VI);
(B) Any recommended limitations upon the employee's exposure to
chromium (VI) or upon the use of personal protective equipment such as
respirators;
(C) A statement that the PLHCP has explained to the employee the
results of the medical examination, including any medical conditions
related to chromium (VI) exposure that require further evaluation or
treatment, and any special provisions for use of protective clothing or
equipment.
(ii) The PLHCP shall not reveal to the employer specific findings or
diagnoses unrelated to occupational exposure to chromium (VI).
(iii) The employer shall provide a copy of the PLHCP's written
medical opinion to the examined employee within two weeks after
receiving it.
(l) Communication of chromium (VI) hazards to employees.--(1) Hazard
communication--general--(i) Chemical manufacturers, importers,
distributors and employers shall comply with all requirements of the
Hazard Communication Standard (HCS) (Sec. 1910.1200) for chromium (VI).
[[Page 138]]
(ii) In classifying the hazards of chromium (VI) at least the
following hazards are to be addressed: Cancer, eye irritation, and skin
sensitization.
(iii) Employers shall include chromium (VI) in the hazard
communication program established to comply with the HCS (Sec.
1910.1200). Employers shall ensure that each employee has access to
labels on containers of chromium (VI) and to safety data sheets, and is
trained in accordance with the requirements of HCS and paragraph (l)(2)
of this section.
(2) Employee information and training. (i) The employer shall ensure
that each employee can demonstrate knowledge of at least the following:
(A) The contents of this section; and
(B) The purpose and a description of the medical surveillance
program required by paragraph (k) of this section.
(ii) The employer shall make a copy of this section readily
available without cost to all affected employees.
(m) Recordkeeping--(1) Air monitoring data. (i) The employer shall
maintain an accurate record of all air monitoring conducted to comply
with the requirements of this section.
(ii) This record shall include at least the following information:
(A) The date of measurement for each sample taken;
(B) The operation involving exposure to chromium (VI) that is being
monitored;
(C) Sampling and analytical methods used and evidence of their
accuracy;
(D) Number, duration, and the results of samples taken;
(E) Type of personal protective equipment, such as respirators worn;
and
(F) Name, social security number, and job classification of all
employees represented by the monitoring, indicating which employees were
actually monitored.
(iii) The employer shall ensure that exposure records are maintained
and made available in accordance with 29 CFR 1910.1020.
(2) Historical monitoring data. (i) Where the employer has relied on
historical monitoring data to determine exposure to chromium (VI), the
employer shall establish and maintain an accurate record of the
historical monitoring data relied upon.
(ii) The record shall include information that reflects the
following conditions:
(A) The data were collected using methods that meet the accuracy
requirements of paragraph (d)(5) of this section;
(B) The processes and work practices that were in use when the
historical monitoring data were obtained are essentially the same as
those to be used during the job for which exposure is being determined;
(C) The characteristics of the chromium (VI) containing material
being handled when the historical monitoring data were obtained are the
same as those on the job for which exposure is being determined;
(D) Environmental conditions prevailing when the historical
monitoring data were obtained are the same as those on the job for which
exposure is being determined; and
(E) Other data relevant to the operations, materials, processing, or
employee exposures covered by the exception.
(iii) The employer shall ensure that historical exposure records are
maintained and made available in accordance with 29 CFR 1910.1020.
(3) Objective data. (i) The employer shall maintain an accurate
record of all objective data relied upon to comply with the requirements
of this section.
(ii) This record shall include at least the following information:
(A) The chromium containing material in question;
(B) The source of the objective data;
(C) The testing protocol and results of testing, or analysis of the
material for the release of chromium (VI);
(D) A description of the process, operation, or activity and how the
data support the determination; and
(E) Other data relevant to the process, operation, activity,
material, or employee exposures.
(iii) The employer shall ensure that objective data are maintained
and made available in accordance with 29 CFR 1910.1020.
(4) Medical surveillance. (i) The employer shall establish and
maintain an
[[Page 139]]
accurate record for each employee covered by medical surveillance under
paragraph (k) of this section.
(ii) The record shall include the following information about the
employee:
(A) Name and social security number;
(B) A copy of the PLHCP's written opinions;
(C) A copy of the information provided to the PLHCP as required by
paragraph (k)(4) of this section.
(iii) The employer shall ensure that medical records are maintained
and made available in accordance with 29 CFR 1910.1020.
(n) Dates. (1) For employers with 20 or more employees, all
obligations of this section, except engineering controls required by
paragraph (f) of this section, commence November 27, 2006.
(2) For employers with 19 or fewer employees, all obligations of
this section, except engineering controls required by paragraph (f) of
this section, commence May 30, 2007.
(3) Except as provided in (n)(4), for all employers, engineering
controls required by paragraph (f) of this section shall be implemented
no later than May 31, 2010.
(4) In facilities that become parties to the settlement agreement
included in appendix A, engineering controls required by paragraph (f)
of this section shall be implemented no later than December 31, 2008.
Appendix A toSec. 1910.1026
In the United States Court of Appeals for the Third Circuit
Surface Finishing Industry Council et al., Petitioners, v. U.S.
Occupational Safety and Health Administration, Respondent.
[Docket No. 06-2272 and consolidated cases]
Public Citizen Health Research Group et al., Petitioners, v.
Occupational Safety and Health Administration, United States Department
of Labor, Respondent.
[Docket No. 06-1818]
Settlement Agreement
The parties to this Settlement Agreement (``Agreement'') are the
Occupational Safety and Health Administration, United States Department
of Labor (``OSHA''), the Surface Finishing Industry Council or its
successors (``SFIC''), surface-finishing and metal-finishing facilities
which have opted into this Agreement pursuant to paragraph 7
(``Company'' or ``Companies''), Public Citizen Health Research Group
(``HRG''), and the United Steel, Paper and Forestry, Rubber,
Manufacturing, Energy, Allied Industrial and Service Workers
International Union (``Steelworkers'').
Whereas, On February 28, 2006, OSHA promulgated a revised hexavalent
chromium standard for general industry (``the Standard'') that includes
a permissible exposure limit (``PEL'') for hexavalent chromium of 5
micrograms per cubic meter (``[mu]g/m\3\'') measured as an 8-hour time-
weighted average (``TWA''), and a deadline of May 31, 2010, for
employers to come into compliance with this PEL through the
implementation of engineering controls. The deadline for compliance with
the remaining provisions of the Standard, including those requiring the
use of respiratory protection to comply with the PEL, is November 27,
2006, for employers with twenty (20) or more employees, and May 30,
2007, for employers with nineteen (19) or fewer employees. 29 CFR
1910.1026, 71 FR 10100 (Feb. 28, 2006);
Whereas, SFIC filed a Petition for Review of the Standard in the
Eleventh Circuit that was consolidated with other Petitions in the Third
Circuit (Case No. 06-2272);
Whereas, SFIC filed a Motion for Leave to Intervene in the matter of
HRG's Petition for Review in the Third Circuit (Case No. 06-1818), which
has been granted;
Now, therefore, the parties to this Agreement do hereby agree to the
following terms:
1. Term of this Agreement. This Agreement will be effective upon
execution and will expire on May 31, 2010.
2. Accelerated implementation of engineering controls. The Companies
agree that in accordance with 29 CFR 1910.1026(f)(1) they will implement
those feasible engineering controls necessary to reduce hexavalent
chromium levels at their facilities by December 31, 2008, to or below
the 5 [mu]g/m\3\ PEL. In fulfilling this obligation, the Companies may
select from the engineering and work practice controls listed in Exhibit
A to this Agreement or adopt any other controls.
3. Compliance plan and monitoring. In accordance with 29 CFR
1910.1026(d)(4)(ii), each Company will prepare, and update as required,
a written plan setting forth the specific control steps being taken to
reduce employee exposure to or below the PEL by December 31, 2008. In
addition, Companies will make an initial exposure determination as
required by 29 CFR 1910.1026(d)(1) using either the procedures for
personal breathing zone air samples described in 29 CFR 1910.1026(d)(2)
or the performance-oriented option described at 29 CFR 1910.1026(d)(3).
Thereafter, Companies will conduct periodic monitoring in accordance
with the ``Scheduled Monitoring Option'' provisions at 29
[[Page 140]]
CFR 1910.1026(d)(2) and related provisions at 29 CFR 1910.1026(d)(4)-
(6). The Companies agree that upon request compliance plans prepared in
accordance with this paragraph, as well as all monitoring results
obtained in compliance with this paragraph, will be provided to OSHA,
affected employees and employee representatives.
4. Respirator use. The respiratory protection provisions at 29 CFR
1910.1026(f) and (g) will apply to the Companies in accordance with the
terms and dates set forth in the Standard, except that prior to December
31, 2008, for Companies that are in compliance with this Agreement, OSHA
will enforce those respiratory protection provisions only with respect
to employees who fall into one of the following six (6) categories: (1)
Employees who are exposed to hexavalent chromium in excess of the PEL
while performing tasks described in Exhibit B to this Agreement; (2)
through November 30, 2007, employees whose exposures to hexavalent
chromium exceed a ``respirator threshold'' of 20 [mu]g/m\3\ (measured as
an 8-hour TWA); (3) beginning December 1, 2007, employees whose
exposures to hexavalent chromium exceed a ``respirator threshold'' of
12.5 [mu]g/m\3\ (measured as an 8-hour TWA); (4) employees who are
exposed to hexavalent chromium and request a respirator; (5) any other
employees who are required by the Companies to wear a respirator; and
(6) employees with exposures for which respirators were required under
the previous hexavalent chromium standard (1910.1000) and any other
employees covered by respirator programs in effect on May 30, 2006.
5. Employee information and training. Company employees will be
trained pursuant to the provisions of 29 CFR 1910.1026(l)(2). In
addition, the Companies agree to train employees in the provisions of
this Agreement within sixty (60) days of the Opt-In Date (defined in
paragraph 7 of this Agreement). The training regarding this Agreement
shall be provided in language the employees can understand.
6. Enforcement. Within thirty (30) days of the execution of this
Agreement, OSHA will publish a notice in the Federal Register amending
29 CFR 1910.1026 as follows: (1) A copy of this Agreement will be
attached to the Standard as appendix A; (2) a new paragraph,
1910.1026(n)(4), will be added to the Standard, and will read: ``In
facilities that become parties to the settlement agreement included in
appendix A, engineering controls required by paragraph (f) of this
section shall be implemented no later than December 31, 2008''; and (3)
existing paragraph 1910.1026(n)(3) will be amended to read: ``Except as
provided in (n)(4), for all employers, engineering controls required by
paragraph (f) of this section shall be implemented no later than May 31,
2010.''
7. Opt-In Date for Companies to become parties to this Agreement.
The Federal Register notice described in paragraph 6 of this Agreement
will provide notice of the provisions of this Agreement, and of the
revisions to the Standard described in paragraph 6, and will provide
until November 30, 2006, for eligible facilities to become parties to
this Agreement, and be subject to all of the duties, obligations, and
rights herein. The last date for signing by facilities shall be referred
to as the Opt-In Date. The opt in option will be available on a facility
by facility basis and only to SFIC members and other surface-finishing
and metal-finishing job shop facilities within the jurisdiction of
Federal OSHA. (For purposes of this Agreement, a ``job shop'' is defined
as a facility that sells plating or anodizing services to other
companies.) Moreover, the terms of this Agreement apply only with
respect to the performance of surface-finishing and metal-finishing
operations in those facilities. Although this Agreement applies only to
facilities within the jurisdiction of Federal OSHA, OSHA will encourage
States with OSHA-approved State occupational safety and health plans to
either honor and implement the terms of this Agreement, including the
amendments to the standard described in paragraph 6, or to take an
alternative position, which may include entering into separate
arrangements with surface- and metal-finishing job shop facilities (or
their representatives) in their jurisdiction.
8. Effect on third parties. Nothing in this Agreement constitutes an
admission by SFIC or the Companies that a significant risk of material
health impairment exists for hexavalent chromium justifying a reduction
of the PEL to 5 [mu]g/m\3\. Nor does anything in this Agreement
constitute any other admission by SFIC or the Companies for purposes of
this litigation or future litigation or standards-setting. This
Agreement is not intended to give any rights to any third party except
as expressly provided herein.
9. OSHA inspections. OSHA may do monitoring inspections to assess
compliance with and progress under this Agreement and the Standard, and
nothing in this Agreement limits OSHA's right to conduct inspections at
Companies'' facilities in accordance with the Occupational Safety and
Health Act.
10. Scope of Agreement. The terms of this Agreement apply only in
the circumstances and to the Companies specified herein. In entering
into this Agreement, OSHA is not making any representations regarding
its enforcement policy with respect to either (1) The hexavalent
chromium standard as applied to employers who are not parties to this
Agreement or (2) any other occupational safety or health standards.
11. Effect of invalidation of the Standard. If the Standard is
invalidated, nothing in this Agreement shall prevent the application to
[[Page 141]]
SFIC or the Companies of any PEL that is promulgated by OSHA on remand.
This Agreement would not foreclose SFIC or the Companies from
participating in rulemaking proceedings or otherwise challenging any new
PEL promulgated by OSHA on remand.
12. Withdrawal of Petitions and Interventions. SFIC agrees to move
to withdraw its Petition for Review in the above-captioned case, Case
No. 06-2272, within five (5) working days of the execution of this
Agreement. SFIC further will move to dismiss its motion to intervene in
Case No. 06-1818 and all other challenges simultaneously with its motion
to withdraw in Case No. 06-2272 as Petitioner.
13. Attorneys' fees. Each party agrees to bear its own attorneys'
fees, costs, and other expenses that have been incurred in connection
with SFIC's Petition for Review, SFIC's intervention in HRG's Petition
for Review, and the negotiation of this Agreement up to and including
filing of the motions to dismiss.
14. Support of Agreement. In the event that all or any portion of
this Agreement is challenged in any forum, the signatories below agree
to move to intervene in support of this Agreement.
Agreed to this 25th day of October, 2006.
Baruch A. Fellner,
Counsel for SFIC, Gibson, Dunn & Crutcher LLP, 1050 Connecticut Avenue,
NW., Washington, DC 20036, (202) 955-8500.
Lauren S. Goodman,
Counsel for OSHA, United States Department of Labor, Office of the
Solicitor, 200 Constitution Avenue, NW., Washington, DC 20210, (202)
693-5445.
Scott L. Nelson,
Counsel for HRG and the Steelworkers, Public Citizen Litigation Group,
1600 20th Street, NW., Washington, DC 20009, (202) 588-7724.
Exhibit A
Available Engineering and Work Practice Controls
The Companies agree that work towards the implementation of these
available engineering and work practice controls should not be delayed
to accommodate their completion by December 31, 2008. The Companies are
encouraged to implement from among these controls as soon as
practicable.
1. Parts Transfer Practices
Minimize droplet formation. Instruments akin to
garden hoses are used to rinse off parts coming out of chemical baths.
This causes many small droplets to form, which are easily atomized or
vaporized and contribute to airborne chromium concentration. The
industry is currently developing ways to minimize the formation of small
droplets, dripping, or splashing, possibly by reducing hose pressure.
Minimize air current flow. Strong air currents
across these droplets may contribute to their vaporization, and
therefore minimizing air current flow across the droplets may reduce
airborne hexavalent chromium levels.
Slow part speeds as feasible. The speed at which
parts are pulled out of a chemical tank causes splashing, which adds to
chromium vaporization. By slowing the speed at which parts are taken out
of tanks, splashing and vaporization can be minimized. The feasibility
of this control must be evaluated in light of the negative effect on
productivity.
2. Plating Bath Surface Tension Management and Fume Suppression
Lower surface tension. Lower surface tension in
chemical baths leads to fewer drops forming. Chromium baths currently
have a surface tension of 35 dynes per centimeter. As a comparison,
water has a surface tension of 72 dynes per centimeter. Lowering surface
tension further would lead to reduced airborne hexavalent chromium
levels.
Fume suppressants. Fume suppressants create a
physical barrier between the chemical bath and the air, which prevents
vaporization. Some suppressants, however, may cause pitting or other
metal damage, and therefore their use is not always possible.
3. Facility Air Disturbance Monitoring
Improvement of local exhaust ventilation (LEV)
capture efficiency. The majority of electroplating facilities are not
air-conditioned. As a result, doors are kept open to let in cool air,
but this causes air currents that prevent the LEVs from performing
efficiently. The use of fans has a similar effect. Industry is
researching how to minimize these air currents so that LEVs can perform
as designed. Such methods may include the use of partitions to degrade
air current flow, or checklists that may include location and
positioning of cross drafts, fans, doors, windows, partitions and
process equipment that Companies can use to audit their workplaces in
order to improve their capture efficiency.
4. Technology Enhancements In Lieu of LEV Retrofitting
Eductors. Many chemical baths are currently mixed
via air agitation: Air pipes bubble air into the tank to keep the
chemicals mixed and to prevent them from settling. An adverse effect of
this agitation is that air bubbles escape at the surface of the tank,
resulting in some chromium vaporization. By using eductors (horn-shaped
nozzles) in tanks, the chemicals flow from a pump to create solution
movement below the surface
[[Page 142]]
without the use of air bubbles, and the amount of chromium vaporization
can be significantly reduced.
5. Different Means of Chromium Additions
Liquid Chromium. Dry hexavalent chromium flakes
are occasionally added to tanks, which can generate airborne
particulates of hexavalent chromium. Adding liquid chromium at or near
the surface of a tank would lower airborne chromium levels and reduce
splashing from tanks.
Hydration of flakes before addition. To add
liquid chromium to tanks, the dry flakes must be hydrated. Whether this
process is performed by chemical suppliers that provide plating
solutions to metal finishing companies or by metal finishing companies
that have the necessary experience and equipment, appropriate work
practices such as mixing techniques must be implemented to minimize the
potential airborne levels of hexavalent chromium.
6. Dust Control
Better housekeeping. Chrome dust that comes off
products that are polished or grinded is actually elemental chromium,
not hexavalent chromium, so polishing and grinding contribute little to
airborne hexavalent chromium levels. However, Companies should use good
housekeeping practices, including wet mopping, and wet wipedowns, to
reduce the amount of dust present.
7. Improvement and Maintenance of Existing LEVs
Improvement and maintenance of existing LEVs.
Companies may repair and maintain their current LEVs. Because the final
rule indicates that at least 75 percent of the industry is in compliance
with the PEL with LEVs working at 40% of capacity, increasing LEV
function can materially affect compliance.
8. Other Controls
Other methods. Companies are constantly
determining best work practices and technological controls through
laboratory research and practical experience. Companies will implement
other engineering and work practice controls as necessary and as
practicable to reduce potential hexavalent chromium workplace exposures.
Exhibit B
Workplace Tasks Requiring Respirators Where PEL Is Exceeded
Some well-known and relatively few, discrete tasks related to metal
finishing activities result in potentially higher workplace exposures of
hexavalent chromium. Where the applicable PEL for hexavalent chromium is
exceeded, respirators shall be worn to conduct the following activities:
(1) Hexavalent chromium chemical additions. In order to have the
metal deposited onto the part, hexavalent chromium must be added to the
plating tank periodically. This is a discrete activity that involves the
addition of either a dry flake of hexavalent chromium chemicals or a
liquid solution of hexavalent chromium into the plating tank.
Respirators shall be worn during the period it takes to add the
hexavalent chromium chemical to the tank.
(2) Hexavalent chromium preparation and mixing. Different mixtures
of hexavalent chromium chemicals are needed for different types of
chromium plating processes. For example, hard chromium plating can
require higher concentrations of hexavalent chromium because a thicker
coating and longer plating process may be needed for the critical
product quality and performance. Similarly, different types of
decorative chromium plating processes may need different levels of
hexavalent chromium and other chemicals such as catalysts. These
mixtures can be in the form of dry flakes or liquid solutions. All of
these different hexavalent chromium chemical mixtures are generally
prepared by metal finishing suppliers and distributors. Some metal
finishing companies may also prepare hexavalent chromium solutions from
the dry flakes prior to addition to the plating tanks. Respirators shall
be worn during the period it takes to prepare these hexavalent chromium
mixtures and solutions whether the activity is conducted at a chemical
supplier or a metal finishing company.
(3) Hexavalent chromium tank cleaning. Occasionally, the tanks used
for chromium plating may need to be emptied and cleaned. This process
would involve the draining of the solution and then the removal of any
residues in the tank. Workers cleaning out these tanks may have to enter
the tank or reach into it to remove the residues. Respirators (as well
as other appropriate PPE) shall be worn during the period it takes to
clean the tanks and prepare them for use again.
(4) Hexavalent chromium painting operations. Some metal finishing
operations apply paints with higher concentrations of hexavalent
chromium to a line of parts, particularly for aerospace applications
when a high degree of corrosion protection is needed for critical
product performance. Paints are generally applied in such operations
with some type of spray mechanism or similar dispersion practice. In
some instances, it may be difficult to keep workplace exposures
[[Page 143]]
below the PEL for such paint spraying activities. Respirators shall be
worn during such spray painting operations.
[71 FR 10374, Feb. 28, 2006, as amended at 71 FR 63242, Oct. 30, 2006;
73 FR 75585, Dec. 12, 2008; 75 FR 12686, Mar. 17, 2010; 77 FR 17781,
Mar. 26, 2012]
Sec. 1910.1027 Cadmium.
(a) Scope. This standard applies to all occupational exposures to
cadmium and cadmium compounds, in all forms, and in all industries
covered by the Occupational Safety and Health Act, except the
construction-related industries, which are covered under 29 CFR 1926.63.
(b) Definitions. Action level (AL) is defined as an airborne
concentration of cadmium of 2.5 micrograms per cubic meter of air (2.5
[micro]g/m\3\), calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and
required by work duties to be present in regulated areas or any person
authorized by the OSH Act or regulations issued under it to be in
regulated areas.
Director means the Director of the National Institute for
Occupational Safety and Health (NIOSH), U.S. Department of Health and
Human Services, or designee.
Employee exposure and similar language referring to the air cadmium
level to which an employee is exposed means the exposure to airborne
cadmium that would occur if the employee were not using respiratory
protective equipment.
Final medical determination is the written medical opinion of the
employee's health status by the examining physician under paragraphs
(l)(3)-(12) of this section or, if multiple physician review under
paragraph (l)(13) of this section or the alternative physician
determination under paragraph (l)(14) of this section is invoked, it is
the final, written medical finding, recommendation or determination that
emerges from that process.
High-efficiency particulate air (HEPA) filter means a filter capable
of trapping and retaining at least 99.97 percent of mono-dispersed
particles of 0.3 micrometers in diameter.
Regulated area means an area demarcated by the employer where an
employee's exposure to airborne concentrations of cadmium exceeds, or
can reasonably be expected to exceed the permissible exposure limit
(PEL).
This section means this cadmium standard.
(c) Permissible Exposure Limit (PEL). The employer shall assure that
no employee is exposed to an airborne concentration of cadmium in excess
of five micrograms per cubic meter of air (5 [micro]g/m\3\), calculated
as an eight-hour time-weighted average exposure (TWA).
(d) Exposure monitoring--(1) General. (i) Each employer who has a
workplace or work operation covered by this section shall determine if
any employee may be exposed to cadmium at or above the action level.
(ii) Determinations of employee exposure shall be made from
breathing zone air samples that reflect the monitored employee's
regular, daily 8-hour TWA exposure to cadmium.
(iii) Eight-hour TWA exposures shall be determined for each employee
on the basis of one or more personal breathing zone air samples
reflecting full shift exposure on each shift, for each job
classification, in each work area. Where several employees perform the
same job tasks, in the same job classification, on the same shift, in
the same work area, and the length, duration, and level of cadmium
exposures are similar, an employer may sample a representative fraction
of the employees instead of all employees in order to meet this
requirement. In representative sampling, the employer shall sample the
employee(s) expected to have the highest cadmium exposures.
(2) Specific. (i) Initial monitoring. Except as provided for in
paragraphs (d)(2)(ii) and (d)(2)(iii) of this section, the employer
shall monitor employee exposures and shall base initial determinations
on the monitoring results.
(ii) Where the employer has monitored after September 14, 1991,
under conditions that in all important aspects closely resemble those
currently prevailing and where that monitoring
[[Page 144]]
satisfies all other requirements of this section, including the accuracy
and confidence levels of paragraph (d)(6) of this section, the employer
may rely on such earlier monitoring results to satisfy the requirements
of paragraph (d)(2)(i) of this section.
(iii) Where the employer has objective data, as defined in paragraph
(n)(2) of this section, demonstrating that employee exposure to cadmium
will not exceed the action level under the expected conditions of
processing, use, or handling, the employer may rely upon such data
instead of implementing initial monitoring.
(3) Monitoring Frequency (periodic monitoring). (i) If the initial
monitoring or periodic monitoring reveals employee exposures to be at or
above the action level, the employer shall monitor at a frequency and
pattern needed to represent the levels of exposure of employees and
where exposures are above the PEL to assure the adequacy of respiratory
selection and the effectiveness of engineering and work practice
controls. However, such exposure monitoring shall be performed at least
every six months. The employer, at a minimum, shall continue these semi-
annual measurements unless and until the conditions set out in paragraph
(d)(3)(ii) of this section are met.
(ii) If the initial monitoring or the periodic monitoring indicates
that employee exposures are below the action level and that result is
confirmed by the results of another monitoring taken at least seven days
later, the employer may discontinue the monitoring for those employees
whose exposures are represented by such monitoring.
(4) Additional Monitoring. The employer also shall institute the
exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of
this section whenever there has been a change in the raw materials,
equipment, personnel, work practices, or finished products that may
result in additional employees being exposed to cadmium at or above the
action level or in employees already exposed to cadmium at or above the
action level being exposed above the PEL, or whenever the employer has
any reason to suspect that any other change might result in such further
exposure.
(5) Employee Notification of Monitoring Results. (i) The employer
must, within 15 working days after the receipt of the results of any
monitoring performed under this section, notify each affected employee
of these results either individually in writing or by posting the
results in an appropriate location that is accessible to employees.
(ii) Wherever monitoring results indicate that employee exposure
exceeds the PEL, the employer shall include in the written notice a
statement that the PEL has been exceeded and a description of the
corrective action being taken by the employer to reduce employee
exposure to or below the PEL.
(6) Accuracy of measurement. The employer shall use a method of
monitoring and analysis that has an accuracy of not less than plus or
minus 25 percent (25%), with a confidence level of
95 percent, for airborne concentrations of cadmium at or above the
action level, the permissible exposure limit (PEL), and the separate
engineering control air limit (SECAL).
(e) Regulated areas--(1) Establishment. The employer shall establish
a regulated area wherever an employee's exposure to airborne
concentrations of cadmium is, or can reasonably be expected to be in
excess of the permissible exposure limit (PEL).
(2) Demarcation. Regulated areas shall be demarcated from the rest
of the workplace in any manner that adequately establishes and alerts
employees of the boundaries of the regulated area.
(3) Access. Access to regulated areas shall be limited to authorized
persons.
(4) Provision of respirators. Each person entering a regulated area
shall be supplied with and required to use a respirator, selected in
accordance with paragraph (g)(2) of this section.
(5) Prohibited activities. The employer shall assure that employees
do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in
regulated areas, carry the products associated with these activities
into regulated areas, or store such products in those areas.
(f) Methods of compliance--(1) Compliance hierarchy. (i) Except as
specified in paragraphs (f)(1) (ii), (iii) and (iv) of this section the
employer shall implement engineering and work practice
[[Page 145]]
controls to reduce and maintain employee exposure to cadmium at or below
the PEL, except to the extent that the employer can demonstrate that
such controls are not feasible.
(ii) Except as specified in paragraphs (f)(1) (iii) and (iv) of this
section, in industries where a separate engineering control air limit
(SECAL) has been specified for particular processes (See Table 1 in this
paragraph (f)(1)(ii)), the employer shall implement engineering and work
practice controls to reduce and maintain employee exposure at or below
the SECAL, except to the extent that the employer can demonstrate that
such controls are not feasible.
Table I--Separate Engineering Control Airborne Limits (SECALs) for
Processes in Selected Industries
------------------------------------------------------------------------
SECAL
Industry Process ([micro]g/
m\3\)
------------------------------------------------------------------------
Nickel cadmium battery........... Plate making, plate 50
preparation.
All other processes...... 15
Zinc/Cadmium refining*........... Cadmium refining, 50
casting, melting, oxide
production, sinter plant.
Pigment manufacture.............. Calcine, crushing, 50
milling, blending.
All other processes...... 15
Stabilizers*..................... Cadmium oxide charging, 50
crushing, drying,
blending.
Lead smelting*................... Sinter plant, blast 50
furnace, baghouse, yard
area.
Plating*......................... Mechanical plating....... 15
------------------------------------------------------------------------
*Processes in these industries that are not specified in this table must
achieve the PEL using engineering controls and work practices as
required in f(1)(i).
(iii) The requirement to implement engineering and work practice
controls to achieve the PEL or, where applicable, the SECAL does not
apply where the employer demonstrates the following:
(A) The employee is only intermittently exposed; and
(B) The employee is not exposed above the PEL on 30 or more days per
year (12 consecutive months).
(iv) Wherever engineering and work practice controls are required
and are not sufficient to reduce employee exposure to or below the PEL
or, where applicable, the SECAL, the employer nonetheless shall
implement such controls to reduce exposures to the lowest levels
achievable. The employer shall supplement such controls with respiratory
protection that complies with the requirements of paragraph (g) of this
section and the PEL.
(v) The employer shall not use employee rotation as a method of
compliance.
(2) Compliance program. (i) Where the PEL is exceeded, the employer
shall establish and implement a written compliance program to reduce
employee exposure to or below the PEL by means of engineering and work
practice controls, as required by paragraph (f)(1) of this section. To
the extent that engineering and work practice controls cannot reduce
exposures to or below the PEL, the employer shall include in the written
compliance program the use of appropriate respiratory protection to
achieve compliance with the PEL.
(ii) Written compliance programs shall include at least the
following:
(A) A description of each operation in which cadmium is emitted;
e.g., machinery used, material processed, controls in place, crew size,
employee job responsibilities, operating procedures, and maintenance
practices;
(B) A description of the specific means that will be employed to
achieve compliance, including engineering plans and studies used to
determine methods selected for controlling exposure to cadmium, as well
as, where necessary, the use of appropriate respiratory protection to
achieve the PEL;
(C) A report of the technology considered in meeting the PEL;
(D) Air monitoring data that document the sources of cadmium
emissions;
(E) A detailed schedule for implementation of the program, including
documentation such as copies of purchase orders for equipment,
construction contracts, etc.;
[[Page 146]]
(F) A work practice program that includes items required under
paragraphs (h), (i), and (j) of this section;
(G) A written plan for emergency situations, as specified in
paragraph (h) of this section; and
(H) Other relevant information.
(iii) The written compliance programs shall be reviewed and updated
at least annually, or more often if necessary, to reflect significant
changes in the employer's compliance status.
(iv) Written compliance programs shall be provided upon request for
examination and copying to affected employees, designated employee
representatives as well as to the Assistant Secretary, and the Director.
(3) Mechanical ventilation. (i) When ventilation is used to control
exposure, measurements that demonstrate the effectiveness of the system
in controlling exposure, such as capture velocity, duct velocity, or
static pressure shall be made as necessary to maintain its
effectiveness.
(ii) Measurements of the system's effectiveness in controlling
exposure shall be made as necessary within five working days of any
change in production, process, or control that might result in a
significant increase in employee exposure to cadmium.
(iii) Recirculation of air. If air from exhaust ventilation is
recirculated into the workplace, the system shall have a high efficiency
filter and be monitored to assure effectiveness.
(iv) Procedures shall be developed and implemented to minimize
employee exposure to cadmium when maintenance of ventilation systems and
changing of filters is being conducted.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls when employee exposure levels exceed the PEL.
(ii) Maintenance and repair activities, and brief or intermittent
operations, for which employee exposures exceed the PEL and engineering
and work-practice controls are not feasible or are not required.
(iii) Activities in regulated areas specified in paragraph (e) of
this section.
(iv) Work operations for which the employer has implemented all
feasible engineering and work-practice controls and such controls are
not sufficient to reduce employee exposures to or below the PEL.
(v) Work operations for which an employee is exposed to cadmium at
or above the action level, and the employee requests a respirator.
(vi) Work operations for which an employee is exposed to cadmium
above the PEL and engineering controls are not required by paragraph
(f)(1)(ii) of this section.
(vii) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii)), and (f) through (m), which covers each
employee required by this section to use a respirator.
(ii) No employees must use a respirator if, based on their most
recent medical examination, the examining physician determines that they
will be unable to continue to function normally while using a
respirator. If the physician determines that the employee must be
limited in, or removed from, their current job because of their
inability to use a respirator, the limitation or removal must be in
accordance with paragraphs (l) (11) and (12) of this section.
(iii) If an employee has breathing difficulty during fit testing or
respirator use, the employer must provide the employee with a medical
examination in accordance with paragraph (l)(6)(ii) of this section to
determine if the employee can use a respirator while performing the
required duties.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide employees with full facepiece respirators when they
experience eye irritation.
[[Page 147]]
(C) Provide HEPA filters for powered and non-powered air-purifying
respirators.
(ii) The employer must provide an employee with a powered air-
purifying respirator instead of a negative-pressure respirator when an
employee who is entitled to a respirator chooses to use this type of
respirator and such a respirator provides adequate protection to the
employee.
(h) Emergency situations. The employer shall develop and implement a
written plan for dealing with emergency situations involving substantial
releases of airborne cadmium. The plan shall include provisions for the
use of appropriate respirators and personal protective equipment. In
addition, employees not essential to correcting the emergency situation
shall be restricted from the area and normal operations halted in that
area until the emergency is abated.
(i) Protective work clothing and equipment--(1) Provision and use.
If an employee is exposed to airborne cadmium above the PEL or where
skin or eye irritation is associated with cadmium exposure at any level,
the employer shall provide at no cost to the employee, and assure that
the employee uses, appropriate protective work clothing and equipment
that prevents contamination of the employee and the employee's garments.
Protective work clothing and equipment includes, but is not limited to:
(i) Coveralls or similar full-body work clothing;
(ii) Gloves, head coverings, and boots or foot coverings; and
(iii) Face shields, vented goggles, or other appropriate protective
equipment that complies with 29 CFR 1910.133.
(2) Removal and storage. (i) The employer shall assure that
employees remove all protective clothing and equipment contaminated with
cadmium at the completion of the work shift and do so only in change
rooms provided in accordance with paragraph (j)(1) of this section.
(ii) The employer shall assure that no employee takes cadmium-
contaminated protective clothing or equipment from the workplace, except
for employees authorized to do so for purposes of laundering, cleaning,
maintaining, or disposing of cadmium contaminated protective clothing
and equipment at an appropriate location or facility away from the
workplace.
(iii) The employer shall assure that contaminated protective
clothing and equipment, when removed for laundering, cleaning,
maintenance, or disposal, is placed and stored in sealed, impermeable
bags or other closed, impermeable containers that are designed to
prevent dispersion of cadmium dust.
(iv) The employer shall assure that bags or containers of
contaminated protective clothing and equipment that are to be taken out
of the change rooms or the workplace for laundering, cleaning,
maintenance or disposal shall bear labels in accordance with paragraph
(m)(3) of this section.
(3) Cleaning, replacement, and disposal. (i) The employer shall
provide the protective clothing and equipment required by paragraph
(i)(1) of this section in a clean and dry condition as often as
necessary to maintain its effectiveness, but in any event at least
weekly. The employer is responsible for cleaning and laundering the
protective clothing and equipment required by this paragraph to maintain
its effectiveness and is also responsible for disposing of such clothing
and equipment.
(ii) The employer also is responsible for repairing or replacing
required protective clothing and equipment as needed to maintain its
effectiveness. When rips or tears are detected while an employee is
working they shall be immediately mended, or the worksuit shall be
immediately replaced.
(iii) The employer shall prohibit the removal of cadmium from
protective clothing and equipment by blowing, shaking, or any other
means that disperses cadmium into the air.
(iv) The employer shall assure that any laundering of contaminated
clothing or cleaning of contaminated equipment in the workplace is done
in a manner that prevents the release of airborne cadmium in excess of
the permissible exposure limit prescribed in paragraph (c) of this
section.
(v) The employer shall inform any person who launders or cleans
protective clothing or equipment contaminated with cadmium of the
potentially
[[Page 148]]
harmful effects of exposure to cadmium and that the clothing and
equipment should be laundered or cleaned in a manner to effectively
prevent the release of airborne cadmium in excess of the PEL.
(j) Hygiene areas and practices--(1) General. For employees whose
airborne exposure to cadmium is above the PEL, the employer shall
provide clean change rooms, handwashing facilities, showers, and
lunchroom facilities that comply with 29 CFR 1910.141.
(2) Change rooms. The employer shall assure that change rooms are
equipped with separate storage facilities for street clothes and for
protective clothing and equipment, which are designed to prevent
dispersion of cadmium and contamination of the employee's street
clothes.
(3) Showers and handwashing facilities. (i) The employer shall
assure that employees who are exposed to cadmium above the PEL shower
during the end of the work shift.
(ii) The employer shall assure that employees whose airborne
exposure to cadmium is above the PEL wash their hands and faces prior to
eating, drinking, smoking, chewing tobacco or gum, or applying
cosmetics.
(4) Lunchroom facilities. (i) The employer shall assure that the
lunchroom facilities are readily accessible to employees, that tables
for eating are maintained free of cadmium, and that no employee in a
lunchroom facility is exposed at any time to cadmium at or above a
concentration of 2.5 [micro]g/m\3\.
(ii) The employer shall assure that employees do not enter lunchroom
facilities with protective work clothing or equipment unless surface
cadmium has been removed from the clothing and equipment by HEPA
vacuuming or some other method that removes cadmium dust without
dispersing it.
(k) Housekeeping. (1) All surfaces shall be maintained as free as
practicable of accumulations of cadmium.
(2) All spills and sudden releases of material containing cadmium
shall be cleaned up as soon as possible.
(3) Surfaces contaminated with cadmium shall, wherever possible, be
cleaned by vacuuming or other methods that minimize the likelihood of
cadmium becoming airborne.
(4) HEPA-filtered vacuuming equipment or equally effective
filtration methods shall be used for vacuuming. The equipment shall be
used and emptied in a manner that minimizes the reentry of cadmium into
the workplace.
(5) Shoveling, dry or wet sweeping, and brushing may be used only
where vacuuming or other methods that minimize the likelihood of cadmium
becoming airborne have been tried and found not to be effective.
(6) Compressed air shall not be used to remove cadmium from any
surface unless the compressed air is used in conjunction with a
ventilation system designed to capture the dust cloud created by the
compressed air.
(7) Waste, scrap, debris, bags, containers, personal protective
equipment, and clothing contaminated with cadmium and consigned for
disposal shall be collected and disposed of in sealed impermeable bags
or other closed, impermeable containers. These bags and containers shall
be labeled in accordance with paragraph (m) of this section.
(l) Medical surveillance--(1) General--(i) Scope. (A) Currently
exposed--The employer shall institute a medical surveillance program for
all employees who are or may be exposed to cadmium at or above the
action level unless the employer demonstrates that the employee is not,
and will not be, exposed at or above the action level on 30 or more days
per year (twelve consecutive months); and,
(B) Previously exposed--The employer shall also institute a medical
surveillance program for all employees who prior to the effective date
of this section might previously have been exposed to cadmium at or
above the action level by the employer, unless the employer demonstrates
that the employee did not prior to the effective date of this section
work for the employer in jobs with exposure to cadmium for an aggregated
total of more than 60 months.
(ii) To determine an employee's fitness for using a respirator, the
employer shall provide the limited medical examination specified in
paragraph (l)(6) of this section.
[[Page 149]]
(iii) The employer shall assure that all medical examinations and
procedures required by this standard are performed by or under the
supervision of a licensed physician, who has read and is familiar with
the health effects section of appendix A to this section, the regulatory
text of this section, the protocol for sample handling and laboratory
selection in appendix F to this section, and the questionnaire of
appendix D to this section. These examinations and procedures shall be
provided without cost to the employee and at a time and place that is
reasonable and convenient to employees.
(iv) The employer shall assure that the collecting and handling of
biological samples of cadmium in urine (CdU), cadmium in blood (CdB),
and beta-2 microglobulin in urine ([beta]2-M) taken from
employees under this section is done in a manner that assures their
reliability and that analysis of biological samples of cadmium in urine
(CdU), cadmium in blood (CdB), and beta-2 microglobulin in urine
([beta]2-M) taken from employees under this section is
performed in laboratories with demonstrated proficiency for that
particular analyte. (See appendix F to this section.)
(2) Initial examination. (i) The employer shall provide an initial
(preplacement) examination to all employees covered by the medical
surveillance program required in paragraph (l)(1)(i) of this section.
The examination shall be provided to those employees within 30 days
after initial assignment to a job with exposure to cadmium or no later
than 90 days after the effective date of this section, whichever date is
later.
(ii) The initial (preplacement) medical examination shall include:
(A) A detailed medical and work history, with emphasis on: Past,
present, and anticipated future exposure to cadmium; any history of
renal, cardiovascular, respiratory, hematopoietic, reproductive, and/or
musculo-skeletal system dysfunction; current usage of medication with
potential nephrotoxic side-effects; and smoking history and current
status; and
(B) Biological monitoring that includes the following tests:
(1) Cadmium in urine (CdU), standardized to grams of creatinine (g/
Cr);
(2) Beta-2 microglobulin in urine ([beta]2-M),
standardized to grams of creatinine (g/Cr), with pH specified, as
described in appendix F to this section; and
(3) Cadmium in blood (CdB), standardized to liters of whole blood
(lwb).
(iii) Recent Examination: An initial examination is not required to
be provided if adequate records show that the employee has been examined
in accordance with the requirements of paragraph (l)(2)(ii) of this
section within the past 12 months. In that case, such records shall be
maintained as part of the employee's medical record and the prior exam
shall be treated as if it were an initial examination for the purposes
of paragraphs (l)(3) and (4) of this section.
(3) Actions triggered by initial biological monitoring: (i) If the
results of the initial biological monitoring tests show the employee's
CdU level to be at or below 3 [micro]g/g Cr, [beta]2-M level
to be at or below 300 [micro]g/g Cr and CdB level to be at or below 5
[micro]g/lwb, then:
(A) For currently exposed employees, who are subject to medical
surveillance under paragraph (l)(1)(i)(A) of this section, the employer
shall provide the minimum level of periodic medical surveillance in
accordance with the requirements in paragraph (l)(4)(i) of this section;
and
(B) For previously exposed employees, who are subject to medical
surveillance under paragraph (l)(1)(i)(B) of this section, the employer
shall provide biological monitoring for CdU, [beta]2-M, and
CdB one year after the initial biological monitoring and then the
employer shall comply with the requirements of paragraph (l)(4)(v) of
this section.
(ii) For all employees who are subject to medical surveillance under
paragraph (l)(1)(i) of this section, if the results of the initial
biological monitoring tests show the level of CdU to exceed 3 [micro]g/g
Cr, the level of [beta]2-M to exceed 300 [micro]g/g Cr, or
the level of CdB to exceed 5 [micro]g/lwb, the employer shall:
(A) Within two weeks after receipt of biological monitoring results,
reassess the employee's occupational exposure to cadmium as follows:
[[Page 150]]
(1) Reassess the employee's work practices and personal hygiene;
(2) Reevaluate the employee's respirator use, if any, and the
respirator program;
(3) Review the hygiene facilities;
(4) Reevaluate the maintenance and effectiveness of the relevant
engineering controls;
(5) Assess the employee's smoking history and status;
(B) Within 30 days after the exposure reassessment, specified in
paragraph (l)(3)(ii)(A) of this section, take reasonable steps to
correct any deficiencies found in the reassessment that may be
responsible for the employee's excess exposure to cadmium; and,
(C) Within 90 days after receipt of biological monitoring results,
provide a full medical examination to the employee in accordance with
the requirements of paragraph (l)(4)(ii) of this section. After
completing the medical examination, the examining physician shall
determine in a written medical opinion whether to medically remove the
employee. If the physician determines that medical removal is not
necessary, then until the employee's CdU level falls to or below 3
[micro]g/g Cr, [beta]2-M level falls to or below 300
[micro]g/g Cr and CdB level falls to or below 5 [micro]g/lwb, the
employer shall:
(1) Provide biological monitoring in accordance with paragraph
(l)(2)(ii)(B) of this section on a semiannual basis; and
(2) Provide annual medical examinations in accordance with paragraph
(l)(4)(ii) of this section.
(iii) For all employees who are subject to medical surveillance
under paragraph (l)(1)(i) of this section, if the results of the initial
biological monitoring tests show the level of CdU to be in excess of 15
[micro]g/g Cr, or the level of CdB to be in excess of 15 [micro]g/lwb,
or the level of [beta]2-M to be in excess of 1,500 [micro]g/g
Cr, the employer shall comply with the requirements of paragraphs
(l)(3)(ii)(A)-(B) of this section. Within 90 days after receipt of
biological monitoring results, the employer shall provide a full medical
examination to the employee in accordance with the requirements of
paragraph (l)(4)(ii) of this section. After completing the medical
examination, the examining physician shall determine in a written
medical opinion whether to medically remove the employee. However, if
the initial biological monitoring results and the biological monitoring
results obtained during the medical examination both show that: CdU
exceeds 15 [micro]g/g Cr; or CdB exceeds 15 [micro]g/lwb; or
[beta]2-M exceeds 1500 [micro]g/g Cr, and in addition CdU
exceeds 3 [micro]g/g Cr or CdB exceeds 5 [micro]g/liter of whole blood,
then the physician shall medically remove the employee from exposure to
cadmium at or above the action level. If the second set of biological
monitoring results obtained during the medical examination does not show
that a mandatory removal trigger level has been exceeded, then the
employee is not required to be removed by the mandatory provisions of
this paragraph. If the employee is not required to be removed by the
mandatory provisions of this paragraph or by the physician's
determination, then until the employee's CdU level falls to or below 3
[micro]g/g Cr, [beta]2-M level falls to or below 300
[micro]g/g Cr and CdB level falls to or below 5 [micro]g/lwb, the
employer shall:
(A) Periodically reassess the employee's occupational exposure to
cadmium;
(B) Provide biological monitoring in accordance with paragraph
(l)(2)(ii)(B) of this section on a quarterly basis; and
(C) Provide semiannual medical examinations in accordance with
paragraph (l)(4)(ii) of this section.
(iv) For all employees to whom medical surveillance is provided,
beginning on January 1, 1999, and in lieu of paragraphs (l)(3)(i)-(iii)
of this section:
(A) If the results of the initial biological monitoring tests show
the employee's CdU level to be at or below 3 [micro]g/g Cr,
[beta]2-M level to be at or below 300 [micro]g/g Cr and CdB
level to be at or below 5 [micro]g/lwb, then for currently exposed
employees, the employer shall comply with the requirements of paragraph
(l)(3)(i)(A) of this section, and for previously exposed employees, the
employer shall comply with the requirements of paragraph (l)(3)(i)(B) of
this section;
(B) If the results of the initial biological monitoring tests show
the level of CdU to exceed 3 [micro]g/g Cr, the level of
[beta]2-M to exceed 300 [micro]g/g Cr, or the level of CdB to
exceed 5 [micro]g/lwb, the employer
[[Page 151]]
shall comply with the requirements of paragraphs (l)(3)(ii)(A)-(C) of
this section; and,
(C) If the results of the initial biological monitoring tests show
the level of CdU to be in excess of 7 [micro]g/g Cr, or the level of CdB
to be in excess of 10 [micro]g/lwb, or the level of [beta]2-M
to be in excess of 750 [micro]g/g Cr, the employer shall: Comply with
the requirements of paragraphs (l)(3)(ii)(A)-(B) of this section; and,
within 90 days after receipt of biological monitoring results, provide a
full medical examination to the employee in accordance with the
requirements of paragraph (l)(4)(ii) of this section. After completing
the medical examination, the examining physician shall determine in a
written medical opinion whether to medically remove the employee.
However, if the initial biological monitoring results and the biological
monitoring results obtained during the medical examination both show
that: CdU exceeds 7 [micro]g/g Cr; or CdB exceeds 10 [micro]g/lwb; or
[beta]2-M exceeds 750 [micro]g/g Cr, and in addition CdU
exceeds 3 [micro]g/g Cr or CdB exceeds 5 [micro]g/liter of whole blood,
then the physician shall medically remove the employee from exposure to
cadmium at or above the action level. If the second set of biological
monitoring results obtained during the medical examination does not show
that a mandatory removal trigger level has been exceeded, then the
employee is not required to be removed by the mandatory provisions of
this paragraph. If the employee is not required to be removed by the
mandatory provisions of this paragraph or by the physician's
determination, then until the employee's CdU level falls to or below 3
[micro]g/g Cr, [beta]2-M level falls to or below 300
[micro]g/g Cr and CdB level falls to or below 5 [micro]g/lwb, the
employer shall: periodically reassess the employee's occupational
exposure to cadmium; provide biological monitoring in accordance with
paragraph (l)(2)(ii)(B) of this section on a quarterly basis; and
provide semiannual medical examinations in accordance with paragraph
(l)(4)(ii) of this section.
(4) Periodic medical surveillance. (i) For each employee who is
covered under paragraph (l)(1)(i)(A) of this section, the employer shall
provide at least the minimum level of periodic medical surveillance,
which consists of periodic medical examinations and periodic biological
monitoring. A periodic medical examination shall be provided within one
year after the initial examination required by paragraph (l)(2) of this
section and thereafter at least biennially. Biological sampling shall be
provided at least annually, either as part of a periodic medical
examination or separately as periodic biological monitoring.
(ii) The periodic medical examination shall include:
(A) A detailed medical and work history, or update thereof, with
emphasis on: Past, present and anticipated future exposure to cadmium;
smoking history and current status; reproductive history; current use of
medications with potential nephrotoxic side-effects; any history of
renal, cardiovascular, respiratory, hematopoietic, and/or musculo-
skeletal system dysfunction; and as part of the medical and work
history, for employees who wear respirators, questions 3-11 and 25-32 in
appendix D to this section;
(B) A complete physical examination with emphasis on: Blood
pressure, the respiratory system, and the urinary system;
(C) A 14 inch by 17 inch, or a reasonably standard sized posterior-
anterior chest X-ray (after the initial X-ray, the frequency of chest X-
rays is to be determined by the examining physician);
(D) Pulmonary function tests, including forced vital capacity (FVC)
and forced expiratory volume at 1 second (FEV1);
(E) Biological monitoring, as required in paragraph (l)(2)(ii)(B) of
this section;
(F) Blood analysis, in addition to the analysis required under
paragraph (l)(2)(ii)(B) of this section, including blood urea nitrogen,
complete blood count, and serum creatinine;
(G) Urinalysis, in addition to the analysis required under paragraph
(l)(2)(ii)(B) of this section, including the determination of albumin,
glucose, and total and low molecular weight proteins;
(H) For males over 40 years old, prostate palpation, or other at
least as effective diagnostic test(s); and
[[Page 152]]
(I) Any additional tests deemed appropriate by the examining
physician.
(iii) Periodic biological monitoring shall be provided in accordance
with paragraph (l)(2)(ii)(B) of this section.
(iv) If the results of periodic biological monitoring or the results
of biological monitoring performed as part of the periodic medical
examination show the level of the employee's CdU, [beta]2-M,
or CdB to be in excess of the levels specified in paragraphs (l)(3)(ii)
or (iii); or, beginning on January 1, 1999, in excess of the levels
specified in paragraphs (l)(3)(ii) or (iv) of this section, the employer
shall take the appropriate actions specified in paragraphs (l)(3)(ii)-
(iv) of this section.
(v) For previously exposed employees under paragraph (l)(1)(i)(B) of
this section:
(A) If the employee's levels of CdU did not exceed 3 [micro]g/g Cr,
CdB did not exceed 5 [micro]g/lwb, and [beta]2-M did not
exceed 300 [micro]g/g Cr in the initial biological monitoring tests, and
if the results of the followup biological monitoring required by
paragraph (l)(3)(i)(B) of this section one year after the initial
examination confirm the previous results, the employer may discontinue
all periodic medical surveillance for that employee.
(B) If the initial biological monitoring results for CdU, CdB, or
[beta]2-M were in excess of the levels specified in paragraph
(l)(3)(i) of this section, but subsequent biological monitoring results
required by paragraph (l)(3)(ii)-(iv) of this section show that the
employee's CdU levels no longer exceed 3 [micro]g/g Cr, CdB levels no
longer exceed 5 [micro]g/lwb, and [beta]2-M levels no longer
exceed 300 [micro]g/g Cr, the employer shall provide biological
monitoring for CdU, CdB, and [beta]2-M one year after these
most recent biological monitoring results. If the results of the
followup biological monitoring, specified in this paragraph, confirm the
previous results, the employer may discontinue all periodic medical
surveillance for that employee.
(C) However, if the results of the follow-up tests specified in
paragraph (l)(4)(v)(A) or (B) of this section indicate that the level of
the employee's CdU, [beta]2-M, or CdB exceeds these same
levels, the employer is required to provide annual medical examinations
in accordance with the provisions of paragraph (l)(4)(ii) of this
section until the results of biological monitoring are consistently
below these levels or the examining physician determines in a written
medical opinion that further medical surveillance is not required to
protect the employee's health.
(vi) A routine, biennial medical examination is not required to be
provided in accordance with paragraphs (l)(3)(i) and (l)(4) of this
section if adequate medical records show that the employee has been
examined in accordance with the requirements of paragraph (l)(4)(ii) of
this section within the past 12 months. In that case, such records shall
be maintained by the employer as part of the employee's medical record,
and the next routine, periodic medical examination shall be made
available to the employee within two years of the previous examination.
(5) Actions triggered by medical examinations. (i) If the results of
a medical examination carried out in accordance with this section
indicate any laboratory or clinical finding consistent with cadmium
toxicity that does not require employer action under paragraph (l)(2),
(3) or (4) of this section, the employer, within 30 days, shall reassess
the employee's occupational exposure to cadmium and take the following
corrective action until the physician determines they are no longer
necessary:
(A) Periodically reassess: The employee's work practices and
personal hygiene; the employee's respirator use, if any; the employee's
smoking history and status; the respiratory protection program; the
hygiene facilities; and the maintenance and effectiveness of the
relevant engineering controls;
(B) Within 30 days after the reassessment, take all reasonable steps
to correct the deficiencies found in the reassessment that may be
responsible for the employee's excess exposure to cadmium;
(C) Provide semiannual medical reexaminations to evaluate the
abnormal clinical sign(s) of cadmium toxicity until the results are
normal or the employee is medically removed; and
(D) Where the results of tests for total proteins in urine are
abnormal,
[[Page 153]]
provide a more detailed medical evaluation of the toxic effects of
cadmium on the employee's renal system.
(6) Examination for respirator use. (i) To determine an employee's
fitness for respirator use, the employer shall provide a medical
examination that includes the elements specified in paragraph
(l)(6)(i)(A)-(D) of this section. This examination shall be provided
prior to the employee's being assigned to a job that requires the use of
a respirator or no later than 90 days after this section goes into
effect, whichever date is later, to any employee without a medical
examination within the preceding 12 months that satisfies the
requirements of this paragraph.
(A) A detailed medical and work history, or update thereof, with
emphasis on: Past exposure to cadmium; smoking history and current
status; any history of renal, cardiovascular, respiratory,
hematopoietic, and/or musculoskeletal system dysfunction; a description
of the job for which the respirator is required; and questions 3-11 and
25-32 in appendix D to this section;
(B) A blood pressure test;
(C) Biological monitoring of the employee's levels of CdU, CdB and
[beta]2-M in accordance with the requirements of paragraph
(l)(2)(ii)(B) of this section, unless such results already have been
obtained within the previous 12 months; and
(D) Any other test or procedure that the examining physician deems
appropriate.
(ii) After reviewing all the information obtained from the medical
examination required in paragraph (l)(6)(i) of this section, the
physician shall determine whether the employee is fit to wear a
respirator.
(iii) Whenever an employee has exhibited difficulty in breathing
during a respirator fit test or during use of a respirator, the
employer, as soon as possible, shall provide the employee with a
periodic medical examination in accordance with paragraph (l)(4)(ii) of
this section to determine the employee's fitness to wear a respirator.
(iv) Where the results of the examination required under paragraph
(l)(6)(i), (ii), or (iii) of this section are abnormal, medical
limitation or prohibition of respirator use shall be considered. If the
employee is allowed to wear a respirator, the employee's ability to
continue to do so shall be periodically evaluated by a physician.
(7) Emergency examinations. (i) In addition to the medical
surveillance required in paragraphs (l)(2)-(6) of this section, the
employer shall provide a medical examination as soon as possible to any
employee who may have been acutely exposed to cadmium because of an
emergency.
(ii) The examination shall include the requirements of paragraph
(l)(4)(ii) of this section, with emphasis on the respiratory system,
other organ systems considered appropriate by the examining physician,
and symptoms of acute overexposure, as identified in paragraphs II
(B)(1)-(2) and IV of appendix A to this section.
(8) Termination of employment examination. (i) At termination of
employment, the employer shall provide a medical examination in
accordance with paragraph (l)(4)(ii) of this section, including a chest
X-ray, to any employee to whom at any prior time the employer was
required to provide medical surveillance under paragraphs (l)(1)(i) or
(l)(7) of this section. However, if the last examination satisfied the
requirements of paragraph (l)(4)(ii) of this section and was less than
six months prior to the date of termination, no further examination is
required unless otherwise specified in paragraphs (l)(3) or (l)(5) of
this section;
(ii) However, for employees covered by paragraph (l)(1)(i)(B) of
this section, if the employer has discontinued all periodic medical
surveillance under paragraph (l)(4)(v) of this section, no termination
of employment medical examination is required.
(9) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and appendices;
(ii) A description of the affected employee's former, current, and
anticipated duties as they relate to the employee's occupational
exposure to cadmium;
[[Page 154]]
(iii) The employee's former, current, and anticipated future levels
of occupational exposure to cadmium;
(iv) A description of any personal protective equipment, including
respirators, used or to be used by the employee, including when and for
how long the employee has used that equipment; and
(v) relevant results of previous biological monitoring and medical
examinations.
(10) Physician's written medical opinion. (i) The employer shall
promptly obtain a written, medical opinion from the examining physician
for each medical examination performed on each employee. This written
opinion shall contain:
(A) The physician's diagnosis for the employee;
(B) The physician's opinion as to whether the employee has any
detected medical condition(s) that would place the employee at increased
risk of material impairment to health from further exposure to cadmium,
including any indications of potential cadmium toxicity;
(C) The results of any biological or other testing or related
evaluations that directly assess the employee's absorption of cadmium;
(D) Any recommended removal from, or limitation on the activities or
duties of the employee or on the employee's use of personal protective
equipment, such as respirators;
(E) A statement that the physician has clearly and carefully
explained to the employee the results of the medical examination,
including all biological monitoring results and any medical conditions
related to cadmium exposure that require further evaluation or
treatment, and any limitation on the employee's diet or use of
medications.
(ii) The employer promptly shall obtain a copy of the results of any
biological monitoring provided by an employer to an employee
independently of a medical examination under paragraphs (l)(2) and
(l)(4) of this section, and, in lieu of a written medical opinion, an
explanation sheet explaining those results.
(iii) The employer shall instruct the physician not to reveal orally
or in the written medical opinion given to the employer specific
findings or diagnoses unrelated to occupational exposure to cadmium.
(11) Medical Removal Protection (MRP)--(i) General. (A) The employer
shall temporarily remove an employee from work where there is excess
exposure to cadmium on each occasion that medical removal is required
under paragraph (l)(3), (l)(4), or (l)(6) of this section and on each
occasion that a physician determines in a written medical opinion that
the employee should be removed from such exposure. The physician's
determination may be based on biological monitoring results, inability
to wear a respirator, evidence of illness, other signs or symptoms of
cadmium-related dysfunction or disease, or any other reason deemed
medically sufficient by the physician.
(B) The employer shall medically remove an employee in accordance
with paragraph (l)(11) of this section regardless of whether at the time
of removal a job is available into which the removed employee may be
transferred.
(C) Whenever an employee is medically removed under paragraph
(l)(11) of this section, the employer shall transfer the removed
employee to a job where the exposure to cadmium is within the
permissible levels specified in that paragraph as soon as one becomes
available.
(D) For any employee who is medically removed under the provisions
of paragraph (l)(11)(i) of this section, the employer shall provide
follow-up biological monitoring in accordance with (l)(2)(ii)(B) of this
section at least every three months and follow-up medical examinations
semi-annually at least every six months until in a written medical
opinion the examining physician determines that either the employee may
be returned to his/her former job status as specified under paragraph
(l)(11)(iv)-(v) of this section or the employee must be permanently
removed from excess cadmium exposure.
(E) The employer may not return an employee who has been medically
removed for any reason to his/her former job status until a physician
determines in a written medical opinion that continued medical removal
is no longer
[[Page 155]]
necessary to protect the employee's health.
(ii) Where an employee is found unfit to wear a respirator under
paragraph (l)(6)(ii) of this section, the employer shall remove the
employee from work where exposure to cadmium is above the PEL.
(iii) Where removal is based on any reason other than the employee's
inability to wear a respirator, the employer shall remove the employee
from work where exposure to cadmium is at or above the action level.
(iv) Except as specified in paragraph (l)(11)(v) of this section, no
employee who was removed because his/her level of CdU, CdB and/or
[beta]2-M exceeded the medical removal trigger levels in
paragraph (l)(3) or (l)(4) of this section may be returned to work with
exposure to cadmium at or above the action level until the employee's
levels of CdU fall to or below 3 [micro]g/g Cr, CdB falls to or below 5
[micro]g/lwb, and [beta]2-M falls to or below 300 [micro]g/g
Cr.
(v) However, when in the examining physician's opinion continued
exposure to cadmium will not pose an increased risk to the employee's
health and there are special circumstances that make continued medical
removal an inappropriate remedy, the physician shall fully discuss these
matters with the employee, and then in a written determination may
return a worker to his/her former job status despite what would
otherwise be unacceptably high biological monitoring results.
Thereafter, the returned employee shall continue to be provided with
medical surveillance as if he/she were still on medical removal until
the employee's levels of CdU fall to or below 3 [micro]g/g Cr, CdB falls
to or below 5 [micro]g/lwb, and [beta]2-M falls to or below
300 [micro]g/g Cr.
(vi) Where an employer, although not required by paragraph
(l)(11)(i)-(iii) of this section to do so, removes an employee from
exposure to cadmium or otherwise places limitations on an employee due
to the effects of cadmium exposure on the employee's medical condition,
the employer shall provide the same medical removal protection benefits
to that employee under paragraph (l)(12) of this section as would have
been provided had the removal been required under paragraph (l)(11)(i)-
(iii) of this section.
(12) Medical Removal Protection Benefits (MRPB). (i) The employer
shall provide MRPB for up to a maximum of 18 months to an employee each
time and while the employee is temporarily medically removed under
paragraph (l)(11) of this section.
(ii) For purposes of this section, the requirement that the employer
provide MRPB means that the employer shall maintain the total normal
earnings, seniority, and all other employee rights and benefits of the
removed employee, including the employee's right to his/her former job
status, as if the employee had not been removed from the employee's job
or otherwise medically limited.
(iii) Where, after 18 months on medical removal because of elevated
biological monitoring results, the employee's monitoring results have
not declined to a low enough level to permit the employee to be returned
to his/her former job status:
(A) The employer shall make available to the employee a medical
examination pursuant to this section in order to obtain a final medical
determination as to whether the employee may be returned to his/her
former job status or must be permanently removed from excess cadmium
exposure; and
(B) The employer shall assure that the final medical determination
indicates whether the employee may be returned to his/her former job
status and what steps, if any, should be taken to protect the employee's
health.
(iv) The employer may condition the provision of MRPB upon the
employee's participation in medical surveillance provided in accordance
with this section.
(13) Multiple physician review. (i) If the employer selects the
initial physician to conduct any medical examination or consultation
provided to an employee under this section, the employee may designate a
second physician to:
(A) Review any findings, determinations, or recommendations of the
initial physician; and
(B) Conduct such examinations, consultations, and laboratory tests
as the
[[Page 156]]
second physician deems necessary to facilitate this review.
(ii) The employer shall promptly notify an employee of the right to
seek a second medical opinion after each occasion that an initial
physician provided by the employer conducts a medical examination or
consultation pursuant to this section. The employer may condition its
participation in, and payment for, multiple physician review upon the
employee doing the following within fifteen (15) days after receipt of
this notice, or receipt of the initial physician's written opinion,
whichever is later:
(A) Informing the employer that he or she intends to seek a medical
opinion; and
(B) Initiating steps to make an appointment with a second physician.
(iii) If the findings, determinations, or recommendations of the
second physician differ from those of the initial physician, then the
employer and the employee shall assure that efforts are made for the two
physicians to resolve any disagreement.
(iv) If the two physicians have been unable to quickly resolve their
disagreement, then the employer and the employee, through their
respective physicians, shall designate a third physician to:
(A) Review any findings, determinations, or recommendations of the
other two physicians; and
(B) Conduct such examinations, consultations, laboratory tests, and
discussions with the other two physicians as the third physician deems
necessary to resolve the disagreement among them.
(v) The employer shall act consistently with the findings,
determinations, and recommendations of the third physician, unless the
employer and the employee reach an agreement that is consistent with the
recommendations of at least one of the other two physicians.
(14) Alternate physician determination. The employer and an employee
or designated employee representative may agree upon the use of any
alternate form of physician determination in lieu of the multiple
physician review provided by paragraph (l)(13) of this section, so long
as the alternative is expeditious and at least as protective of the
employee.
(15) Information the employer must provide the employee. (i) The
employer shall provide a copy of the physician's written medical opinion
to the examined employee within two weeks after receipt thereof.
(ii) The employer shall provide the employee with a copy of the
employee's biological monitoring results and an explanation sheet
explaining the results within two weeks after receipt thereof.
(iii) Within 30 days after a request by an employee, the employer
shall provide the employee with the information the employer is required
to provide the examining physician under paragraph (l)(9) of this
section.
(16) Reporting. In addition to other medical events that are
required to be reported on the OSHA Form No. 200, the employer shall
report any abnormal condition or disorder caused by occupational
exposure to cadmium associated with employment as specified in Chapter
(V)(E) of the Reporting Guidelines for Occupational Injuries and
Illnesses.
(m) Communication of cadmium hazards to employees--(1) Hazard
communication.--general. (i) Chemical manufacturers, importers,
distributors and employers shall comply with all requirements of the
Hazard Communication Standard (HCS) (Sec. 1910.1200) for cadmium.
(ii) In classifying the hazards of cadmium at least the following
hazards are to be addressed: Cancer; lung effects; kidney effects; and
acute toxicity effects.
(iii) Employers shall include cadmium in the hazard communication
program established to comply with the HCS (Sec. 1910.1200). Employers
shall ensure that each employee has access to labels on containers of
cadmium and to safety data sheets, and is trained in accordance with the
requirements of HCS and paragraph (m)(4) of this section.
(2) Warning signs. (i) Warning signs shall be provided and displayed
in regulated areas. In addition, warning signs shall be posted at all
approaches to regulated areas so that an employee may read the signs and
take necessary
[[Page 157]]
protective steps before entering the area.
(ii) Warning signs required by paragraph (m)(2)(i) of this section
shall bear the following legend:
DANGER
CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(iii) The employer shall ensure that signs required by this
paragraph (m)(2) are illuminated, cleaned, and maintained as necessary
so that the legend is readily visible.
(iv) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (m)(2)(ii) of this section:
DANGER
CADMIUM
CANCER HAZARD
CAN CAUSE LUNG AND KIDNEY DISEASE
AUTHORIZED PERSONNEL ONLY
RESPIRATORS REQUIRED IN THIS AREA
(3) Warning labels. (i) Shipping and storage containers containing
cadmium or cadmium compounds shall bear appropriate warning labels, as
specified in paragraph (m)(1) of this section.
(ii) The warning labels for containers of contaminated protective
clothing, equipment, waste, scrap, or debris shall include at least the
following information:
DANGER
CONTAINS CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
AVOID CREATING DUST
(iii) Prior to June 1, 2015, employers may include the following
information on shipping and storage containers containing cadmium,
cadmium compounds, or cadmium contaminated clothing, equipment, waste,
scrap, or debris in lieu of the labeling requirements specified in
paragraphs (m)(1)(i) and (m)(3)(ii) of this section:
DANGER
CONTAINS CADMIUM
CANCER HAZARD
AVOID CREATING DUST
CAN CAUSE LUNG AND KIDNEY DISEASE
(iv) Where feasible, installed cadmium products shall have a visible
label or other indication that cadmium is present.
(4) Employee information and training. (i) The employer shall train
each employee who is potentially exposed to cadmium in accordance with
the requirements of this section. The employer shall institute a
training program, ensure employee participation in the program, and
maintain a record of the contents of such program.
(ii) Training shall be provided prior to or at the time of initial
assignment to a job involving potential exposure to cadmium and at least
annually thereafter.
(iii) The employer shall make the training program understandable to
the employee and shall assure that each employee is informed of the
following:
(A) The health hazards associated with cadmium exposure, with
special attention to the information incorporated in appendix A to this
section;
(B) The quantity, location, manner of use, release, and storage of
cadmium in the workplace and the specific nature of operations that
could result in exposure to cadmium, especially exposures above the PEL;
(C) The engineering controls and work practices associated with the
employee's job assignment;
(D) The measures employees can take to protect themselves from
exposure to cadmium, including modification of such habits as smoking
and personal hygiene, and specific procedures the employer has
implemented to protect employees from exposure to cadmium such as
appropriate work practices, emergency procedures, and the provision of
personal protective equipment;
(E) The purpose, proper selection, fitting, proper use, and
limitations of respirators and protective clothing;
(F) The purpose and a description of the medical surveillance
program required by paragraph (l) of this section;
(G) The contents of this section and its appendices; and
(H) The employee's rights of access to records underSec.
1910.1020(e) and (g).
(iv) Additional access to information and training program and
materials.
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(A) The employer shall make a copy of this section and its
appendices readily available without cost to all affected employees and
shall provide a copy if requested.
(B) The employer shall provide to the Assistant Secretary or the
Director, upon request, all materials relating to the employee
information and the training program.
(n) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and keep an accurate record of all air monitoring for cadmium
in the workplace.
(ii) This record shall include at least the following information:
(A) The monitoring date, duration, and results in terms of an 8-hour
TWA of each sample taken;
(B) The name, social security number, and job classification of the
employees monitored and of all other employees whose exposures the
monitoring is intended to represent;
(C) A description of the sampling and analytical methods used and
evidence of their accuracy;
(D) The type of respiratory protective device, if any, worn by the
monitored employee;
(E) A notation of any other conditions that might have affected the
monitoring results.
(iii) The employer shall maintain this record for at least thirty
(30) years, in accordance with 29 CFR 1910.1020.
(2) Objective data for exemption from requirement for initial
monitoring. (i) For purposes of this section, objective data are
information demonstrating that a particular product or material
containing cadmium or a specific process, operation, or activity
involving cadmium cannot release dust or fumes in concentrations at or
above the action level even under the worst-case release conditions.
Objective data can be obtained from an industry-wide study or from
laboratory product test results from manufacturers of cadmium-containing
products or materials. The data the employer uses from an industry-wide
survey must be obtained under workplace conditions closely resembling
the processes, types of material, control methods, work practices and
environmental conditions in the employer's current operations.
(ii) The employer shall establish and maintain a record of the
objective data for at least 30 years.
(3) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee covered by medical
surveillance under paragraph (l)(1)(i) of this section.
(ii) The record shall include at least the following information
about the employee:
(A) Name, social security number, and description of the duties;
(B) A copy of the physician's written opinions and an explanation
sheet for biological monitoring results;
(C) A copy of the medical history, and the results of any physical
examination and all test results that are required to be provided by
this section, including biological tests, X-rays, pulmonary function
tests, etc., or that have been obtained to further evaluate any
condition that might be related to cadmium exposure;
(D) The employee's medical symptoms that might be related to
exposure to cadmium; and
(E) A copy of the information provided to the physician as required
by paragraph (l)(9)(ii)-(v) of this section.
(iii) The employer shall assure that this record is maintained for
the duration of employment plus thirty (30) years, in accordance with 29
CFR 1910.1020.
(4) Availability. (i) Except as otherwise provided for in this
section, access to all records required to be maintained by paragraphs
(n)(1) through (3) of this section shall be in accordance with the
provisions of 29 CFR 1910.1020.
(ii) Within 15 days after a request, the employer shall make an
employee's medical records required to be kept by paragraph (n)(3) of
this section available for examination and copying to the subject
employee, to designated representatives, to anyone having the specific
written consent of the subject employee, and after the employee's death
or incapacitation, to the employee's family members.
(6) Transfer of records. Whenever an employer ceases to do business
and
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there is no successor employer to receive and retain records for the
prescribed period or the employer intends to dispose of any records
required to be preserved for at least 30 years, the employer shall
comply with the requirements concerning transfer of records set forth in
29 CFR 1910.1020 (h).
(o) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their designated
representatives an opportunity to observe any monitoring of employee
exposure to cadmium.
(2) Observation procedures. When observation of monitoring requires
entry into an area where the use of protective clothing or equipment is
required, the employer shall provide the observer with that clothing and
equipment and shall assure that the observer uses such clothing and
equipment and complies with all other applicable safety and health
procedures.
(p) Dates--(1) Effective date. This section shall become effective
December 14, 1992.
(2) Start-up dates. All obligations of this section commence on the
effective date except as follows:
(i) Exposure monitoring. Except for small businesses (nineteen (19)
or fewer employees), initial monitoring required by paragraph (d)(2) of
this section shall be completed as soon as possible and in any event no
later than 60 days after the effective date of this standard. For small
businesses, initial monitoring required by paragraph (d)(2) of this
section shall be completed as soon as possible and in any event no later
than 120 days after the effective date of this standard.
(ii) Regulated areas. Except for small business, defined under
paragraph (p)(2)(i) of this section, regulated areas required to be
established by paragraph (e) of this section shall be set up as soon as
possible after the results of exposure monitoring are known and in any
event no later than 90 days after the effective date of this section.
For small businesses, regulated areas required to be established by
paragraph (e) of this section shall be set up as soon as possible after
the results of exposure monitoring are known and in any event no later
than 150 days after the effective date of this section.
(iii) Respiratory protection. Except for small businesses, defined
under paragraph (p)(2)(i) of this section, respiratory protection
required by paragraph (g) of this section shall be provided as soon as
possible and in any event no later than 90 days after the effective date
of this section. For small businesses, respiratory protection required
by paragraph (g) of this section shall be provided as soon as possible
and in any event no later than 150 days after the effective date of this
section.
(iv) Compliance program. Written compliance programs required by
paragraph (f)(2) of this section shall be completed and available for
inspection and copying as soon as possible and in any event no later
than 1 year after the effective date of this section.
(v) Methods of compliance. The engineering controls required by
paragraph (f)(1) of this section shall be implemented as soon as
possible and in any event no later than two (2) years after the
effective date of this section. Work practice controls shall be
implemented as soon as possible. Work practice controls that are
directly related to engineering controls to be implemented in accordance
with the compliance plan shall be implemented as soon as possible after
such engineering controls are implemented.
(vi) Hygiene and lunchroom facilities. (A) Handwashing facilities,
permanent or temporary, shall be provided in accordance with 29 CFR
1910.141 (d)(1) and (2) as soon as possible and in any event no later
than 60 days after the effective date of this section.
(B) Change rooms, showers, and lunchroom facilities shall be
completed as soon as possible and in any event no later than 1 year
after the effective date of this section.
(vii) Employee information and training. Except for small
businesses, defined under paragraph (p)(2)(i) of this section, employee
information and training required by paragraph (m)(4) of this section
shall be provided as soon as possible and in any event no later than 90
days after the effective date of this standard. For small businesses,
employee information and training required by paragraph (m)(4) of this
standard shall be provided as soon as possible and in any event no later
than
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180 days after the effective date of this standard.
(viii) Medical surveillance. Except for small businesses, defined
under paragraph (p)(2)(i) of this section, initial medical examinations
required by paragraph (l) of this section shall be provided as soon as
possible and in any event no later than 90 days after the effective date
of this standard. For small businesses, initial medical examinations
required by paragraph (l) of this section shall be provided as soon as
possible and in any event no later than 180 days after the effective
date of this standard.
(q) Appendices. Except where portions of appendices A, B, D, E, and
F to this section are expressly incorporated in requirements of this
section, these appendices are purely informational and are not intended
to create any additional obligations not otherwise imposed or to detract
from any existing obligations.
Appendix A toSec. 1910.1027--Substance Safety Data Sheet
Cadmium
I. Substance Identification
A. Substance: Cadmium.
B. 8-Hour, Time-weighted-average, Permissible Exposure Limit (TWA
PEL):
1. TWA PEL: Five micrograms of cadmium per cubic meter of air 5
[micro]g/m\3\, time-weighted average (TWA) for an 8-hour workday.
C. Appearance: Cadmium metal--soft, blue-white, malleable, lustrous
metal or grayish-white powder. Some cadmium compounds may also appear as
a brown, yellow, or red powdery substance.
II. Health Hazard Data
A. Routes of Exposure. Cadmium can cause local skin or eye
irritation. Cadmium can affect your health if you inhale it or if you
swallow it.
B. Effects of Overexposure.
1. Short-term (acute) exposure: Cadmium is much more dangerous by
inhalation than by ingestion. High exposures to cadmium that may be
immediately dangerous to life or health occur in jobs where workers
handle large quantities of cadmium dust or fume; heat cadmium-containing
compounds or cadmium-coated surfaces; weld with cadmium solders or cut
cadmium-containing materials such as bolts.
2. Severe exposure may occur before symptoms appear. Early symptoms
may include mild irritation of the upper respiratory tract, a sensation
of constriction of the throat, a metallic taste and/or a cough. A period
of 1-10 hours may precede the onset of rapidly progressing shortness of
breath, chest pain, and flu-like symptoms with weakness, fever,
headache, chills, sweating and muscular pain. Acute pulmonary edema
usually develops within 24 hours and reaches a maximum by three days. If
death from asphyxia does not occur, symptoms may resolve within a week.
3. Long-term (chronic) exposure. Repeated or long-term exposure to
cadmium, even at relatively low concentrations, may result in kidney
damage and an increased risk of cancer of the lung and of the prostate.
C. Emergency First Aid Procedures.
1. Eye exposure: Direct contact may cause redness or pain. Wash eyes
immediately with large amounts of water, lifting the upper and lower
eyelids. Get medical attention immediately.
2. Skin exposure: Direct contact may result in irritation. Remove
contaminated clothing and shoes immediately. Wash affected area with
soap or mild detergent and large amounts of water. Get medical attention
immediately.
3. Ingestion: Ingestion may result in vomiting, abdominal pain,
nausea, diarrhea, headache and sore throat. Treatment for symptoms must
be administered by medical personnel. Under no circumstances should the
employer allow any person whom he retains, employs, supervises or
controls to engage in therapeutic chelation. Such treatment is likely to
translocate cadmium from pulmonary or other tissue to renal tissue. Get
medical attention immediately.
4. Inhalation: If large amounts of cadmium are inhaled, the exposed
person must be moved to fresh air at once. If breathing has stopped,
perform cardiopulmonary resuscitation. Administer oxygen if available.
Keep the affected person warm and at rest. Get medical attention
immediately.
5. Rescue: Move the affected person from the hazardous exposure. If
the exposed person has been overcome, attempt rescue only after
notifying at least one other person of the emergency and putting into
effect established emergency procedures. Do not become a casualty
yourself. Understand your emergency rescue procedures and know the
location of the emergency equipment before the need arises.
III. Employee Information
A. Protective Clothing and Equipment.
1. Respirators: You may be required to wear a respirator for non-
routine activities; in emergencies; while your employer is in the
process of reducing cadmium exposures through engineering controls; and
where engineering controls are not feasible. If respirators are worn in
the future, they must have a joint Mine Safety and Health Administration
(MSHA) and National Institute for
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Occupational Safety and Health (NIOSH) label of approval. Cadmium does
not have a detectable odor except at levels well above the permissible
exposure limits. If you can smell cadmium while wearing a respirator,
proceed immediately to fresh air. If you experience difficulty breathing
while wearing a respirator, tell your employer.
2. Protective Clothing: You may be required to wear impermeable
clothing, gloves, foot gear, a face shield, or other appropriate
protective clothing to prevent skin contact with cadmium. Where
protective clothing is required, your employer must provide clean
garments to you as necessary to assure that the clothing protects you
adequately. The employer must replace or repair protective clothing that
has become torn or otherwise damaged.
3. Eye Protection: You may be required to wear splash-proof or dust
resistant goggles to prevent eye contact with cadmium.
B. Employer Requirements.
1. Medical: If you are exposed to cadmium at or above the action
level, your employer is required to provide a medical examination,
laboratory tests and a medical history according to the medical
surveillance provisions under paragraph (1) of this standard. (See
summary chart and tables in this appendix A.) These tests shall be
provided without cost to you. In addition, if you are accidentally
exposed to cadmium under conditions known or suspected to constitute
toxic exposure to cadmium, your employer is required to make special
tests available to you.
2. Access to Records: All medical records are kept strictly
confidential. You or your representative are entitled to see the records
of measurements of your exposure to cadmium. Your medical examination
records can be furnished to your personal physician or designated
representative upon request by you to your employer.
3. Observation of Monitoring: Your employer is required to perform
measurements that are representative of your exposure to cadmium and you
or your designated representative are entitled to observe the monitoring
procedure. You are entitled to observe the steps taken in the
measurement procedure, and to record the results obtained. When the
monitoring procedure is taking place in an area where respirators or
personal protective clothing and equipment are required to be worn, you
or your representative must also be provided with, and must wear the
protective clothing and equipment.
C. Employee Requirements--You will not be able to smoke, eat, drink,
chew gum or tobacco, or apply cosmetics while working with cadmium in
regulated areas. You will also not be able to carry or store tobacco
products, gum, food, drinks or cosmetics in regulated areas because
these products easily become contaminated with cadmium from the
workplace and can therefore create another source of unnecessary cadmium
exposure.
Some workers will have to change out of work clothes and shower at
the end of the day, as part of their workday, in order to wash cadmium
from skin and hair. Handwashing and cadmium-free eating facilities shall
be provided by the employer and proper hygiene should always be
performed before eating. It is also recommended that you do not smoke or
use tobacco products, because among other things, they naturally contain
cadmium. For further information, read the labeling on such products.
IV. Physician Information
A. Introduction. The medical surveillance provisions of paragraph
(1) generally are aimed at accomplishing three main interrelated
purposes: First, identifying employees at higher risk of adverse health
effects from excess, chronic exposure to cadmium; second, preventing
cadmium-induced disease; and third, detecting and minimizing existing
cadmium-induced disease. The core of medical surveillance in this
standard is the early and periodic monitoring of the employee's
biological indicators of: (a) Recent exposure to cadmium; (b) cadmium
body burden; and (c) potential and actual kidney damage associated with
exposure to cadmium.
The main adverse health effects associated with cadmium overexposure
are lung cancer and kidney dysfunction. It is not yet known how to
adequately biologically monitor human beings to specifically prevent
cadmium-induced lung cancer. By contrast, the kidney can be monitored to
provide prevention and early detection of cadmium-induced kidney damage.
Since, for non-carcinogenic effects, the kidney is considered the
primary target organ of chronic exposure to cadmium, the medical
surveillance provisions of this standard effectively focus on cadmium-
induced kidney disease. Within that focus, the aim, where possible, is
to prevent the onset of such disease and, where necessary, to minimize
such disease as may already exist. The by-products of successful
prevention of kidney disease are anticipated to be the reduction and
prevention of other cadmium-induced diseases.
B. Health Effects. The major health effects associated with cadmium
overexposure are described below.
1. Kidney: The most prevalent non-malignant disease observed among
workers chronically exposed to cadmium is kidney dysfunction. Initially,
such dysfunction is manifested as proteinuria. The proteinuria
associated with cadmium exposure is most commonly characterized by
excretion of low-molecular weight proteins (15,000 to 40,000 MW)
accompanied by loss of electrolytes, uric acid, calcium, amino acids,
and phosphate. The compounds commonly excreted include:
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beta-2-microglobulin ([beta]2-M), retinol binding protein
(RBP), immunoglobulin light chains, and lysozyme. Excretion of low
molecular weight proteins are characteristic of damage to the proximal
tubules of the kidney (Iwao et al., 1980).
It has also been observed that exposure to cadmium may lead to
urinary excretion of high-molecular weight proteins such as albumin,
immunoglobulin G, and glycoproteins (Ex. 29). Excretion of high-
molecular weight proteins is typically indicative of damage to the
glomeruli of the kidney. Bernard et al., (1979) suggest that damage to
the glomeruli and damage to the proximal tubules of the kidney may both
be linked to cadmium exposure but they may occur independently of each
other.
Several studies indicate that the onset of low-molecular weight
proteinuria is a sign of irreversible kidney damage (Friberg et al.,
1974; Roels et al., 1982; Piscator 1984; Elinder et al., 1985; Smith et
al., 1986). Above specific levels of [beta]2-M associated
with cadmium exposure it is unlikely that [beta]2-M levels
return to normal even when cadmium exposure is eliminated by removal of
the individual from the cadmium work environment (Friberg, Ex. 29,
1990).
Some studies indicate that such proteinuria may be progressive;
levels of [beta]2-M observed in the urine increase with time
even after cadmium exposure has ceased. See, for example, Elinder et
al., 1985. Such observations, however, are not universal, and it has
been suggested that studies in which proteinuria has not been observed
to progress may not have tracked patients for a sufficiently long time
interval (Jarup, Ex. 8-661).
When cadmium exposure continues after the onset of proteinuria,
chronic nephrotoxicity may occur (Friberg, Ex. 29). Uremia results from
the inability of the glomerulus to adequately filter blood. This leads
to severe disturbance of electrolyte concentrations and may lead to
various clinical complications including kidney stones (L-140-50).
After prolonged exposure to cadmium, glomerular proteinuria,
glucosuria, aminoaciduria, phosphaturia, and hypercalciuria may develop
(Exs. 8-86, 4-28, 14-18). Phosphate, calcium, glucose, and amino acids
are essential to life, and under normal conditions, their excretion
should be regulated by the kidney. Once low molecular weight proteinuria
has developed, these elements dissipate from the human body. Loss of
glomerular function may also occur, manifested by decreased glomerular
filtration rate and increased serum creatinine. Severe cadmium-induced
renal damage may eventually develop into chronic renal failure and
uremia (Ex. 55).
Studies in which animals are chronically exposed to cadmium confirm
the renal effects observed in humans (Friberg et al., 1986). Animal
studies also confirm problems with calcium metabolism and related
skeletal effects which have been observed among humans exposed to
cadmium in addition to the renal effects. Other effects commonly
reported in chronic animal studies include anemia, changes in liver
morphology, immunosuppression and hypertension. Some of these effects
may be associated with co-factors. Hypertension, for example, appears to
be associated with diet as well as cadmium exposure. Animals injected
with cadmium have also shown testicular necrosis (Ex. 8-86B).
2. Biological Markers
It is universally recognized that the best measures of cadmium
exposures and its effects are measurements of cadmium in biological
fluids, especially urine and blood. Of the two, CdU is conventionally
used to determine body burden of cadmium in workers without kidney
disease. CdB is conventionally used to monitor for recent exposure to
cadmium. In addition, levels of CdU and CdB historically have been used
to predict the percent of the population likely to develop kidney
disease (Thun et al., Ex. L-140-50; WHO, Ex. 8-674; ACGIH, Exs. 8-667,
140-50).
The third biological parameter upon which OSHA relies for medical
surveillance is Beta-2-microglobulin in urine ([beta]2-M), a
low molecular weight protein. Excess [beta]2-M has been
widely accepted by physicians and scientists as a reliable indicator of
functional damage to the proximal tubule of the kidney (Exs. 8-447, 144-
3-C, 4-47, L-140-45, 19-43-A).
Excess [beta]2-M is found when the proximal tubules can
no longer reabsorb this protein in a normal manner. This failure of the
proximal tubules is an early stage of a kind of kidney disease that
commonly occurs among workers with excessive cadmium exposure. Used in
conjunction with biological test results indicating abnormal levels of
CdU and CdB, the finding of excess [beta]2-M can establish
for an examining physician that any existing kidney disease is probably
cadmium-related (Trs. 6/6/90, pp. 82-86, 122, 134). The upper limits of
normal levels for cadmium in urine and cadmium in blood are 3 [micro]g
Cd/gram creatinine in urine and 5 [micro]gCd/liter whole blood,
respectively. These levels were derived from broad-based population
studies.
Three issues confront the physicians in the use of
[beta]2-M as a marker of kidney dysfunction and material
impairment. First, there are a few other causes of elevated levels of
[beta]2-M not related to cadmium exposures, some of which may
be rather common diseases and some of which are serious diseases (e.g.,
myeloma or transient flu, Exs. 29 and 8-086). These can be medically
evaluated as alternative causes (Friberg, Ex. 29). Also, there are other
factors that can cause [beta]2-M to degrade so that low
levels would result in
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workers with tubular dysfunction. For example, regarding the degradation
of [beta]2-M, workers with acidic urine (pH<6) might have
[beta]2-M levels that are within the ``normal'' range when in
fact kidney dysfunction has occurred (Ex. L-140-1) and the low molecular
weight proteins are degraded in acid urine. Thus, it is very important
that the pH of urine be measured, that urine samples be buffered as
necessary (See appendix F.), and that urine samples be handled
correctly, i.e., measure the pH of freshly voided urine samples, then if
necessary, buffer to pH6 (or above for shipping purposes),
measure pH again and then, perhaps, freeze the sample for storage and
shipping. (See also appendix F.) Second, there is debate over the
pathological significance of proteinuria, however, most world experts
believe that [beta]2-M levels greater than 300 [micro]g/g Cr
are abnormal (Elinder, Ex. 55, Friberg, Ex. 29). Such levels signify
kidney dysfunction that constitutes material impairment of health.
Finally, detection of [beta]2-M at low levels has often been
considered difficult, however, many laboratories have the capability of
detecting excess [beta]2-M using simple kits, such as the
Phadebas Delphia test, that are accurate to levels of 100 [micro]g
[beta]2-M/g Cr U (Ex. L-140-1).
Specific recommendations for ways to measure [beta]2-M
and proper handling of urine samples to prevent degradation of
[beta]2-M have been addressed by OSHA in appendix F, in the
section on laboratory standardization. All biological samples must be
analyzed in a laboratory that is proficient in the analysis of that
particular analyte, under paragraph (l)(1)(iv). (See appendix F).
Specifically, under paragraph (l)(1)(iv), the employer is to assure that
the collecting and handling of biological samples of cadmium in urine
(CdU), cadmium in blood (CdB), and beta-2 microglobulin in urine
([beta]2-M) taken from employees is collected in a manner
that assures reliability. The employer must also assure that analysis of
biological samples of cadmium in urine (CdU), cadmium in blood (CdB),
and beta-2 microglobulin in urine ([beta]2-M) taken from
employees is performed in laboratories with demonstrated proficiency for
that particular analyte. (See appendix F.)
3. Lung and Prostate Cancer
The primary sites for cadmium-associated cancer appear to be the
lung and the prostate (L-140-50). Evidence for an association between
cancer and cadmium exposure derives from both epidemiological studies
and animal experiments. Mortality from prostate cancer associated with
cadmium is slightly elevated in several industrial cohorts, but the
number of cases is small and there is not clear dose-response
relationship. More substantive evidence exists for lung cancer.
The major epidemiological study of lung cancer was conducted by Thun
et al., (Ex. 4-68). Adequate data on cadmium exposures were available to
allow evaluation of dose-response relationships between cadmium exposure
and lung cancer. A statistically significant excess of lung cancer
attributed to cadmium exposure was observed in this study even when
confounding variables such as co-exposure to arsenic and smoking habits
were taken into consideration (Ex. L-140-50).
The primary evidence for quantifying a link between lung cancer and
cadmium exposure from animal studies derives from two rat bioassay
studies; one by Takenaka et al., (1983), which is a study of cadmium
chloride and a second study by Oldiges and Glaser (1990) of four cadmium
compounds.
Based on the above cited studies, the U.S. Environmental Protection
Agency (EPA) classified cadmium as ``B1'', a probable human carcinogen,
in 1985 (Ex. 4-4). The International Agency for Research on Cancer
(IARC) in 1987 also recommended that cadmium be listed as ``2A'', a
probable human carcinogen (Ex. 4-15). The American Conference of
Governmental Industrial Hygienists (ACGIH) has recently recommended that
cadmium be labeled as a carcinogen. Since 1984, NIOSH has concluded that
cadmium is possibly a human carcinogen and has recommended that
exposures be controlled to the lowest level feasible.
4. Non-carcinogenic Effects
Acute pneumonitis occurs 10 to 24 hours after initial acute
inhalation of high levels of cadmium fumes with symptoms such as fever
and chest pain (Exs. 30, 8-86B). In extreme exposure cases pulmonary
edema may develop and cause death several days after exposure. Little
actual exposure measurement data is available on the level of airborne
cadmium exposure that causes such immediate adverse lung effects,
nonetheless, it is reasonable to believe a cadmium concentration of
approximately 1 mg/m\3\ over an eight hour period is ``immediately
dangerous'' (55 FR 4052, ANSI; Ex. 8-86B).
In addition to acute lung effects and chronic renal effects, long
term exposure to cadmium may cause other severe effects on the
respiratory system. Reduced pulmonary function and chronic lung disease
indicative of emphysema have been observed in workers who have had
prolonged exposure to cadmium dust or fumes (Exs. 4-29, 4-22, 4-42, 4-
50, 4-63). In a study of workers conducted by Kazantzis et al., a
statistically significant excess of worker deaths due to chronic
bronchitis was found, which in his opinion was directly related to high
cadmium exposures of 1 mg/m\3\ or more (Tr. 6/8/90, pp. 156-157).
Cadmium need not be respirable to constitute a hazard. Inspirable
cadmium particles that are too large to be respirable but small enough
to enter the tracheobronchial region of the lung can lead to
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bronchoconstriction, chronic pulmonary disease, and cancer of that
portion of the lung. All of these diseases have been associated with
occupational exposure to cadmium (Ex. 8-86B). Particles that are
constrained by their size to the extra-thoracic regions of the
respiratory system such as the nose and maxillary sinuses can be
swallowed through mucocillary clearance and be absorbed into the body
(ACGIH, Ex. 8-692). The impaction of these particles in the upper
airways can lead to anosmia, or loss of sense of smell, which is an
early indication of overexposure among workers exposed to heavy metals.
This condition is commonly reported among cadmium-exposed workers (Ex.
8-86-B).
C. Medical Surveillance
In general, the main provisions of the medical surveillance section
of the standard, under paragraphs (l)(1)-(17) of the regulatory text,
are as follows:
1. Workers exposed above the action level are covered;
2. Workers with intermittent exposures are not covered;
3. Past workers who are covered receive biological monitoring for at
least one year;
4. Initial examinations include a medical questionnaire and
biological monitoring of cadmium in blood (CdB), cadmium in urine (CdU),
and Beta-2-microglobulin in urine ([beta]2-M);
5. Biological monitoring of these three analytes is performed at
least annually; full medical examinations are performed biennially;
6. Until five years from the effective date of the standard, medical
removal is required when CdU is greater than 15 [micro]g/gram creatinine
(g Cr), or CdB is greater than 15 [micro]g/liter whole blood (lwb), or
[beta]2-M is greater than 1500 [micro]g/g Cr, and CdB is
greater than 5 [micro]g/lwb or CdU is greater than 3 [micro]g/g Cr;
7. Beginning five years after the standard is in effect, medical
removal triggers will be reduced;
8. Medical removal protection benefits are to be provided for up to
18 months;
9. Limited initial medical examinations are required for respirator
usage;
10. Major provisions are fully described under section (l) of the
regulatory text; they are outlined here as follows:
A. Eligibility
B. Biological monitoring
C. Actions triggered by levels of CdU, CdB, and [beta]2-M
(See Summary Charts and Tables in Attachment-1.)
D. Periodic medical surveillance
E. Actions triggered by periodic medical surveillance (See appendix
A Summary Chart and Tables in Attachment-1.)
F. Respirator usage
G. Emergency medical examinations
H. Termination examination
I. Information to physician
J. Physician's medical opinion
K. Medical removal protection
L. Medical removal protection benefits
M. Multiple physician review
N. Alternate physician review
O. Information employer gives to employee
P. Recordkeeping
Q. Reporting on OSHA form 200
11. The above mentioned summary of the medical surveillance
provisions, the summary chart, and tables for the actions triggered at
different levels of CdU, CdB and [beta]2-M (in appendix A
Attachment-1) are included only for the purpose of facilitating
understanding of the provisions of paragraphs (l)(3) of the final
cadmium standard. The summary of the provisions, the summary chart, and
the tables do not add to or reduce the requirements in paragraph (l)(3).
D. Recommendations to Physicians
1. It is strongly recommended that patients with tubular proteinuria
are counseled on: The hazards of smoking; avoidance of nephrotoxins and
certain prescriptions and over-the-counter medications that may
exacerbate kidney symptoms; how to control diabetes and/or blood
pressure; proper hydration, diet, and exercise (Ex. 19-2). A list of
prominent or common nephrotoxins is attached. (See appendix A
Attachment-2.)
2. DO NOT CHELATE; KNOW WHICH DRUGS ARE NEPHROTOXINS OR ARE
ASSOCIATED WITH NEPHRITIS.
3. The gravity of cadmium-induced renal damage is compounded by the
fact there is no medical treatment to prevent or reduce the accumulation
of cadmium in the kidney (Ex. 8-619). Dr. Friberg, a leading world
expert on cadmium toxicity, indicated in 1992, that there is no form of
chelating agent that could be used without substantial risk. He stated
that tubular proteinuria has to be treated in the same way as other
kidney disorders (Ex. 29).
4. After the results of a workers' biological monitoring or medical
examination are received the employer is required to provide an
information sheet to the patient, briefly explaining the significance of
the results. (See Attachment 3 of this appendix A.)
5. For additional information the physician is referred to the
following additional resources:
a. The physician can always obtain a copy of the preamble, with its
full discussion of the health effects, from OSHA's Computerized
Information System (OCIS).
b. The Docket Officer maintains a record of the rulemaking. The
Cadmium Docket (H-057A), is located at 200 Constitution Ave. NW., room
N-2625, Washington, DC 20210; telephone: 202-219-7894.
c. The following articles and exhibits in particular from that
docket (H-057A):
[[Page 165]]
------------------------------------------------------------------------
Exhibit number Author and paper title
------------------------------------------------------------------------
8-447................ Lauwerys et. al., Guide for physicians, ``Health
Maintenance of Workers Exposed to Cadmium,''
published by the Cadmium Council.
4-67................. Takenaka, S., H. Oldiges, H. Konig, D.
Hochrainer, G. Oberdorster. ``Carcinogenicity of
Cadmium Chloride Aerosols in Wistar Rats''. JNCI
70:367-373, 1983. (32)
4-68................. Thun, M.J., T.M. Schnoor, A.B. Smith, W.E.
Halperin, R.A. Lemen. ``Mortality Among a Cohort
of U.S. Cadmium Production Workers--An Update.''
JNCI 74(2):325-33, 1985. (8)
4-25................. Elinder, C.G., Kjellstrom, T., Hogstedt, C., et
al., ``Cancer Mortality of Cadmium Workers.''
Brit. J. Ind. Med. 42:651-655, 1985. (14)
4-26................. Ellis, K.J. et al., ``Critical Concentrations of
Cadmium in Human Renal Cortex: Dose Effect
Studies to Cadmium Smelter Workers.'' J.
Toxicol. Environ. Health 7:691-703, 1981. (76)
4-27................. Ellis, K.J., S.H. Cohn and T.J. Smith. ``Cadmium
Inhalation Exposure Estimates: Their
Significance with Respect to Kidney and Liver
Cadmium Burden.'' J. Toxicol. Environ. Health
15:173-187, 1985.
4-28................. Falck, F.Y., Jr., Fine, L.J., Smith, R.G.,
McClatchey, K.D., Annesley, T., England, B., and
Schork, A.M. ``Occupational Cadmium Exposure and
Renal Status.'' Am. J. Ind. Med. 4:541, 1983.
(64)
8-86A................ Friberg, L., C.G. Elinder, et al., ``Cadmium and
Health a Toxicological and Epidemiological
Appraisal, Volume I, Exposure, Dose, and
Metabolism.'' CRC Press, Inc., Boca Raton, FL,
1986. (Available from the OSHA Technical Data
Center)
8-86B................ Friberg, L., C.G. Elinder, et al., ``Cadmium and
Health: A Toxicological and Epidemiological
Appraisal, Volume II, Effects and Response.''
CRC Press, Inc., Boca Raton, FL, 1986.
(Available from the OSHA Technical Data Center)
L-140-45............. Elinder, C.G., ``Cancer Mortality of Cadmium
Workers'', Brit. J. Ind. Med., 42, 651-655,
1985.
L-140-50............. Thun, M., Elinder, C.G., Friberg, L, ``Scientific
Basis for an Occupational Standard for Cadmium,
Am. J. Ind. Med., 20; 629-642, 1991.
------------------------------------------------------------------------
V. Information Sheet
The information sheet (appendix A Attachment-3.) or an equally
explanatory one should be provided to you after any biological
monitoring results are reviewed by the physician, or where applicable,
after any medical examination.
Attachment 1--Appendix A Summary Chart and Tables A and B of Actions
Triggered by Biological Monitoring
Appendix A Summary Chart: Section (1)(3) Medical Surveillance
Categorizing Biological Monitoring Results
(A) Biological monitoring results categories are set forth in
appendix A Table A for the periods ending December 31, 1998 and for the
period beginning January 1, 1999.
(B) The results of the biological monitoring for the initial medical
exam and the subsequent exams shall determine an employee's biological
monitoring result category.
Actions Triggered by Biological Monitoring
(A)
(i) The actions triggered by biological monitoring for an employee
are set forth in appendix A Table B.
(ii) The biological monitoring results for each employee under
section (1)(3) shall determine the actions required for that employee.
That is, for any employee in biological monitoring category C, the
employer will perform all of the actions for which there is an X in
column C of appendix A Table B.
(iii) An employee is assigned the alphabetical category (``A'' being
the lowest) depending upon the test results of the three biological
markers.
(iv) An employee is assigned category A if monitoring results for
all three biological markers fall at or below the levels indicated in
the table listed for category A.
(v) An employee is assigned category B if any monitoring result for
any of the three biological markers fall within the range of levels
indicated in the table listed for category B, providing no result
exceeds the levels listed for category B.
(vi) An employee is assigned category C if any monitoring result for
any of the three biological markers are above the levels listed for
category C.
(B) The user of appendix A Tables A and B should know that these
tables are provided only to facilitate understanding of the relevant
provisions of paragraph (l)(3) of this section. appendix A Tables A and
B are not meant to add to or subtract from the requirements of those
provisions.
Appendix A Table A--Categorization of Biological Monitoring Results
Applicable Through 1998 Only
----------------------------------------------------------------------------------------------------------------
Monitoring result categories
Biological marker ----------------------------------------------
A B C
----------------------------------------------------------------------------------------------------------------
Cadmium in urine (CdU) ([micro]g/g creatinine)................... <=3 3 and <=15 15
[beta]2-microglobulin ([beta]2-M) ([micro]g/g creatinine)........ <=300 300 and 1500*
[[Page 166]]
Cadmium in blood (CdB) ([micro]g/liter whole blood).............. <=5 5 and <=15 15
----------------------------------------------------------------------------------------------------------------
* If an employee's [beta]2-M levels are above 1,500 [micro]g/g creatinine, in order for mandatory medical
removal to be required (See appendix A Table B.), either the employee's CdU level must also be >3 [micro]g/g
creatinine or CdB level must also be >5 [micro]g/liter whole blood.
Applicable Beginning January 1, 1999
----------------------------------------------------------------------------------------------------------------
Monitoring result categories
Biological marker ----------------------------------------------
A B C
----------------------------------------------------------------------------------------------------------------
Cadmium in urine (CdU) ([micro]g/g creatinine)................... <=3 3 and <=7 7
[beta]2-microglobulin ([beta]2-M) ([micro]g/g creatinine)........ <=300 300 and 750*
Cadmium in blood (CdB) ([micro]g/liter whole blood).............. <=5 5 and <=10 10
----------------------------------------------------------------------------------------------------------------
* If an employee's [beta]2-M levels are above 750 [micro]g/g creatinine, in order for mandatory medical removal
to be required (See appendix A Table B.), either the employee's CdU level must also be >3 [micro]g/g
creatinine or CdB level must also be >5 [micro]g/liter whole blood.
Appendix A Table B--Actions Determined by Biological Monitoring
This table presents the actions required based on the monitoring
result in appendix A Table A. Each item is a separate requirement in
citing non-compliance. For example, a medical examination within 90 days
for an employee in category B is separate from the requirement to
administer a periodic medical examination for category B employees on an
annual basis.
------------------------------------------------------------------------
Monitoring result category
Required actions -----------------------------------------
A \1\ B \1\ C \1\
------------------------------------------------------------------------
(1) Biological monitoring:
(a) Annual................ X
(b) Semiannual............ ............ X
(c) Quarterly............. ............ ............ X
(2) Medical examination:
(a) Biennial.............. X
(b) Annual................ ............ X
(c) Semiannual............ ............ ............ X
(d) Within 90 days........ ............ X X
(3) Assess within two weeks:
(a) Excess cadmium ............ X X
exposure.
(b) Work practices........ ............ X X
(c) Personal hygiene...... ............ X X
(d) Respirator usage...... ............ X X
(e) Smoking history....... ............ X X
(f) Hygiene facilities.... ............ X X
(g) Engineering controls.. ............ X X
(h) Correct within 30 days ............ X X
(i) Periodically assess ............ ............ X
exposures.
(4) Discretionary medical ............ X X
removal.
(5) Mandatory medical removal. ............ ............ X \2\
------------------------------------------------------------------------
\1\ For all employees covered by medical surveillance exclusively
because of exposures prior to the effective date of this standard, if
they are in Category A, the employer shall follow the requirements of
paragraphs (l)(3)(i)(B) and (l)(4)(v)(A). If they are in Category B or
C, the employer shall follow the requirements of paragraphs
(l)(4)(v)(B)-(C).
\2\ See footnote appendix A Table A.
Appendix A--Attachment 2--List of Medications
A list of the more common medications that a physician, and the
employee, may wish to review is likely to include some of the following:
(1) Anticonvulsants: Paramethadione, phenytoin, trimethadone; (2)
antihypertensive drugs: Captopril, methyldopa; (3) antimicrobials:
Aminoglycosides, amphotericin B, cephalosporins, ethambutol; (4)
antineoplastic agents: Cisplatin, methotrexate, mitomycin-C,
nitrosoureas, radiation; (4) sulfonamide diuretics: Acetazolamide,
chlorthalidone, furosemide, thiazides; (5) halogenated alkanes,
hydrocarbons, and solvents that may occur in
[[Page 167]]
some settings: Carbon tetrachloride, ethylene glycol, toluene; iodinated
radiographic contrast media; nonsteroidal anti-inflammatory drugs; and,
(7) other miscellaneous compounds: Acetominophen, allopurinol,
amphetamines, azathioprine, cimetidine, cyclosporine, lithium,
methoxyflurane, methysergide, D-penicillamine, phenacetin, phenendione.
A list of drugs associated with acute interstitial nephritis includes:
(1) Antimicrobial drugs: Cephalosporins, chloramphenicol, colistin,
erythromycin, ethambutol, isoniazid, para-aminosalicylic acid,
penicillins, polymyxin B, rifampin, sulfonamides, tetracyclines, and
vancomycin; (2) other miscellaneous drugs: Allopurinol, antipyrene,
azathioprine, captopril, cimetidine, clofibrate, methyldopa,
phenindione, phenylpropanolamine, phenytoin, probenecid, sulfinpyrazone,
sulfonamid diuretics, triamterene; and, (3) metals: Bismuth, gold.
This list have been derived from commonly available medical
textbooks (e.g., Ex. 14-18). The list has been included merely to
facilitate the physician's, employer's, and employee's understanding.
The list does not represent an official OSHA opinion or policy regarding
the use of these medications for particular employees. The use of such
medications should be under physician discretion.
Attachment 3--Biological Monitoring and Medical Examination Results
Employee________________________________________________________________
Testing Date____________________________________________________________
Cadmium in Urine ------ [micro]g/g Cr--Normal Levels: <=3 [micro]g/g
Cr.
Cadmium in Blood ------ [micro]g/lwb--Normal Levels: <=5 [micro]g/
lwb.
Beta-2-microglobulin in Urine ------ [micro]g/g Cr--Normal Levels:
<=300 [micro]g/g Cr.
Physical Examination Results: N/A ------ Satisfactory ------
Unsatisfactory ------ (see physician again).
Physician's Review of Pulmonary Function Test: N/A ------ Normal --
---- Abnormal ------.
Next biological monitoring or medical examination scheduled for_________
The biological monitoring program has been designed for three main
purposes: 1) to identify employees at risk of adverse health effects
from excess, chronic exposure to cadmium; 2) to prevent cadmium-induced
disease(s); and 3) to detect and minimize existing cadmium-induced
disease(s).
The levels of cadmium in the urine and blood provide an estimate of
the total amount of cadmium in the body. The amount of a specific
protein in the urine (beta-2-microglobulin) indicates changes in kidney
function. All three tests must be evaluated together. A single mildly
elevated result may not be important if testing at a later time
indicates that the results are normal and the workplace has been
evaluated to decrease possible sources of cadmium exposure. The levels
of cadmium or beta-2-microglobulin may change over a period of days to
months and the time needed for those changes to occur is different for
each worker.
If the results for biological monitoring are above specific ``high
levels'' [cadmium urine greater than 10 micrograms per gram of
creatinine ([micro]g/g Cr), cadmium blood greater than 10 micrograms per
liter of whole blood ([micro]g/lwb), or beta-2-microglobulin greater
than 1000 micrograms per gram of creatinine ([micro]g/g Cr)], the worker
has a much greater chance of developing other kidney diseases.
One way to measure for kidney function is by measuring beta-2-
microglobulin in the urine. Beta-2-microglobulin is a protein which is
normally found in the blood as it is being filtered in the kidney, and
the kidney reabsorbs or returns almost all of the beta-2-microglobulin
to the blood. A very small amount (less than 300 [micro]g/g Cr in the
urine) of beta-2-microglobulin is not reabsorbed into the blood, but is
released in the urine. If cadmium damages the kidney, the amount of
beta-2-microglobulin in the urine increases because the kidney cells are
unable to reabsorb the beta-2-microglobulin normally. An increase in the
amount of beta-2-microglobulin in the urine is a very early sign of
kidney dysfunction. A small increase in beta-2-microglobulin in the
urine will serve as an early warning sign that the worker may be
absorbing cadmium from the air, cigarettes contaminated in the
workplace, or eating in areas that are cadmium contaminated.
Even if cadmium causes permanent changes in the kidney's ability to
reabsorb beta-2-microglobulin, and the beta-2-microglobulin is above the
``high levels'', the loss of kidney function may not lead to any serious
health problems. Also, renal function naturally declines as people age.
The risk for changes in kidney function for workers who have biological
monitoring results between the ``normal values'' and the ``high levels''
is not well known. Some people are more cadmium-tolerant, while others
are more cadmium-susceptible.
For anyone with even a slight increase of beta-2-microglobulin,
cadmium in the urine, or cadmium in the blood, it is very important to
protect the kidney from further damage. Kidney damage can come from
other sources than excess cadmium-exposure so it is also recommended
that if a worker's levels are ``high'' he/she should receive counseling
about drinking more water; avoiding cadmium-tainted tobacco and certain
medications (nephrotoxins, acetaminophen); controlling diet, vitamin
intake, blood pressure and diabetes; etc.
Appendix B toSec. 1910.1027--Substance Technical Guidelines for
Cadmium
I. Cadmium Metal
A. Physical and Chemical Data.
[[Page 168]]
1. Substance Identification.
Chemical name: Cadmium.
Formula: Cd.
Molecular Weight: 112.4.
Chemical Abstracts Service (CAS) Registry No.: 7740-43-9.
Other Identifiers: RETCS EU9800000; EPA D006; DOT 2570 53.
Synonyms: Colloidal Cadmium: Kadmium (German): CI 77180.
2. Physical data.
Boiling point: (760 mm Hg): 765 degrees C.
Melting point: 321 degrees C.
Specific Gravity: (H2 O=@ 20 [deg]C): 8.64.
Solubility: Insoluble in water; soluble in dilute nitric acid and in
sulfuric acid.
Appearance: Soft, blue-white, malleable, lustrous metal or grayish-
white powder.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: The finely divided metal is pyrophoric,
that is the dust is a severe fire hazard and moderate explosion hazard
when exposed to heat or flame. Burning material reacts violently with
extinguishing agents such as water, foam, carbon dioxide, and halons.
Flash point: Flammable (dust).
Extinguishing media: Dry sand, dry dolomite, dry graphite, or
sodimum chloride.
2. Reactivity.
Conditions contributing to instability: Stable when kept in sealed
containers under normal temperatures and pressure, but dust may ignite
upon contact with air. Metal tarnishes in moist air.
Incompatibilities: Ammonium nitrate, fused: Reacts violently or
explosively with cadmium dust below 20 [deg]C. Hydrozoic acid: Violent
explosion occurs after 30 minutes. Acids: Reacts violently, forms
hydrogen gas. Oxidizing agents or metals: Strong reaction with cadmium
dust. Nitryl fluoride at slightly elevated temperature: Glowing or white
incandescence occurs. Selenium: Reacts exothermically. Ammonia:
Corrosive reaction. Sulfur dioxide: Corrosive reaction. Fire
extinguishing agents (water, foam, carbon dioxide, and halons): Reacts
violently. Tellurium: Incandescent reaction in hydrogen atmosphere.
Hazardous decomposition products: The heated metal rapidly forms
highly toxic, brownish fumes of oxides of cadmium.
C. Spill, Leak and Disposal Procedures.
1. Steps to be taken if the materials is released or spilled. Do not
touch spilled material. Stop leak if you can do it without risk. Do not
get water inside container. For large spills, dike spill for later
disposal. Keep unnecessary people away. Isolate hazard area and deny
entry. The Superfund Amendments and Reauthorization Act of 1986 Section
304 requires that a release equal to or greater than the reportable
quantity for this substance (1 pound) must be immediately reported to
the local emergency planning committee, the state emergency response
commission, and the National Response Center (800) 424-8802; in
Washington, DC metropolitan area (202) 426-2675.
II. Cadmium Oxide
A. Physical and Chemical Date.
1. Substance identification.
Chemical name: Cadmium Oxide.
Formula: CdO.
Molecular Weight: 128.4.
CAS No.: 1306-19-0.
Other Identifiers: RTECS EV1929500.
Synonyms: Kadmu tlenek (Polish).
2. Physical data.
Boiling point (760 mm Hg): 950 degrees C decomposes.
Melting point: 1500 [deg]C.
Specific Gravity: (H2 O=1@20 [deg]C): 7.0.
Solubility: Insoluble in water; soluble in acids and alkalines.
Appearance: Red or brown crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Negligible fire hazard when exposed to
heat or flame.
Flash point: Nonflammable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or
foam.
2. Reactivity.
Conditions contributing to instability: Stable under normal
temperatures and pressures.
Incompatibilities: Magnesium may reduce CdO2 explosively
on heating.
Hazardous decomposition products: Toxic fumes of cadmium.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the material is released or spilled. Do not
touch spilled material. Stop leak if you can do it without risk. For
small spills, take up with sand or other absorbent material and place
into containers for later disposal. For small dry spills, use a clean
shovel to place material into clean, dry container and then cover. Move
containers from spill area. For larger spills, dike far ahead of spill
for later disposal. Keep unnecessary people away. Isolate hazard area
and deny entry. The Superfund Amendments and Reauthorization Act of 1986
Section 304 requires that a release equal to or greater than the
reportable quantity for this substance (1 pound) must be immediately
reported to the local emergency planning committee, the state emergency
response commission, and the National Response Center (800) 424-8802; in
Washington, DC metropolitan area (202) 426-2675.
III. Cadmium Sulfide.
A. Physical and Chemical Data.
1. Substance Identification.
Chemical name: Cadmium sulfide.
Formula: CdS.
Molecular weight: 144.5.
CAS No. 1306-23-6.
Other Identifiers: RTECS EV3150000.
Synonyms: Aurora yellow; Cadmium Golden 366; Cadmium Lemon Yellow
527; Cadmium
[[Page 169]]
Orange; Cadmium Primrose 819; Cadmium Sulphide; Cadmium Yellow; Cadmium
Yellow 000; Cadmium Yellow Conc. Deep; Cadmium Yellow Conc. Golden;
Cadmium Yellow Conc. Lemon; Cadmium Yellow Conc. Primrose; Cadmium
Yellow Oz. Dark; Cadmium Yellow Primrose 47-1400; Cadmium Yellow 10G
Conc.; Cadmium Yellow 892; Cadmopur Golden Yellow N; Cadmopur Yellow:
Capsebon; C.I. 77199; C.I. Pigment Orange 20; CI Pigment Yellow 37;
Ferro Lemon Yellow; Ferro Orange Yellow; Ferro Yellow; Greenockite; NCI-
C02711.
2. Physical data.
Boiling point (760 mm. Hg): sublines in N2 at 980 [deg]C.
Melting point: 1750 degrees C (100 atm).
Specific Gravity: (H2 O=1@ 20 [deg]C): 4.82.
Solubility: Slightly soluble in water; soluble in acid.
Appearance: Light yellow or yellow-orange crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Neglible fire hazard when exposed to
heat or flame.
Flash point: Nonflammable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or
foam.
2. Reactivity.
Conditions contributing to instability: Generally non-reactive under
normal conditions. Reacts with acids to form toxic hydrogen sulfide gas.
Incompatibilities: Reacts vigorously with iodinemonochloride.
Hazardous decomposition products: Toxic fumes of cadmium and sulfur
oxides.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the material is released or spilled. Do not
touch spilled material. Stop leak if you can do it without risk. For
small, dry spills, with a clean shovel place material into clean, dry
container and cover. Move containers from spill area. For larger spills,
dike far ahead of spill for later disposal. Keep unnecessary people
away. Isolate hazard and deny entry.
IV. Cadmium Chloride.
A. Physical and Chemical Data.
1. Substance Identification.
Chemcail name: Cadmium chloride.
Formula: CdC12.
Molecular weight: 183.3.
CAS No. 10108-64-2.
Other Identifiers: RTECS EY0175000.
Synonyms: Caddy; Cadmium dichloride; NA 2570 (DOT); UI-CAD;
dichlorocadmium.
2. Physical data.
Boiling point (760 mm Hg): 960 degrees C.
Melting point: 568 degrees C.
Specific Gravity: (H2 O=1 @ 20 [deg]C): 4.05.
Solubility: Soluble in water (140 g/100 cc); soluble in acetone.
Appearance: Small, white crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Negligible fire and negligible explosion
hazard in dust form when exposed to heat or flame.
Flash point: Nonflamable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or
foam.
2. Reactivity.
Conditions contributing to instability: Generally stable under
normal temperatures and pressures.
Incompatibilities: Bromine trifluoride rapidly attacks cadmium
chloride. A mixture of potassium and cadmium chloride may produce a
strong explosion on impact.
Hazardous decomposition products: Thermal ecompostion may release
toxic fumes of hydrogen chloride, chloride, chlorine or oxides of
cadmium.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the materials is released or spilled. Do not
touch spilled material. Stop leak if you can do it without risk. For
small, dry spills, with a clean shovel place material into clean, dry
container and cover. Move containers from spill area. For larger spills,
dike far ahead of spill for later disposal. Keep unnecessary people
away. Isolate hazard and deny entry. The Superfund Amendments and
Reauthorization Act of 1986 Section 304 requires that a release equal to
or greater than the reportable quantity for this substance (100 pounds)
must be immediately reported to the local emergency planning committee,
the state emergency response commission, and the National Response
Center (800) 424-8802; in Washington, DC Metropolitan area (202) 426-
2675.
Appendix C toSec. 1910.1027 [Reserved]
Appendix D toSec. 1910.1027--Occupational Health History Interview
With Reference to Cadmium Exposure
Directions
(To be read by employee and signed prior to the interview)
Please answer the questions you will be asked as completely and
carefully as you can. These questions are asked of everyone who works
with cadmium. You will also be asked to give blood and urine samples.
The doctor will give your employer a written opinion on whether you are
physically capable of working with cadmium. Legally, the doctor cannot
share personal information you may tell him/her with your employer. The
following information is considered strictly confidential. The results
of the tests will go to you, your doctor and your employer. You will
also receive an information sheet explaining the results of any
biological monitoring or physical examinations performed.
If you are just being hired, the results of this interview and
examination will be used to:
[[Page 170]]
(1) Establish your health status and see if working with cadmium
might be expected to cause unusual problems,
(2) Determine your health status today and see if there are changes
over time,
(3) See if you can wear a respirator safely.
If you are not a new hire:
OSHA says that everyone who works with cadmium can have periodic
medical examinations performed by a doctor. The reasons for this are:
(a) If there are changes in your health, either because of cadmium
or some other reason, to find them early,
(b) to prevent kidney damage.
Please sign below.
I have read these directions and understand them:
________________________________________________________________________
Employee signature
________________________________________________________________________
Date
Thank you for answering these questions. (Suggested Format)
Name____________________________________________________________________
Age_____________________________________________________________________
Social Security _______________________________________________
Company_________________________________________________________________
Job_____________________________________________________________________
Type of Preplacement Exam:
[ ] Periodic
[ ] Termination
[ ] Initial
[ ] Other
Blood Pressure__________________________________________________________
Pulse Rate______________________________________________________________
1. How long have you worked at the job listed above?
[ ] Not yet hired
[ ] Number of months
[ ] Number of years
2. Job Duties etc.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
3. Have you ever been told by a doctor that you had bronchitis?
[ ] Yes
[ ] No
If yes, how long ago?
[ ] Number of months
[ ] Number of years
4. Have you ever been told by a doctor that you had emphysema?
[ ] Yes
[ ] No
If yes, how long ago?
[ ] Number of years
[ ] Number of months
5. Have you ever been told by a doctor that you had other lung problems?
[ ] Yes
[ ] No
If yes, please describe type of lung problems and when you had these
problems
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
6. In the past year, have you had a cough?
[ ] Yes
[ ] No
If yes, did you cough up sputum?
[ ] Yes
[ ] No
If yes, how long did the cough with sputum production last?
[ ] Less than 3 months
[ ] 3 months or longer
If yes, for how many years have you had episodes of cough with
sputum production lasting this long?
[ ] Less than one
[ ] 1
[ ] 2
[ ] Longer than 2
7. Have you ever smoked cigarettes?
[ ] Yes
[ ] No
8. Do you now smoke cigarettes?
[ ] Yes
[ ] No
9. If you smoke or have smoked cigarettes, for how many years have you
smoked, or did you smoke?
[ ] Less than 1 year
[ ] Number of years
What is or was the greatest number of packs per day that you have
smoked?
[ ] Number of packs
If you quit smoking cigarettes, how many years ago did you quit?
[ ] Less than 1 year
[ ] Number of years
How many packs a day do you now smoke?
[ ] Number of packs per day
10. Have you ever been told by a doctor that you had a kidney or urinary
tract disease or disorder?
[ ] Yes
[ ] No
11. Have you ever had any of these disorders?
Kidney stones...................... [ ] Yes [ ] No
Protein in urine................... [ ] Yes [ ] No
Blood in urine..................... [ ] Yes [ ] No
Difficulty urinating............... [ ] Yes [ ] No
Other kidney/Urinary disorders..... [ ] Yes [ ] No
Please describe problems, age, treatment, and follow up for any
kidney or urinary problems you have had:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
12. Have you ever been told by a doctor or other health care provider
who took your blood pressure that your blood pressure was
high?
[ ] Yes
[ ] No
13. Have you ever been advised to take any blood pressure medication?
[[Page 171]]
[ ] Yes
[ ] No
14. Are you presently taking any blood pressure medication?
[ ] Yes
[ ] No
15. Are you presently taking any other medication?
[ ] Yes
[ ] No
16. Please list any blood pressure or other medications and describe how
long you have been taking each one:
Medicine:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
How Long Taken
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
17. Have you ever been told by a doctor that you have diabetes? (sugar
in your blood or urine)
[ ] Yes
[ ] No
If yes, do you presently see a doctor about your diabetes?
[ ] Yes
[ ] No
If yes, how do you control your blood sugar?
[ ] Diet alone
[ ] Diet plus oral medicine
[ ] Diet plus insulin (injection)
18. Have you ever been told by a doctor that you had:
Anemia............................. [ ] Yes [ ] No
A low blood count?................. [ ] Yes [ ] No
19. Do you presently feel that you tire or run out of energy sooner than
normal or sooner than other people your age?
[ ] Yes
[ ] No
If yes, for how long have you felt that you tire easily?
[ ] Less than 1 year
[ ] Number of years
20. Have you given blood within the last year?
[ ] Yes
[ ] No
If yes, how many times?
[ ] Number of times
How long ago was the last time you gave blood?
[ ] Less than 1 month
[ ] Number of months
21. Within the last year have you had any injuries with heavy bleeding?
[ ] Yes
[ ] No
If yes, how long ago?
[ ] Less than 1 month
[ ] Number of months
Describe:_______________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
22. Have you recently had any surgery?
[ ] Yes
[ ] No
If yes, please describe:________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
23. Have you seen any blood lately in your stool or after a bowel
movement?
[ ] Yes
[ ] No
24. Have you ever had a test for blood in your stool?
[ ] Yes
[ ] No
If yes, did the test show any blood in the stool?
[ ] Yes
[ ] No
What further evaluation and treatment were done?________________________
________________________________________________________________________
________________________________________________________________________
The following questions pertain to the ability to wear a respirator.
Additional information for the physician can be found in The Respiratory
Protective Devices Manual.
25. Have you ever been told by a doctor that you have asthma?
[ ] Yes
[ ] No
If yes, are you presently taking any medication for asthma? Mark all
that apply.
[ ] Shots
[ ] Pills
[ ] Inhaler
26. Have you ever had a heart attack?
[ ] Yes
[ ] No
If yes, how long ago?
[ ] Number of years
[ ] Number of months
27. Have you ever had pains in your chest?
[ ] Yes
[ ] No
If yes, when did it usually happen?
[ ] While resting
[ ] While working
[ ] While exercising
[ ] Activity didn't matter
28. Have you ever had a thyroid problem?
[ ] Yes
[ ] No
29. Have you ever had a seizure or fits?
[ ] Yes
[ ] No
30. Have you ever had a stroke (cerebrovascular accident)?
[ ] Yes
[ ] No
31. Have you ever had a ruptured eardrum or a serious hearing problem?
[ ] Yes
[ ] No
[[Page 172]]
32. Do you now have a claustrophobia, meaning fear of crowded or closed
in spaces or any psychological problems that would make it
hard for you to wear a respirator?
[ ] Yes
[ ] No
The following questions pertain to reproductive history.
33. Have you or your partner had a problem conceiving a child?
[ ] Yes
[ ] No
If yes, specify:
[ ] Self
[ ] Present mate
[ ] Previous mate
34. Have you or your partner consulted a physician for a fertility or
other reproductive problem?
[ ] Yes
[ ] No
If yes, specify who consulted the physician:
[ ] Self
[ ] Spouse/partner
[ ] Self and partner
If yes, specify diagnosis made:_________________________________________
________________________________________________________________________
________________________________________________________________________
35. Have you or your partner ever conceived a child resulting in a
miscarriage, still birth or deformed offspring?
[ ] Yes
[ ] No
If yes, specify:
[ ] Miscarriage
[ ] Still birth
[ ] Deformed offspring
If outcome was a deformed offspring, please specify type:_______________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
36. Was this outcome a result of a pregnancy of:
[ ] Yours with present partner
[ ] Yours with a previous partner
37. Did the timing of any abnormal pregnancy outcome coincide with
present employment?
[ ] Yes
[ ] No
List dates of occurrences:______________________________________________
________________________________________________________________________
38. What is the occupation of your spouse or partner?
________________________________________________________________________
________________________________________________________________________
For Women Only
39. Do you have menstrual periods?
[ ] Yes
[ ] No
Have you had menstrual irregularities?
[ ] Yes
[ ] No
If yes, specify type:___________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
If yes, what was the approximated date this problem began?______________
________________________________________________________________________
Approximate date problem stopped?_______________________________________
________________________________________________________________________
For Men Only
40. Have you ever been diagnosed by a physician as having prostate gland
problem(s)?
[ ] Yes
[ ] No
If yes, please describe type of problem(s) and what was done to evaluate
and treat the problem(s):_______________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
Appendix E toSec. 1910.1027--Cadmium in Workplace Atmospheres
Method Number: ID-189
Matrix: Air
OSHA Permissible Exposure Limits: 5 [micro]g/m\3\ (TWA), 2.5 [micro]g/
m\3\ (Action Level TWA)
Collection Procedure: A known volume of air is drawn through a 37-mm
diameter filter cassette containing a 0.8-[micro]m mixed
cellulose ester membrane filter (MCEF).
Recommended Air Volume: 960 L
Recommended Sampling Rate: 2.0 L/min
Analytical Procedure: Air filter samples are digested with nitric acid.
After digestion, a small amount of hydrochloric acid is added.
The samples are then diluted to volume with deionized water
and analyzed by either flame atomic absorption spectroscopy
(AAS) or flameless atomic absorption spectroscopy using a
heated graphite furnace atomizer (AAS-HGA).
Detection Limits:
Qualitative: 0.2 [micro]g/m\3\ for a 200 L sample by Flame AAS, 0.007
[micro]g/m\3\ for a 60 L sample by AAS-HGA
Quantitative: 0.70 [micro]g/m\3\ for a 200 L sample by Flame AAS, 0.025
[micro]g/m\3\ for a 60 L sample by AAS-HGA
Precision and Accuracy: (Flame AAS Analysis and AAS-HGA Analysis):
Validation Level: 2.5 to 10 [micro]g/m\3\ for a 400 L air vol, 1.25
to 5.0 [micro]g/m\3\ for a 60 L air vol
CV1 (pooled): 0.010, 0.043
Analytical Bias: +4.0%, -5.8%
Overall Analytical Error:6.0%, 14.2%
Method Classification: Validated
Date: June, 1992
Inorganic Service Branch II, OSHA Salt Lake Technical Center, Salt
Lake City, Utah
Commercial manufacturers and products mentioned in this method are
for descriptive use only and do not constitute endorsements by USDOL-
OSHA. Similar products from other sources can be substituted.
[[Page 173]]
1. Introduction
1.1. Scope
This method describes the collection of airborne elemental cadmium
and cadmium compounds on 0.8-[micro]m mixed cellulose ester membrane
filters and their subsequent analysis by either flame atomic absorption
spectroscopy (AAS) or flameless atomic absorption spectroscopy using a
heated graphite furnace atomizer (AAS-HGA). It is applicable for both
TWA and Action Level TWA Permissible Exposure Level (PEL) measurements.
The two atomic absorption analytical techniques included in the method
do not differentiate between cadmium fume and cadmium dust samples. They
also do not differentiate between elemental cadmium and its compounds.
1.2. Principle
Airborne elemental cadmium and cadmium compounds are collected on a
0.8-[micro]m mixed cellulose ester membrane filter (MCEF). The air
filter samples are digested with concentrated nitric acid to destroy the
organic matrix and dissolve the cadmium analytes. After digestion, a
small amount of concentrated hydrochloric acid is added to help dissolve
other metals which may be present. The samples are diluted to volume
with deionized water and then aspirated into the oxidizing air/acetylene
flame of an atomic absorption spectrophotometer for analysis of
elemental cadmium.
If the concentration of cadmium in a sample solution is too low for
quantitation by this flame AAS analytical technique, and the sample is
to be averaged with other samples for TWA calculations, aliquots of the
sample and a matrix modifier are later injected onto a L'vov platform in
a pyrolytically-coated graphite tube of a Zeeman atomic absorption
spectrophotometer/graphite furnace assembly for analysis of elemental
cadmium. The matrix modifier is added to stabilize the cadmium metal and
minimize sodium chloride as an interference during the high temperature
charring step of the analysis (5.1., 5.2.).
1.3. History
Previously, two OSHA sampling and analytical methods for cadmium
were used concurrently (5.3., 5.4.). Both of these methods also required
0.8-[micro]m mixed cellulose ester membrane filters for the collection
of air samples. These cadmium air filter samples were analyzed by either
flame atomic absorption spectroscopy (5.3.) or inductively coupled
plasma/atomic emission spectroscopy (ICP-AES) (5.4.). Neither of these
two analytical methods have adequate sensitivity for measuring workplace
exposure to airborne cadmium at the new lower TWA and Action Level TWA
PEL levels when consecutive samples are taken on one employee and the
sample results need to be averaged with other samples to determine a
single TWA.
The inclusion of two atomic absorption analytical techniques in the
new sampling and analysis method for airborne cadmium permits
quantitation of sample results over a broad range of exposure levels and
sampling periods. The flame AAS analytical technique included in this
method is similar to the previous procedure given in the General Metals
Method ID-121 (5.3.) with some modifications. The sensitivity of the
AAS-HGA analytical technique included in this method is adequate to
measure exposure levels at \1/10\ the Action Level TWA, or lower, when
less than full-shift samples need to be averaged together.
1.4. Properties (5.5.)
Elemental cadmium is a silver-white, blue-tinged, lustrous metal
which is easily cut with a knife. It is slowly oxidized by moist air to
form cadmium oxide. It is insoluble in water, but reacts readily with
dilute nitric acid. Some of the physical properties and other
descriptive information of elemental cadmium are given below:
CAS No.........................................................7440-43-9
Atomic Number.........................................................48
Atomic Symbol.........................................................Cd
Atomic Weight.....................................................112.41
Melting Point.................................................321 [deg]C
Boiling Point.................................................765 [deg]C
Density............................................8.65 g/mL (25 [deg]C)
The properties of specific cadmium compounds are described in
reference 5.5.
1.5. Method Performance
A synopsis of method performance is presented below. Further
information can be found in Section 4.
1.5.1. The qualitative and quantitative detection limits for the
flame AAS analytical technique are 0.04 [micro]g (0.004 [micro]g/mL) and
0.14 [micro]g (0.014 [micro]g/mL) cadmium, respectively, for a 10 mL
solution volume. These correspond, respectively, to 0.2 [micro]g/m\3\
and 0.70 [micro]g/m\3\ for a 200 L air volume.
1.5.2. The qualitative and quantitative detection limits for the
AAS-HGA analytical technique are 0.44 ng (0.044 ng/mL) and 1.5 ng (0.15
ng/mL) cadmium, respectively, for a 10 mL solution volume. These
correspond, respectively, to 0.007 [micro]g/m\3\ and 0.025 [micro]g/m\3\
for a 60 L air volume.
1.5.3. The average recovery by the flame AAS analytical technique of
17 spiked MCEF samples containing cadmium in the range of 0.5 to 2.0
times the TWA target concentration of 5 [micro]g/m\3\ (assuming a 400 L
air volume) was 104.0% with a pooled coefficient of variation
(CV1) of 0.010. The flame analytical technique exhibited a
positive bias of +4.0% for the validated concentration range. The
overall analytical error (OAE) for the flame AAS analytical technique
was 6.0%.
[[Page 174]]
1.5.4. The average recovery by the AAS-HGA analytical technique of
18 spiked MCEF samples containing cadmium in the range of 0.5 to 2.0
times the Action Level TWA target concentration of 2.5 [micro]g/m\3\
(assuming a 60 L air volume) was 94.2% with a pooled coefficient of
variation (CV1) of 0.043. The AAS-HGA analytical technique
exhibited a negative bias of -5.8% for the validated concentration
range. The overall analytical error (OAE) for the AAS-HGA analytical
technique was 14.2%.
1.5.5. Sensitivity in flame atomic absorption is defined as the
characteristic concentration of an element required to produce a signal
of 1% absorbance (0.0044 absorbance units). Sensitivity values are
listed for each element by the atomic absorption spectrophotometer
manufacturer and have proved to be a very valuable diagnostic tool to
determine if instrumental parameters are optimized and if the instrument
is performing up to specification. The sensitivity of the
spectrophotometer used in the validation of the flame AAS analytical
technique agreed with the manufacturer specifications (5.6.); the 2
[micro]g/mL cadmium standard gave an absorbance reading of 0.350 abs.
units.
1.5.6. Sensitivity in graphite furnace atomic absorption is defined
in terms of the characteristic mass, the number of picograms required to
give an integrated absorbance value of 0.0044 absorbance-second (5.7.).
Data suggests that under Stabilized Temperature Platform Furnace (STPF)
conditions (see Section 1.6.2.), characteristic mass values are
transferable between properly functioning instruments to an accuracy of
about 20% (5.2.). The characteristic mass for STPF analysis of cadmium
with Zeeman background correction listed by the manufacturer of the
instrument used in the validation of the AAS-HGA analytical technique
was 0.35 pg. The experimental characteristic mass value observed during
the determination of the working range and detection limits of the AAS-
HGA analytical technique was 0.41 pg.
1.6. Interferences
1.6.1. High concentrations of silicate interfere in determining
cadmium by flame AAS (5.6.). However, silicates are not significantly
soluble in the acid matrix used to prepare the samples.
1.6.2. Interferences, such as background absorption, are reduced to
a minimum in the AAS-HGA analytical technique by taking full advantage
of the Stabilized Temperature Platform Furnace (STPF) concept. STPF
includes all of the following parameters (5.2.):
a. Integrated Absorbance,
b. Fast Instrument Electronics and Sampling Frequency,
c. Background Correction,
d. Maximum Power Heating,
e. Atomization off the L'vov platform in a pyrolytically coated graphite
tube,
f. Gas Stop during Atomization,
g. Use of Matrix Modifiers.
1.7. Toxicology (5.14.)
Information listed within this section is synopsis of current
knowledge of the physiological effects of cadmium and is not intended to
be used as the basis for OSHA policy. IARC classifies cadmium and
certain of its compounds as Group 2A carcinogens (probably carcinogenic
to humans). Cadmium fume is intensely irritating to the respiratory
tract. Workplace exposure to cadmium can cause both chronic and acute
effects. Acute effects include tracheobronchitis, pneumonitis, and
pulmonary edema. Chronic effects include anemia, rhinitis/anosmia,
pulmonary emphysema, proteinuria and lung cancer. The primary target
organs for chronic disease are the kidneys (non-carcinogenic) and the
lungs (carcinogenic).
2. Sampling
2.1. Apparatus
2.1.1. Filter cassette unit for air sampling: A 37-mm diameter mixed
cellulose ester membrane filter with a pore size of 0.8-[micro]m
contained in a 37-mm polystyrene two- or three-piece cassette filter
holder (part no. MAWP 037 A0, Millipore Corp., Bedford, MA). The filter
is supported with a cellulose backup pad. The cassette is sealed prior
to use with a shrinkable gel band.
2.1.2. A calibrated personal sampling pump whose flow is determined
to an accuracy of 5% at the recommended flow rate
with the filter cassette unit in line.
2.2. Procedure
2.2.1. Attach the prepared cassette to the calibrated sampling pump
(the backup pad should face the pump) using flexible tubing. Place the
sampling device on the employee such that air is sampled from the
breathing zone.
2.2.2. Collect air samples at a flow rate of 2.0 L/min. If the
filter does not become overloaded, a full-shift (at least seven hours)
sample is strongly recommended for TWA and Action Level TWA measurements
with a maximum air volume of 960 L. If overloading occurs, collect
consecutive air samples for shorter sampling periods to cover the full
workshift.
2.2.3. Replace the end plugs into the filter cassettes immediately
after sampling. Record the sampling conditions.
2.2.4. Securely wrap each sample filter cassette end-to-end with an
OSHA Form 21 sample seal.
[[Page 175]]
2.2.5. Submit at least one blank sample with each set of air
samples. The blank sample should be handled the same as the other
samples except that no air is drawn through it.
2.2.6. Ship the samples to the laboratory for analysis as soon as
possible in a suitable container designed to prevent damage in transit.
3. Analysis
3.1. Safety Precautions
3.1.1. Wear safety glasses, protective clothing and gloves at all
times.
3.1.2. Handle acid solutions with care. Handle all cadmium samples
and solutions with extra care (see Sect. 1.7.). Avoid their direct
contact with work area surfaces, eyes, skin and clothes. Flush acid
solutions which contact the skin or eyes with copious amounts of water.
3.1.3. Perform all acid digestions and acid dilutions in an exhaust
hood while wearing a face shield. To avoid exposure to acid vapors, do
not remove beakers containing concentrated acid solutions from the
exhaust hood until they have returned to room temperature and have been
diluted or emptied.
3.1.4. Exercise care when using laboratory glassware. Do not use
chipped pipets, volumetric flasks, beakers or any glassware with sharp
edges exposed in order to avoid the possibility of cuts or abrasions.
3.1.5. Never pipet by mouth.
3.1.6. Refer to the instrument instruction manuals and SOPs (5.8.,
5.9.) for proper and safe operation of the atomic absorption
spectrophotometer, graphite furnace atomizer and associated equipment.
3.1.7. Because metallic elements and other toxic substances are
vaporized during AAS flame or graphite furnace atomizer operation, it is
imperative that an exhaust vent be used. Always ensure that the exhaust
system is operating properly during instrument use.
3.2. Apparatus for Sample and Standard Preparation
3.2.1. Hot plate, capable of reaching 150 [deg]C, installed in an
exhaust hood.
3.2.2. Phillips beakers, 125 mL.
3.2.3. Bottles, narrow-mouth, polyethylene or glass with leakproof
caps: used for storage of standards and matrix modifier.
3.2.4. Volumetric flasks, volumetric pipets, beakers and other
associated general laboratory glassware.
3.2.5. Forceps and other associated general laboratory equipment.
3.3. Apparatus for Flame AAS Analysis
3.3.1. Atomic absorption spectrophotometer consisting of a(an):
Nebulizer and burner head
Pressure regulating devices capable of maintaining constant oxidant and
fuel pressures
Optical system capable of isolating the desired wavelength of radiation
(228.8 nm)
Adjustable slit
Light measuring and amplifying device
Display, strip chart, or computer interface for indicating the amount of
absorbed radiation
Cadmium hollow cathode lamp or electrodeless discharge lamp (EDL) and
power supply
3.3.2. Oxidant: compressed air, filtered to remove water, oil and
other foreign substances.
3.3.3. Fuel: standard commercially available tanks of acetylene
dissolved in acetone; tanks should be equipped with flash arresters.
Caution: Do not use grades of acetylene containing solvents other
than acetone because they may damage the PVC tubing used in some
instruments.
3.3.4. Pressure-reducing valves: two gauge, two-stage pressure
regulators to maintain fuel and oxidant pressures somewhat higher than
the controlled operating pressures of the instrument.
3.3.5. Exhaust vent installed directly above the spectrophotometer
burner head.
3.4. Apparatus for AAS-HGA Analysis
3.4.1. Atomic absorption spectrophotometer consisting of a(an):
Heated graphite furnace atomizer (HGA) with argon purge system
Pressure-regulating devices capable of maintaining constant argon purge
pressure
Optical system capable of isolating the desired wavelength of radiation
(228.8 nm)
Adjustable slit
Light measuring and amplifying device
Display, strip chart, or computer interface for indicating the amount of
absorbed radiation (as integrated absorbance, peak area)
Background corrector: Zeeman or deuterium arc. The Zeeman background
corrector is recommended
Cadmium hollow cathode lamp or electrodeless discharge lamp (EDL) and
power supply
Autosampler capable of accurately injecting 5 to 20 [micro]L sample
aliquots onto the L'vov Platform in a graphite tube
3.4.2. Pyrolytically coated graphite tubes containing solid,
pyrolytic L'vov platforms.
3.4.3. Polyethylene sample cups, 2.0 to 2.5 mL, for use with the
autosampler.
3.4.4. Inert purge gas for graphite furnace atomizer: compressed gas
cylinder of purified argon.
3.4.5. Two gauge, two-stage pressure regulator for the argon gas
cylinder.
3.4.6. Cooling water supply for graphite furnace atomizer.
[[Page 176]]
3.4.7. Exhaust vent installed directly above the graphite furnace
atomizer.
3.5. Reagents
All reagents should be ACS analytical reagent grade or better.
3.5.1. Deionized water with a specific conductance of less than 10
[micro]S.
3.5.2. Concentrated nitric acid, HNO3.
3.5.3. Concentrated hydrochloric acid, HCl.
3.5.4. Ammonium phosphate, monobasic, NH4 H2
PO4.
3.5.5. Magnesium nitrate, Mg(NO3)2 [middot]
6H2 O.
3.5.6. Diluting solution (4% HNO3, 0.4% HCl): Add 40 mL
HNO3 and 4 mL HCl carefully to approximately 500 mL deionized
water and dilute to 1 L with deionized water.
3.5.7. Cadmium standard stock solution, 1,000 [micro]g/mL: Use a
commercially available certified 1,000 [micro]g/mL cadmium standard or,
alternatively, dissolve 1.0000 g of cadmium metal in a minimum volume of
1:1 HCl and dilute to 1 L with 4% HNO3. Observe expiration
dates of commercial standards. Properly dispose of commercial standards
with no expiration dates or prepared standards one year after their
receipt or preparation date.
3.5.8. Matrix modifier for AAS-HGA analysis: Dissolve 1.0 g
NH4 H2 PO4 and 0.15 g
Mg(NO3)2 [middot] 6H2 O in
approximately 200 mL deionized water. Add 1 mL HNO3 and
dilute to 500 mL with deionized water.
3.5.9 Nitric Acid, 1:1 HNO3/DI H2 O mixture:
Carefully add a measured volume of concentrated HNO3 to an
equal volume of DI H2 O.
3.5.10. Nitric acid, 10% v/v: Carefully add 100 mL of concentrated
HNO3 to 500 mL of DI H2 O and dilute to 1 L.
3.6. Glassware Preparation
3.6.1. Clean Phillips beakers by refluxing with 1:1 nitric acid on a
hot plate in a fume hood. Thoroughly rinse with deionized water and
invert the beakers to allow them to drain dry.
3.6.2. Rinse volumetric flasks and all other glassware with 10%
nitric acid and deionized water prior to use.
3.7. Standard Preparation for Flame AAS Analysis
3.7.1. Dilute stock solutions: Prepare 1, 5, 10 and 100 [micro]g/mL
cadmium standard stock solutions by making appropriate serial dilutions
of 1,000 [micro]g/mL cadmium standard stock solution with the diluting
solution described in Section 3.5.6.
3.7.2. Working standards: Prepare cadmium working standards in the
range of 0.02 to 2.0 [micro]g/mL by making appropriate serial dilutions
of the dilute stock solutions with the same diluting solution. A
suggested method of preparation of the working standards is given below.
------------------------------------------------------------------------
Std Final
Working standard solution Aliquot vol.
------------------------------------------------------------------------
([micro]g/mL) ([micro]g/ (mL) (mL)
mL)
------------------------------------------------------------------------
0.02................................... 1 10 500
0.05................................... 5 5 500
0.1.................................... 10 5 500
0.2.................................... 10 10 500
0.5.................................... 10 25 500
1...................................... 100 5 500
2...................................... 100 10 500
Store the working standards in 500-mL, narrow-mouth polyethylene or
glass bottles with leak proof caps. Prepare every twelve months.
3.8. Standard Preparation for AAS-HGA Analysis
3.8.1. Dilute stock solutions: Prepare 10, 100 and 1,000 ng/mL
cadmium standard stock solutions by making appropriate ten-fold serial
dilutions of the 1,000 [micro]g/mL cadmium standard stock solution with
the diluting solution described in Section 3.5.6.
3.8.2. Working standards: Prepare cadmium working standards in the
range of 0.2 to 20 ng/mL by making appropriate serial dilutions of the
dilute stock solutions with the same diluting solution. A suggested
method of preparation of the working standards is given below.
------------------------------------------------------------------------
Std Final
Working standard solution Aliquot vol.
------------------------------------------------------------------------
(ng/mL) (ng/mL) (mL) (mL)
------------------------------------------------------------------------
0.2.................................... 10 2 100
0.5.................................... 10 5 100
1...................................... 10 10 100
2...................................... 100 2 100
5...................................... 100 5 100
10..................................... 100 10 100
20..................................... 1,000 2 100
Store the working standards in narrow-mouth polyethylene or glass
bottles with leakproof caps. Prepare monthly.
3.9. Sample Preparation
3.9.1. Carefully transfer each sample filter with forceps from its
filter cassette unit to a clean, separate 125-mL Phillips beaker along
with any loose dust found in the cassette. Label each Phillips beaker
with the appropriate sample number.
3.9.2. Digest the sample by adding 5 mL of concentrated nitric acid
(HNO3) to each Phillips beaker containing an air filter
sample. Place the Phillips beakers on a hot plate in an exhaust hood and
heat the samples until approximately 0.5 mL remains. The sample solution
in each Phillips beaker should become clear. If it is not clear, digest
the sample with another portion of concentrated nitric acid.
3.9.3. After completing the HNO3 digestion and cooling
the samples, add 40 [micro]L (2 drops)
[[Page 177]]
of concentrated HCl to each air sample solution and then swirl the
contents. Carefully add about 5 mL of deionized water by pouring it down
the inside of each beaker.
3.9.4. Quantitatively transfer each cooled air sample solution from
each Phillips beaker to a clean 10-mL volumetric flask. Dilute each
flask to volume with deionized water and mix well.
3.10. Flame AAS Analysis
Analyze all of the air samples for their cadmium content by flame
atomic absorption spectroscopy (AAS) according to the instructions given
below.
3.10.1. Set up the atomic absorption spectrophotometer for the air/
acetylene flame analysis of cadmium according to the SOP (5.8.) or the
manufacturer's operational instructions. For the source lamp, use the
cadmium hollow cathode or electrodeless discharge lamp operated at the
manufacturer's recommended rating for continuous operation. Allow the
lamp to warm up 10 to 20 min or until the energy output stabilizes.
Optimize conditions such as lamp position, burner head alignment, fuel
and oxidant flow rates, etc. See the SOP or specific instrument manuals
for details. Instrumental parameters for the Perkin-Elmer Model 603 used
in the validation of this method are given in Attachment 1.
3.10.2. Aspirate and measure the absorbance of a standard solution
of cadmium. The standard concentration should be within the linear
range. For the instrumentation used in the validation of this method a 2
[micro]g/mL cadmium standard gives a net absorbance reading of about
0.350 abs. units (see Section 1.5.5.) when the instrument and the source
lamp are performing to manufacturer specifications.
3.10.3. To increase instrument response, scale expand the absorbance
reading of the aspirated 2 [micro]g/mL working standard approximately
four times. Increase the integration time to at least 3 seconds to
reduce signal noise.
3.10.4. Autozero the instrument while aspirating a deionized water
blank. Monitor the variation in the baseline absorbance reading
(baseline noise) for a few minutes to insure that the instrument, source
lamp and associated equipment are in good operating condition.
3.10.5. Aspirate the working standards and samples directly into the
flame and record their absorbance readings. Aspirate the deionized water
blank immediately after every standard or sample to correct for and
monitor any baseline drift and noise. Record the baseline absorbance
reading of each deionized water blank. Label each standard and sample
reading and its accompanying baseline reading.
3.10.6. It is recommended that the entire series of working
standards be analyzed at the beginning and end of the analysis of a set
of samples to establish a concentration-response curve, ensure that the
standard readings agree with each other and are reproducible. Also,
analyze a working standard after every five or six samples to monitor
the performance of the spectrophotometer. Standard readings should agree
within 10 to 15% of the readings obtained at the
beginning of the analysis.
3.10.7. Bracket the sample readings with standards during the
analysis. If the absorbance reading of a sample is above the absorbance
reading of the highest working standard, dilute the sample with diluting
solution and reanalyze. Use the appropriate dilution factor in the
calculations.
3.10.8. Repeat the analysis of approximately 10% of the samples for
a check of precision.
3.10.9. If possible, analyze quality control samples from an
independent source as a check on analytical recovery and precision.
3.10.10. Record the final instrument settings at the end of the
analysis. Date and label the output.
3.11. AAS-HGA Analysis
Initially analyze all of the air samples for their cadmium content
by flame atomic absorption spectroscopy (AAS) according to the
instructions given in Section 3.10. If the concentration of cadmium in a
sample solution is less than three times the quantitative detection
limit [0.04 [micro]g/mL (40 ng/mL) for the instrumentation used in the
validation] and the sample results are to be averaged with other samples
for TWA calculations, proceed with the AAS-HGA analysis of the sample as
described below.
3.11.1. Set up the atomic absorption spectrophotometer and HGA for
flameless atomic absorption analysis of cadmium according to the SOP
(5.9.) or the manufacturer's operational instructions and allow the
instrument to stabilize. The graphite furnace atomizer is equipped with
a pyrolytically coated graphite tube containing a pyrolytic platform.
For the source lamp, use a cadmium hollow cathode or electrodeless
discharge lamp operated at the manufacturer's recommended setting for
graphite furnace operation. The Zeeman background corrector and EDL are
recommended for use with the L'vov platform. Instrumental parameters for
the Perkin-Elmer Model 5100 spectrophotometer and Zeeman HGA-600
graphite furnace used in the validation of this method are given in
Attachment 2.
3.11.2. Optimize the energy reading of the spectrophotometer at
228.8 nm by adjusting the lamp position and the wavelength according to
the manufacturer's instructions.
3.11.3. Set up the autosampler to inject a 5-[micro]L aliquot of the
working standard, sample or reagent blank solution onto the L'vov
[[Page 178]]
platform along with a 10-[micro]L overlay of the matrix modifier.
3.11.4. Analyze the reagent blank (diluting solution, Section
3.5.6.) and then autozero the instrument before starting the analysis of
a set of samples. It is recommended that the reagent blank be analyzed
several times during the analysis to assure the integrated absorbance
(peak area) reading remains at or near zero.
3.11.5. Analyze a working standard approximately midway in the
linear portion of the working standard range two or three times to check
for reproducibility and sensitivity (see sections 1.5.5. and 1.5.6.)
before starting the analysis of samples. Calculate the experimental
characteristic mass value from the average integrated absorbance reading
and injection volume of the analyzed working standard. Compare this
value to the manufacturer's suggested value as a check of proper
instrument operation.
3.11.6. Analyze the reagent blank, working standard, and sample
solutions. Record and label the peak area (abs-sec) readings and the
peak and background peak profiles on the printer/plotter.
3.11.7. It is recommended the entire series of working standards be
analyzed at the beginning and end of the analysis of a set of samples.
Establish a concentration-response curve and ensure standard readings
agree with each other and are reproducible. Also, analyze a working
standard after every five or six samples to monitor the performance of
the system. Standard readings should agree within 15% of the readings obtained at the beginning of the
analysis.
3.11.8. Bracket the sample readings with standards during the
analysis. If the peak area reading of a sample is above the peak area
reading of the highest working standard, dilute the sample with the
diluting solution and reanalyze. Use the appropriate dilution factor in
the calculations.
3.11.9. Repeat the analysis of approximately 10% of the samples for
a check of precision.
3.11.10. If possible, analyze quality control samples from an
independent source as a check of analytical recovery and precision.
3.11.11. Record the final instrument settings at the end of the
analysis. Date and label the output.
3.12. Calculations
Note: Standards used for HGA analysis are in ng/mL. Total amounts of
cadmium from calculations will be in ng (not [micro]g) unless a prior
conversion is made.
3.12.1. Correct for baseline drift and noise in flame AAS analysis
by subtracting each baseline absorbance reading from its corresponding
working standard or sample absorbance reading to obtain the net
absorbance reading for each standard and sample.
3.12.2. Use a least squares regression program to plot a
concentration-response curve of net absorbance reading (or peak area for
HGA analysis) versus concentration ([micro]g/mL or ng/mL) of cadmium in
each working standard.
3.12.3. Determine the concentration ([micro]g/mL or ng/mL) of
cadmium in each sample from the resulting concentration-response curve.
If the concentration of cadmium in a sample solution is less than three
times the quantitative detection limit [0.04 [micro]g/mL (40 ng/mL) for
the instrumentation used in the validation of the method] and if
consecutive samples were taken on one employee and the sample results
are to be averaged with other samples to determine a single TWA,
reanalyze the sample by AAS-HGA as described in Section 3.11. and report
the AAS-HGA analytical results.
3.12.4. Calculate the total amount ([micro]g or ng) of cadmium in
each sample from the sample solution volume (mL):
W = (C)(sample vol, mL)(DF)
Where:
W = Total cadmium in sample
C = Calculated concentration of cadmium
DF = Dilution Factor (if applicable)
3.12.5. Make a blank correction for each air sample by subtracting
the total amount of cadmium in the corresponding blank sample from the
total amount of cadmium in the sample.
3.12.6. Calculate the concentration of cadmium in an air sample (mg/
m\3\ or [micro]g/m\3\) by using one of the following equations:
mg/m\3\ = Wbc/(Air vol sampled, L)
or
[micro]g/m\3\ = (Wbc)(1,000 ng/[micro]g)/(Air vol sampled, L)
Where:
Wbc = blank corrected total [micro]g cadmium in the sample.
(1[micro]g=1,000 ng)
4. Backup Data
4.1. Introduction
4.1.1. The purpose of this evaluation is to determine the analytical
method recovery, working standard range, and qualitative and
quantitative detection limits of the two atomic absorption analytical
techniques included in this method. The evaluation consisted of the
following experiments:
1. An analysis of 24 samples (six samples each at 0.1, 0.5, 1 and 2
times the TWA-PEL) for the analytical method recovery study of the flame
AAS analytical technique.
2. An analysis of 18 samples (six samples each at 0.5, 1 and 2 times
the Action Level TWA-PEL) for the analytical method recovery study of
the AAS-HGA analytical technique.
3. Multiple analyses of the reagent blank and a series of standard
solutions to determine the working standard range and the
[[Page 179]]
qualitative and quantitative detection limits for both atomic absorption
analytical techniques.
4.1.2. The analytical method recovery results at all test levels
were calculated from concentration-response curves and statistically
examined for outliers at the 99% confidence level. Possible outliers
were determined using the Treatment of Outliers test (5.10.). In
addition, the sample results of the two analytical techniques, at 0.5,
1.0 and 2.0 times their target concentrations, were tested for
homogeneity of variances also at the 99% confidence level. Homogeneity
of the coefficients of variation was determined using the Bartlett's
test (5.11.). The overall analytical error (OAE) at the 95% confidence
level was calculated using the equation (5.12.):
OAE = [[verbar]
Bias[verbar]+(1.96)(CV1(pooled))(100%)]
4.1.3. A derivation of the International Union of Pure and Applied
Chemistry (IUPAC) detection limit equation (5.13.) was used to determine
the qualitative and quantitative detection limits for both atomic
absorption analytical techniques:
Cld = k(sd)/m (Equation 1)
Where:
Cld = the smallest reliable detectable concentration an
analytical instrument can determine at a given confidence
level.
k = 3 for the Qualitative Detection Limit at the 99.86% Confidence Level
= 10 for the Quantitative Detection Limit at the 99.99% Confidence
Level.
sd = standard deviation of the reagent blank (Rbl) readings.
m = analytical sensitivity or slope as calculated by linear regression.
4.1.4. Collection efficiencies of metallic fume and dust atmospheres
on 0.8-[micro]m mixed cellulose ester membrane filters are well
documented and have been shown to be excellent (5.11.). Since elemental
cadmium and the cadmium component of cadmium compounds are nonvolatile,
stability studies of cadmium spiked MCEF samples were not performed.
4.2. Equipment
4.2.1. A Perkin-Elmer (PE) Model 603 spectrophotometer equipped with
a manual gas control system, a stainless steel nebulizer, a burner
mixing chamber, a flow spoiler and a 10 cm. (one-slot) burner head was
used in the experimental validation of the flame AAS analytical
technique. A PE cadmium hollow cathode lamp, operated at the
manufacturer's recommended current setting for continuous operation (4
mA), was used as the source lamp. Instrument parameters are listed in
Attachment 1.
4.2.2. A PE Model 5100 spectrophotometer, Zeeman HGA-600 graphite
furnace atomizer and AS-60 HGA autosampler were used in the experimental
validation of the AAS-HGA analytical technique. The spectrophotometer
was equipped with a PE Series 7700 professional computer and Model PR-
310 printer. A PE System 2 cadmium electrodeless discharge lamp,
operated at the manufacturer's recommended current setting for modulated
operation (170 mA), was used as the source lamp. Instrument parameters
are listed in Attachment 2.
4.3. Reagents
4.3.1. J.T. Baker Chem. Co. (Analyzed grade) concentrated nitric
acid, 69.0-71.0%, and concentrated hydrochloric acid, 36.5-38.0%, were
used to prepare the samples and standards.
4.3.2. Ammonium phosphate, monobasic, NH4 H2
PO4 and magnesium nitrate,
Mg(NO3)26H2 O, both manufactured by the
Mallinckrodt Chem. Co., were used to prepare the matrix modifier for
AAS-HGA analysis.
4.4. Standard Preparation for Flame AAS Analysis
4.4.1. Dilute stock solutions: Prepared 0.01, 0.1, 1, 10 and 100
[micro]g/mL cadmium standard stock solutions by making appropriate
serial dilutions of a commercially available 1,000 [micro]g/mL cadmium
standard stock solution (RICCA Chemical Co., Lot A102) with the
diluting solution (4% HNO3, 0.4% HCl).
4.4.2. Analyzed Standards: Prepared cadmium standards in the range
of 0.001 to 2.0 [micro]g/mL by pipetting 2 to 10 mL of the appropriate
dilute cadmium stock solution into a 100-mL volumetric flask and
diluting to volume with the diluting solution. (See Section 3.7.2.)
4.5. Standard Preparation for AAS-HGA Analysis
4.5.1. Dilute stock solutions: Prepared 1, 10, 100 and 1,000 ng/mL
cadmium standard stock solutions by making appropriate serial dilutions
of a commercially available 1,000 [micro]g/mL cadmium standard stock
solution (J.T. Baker Chemical Co., Instra-analyzed, Lot D22642)
with the diluting solution (4% HNO3, 0.4% HCl).
4.5.2. Analyzed Standards: Prepared cadmium standards in the range
of 0.1 to 40 ng/mL by pipetting 2 to 10 mL of the appropriate dilute
cadmium stock solution into a 100-mL volumetric flask and diluting to
volume with the diluting solution. (See Section 3.8.2.)
4.6. Detection Limits and Standard Working Range for Flame AAS Analysis
4.6.1. Analyzed the reagent blank solution and the entire series of
cadmium standards in the range of 0.001 to 2.0 [micro]g/mL three to six
times according to the instructions given in Section 3.10. The diluting
solution (4% HNO3, 0.4% HCl) was used as the reagent blank.
The
[[Page 180]]
integration time on the PE 603 spectrophotometer was set to 3.0 seconds
and a four-fold expansion of the absorbance reading of the 2.0 [micro]g/
mL cadmium standard was made prior to analysis. The 2.0 [micro]g/mL
standard gave a net absorbance reading of 0.350 abs. units prior to
expansion in agreement with the manufacturer's specifications (5.6.).
4.6.2. The net absorbance readings of the reagent blank and the low
concentration Cd standards from 0.001 to 0.1 [micro]g/mL and the
statistical analysis of the results are shown in Table I. The standard
deviation, sd, of the six net absorbance readings of the reagent blank
is 1.05 abs. units. The slope, m, as calculated by a linear regression
plot of the net absorbance readings (shown in Table II) of the 0.02 to
1.0 [micro]g/mL cadmium standards versus their concentration is 772.7
abs. units/([micro]g/mL).
4.6.3. If these values for sd and the slope, m, are used in Eqn. 1
(Sect. 4.1.3.), the qualitative and quantitative detection limits as
determined by the IUPAC Method are:
Cld=(3)(1.05 abs. units)/(772.7 abs. units/([micro]g/mL))
= 0.0041 [micro]g/mL for the qualitative detection limit.
Cld=(10)(1.05 abs. units)/(772.7 abs. units/[micro]g/mL))
=0.014 [micro]g/mL for the quantitative detection limit.
The qualitative and quantitative detection limits for the flame AAS
analytical technique are 0.041 [micro]g and 0.14 [micro]g cadmium,
respectively, for a 10 mL solution volume. These correspond,
respectively, to 0.2 [micro]g/m\3\ and 0.70 [micro]g/m\3\ for a 200 L
air volume.
4.6.4. The recommended Cd standard working range for flame AAS
analysis is 0.02 to 2.0 [micro]g/mL. The net absorbance readings of the
reagent blank and the recommended working range standards and the
statistical analysis of the results are shown in Table II. The standard
of lowest concentration in the working range, 0.02 [micro]g/mL, is
slightly greater than the calculated quantitative detection limit, 0.014
[micro]g/mL. The standard of highest concentration in the working range,
2.0 [micro]g/mL, is at the upper end of the linear working range
suggested by the manufacturer (5.6.). Although the standard net
absorbance readings are not strictly linear at concentrations above 0.5
[micro]g/mL, the deviation from linearity is only about 10% at the upper
end of the recommended standard working range. The deviation from
linearity is probably caused by the four-fold expansion of the signal
suggested in the method. As shown in Table II, the precision of the
standard net absorbance readings are excellent throughout the
recommended working range; the relative standard deviations of the
readings range from 0.009 to 0.064.
4.7. Detection Limits and Standard Working Range for AAS-HGA Analysis
4.7.1. Analyzed the reagent blank solution and the entire series of
cadmium standards in the range of 0.1 to 40 ng/mL according to the
instructions given in Section 3.11. The diluting solution (4%
HNO3, 0.4% HCl) was used as the reagent blank. A fresh
aliquot of the reagent blank and of each standard was used for every
analysis. The experimental characteristic mass value was 0.41 pg,
calculated from the average peak area (abs-sec) reading of the 5 ng/mL
standard which is approximately midway in the linear portion of the
working standard range. This agreed within 20% with the characteristic
mass value, 0.35 pg, listed by the manufacturer of the instrument
(5.2.).
4.7.2. The peak area (abs-sec) readings of the reagent blank and the
low concentration Cd standards from 0.1 to 2.0 ng/mL and statistical
analysis of the results are shown in Table III. Five of the reagent
blank peak area readings were zero and the sixth reading was 1 and was
an outlier. The near lack of a blank signal does not satisfy a strict
interpretation of the IUPAC method for determining the detection limits.
Therefore, the standard deviation of the six peak area readings of the
0.2 ng/mL cadmium standard, 0.75 abs-sec, was used to calculate the
detection limits by the IUPAC method. The slope, m, as calculated by a
linear regression plot of the peak area (abs-sec) readings (shown in
Table IV) of the 0.2 to 10 ng/mL cadmium standards versus their
concentration is 51.5 abs-sec/(ng/mL).
4.7.3. If 0.75 abs-sec (sd) and 51.5 abs-sec/(ng/mL) (m) are used in
Eqn. 1 (Sect. 4.1.3.), the qualitative and quantitative detection limits
as determined by the IUPAC method are:
Cld = (3)(0.75 abs-sec)/(51.5 abs-sec/(ng/mL)
= 0.044 ng/mL for the qualitative detection limit.
Cld= (10)(0.75 abs-sec)/(51.5 abs-sec/(ng/mL) = 0.15 ng/mL
for the quantitative detection limit.
The qualitative and quantitative detection limits for the AAS-HGA
analytical technique are 0.44 ng and 1.5 ng cadmium, respectively, for a
10 mL solution volume. These correspond, respectively, to 0.007
[micro]g/m\3\ and 0.025 [micro]g/m\3\ for a 60 L air volume.
4.7.4. The peak area (abs-sec) readings of the Cd standards from 0.2
to 40 ng/mL and the statistical analysis of the results are given in
Table IV. The recommended standard working range for AAS-HGA analysis is
0.2 to 20 ng/mL. The standard of lowest concentration in the recommended
working range is slightly greater than the calculated quantitative
detection limit, 0.15 ng/mL. The deviation from linearity of the peak
area readings of the 20 ng/mL standard, the highest concentration
standard in the recommended working range, is approximately
[[Page 181]]
10%. The deviations from linearity of the peak area readings of the 30
and 40 ng/mL standards are significantly greater than 10%. As shown in
Table IV, the precision of the peak area readings are satisfactory
throughout the recommended working range; the relative standard
deviations of the readings range from 0.025 to 0.083.
4.8. Analytical Method Recovery for Flame AAS Analysis
4.8.1. Four sets of spiked MCEF samples were prepared by injecting
20 [micro]L of 10, 50, 100 and 200 [micro]g/mL dilute cadmium stock
solutions on 37 mm diameter filters (part no. AAWP 037 00, Millipore
Corp., Bedford, MA) with a calibrated micropipet. The dilute stock
solutions were prepared by making appropriate serial dilutions of a
commercially available 1,000 [micro]g/mL cadmium standard stock solution
(RICCA Chemical Co., Lot A102) with the diluting solution (4%
HNO3, 0.4% HCl). Each set contained six samples and a sample
blank. The amount of cadmium in the prepared sets were equivalent to
0.1, 0.5, 1.0 and 2.0 times the TWA PEL target concentration of 5
[micro]g/m\3\ for a 400 L air volume.
4.8.2. The air-dried spiked filters were digested and analyzed for
their cadmium content by flame atomic absorption spectroscopy (AAS)
following the procedure described in Section 3. The 0.02 to 2.0[micro]g/
mL cadmium standards (the suggested working range) were used in the
analysis of the spiked filters.
4.8.3. The results of the analysis are given in Table V. One result
at 0.5 times the TWA PEL target concentration was an outlier and was
excluded from statistical analysis. Experimental justification for
rejecting it is that the outlier value was probably due to a spiking
error. The coefficients of variation for the three test levels at 0.5 to
2.0 times the TWA PEL target concentration passed the Bartlett's test
and were pooled.
4.8.4. The average recovery of the six spiked filter samples at 0.1
times the TWA PEL target concentration was 118.2% with a coefficient of
variation (CV1) of 0.128. The average recovery of the spiked
filter samples in the range of 0.5 to 2.0 times the TWA target
concentration was 104.0% with a pooled coefficient of variation
(CV1) of 0.010. Consequently, the analytical bias found in
these spiked sample results over the tested concentration range was
+4.0% and the OAE was 6.0%.
4.9. Analytical Method Recovery for AAS-HGA Analysis
4.9.1. Three sets of spiked MCEF samples were prepared by injecting
15[micro]L of 5, 10 and 20 [micro]g/mL dilute cadmium stock solutions on
37 mm diameter filters (part no. AAWP 037 00, Millipore Corp., Bedford,
MA) with a calibrated micropipet. The dilute stock solutions were
prepared by making appropriate serial dilutions of a commercially
available certified 1,000 [micro]g/mL cadmium standard stock solution
(Fisher Chemical Co., Lot 913438-24) with the diluting solution
(4% HNO3, 0.4% HCl). Each set contained six samples and a
sample blank. The amount of cadmium in the prepared sets were equivalent
to 0.5, 1 and 2 times the Action Level TWA target concentration of 2.5
[micro]g/m\3\ for a 60 L air volume.
4.9.2. The air-dried spiked filters were digested and analyzed for
their cadmium content by flameless atomic absorption spectroscopy using
a heated graphite furnace atomizer following the procedure described in
Section 3. A five-fold dilution of the spiked filter samples at 2 times
the Action Level TWA was made prior to their analysis. The 0.05 to 20
ng/mL cadmium standards were used in the analysis of the spiked filters.
4.9.3. The results of the analysis are given in Table VI. There were
no outliers. The coefficients of variation for the three test levels at
0.5 to 2.0 times the Action Level TWA PEL passed the Bartlett's test and
were pooled. The average recovery of the spiked filter samples was 94.2%
with a pooled coefficient of variation (CV1) of 0.043.
Consequently, the analytical bias was -5.8% and the OAE was 14.2%.
4.10. Conclusions
The experiments performed in this evaluation show the two atomic
absorption analytical techniques included in this method to be precise
and accurate and have sufficient sensitivity to measure airborne cadmium
over a broad range of exposure levels and sampling periods.
5. References
5.1. Slavin, W. Graphite Furnace AAS--A Source Book; Perkin-Elmer
Corp., Spectroscopy Div.: Ridgefield, CT, 1984; p. 18 and pp. 83-90.
5.2. Grosser, Z., Ed.; Techniques in Graphite Furnace Atomic
Absorption Spectrophotometry; Perkin-Elmer Corp., Spectroscopy Div.:
Ridgefield, CT, 1985.
5.3. Occupational Safety and Health Administration Salt Lake
Technical Center: Metal and Metalloid Particulate in Workplace
Atmospheres (Atomic Absorption) (USDOL/OSHA Method No. ID-121). In OSHA
Analytical Methods Manual 2nd ed. Cincinnati, OH: American Conference of
Governmental Industrial Hygienists, 1991.
5.4. Occupational Safety and Health Administration Salt Lake
Technical Center: Metal and Metalloid Particulate in Workplace
Atmospheres (ICP) (USDOL/OSHA Method No. ID-125G). In OSHA Analytical
Methods Manual 2nd ed. Cincinnati, OH:
[[Page 182]]
American Conference of Governmental Industrial Hygienists, 1991.
5.5. Windholz, M., Ed.; The Merck Index, 10th ed.; Merck & Co.:
Rahway, NJ, 1983.
5.6. Analytical Methods for Atomic Absorption Spectrophotometry, The
Perkin-Elmer Corporation: Norwalk, CT, 1982.
5.7. Slavin, W., D.C. Manning, G. Carnrick, and E. Pruszkowska:
Properties of the Cadmium Determination with the Platform Furnace and
Zeeman Background Correction. Spectrochim. Acta 38B:1157-1170 (1983).
5.8. Occupational Safety and Health Administration Salt Lake
Technical Center: Standard Operating Procedure for Atomic Absorption.
Salt Lake City, UT: USDOL/OSHA-SLTC, In progress.
5.9. Occupational Safety and Health Administration Salt Lake
Technical Center: AAS-HGA Standard Operating Procedure. Salt Lake City,
UT: USDOL/OSHA-SLTC, In progress.
5.10. Mandel, J.: Accuracy and Precision, Evaluation and
Interpretation of Analytical Results, The Treatment of Outliers. In
Treatise On Analytical Chemistry, 2nd ed., Vol.1, edited by I. M.
Kolthoff and P. J. Elving. New York: John Wiley and Sons, 1978. pp. 282-
285.
5.11. National Institute for Occupational Safety and Health:
Documentation of the NIOSH Validation Tests by D. Taylor, R. Kupel, and
J. Bryant (DHEW/NIOSH Pub. No. 77-185). Cincinnati, OH: National
Institute for Occupational Safety and Health, 1977.
5.12. Occupational Safety and Health Administration Analytical
Laboratory: Precision and Accuracy Data Protocol for Laboratory
Validations. In OSHA Analytical Methods Manual 1st ed. Cincinnati, OH:
American Conference of Governmental Industrial Hygienists (Pub. No.
ISBN: 0-936712-66-X), 1985.
5.13. Long, G.L. and J.D. Winefordner: Limit of Detection--A Closer
Look at the IUPAC Definition. Anal.Chem. 55:712A-724A (1983).
5.14. American Conference of Governmental Industrial Hygienists:
Documentation of Threshold Limit Values and Biological Exposure Indices.
5th ed. Cincinnati, OH: American Conference of Governmental Industrial
Hygienists, 1986.
Table I--Cd Detection Limit Study
[Flame AAS Analysis]
------------------------------------------------------------------------
Absorbance
STD ([micro]g/mL) reading at 228.8 Statistical
nm analysis
------------------------------------------------------------------------
Reagent blank................... 5 2 n=6.
4 3 mean=3.50.
4 3 std dev=1.05.
CV=0.30.
0.001........................... 6 6 n=6.
2 4 mean=5.00.
6 6 std dev=1.67.
CV=0.335.
0.002........................... 5 7 n=6.
7 3 mean=5.50.
7 4 std dev=1.76.
CV=0.320.
0.005........................... 7 7 n=6.
8 8 mean=7.33.
8 6 std dev=0.817.
CV=0.111.
0.010........................... 10 9 n=6.
10 13 mean=10.3.
10 10 std dev=1.37.
CV=0.133.
0.020........................... 20 23 n=6.
20 22 mean=20.8.
20 20 std dev=1.33.
CV=0.064.
0.050........................... 42 42 n=6.
42 42 mean=42.5.
42 45 std dev=1.22.
CV=0.029.
0.10............................ 84 n=3.
80 mean=82.3.
83 std dev=2.08.
CV=0.025.
------------------------------------------------------------------------
Table II--Cd Standard Working Range Study
[Flame AAS Analysis]
------------------------------------------------------------------------
Absorbance
STD ([micro]g/mL) reading at 228.8 Statistical
nm analysis
------------------------------------------------------------------------
Reagent blank................... 5 2 n=6.
4 3 mean=3.50.
4 3 std dev=1.05.
CV=0.30.
0.020........................... 20 23 n=6.
20 22 mean=20.8.
20 20 std dev=1.33.
CV=0.064.
0.050........................... 42 42 n=6.
42 42 mean=42.5.
42 45 std dev=1.22.
CV=0.029.
0.10............................ 84 n=3.
80 mean=82.3.
83 std dev=2.08.
CV=0.025.
0.20............................ 161 n=3.
161 mean=160.0.
158 std dev=1.73.
CV=0.011.
0.50............................ 391 n=3.
389 mean=391.0.
393 std dev=2.00.
CV=0.005.
1.00............................ 760 n=3.
748 mean=753.3.
752 std dev=6.11.
CV=0.008.
2.00............................ 1416 n=3.
1426 mean=1414.3.
1401 std dev=12.6.
CV=0.009.
------------------------------------------------------------------------
[[Page 183]]
Table III--Cd Detection Limit Study
[AAS-HGA Analysis]
------------------------------------------------------------------------
Peak area
readings x
STD (ng/mL) 10\3\ at Statistical analysis
228.8 nm
------------------------------------------------------------------------
Reagent blank...................... 0 0 n=6.
0 1 mean=0.167.
0 0 std dev=0.41.
CV=2.45.
0.1................................ 8 6 n=6.
5 7 mean=7.7.
13 7 std dev=2.8.
CV=0.366.
0.2................................ 11 13 n=6.
11 12 mean=11.8.
12 12 std dev=0.75.
CV=0.064.
0.5................................ 28 33 n=6.
26 28 mean=28.8.
28 30 std dev=2.4.
CV=0.083.
1.0................................ 52 55 n=6.
56 58 mean=54.8.
54 54 std dev=2.0.
CV=0.037.
2.0................................ 101 112 n=6.
110 110 mean=108.8.
110 110 std dev=3.9.
CV=0.036.
------------------------------------------------------------------------
Table IV--Cd Standard Working Range Study
[AAS-HGA Analysis]
------------------------------------------------------------------------
Peak area
readings x
STD (ng/mL) 10\3\ at Statistical analysis
228.8 nm
------------------------------------------------------------------------
0.2................................ 11 13 n=6.
11 12 mean=11.8.
12 12 std dev=0.75.
CV=0.064.
0.5................................ 28 33 n=6.
26 28 mean=28.8.
28 30 std dev=2.4.
CV=0.083.
1.0................................ 52 55 n=6.
56 58 mean=54.8.
54 54 std dev=2.0.
CV=0.037.
2.0................................ 101 112 n=6.
110 110 mean=108.8.
110 110 std dev=3.9.
CV=0.036.
5.0................................ 247 265 n=6.
268 275 mean=265.5.
259 279 std dev=11.5.
CV=0.044.
10.0............................... 495 520 n=6.
523 513 mean=516.7.
516 533 std dev=12.7.
CV=0.025.
20.0............................... 950 953 n=6.
951 958 mean=941.8.
949 890 std dev=25.6.
CV=0.027.
30.0............................... 1269 1291 n=6.
1303 1307 mean=1293.
1295 1290 std dev=13.3.
CV=0.010.
40.0............................... 1505 1567 n=6.
1535 1567 mean=1552.
1566 1572 std dev=26.6.
CV=0.017.
------------------------------------------------------------------------
Table V--Analytical Method Recovery
[Flame AAS Analysis]
----------------------------------------------------------------------------------------------------------------
Test level 0.5x 1.0x 2.0x
--------------------------------------- Percent [micro]g ---------- Percent [micro]g ---------- Percent
[micro]g rec. taken [micro]g rec. taken [micro]g rec.
[micro]g taken found found found
----------------------------------------------------------------------------------------------------------------
1.00........................ 1.0715 107.2 2.00 2.0688 103.4 4.00 4.1504 103.8
1.00........................ 1.0842 108.4 2.00 2.0174 100.9 4.00 4.1108 102.8
1.00........................ 1.0842 108.4 2.00 2.0431 102.2 4.00 4.0581 101.5
1.00........................ *1.0081 *100.8 2.00 2.0431 102.2 4.00 4.0844 102.1
1.00........................ 1.0715 107.2 2.00 2.0174 100.9 4.00 4.1504 103.8
1.00........................ 1.0842 108.4 2.00 2.0045 100.2 4.00 4.1899 104.7
----------------------------------------------------------------------------------------------------------------
n= ........ 5 ........ ........ 6 ........ ........ 6
mean= ........ 107.9 ........ ........ 101.6 ........ ........ 103.1
std dev= ........ 0.657 ........ ........ 1.174 ........ ........ 1.199
CV1= ........ 0.006 ........ ........ 0.011 ........ ........ 0.012
CV1 (pooled)=0.010
* Rejected as an outlier--this value did not pass the outlier T-test at the 99% confidence level.
------------------------------------------------------------------------
Test level 0.1x
-------------------------------------------------------- Percent rec.
[micro]g taken [micro]g found
------------------------------------------------------------------------
0.200............................... 0.2509 125.5
0.200............................... 0.2509 125.5
0.200............................... 0.2761 138.1
[[Page 184]]
0.200............................... 0.2258 112.9
0.200............................... 0.2258 112.9
0.200............................... 0.1881 94.1
------------------------------------------------------------------------
n=.................................. ................. 6
mean=............................... ................. 118.2
std dev=............................ ................. 15.1
CV1=................................ ................. 0.128
Table VI--Analytical Method Recovery
[AAS-HGA analysis]
----------------------------------------------------------------------------------------------------------------
Test level 0.5x 1.0x 2.0x
---------------------------------------------- Percent ng ---------- Percent ng ---------- Percent
ng rec. taken rec. taken rec.
ng taken found ng found ng found
----------------------------------------------------------------------------------------------------------------
75.................................. 71.23 95.0 150 138.00 92.0 300 258.43 86.1
75.................................. 71.47 95.3 150 138.29 92.2 300 258.46 86.2
75.................................. 70.02 93.4 150 136.30 90.9 300 280.55 93.5
75.................................. 77.34 103.1 150 146.62 97.7 300 288.34 96.1
75.................................. 78.32 104.4 150 145.17 96.8 300 261.74 87.2
75.................................. 71.96 95.9 150 144.88 96.6 300 277.22 92.4
----------------------------------------------------------------------------------------------------------------
n= ........ 6 ........ ........ 6 ........ ........ 6
mean= ........ 97.9 ........ ........ 94.4 ........ ........ 90.3
std dev= ........ 4.66 ........ ........ 2.98 ........ ........ 4.30
CV1= ........ 0.048 ........ ........ 0.032 ........ ........ 0.048
CV1(pooled)=0.043
Attachment 1
Instrumental Parameters for Flame AAS Analysis
Atomic Absorption Spectrophotometer (Perkin-Elmer Model 603)
Flame: Air/Acetylene--lean, blue
Oxidant Flow: 55
Fuel Flow: 32
Wavelength: 228.8 nm
Slit: 4 (0.7 nm)
Range: UV
Signal: Concentration (4 exp)
Integration Time: 3 sec
Attachment 2
Instrumental Parameters for HGA Analysis
Atomic Absorption Spectrophotometer (Perkin-Elmer Model 5100)
Signal Type: Zeeman AA
Slitwidth: 0.7 nm
Wavelength: 228.8 nm
Measurement: Peak Area
Integration Time: 6.0 sec
BOC Time: 5 sec
BOC=Background Offset Correction.
Zeeman Graphite Furnace (Perkin-Elmer Model HGA-600)
----------------------------------------------------------------------------------------------------------------
Ramp time Hold time Temp. Argon flow
Step (sec) (sec) ([deg]C) (mL/min) Read (sec)
----------------------------------------------------------------------------------------------------------------
1) Predry........................................... 5 10 90 300
2) Dry.............................................. 30 10 140 300
3) Char............................................. 10 20 900 300
4) Cool Down........................................ 1 8 30 300
5) Atomize.......................................... 0 5 1600 0 -1
6) Burnout.......................................... 1 8 2500 300 ..........
----------------------------------------------------------------------------------------------------------------
[[Page 185]]
Appendix F toSec. 1910.1027--Nonmandatory Protocol for Biological
Monitoring
1.00 Introduction
Under the final OSHA cadmium rule (29 CFR part 1910), monitoring of
biological specimens and several periodic medical examinations are
required for eligible employees. These medical examinations are to be
conducted regularly, and medical monitoring is to include the periodic
analysis of cadmium in blood (CDB), cadmium in urine (CDU) and beta-2-
microglobulin in urine (B2MU). As CDU and B2MU are to be normalized to
the concentration of creatinine in urine (CRTU), then CRTU must be
analyzed in conjunction with CDU and B2MU analyses.
The purpose of this protocol is to provide procedures for
establishing and maintaining the quality of the results obtained from
the analyses of CDB, CDU and B2MU by commercial laboratories.
Laboratories conforming to the provisions of this nonmandatory protocol
shall be known as ``participating laboratories.'' The biological
monitoring data from these laboratories will be evaluated by physicians
responsible for biological monitoring to determine the conditions under
which employees may continue to work in locations exhibiting airborne-
cadmium concentrations at or above defined actions levels (see
paragraphs (l)(3) and (l)(4) of the final rule). These results also may
be used to support a decision to remove workers from such locations.
Under the medical monitoring program for cadmium, blood and urine
samples must be collected at defined intervals from workers by
physicians responsible for medical monitoring; these samples are sent to
commerical laboratories that perform the required analyses and report
results of these analyses to the responsible physicians. To ensure the
accuracy and reliability of these laboratory analyses, the laboratories
to which samples are submitted should participate in an ongoing and
efficacious proficiency testing program. Availability of proficiency
testing programs may vary with the analyses performed.
To test proficiency in the analysis of CDB, CDU and B2MU, a
laboratory should participate either in the interlaboratory comparison
program operated by the Centre de Toxicologie du Quebec (CTQ) or an
equivalent program. (Currently, no laboratory in the U.S. performs
proficiency testing on CDB, CDU or B2MU.) Under this program, CTQ sends
participating laboratories 18 samples of each analyte (CDB, CDU and/or
B2MU) annually for analysis. Participating laboratories must return the
results of these analyses to CTQ within four to five weeks after
receiving the samples.
The CTQ program pools analytical results from many participating
laboratories to derive consensus mean values for each of the samples
distributed. Results reported by each laboratory then are compared
against these consensus means for the analyzed samples to determine the
relative performance of each laboratory. The proficiency of a
participating laboratory is a function of the extent of agreement
between results submitted by the participating laboratory and the
consensus values for the set of samples analyzed.
Proficiency testing for CRTU analysis (which should be performed
with CDU and B2MU analyses to evaluate the results properly) also is
recommended. In the U.S., only the College of American Pathologists
(CAP) currently conducts CRTU proficiency testing; participating
laboratories should be accredited for CRTU analysis by the CAP.
Results of the proficiency evaluations will be forwarded to the
participating laboratory by the proficiency-testing laboratory, as well
as to physicians designated by the participating laboratory to receive
this information. In addition, the participating laboratory should, on
request, submit the results of their internal Quality Assurance/Quality
Control (QA/QC) program for each analytic procedure (i.e., CDB, CDU and/
or B2MU) to physicians designated to receive the proficiency results.
For participating laboratories offering CDU and/or B2MU analyses, QA/QC
documentation also should be provided for CRTU analysis. (Laboratories
should provide QA/QC information regarding CRTU analysis directly to the
requesting physician if they perform the analysis in-house; if CRTU
analysis is performed by another laboratory under contract, this
information should be provided to the physician by the contract
laboratory.)
QA/QC information, along with the actual biological specimen
measurements, should be provided to the responsible physician using
standard formats. These physicians then may collate the QA/QC
information with proficiency test results to compare the relative
performance of laboratories, as well as to facilitate evaluation of the
worker monitoring data. This information supports decisions made by the
physician with regard to the biological monitoring program, and for
mandating medical removal.
This protocol describes procedures that may be used by the
responsible physicians to identify laboratories most likely to be
proficient in the analysis of samples used in the biological monitoring
of cadmium; also provided are procedures for record keeping and
reporting by laboratories participating in proficiency testing programs,
and recommendations to assist these physicians in interpreting
analytical results determined by participating laboratories. As the
collection and handling of samples affects the quality of the data,
recommendations are
[[Page 186]]
made for these tasks. Specifications for analytical methods to be used
in the medical monitoring program are included in this protocol as well.
In conclusion, this document is intended as a supplement to
characterize and maintain the quality of medical monitoring data
collected under the final cadmium rule promulgated by OSHA (29 CFR part
1910). OSHA has been granted authority under the Occupational Safety and
Health Act of 1970 to protect workers from the effects of exposure to
hazardous substances in the work place and to mandate adequate
monitoring of workers to determine when adverse health effects may be
occurring. This nonmandatory protocol is intended to provide guidelines
and recommendations to improve the accuracy and reliability of the
procedures used to analyze the biological samples collected as part of
the medical monitoring program for cadmium.
2.0 Definitions
When the terms below appear in this protocol, use the following
definitions.
Accuracy: A measure of the bias of a data set. Bias is a systematic
error that is either inherent in a method or caused by some artifact or
idiosyncracy of the measurement system. Bias is characterized by a
consistent deviation (positive or negative) in the results from an
accepted reference value.
Arithmetic Mean: The sum of measurements in a set divided by the
number of measurements in a set.
Blind Samples: A quality control procedure in which the
concentration of analyte in the samples should be unknown to the analyst
at the time that the analysis is performed.
Coefficient of Variation: The ratio of the standard deviation of a
set of measurements to the mean (arithmetic or geometric) of the
measurements.
Compliance Samples: Samples from exposed workers sent to a
participating laboratory for analysis.
Control Charts: Graphic representations of the results for quality
control samples being analyzed by a participating laboratory.
Control Limits: Statistical limits which define when an analytic
procedure exceeds acceptable parameters; control limits provide a method
of assessing the accuracy of analysts, laboratories, and discrete
analytic runs.
Control Samples: Quality control samples.
F/T: The measured amount of an analyte divided by the theoretical
value (defined below) for that analyte in the sample analyzed; this
ratio is a measure of the recovery for a quality control sample.
Geometric Mean: The natural antilog of the mean of a set of natural
log-transformed data.
Geometric Standard Deviation: The antilog of the standard deviation
of a set of natural log-transformed data.
Limit of Detection: Using a predefined level of confidence, this is
the lowest measured value at which some of the measured material is
likely to have come from the sample.
Mean: A central tendency of a set of data; in this protocol, this
mean is defined as the arithmetic mean (see definition of arithmetic
mean above) unless stated otherwise.
Performance: A measure of the overall quality of data reported by a
laboratory.
Pools: Groups of quality-control samples to be established for each
target value (defined below) of an analyte. For the protocol provided in
attachment 3, for example, the theoretical value of the quality control
samples of the pool must be within a range defined as plus or minus
() 50% of the target value. Within each analyte
pool, there must be quality control samples of at least 4 theoretical
values.
Precision: The extent of agreement between repeated, independent
measurements of the same quantity of an analyte.
Proficiency: The ability to satisfy a specified level of analyte
performance.
Proficiency Samples: Specimens, the values of which are unknown to
anyone at a participating laboratory, and which are submitted by a
participating laboratory for proficiency testing.
Quality or Data Quality: A measure of the confidence in the
measurement value.
Quality Control (QC) Samples: Specimens, the value of which is
unknown to the analyst, but is known to the appropriate QA/QC personnel
of a participating laboratory; when used as part of a laboratory QA/QC
program, the theoretical values of these samples should not be known to
the analyst until the analyses are complete. QC samples are to be run in
sets consisting of one QC sample from each pool (see definition of
``pools'' above).
Sensitivity: For the purposes of this protocol, the limit of
detection.
Standard Deviation: A measure of the distribution or spread of a
data set about the mean; the standard deviation is equal to the positive
square root of the variance, and is expressed in the same units as the
original measurements in the data set.
Standards: Samples with values known by the analyst and used to
calibrate equipment and to check calibration throughout an analytic run.
In a laboratory QA/QC program, the values of the standards must exceed
the values obtained for compliance samples such that the lowest standard
value is near the limit of detection and the highest standard is higher
than the highest compliance sample or QC sample. Standards of at least
three different values are to be used for calibration, and should be
constructed from at least 2 different sources.
[[Page 187]]
Target Value: Those values of CDB, CDU or B2MU which trigger some
action as prescribed in the medical surveillance section of the
regulatory text of the final cadmium rule. For CDB, the target values
are 5, 10 and 15 [micro]g/l. For CDU, the target values are 3, 7, and 15
[micro]g/g CRTU. For B2 MU, the target values are 300, 750
and 1500 [micro]g/g CRTU. (Note that target values may vary as a
function of time.)
Theoretical Value (or Theoretical Amount): The reported
concentration of a quality-control sample (or calibration standard)
derived from prior characterizations of the sample.
Value or Measurement Value: The numerical result of a measurement.
Variance: A measure of the distribution or spread of a data set
about the mean; the variance is the sum of the squares of the
differences between the mean and each discrete measurement divided by
one less than the number of measurements in the data set.
3.0 Protocol
This protocol provides procedures for characterizing and maintaining
the quality of analytic results derived for the medical monitoring
program mandated for workers under the final cadmium rule.
3.1 Overview
The goal of this protocol is to assure that medical monitoring data
are of sufficient quality to facilitate proper interpretation. The data
quality objectives (DQOs) defined for the medical monitoring program are
summarized in Table 1. Based on available information, the DQOs
presented in Table 1 should be achievable by the majority of
laboratories offering the required analyses commercially; OSHA
recommends that only laboratories meeting these DQOs be used for the
analysis of biological samples collected for monitoring cadmium
exposure.
Table 1--Recommended Data Quality Objectives (DQOs) for the Cadmium Medical Monitoring Program
----------------------------------------------------------------------------------------------------------------
Precision
Analyte/concentration pool Limit of detection (CV) (%) Accuracy
----------------------------------------------------------------------------------------------------------------
Cadmium in blood................. 0.5 [micro]g/l...... ........... 1 [micro]g/l or 15%
of the mean.
<=2 [micro]g/l............... .................... 40
2[micro]g/l....... .................... 20
Cadmium in urine................. 0.5 [micro]g/g ........... 1 [micro]g/l or 15%
creatinine. of the mean.
<=2 [micro]g/l creatinine.... .................... 40
2[micro]g/l .................... 20
creatinine.
[beta]-2-microglobulin in urine: 100 [micro]g/g 5 15% of the mean.
100 [micro]g/g creatine. creatinine.
----------------------------------------------------------------------------------------------------------------
To satisfy the DQOs presented in Table 1, OSHA provides the
following guidelines:
1. Procedures for the collection and handling of blood and urine are
specified (Section 3.4.1 of this protocol);
2. Preferred analytic methods for the analysis of CDB, CDU and B2MU
are defined (and a method for the determination of CRTU also is
specified since CDU and B2MU results are to be normalized to the level
of CRTU).
3. Procedures are described for identifying laboratories likely to
provide the required analyses in an accurate and reliable manner;
4. These guidelines (Sections 3.2.1 to 3.2.3, and Section 3.3)
include recommendations regarding internal QA/QC programs for
participating laboratories, as well as levels of proficiency through
participation in an interlaboratory proficiency program;
5. Procedures for QA/QC record keeping (Section 3.3.2), and for
reporting QC/QA results are described (Section 3.3.3); and,
6. Procedures for interpreting medical monitoring results are
specified (Section 3.4.3).
Methods recommended for the biological monitoring of eligible
workers are:
1. The method of Stoeppler and Brandt (1980) for CDB determinations
(limit of detection: 0.5 [micro]g/l);
2. The method of Pruszkowska et al. (1983) for CDU determinations
(limit of detection: 0.5 [micro]g/l of urine); and,
3. The Pharmacia Delphia test kit (Pharmacia 1990) for the
determination of B2MU (limit of detection: 100 [micro]g/l urine).
Because both CDU and B2MU should be reported in [micro]g/g CRTU, an
independent determination of CRTU is recommended. Thus, both the OSHA
Salt Lake City Technical Center (OSLTC) method (OSHA, no date) and the
Jaffe method (Du Pont, no date) for the determination of CRTU are
specified under this protocol (i.e., either of these 2 methods may be
used). Note that although detection limits are not reported for either
of these CRTU methods, the range of measurements expected for CRTU (0.9-
1.7 [micro]g/l) are well above the likely limit of detection for either
of these methods (Harrison, 1987).
Laboratories using alternate methods should submit sufficient data
to the responsible physicians demonstrating that the alternate method is
capable of satisfying the
[[Page 188]]
defined data quality objectives of the program. Such laboratories also
should submit a QA/QC plan that documents the performance of the
alternate method in a manner entirely equivalent to the QA/QC plans
proposed in Section 3.3.1.
3.2 Duties of the Responsible Physician
The responsible physician will evaluate biological monitoring
results provided by participating laboratories to determine whether such
laboratories are proficient and have satisfied the QA/QC
recommendations. In determining which laboratories to employ for this
purpose, these physicians should review proficiency and QA/QC data
submitted to them by the participating laboratories.
Participating laboratories should demonstrate proficiency for each
analyte (CDU, CDB and B2MU) sampled under the biological monitoring
program. Participating laboratories involved in analyzing CDU and B2MU
also should demonstrate proficiency for CRTU analysis, or provide
evidence of a contract with a laboratory proficient in CRTU analysis.
3.2.1 Recommendations for Selecting Among Existing Laboratories
OSHA recommends that existing laboratories providing commercial
analyses for CDB, CDU and/or B2MU for the medical monitoring program
satisfy the following criteria:
1. Should have performed commercial analyses for the appropriate
analyte (CDB, CDU and/or B2MU) on a regular basis over the last 2 years;
2. Should provide the responsible physician with an internal QA/QC
plan;
3. If performing CDU or B2MU analyses, the participating laboratory
should be accredited by the CAP for CRTU analysis, and should be
enrolled in the corresponding CAP survey (note that alternate
credentials may be acceptable, but acceptability is to be determined by
the responsible physician); and,
4. Should have enrolled in the CTQ interlaboratory comparison
program for the appropriate analyte (CDB, CDU and/or B2MU).
Participating laboratories should submit appropriate documentation
demonstrating compliance with the above criteria to the responsible
physician. To demonstrate compliance with the first of the above
criteria, participating laboratories should submit the following
documentation for each analyte they plan to analyze (note that each
document should cover a period of at least 8 consecutive quarters, and
that the period designated by the term ``regular analyses'' is at least
once a quarter):
1. Copies of laboratory reports providing results from regular
analyses of the appropriate analyte (CDB, CDU and/or B2MU);
2. Copies of 1 or more signed and executed contracts for the
provision of regular analyses of the appropriate analyte (CDB, CDU and/
or B2MU); or,
3. Copies of invoices sent to 1 or more clients requesting payment
for the provision of regular analyses of the appropriate analyte (CDB,
CDU and/or B2MU). Whatever the form of documentation submitted, the
specific analytic procedures conducted should be identified directly.
The forms that are copied for submission to the responsible physician
also should identify the laboratory which provided these analyses.
To demonstrate compliance with the second of the above criteria, a
laboratory should submit to the responsible physician an internal QA/QC
plan detailing the standard operating procedures to be adopted for
satisfying the recommended QA/QC procedures for the analysis of each
specific analyte (CDB, CDU and/or B2MU). Procedures for internal QA/QC
programs are detailed in Section 3.3.1 below.
To satisfy the third of the above criteria, laboratories analyzing
for CDU or B2MU also should submit a QA/QC plan for creatinine analysis
(CRTU); the QA/QC plan and characterization analyses for CRTU must come
from the laboratory performing the CRTU analysis, even if the CRTU
analysis is being performed by a contract laboratory.
Laboratories enrolling in the CTQ program (to satisfy the last of
the above criteria) must remit, with the enrollment application, an
initial fee of approximately $100 per analyte. (Note that this fee is
only an estimate, and is subject to revision without notice.)
Laboratories should indicate on the application that they agree to have
proficiency test results sent by the CTQ directly to the physicians
designated by participating laboratories.
Once a laboratory's application is processed by the CTQ, the
laboratory will be assigned a code number which will be provided to the
laboratory on the initial confirmation form, along with identification
of the specific analytes for which the laboratory is participating.
Confirmation of participation will be sent by the CTQ to physicians
designated by the applicant laboratory.
3.2.2 Recommended Review of Laboratories Selected To Perform Analyses
Six months after being selected initially to perform analyte
determinations, the status of participating laboratories should be
reviewed by the responsible physicians. Such reviews should then be
repeated every 6 months or whenever additional proficiency or QA/QC
documentation is received (whichever occurs first).
As soon as the responsible physician has received the CTQ results
from the first 3 rounds of proficiency testing (i.e., 3 sets of 3
samples each for CDB, CDU and/or B2MU) for
[[Page 189]]
a participating laboratory, the status of the laboratory's continued
participation should be reviewed. Over the same initial 6-month period,
participating laboratories also should provide responsible physicians
the results of their internal QA/QC monitoring program used to assess
performance for each analyte (CDB, CDU and/or B2MU) for which the
laboratory performs determinations. This information should be submitted
using appropriate forms and documentation.
The status of each participating laboratory should be determined for
each analyte (i.e., whether the laboratory satisfies minimum proficiency
guidelines based on the proficiency samples sent by the CTQ and the
results of the laboratory's internal QA/QC program). To maintain
competency for analysis of CDB, CDU and/or B2MU during the first review,
the laboratory should satisfy performance requirements for at least 2 of
the 3 proficiency samples provided in each of the 3 rounds completed
over the 6-month period. Proficiency should be maintained for the
analyte(s) for which the laboratory conducts determinations.
To continue participation for CDU and/or B2MU analyse, laboratories
also should either maintain accreditation for CRTU analysis in the CAP
program and participate in the CAP surveys, or they should contract the
CDU and B2MU analyses to a laboratory which satisfies these requirements
(or which can provide documentation of accreditation/participation in an
equivalent program).
The performance requirement for CDB analysis is defined as an
analytical result within 1 [micro]g/l blood or 15%
of the consensus mean (whichever is greater). For samples exhibiting a
consensus mean less than 1 [micro]g/l, the performance requirement is
defined as a concentration between the detection limit of the analysis
and a maximum of 2 [micro]g/l. The purpose for redefining the acceptable
interval for low CDB values is to encourage proper reporting of the
actual values obtained during measurement; laboratories, therefore, will
not be penalized (in terms of a narrow range of acceptability) for
reporting measured concentrations smaller than 1 [micro]g/l.
The performance requirement for CDU analysis is defined as an
analytical result within 1 [micro]g/l urine or 15%
of the consensus mean (whichever is greater). For samples exhibiting a
consensus mean less than 1 [micro]g/l urine, the performance requirement
is defined as a concentration between the detection limit of the
analysis and a maximum of 2 [micro]g/l urine. Laboratories also should
demonstrate proficiency in creatinine analysis as defined by the CAP.
Note that reporting CDU results, other than for the CTQ proficiency
samples (i.e., compliance samples), should be accompanied with results
of analyses for CRTU, and these 2 sets of results should be combined to
provide a measure of CDU in units of [micro]g/g CRTU.
The performance requirement for B2MU is defined as analytical
results within 15% of the consensus mean. Note
that reporting B2MU results, other than for CTQ proficiency samples
(i.e., compliance samples), should be accompanied with results of
analyses for CRTU, and these 2 sets of results should be combined to
provide a measure of B2MU in units of [micro]g/g CRTU.
There are no recommended performance checks for CRTU analyses. As
stated previously, laboratories performing CRTU analysis in support of
CDU or B2MU analyses should be accredited by the CAP, and participating
in the CAP's survey for CRTU.
Following the first review, the status of each participating
laboratory should be reevaluated at regular intervals (i.e.,
corresponding to receipt of results from each succeeding round of
proficiency testing and submission of reports from a participating
laboratory's internal QA/QC program).
After a year of collecting proficiency test results, the following
proficiency criterion should be added to the set of criteria used to
determine the participating laboratory's status (for analyzing CDB, CDU
and/or B2MU): A participating laboratory should not fail performance
requirements for more than 4 samples from the 6 most recent consecutive
rounds used to assess proficiency for CDB, CDU and/or B2MU separately
(i.e., a total of 18 discrete proficiency samples for each analyte).
Note that this requirement does not replace, but supplements, the
recommendation that a laboratory should satisfy the performance criteria
for at least 2 of the 3 samples tested for each round of the program.
3.2.3 Recommendations for Selecting Among Newly-Formed Laboratories (or
Laboratories That Previously Failed To Meet the Protocol Guidelines)
OSHA recommends that laboratories that have not previously provided
commercial analyses of CDB, CDU and/or B2MU (or have done so for a
period less than 2 years), or which have provided these analyses for 2
or more years but have not conformed previously with these protocol
guidelines, should satisfy the following provisions for each analyte for
which determinations are to be made prior to being selected to analyze
biological samples under the medical monitoring program:
1. Submit to the responsible physician an internal QA/QC plan
detailing the standard operating procedures to be adopted for satisfying
the QA/QC guidelines (guidelines for internal QA/QC programs are
detailed in Section 3.3.1);
2. Submit to the responsible physician the results of the initial
characterization analyses for each analyte for which determinations are
to be made;
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3. Submit to the responsible physician the results, for the initial
6-month period, of the internal QA/QC program for each analyte for which
determinations are to be made (if no commercial analyses have been
conducted previously, a minimum of 2 mock standardization trials for
each analyte should be completed per month for a 6-month period);
4. Enroll in the CTQ program for the appropriate analyte for which
determinations are to be made, and arrange to have the CTQ program
submit the initial confirmation of participation and proficiency test
results directly to the designated physicians. Note that the designated
physician should receive results from 3 completed rounds from the CTQ
program before approving a laboratory for participation in the
biological monitoring program;
5. Laboratories seeking participation for CDU and/or B2MU analyses
should submit to the responsible physician documentation of
accreditation by the CAP for CRTU analyses performed in conjunction with
CDU and/or B2MU determinations (if CRTU analyses are conducted by a
contract laboratory, this laboratory should submit proof of CAP
accreditation to the responsible physician); and,
6. Documentation should be submitted on an appropriate form.
To participate in CDB, CDU and/or B2MU analyses, the laboratory
should satisfy the above criteria for a minimum of 2 of the 3
proficiency samples provided in each of the 3 rounds of the CTQ program
over a 6-month period; this procedure should be completed for each
appropriate analyte. Proficiency should be maintained for each analyte
to continue participation. Note that laboratories seeking participation
for CDU or B2MU also should address the performance requirements for
CRTU, which involves providing evidence of accreditation by the CAP and
participation in the CAP surveys (or an equivalent program).
The performance requirement for CDB analysis is defined as an
analytical result within 1 [micro]g/l or 15% of
the consensus mean (whichever is greater). For samples exhibiting a
consensus mean less than 1 [micro]g/l, the performance requirement is
defined as a concentration between the detection limit of the analysis
and a maximum of 2 [micro]g/l. The purpose of redefining the acceptable
interval for low CDB values is to encourage proper reporting of the
actual values obtained during measurement; laboratories, therefore, will
not be penalized (in terms of a narrow range of acceptability) for
reporting measured concentrations less than 1 [micro]g/l.
The performance requirement for CDU analysis is defined as an
analytical result within 1 [micro]g/l urine or 15%
of the consensus mean (whichever is greater). For samples exhibiting a
consensus mean less than 1 [micro]g/l urine, the performance requirement
is defined as a concentration that falls between the detection limit of
the analysis and a maximum of 2 [micro]g/l urine. Performance
requirements for the companion CRTU analysis (defined by the CAP) also
should be met. Note that reporting CDU results, other than for CTQ
proficiency testing should be accompanied with results of CRTU analyses,
and these 2 sets of results should be combined to provide a measure of
CDU in units of [micro]g/g CRTU.
The performance requirement for B2MU is defined as an analytical
result within 15% of the consensus mean. Note that
reporting B2MU results, other than for CTQ proficiency testing should be
accompanied with results of CRTU analysis, these 2 sets of results
should be combined to provide a measure of B2MU in units of [micro]g/g
CRTU.
Once a new laboratory has been approved by the responsible physician
for conducting analyte determinations, the status of this approval
should be reviewed periodically by the responsible physician as per the
criteria presented under Section 3.2.2.
Laboratories which have failed previously to gain approval of the
responsible physician for conducting determinations of 1 or more
analytes due to lack of compliance with the criteria defined above for
existing laboratories (Section 3.2.1), may obtain approval by satisfying
the criteria for newly-formed laboratories defined under this section;
for these laboratories, the second of the above criteria may be
satisfied by submitting a new set of characterization analyses for each
analyte for which determinations are to be made.
Reevaluation of these laboratories is discretionary on the part of
the responsible physician. Reevaluation, which normally takes about 6
months, may be expedited if the laboratory can achieve 100% compliance
with the proficiency test criteria using the 6 samples of each analyte
submitted to the CTQ program during the first 2 rounds of proficiency
testing.
For laboratories seeking reevaluation for CDU or B2MU analysis, the
guidelines for CRTU analyses also should be satisfied, including
accreditation for CRTU analysis by the CAP, and participation in the CAP
survey program (or accreditation/participation in an equivalent
program).
3.2.4 Future Modifications to the Protocol Guidelines
As participating laboratories gain experience with analyses for CDB,
CDU and B2MU, it is anticipated that the performance achievable by the
majority of laboratories should improve until it approaches that
reported by the research groups which developed each method. OSHA,
therefore, may choose to recommend stricter performance guidelines in
the future as the overall performance of participating laboratories
improves.
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3.3 Guidelines for Record Keeping and Reporting
To comply with these guidelines, participating laboratories should
satisfy the above-stated performance and proficiency recommendations, as
well as the following internal QA/QC, record keeping, and reporting
provisions.
If a participating laboratory fails to meet the provisions of these
guidelines, it is recommended that the responsible physician disapprove
further analyses of biological samples by that laboratory until it
demonstrates compliance with these guidelines. On disapproval,
biological samples should be sent to a laboratory that can demonstrate
compliance with these guidelines, at least until the former laboratory
is reevaluated by the responsible physician and found to be in
compliance.
The following record keeping and reporting procedures should be
practiced by participating laboratories.
3.3.1 Internal Quality Assurance/Quality Control Procedures
Laboratories participating in the cadmium monitoring program should
develop and maintain an internal quality assurance/quality control (QA/
QC) program that incorporates procedures for establishing and
maintaining control for each of the analytic procedures (determinations
of CDB, CDU and/or B2MU) for which the laboratory is seeking
participation. For laboratories analyzing CDU and/or B2MU, a QA/QC
program for CRTU also should be established.
Written documentation of QA/QC procedures should be described in a
formal QA/QC plan; this plan should contain the following information:
Sample acceptance and handling procedures (i.e., chain-of-custody);
sample preparation procedures; instrument parameters; calibration
procedures; and, calculations. Documentation of QA/QC procedures should
be sufficient to identify analytical problems, define criteria under
which analysis of compliance samples will be suspended, and describe
procedures for corrective actions.
3.3.1.1 QA/QC procedures for establishing control of CDB and CDU
analyses
The QA/QC program for CDB and CDU should address, at a minimum,
procedures involved in calibration, establishment of control limits,
internal QC analyses and maintaining control, and corrective-action
protocols. Participating laboratory should develop and maintain
procedures to assure that analyses of compliance samples are within
control limits, and that these procedures are documented thoroughly in a
QA/QC plan.
A nonmandatory QA/QC protocol is presented in Attachment 1. This
attachment is illustrative of the procedures that should be addressed in
a proper QA/QC program.
Calibration. Before any analytic runs are conducted, the analytic
instrument should be calibrated. Calibration should be performed at the
beginning of each day on which QC and/or compliance samples are run.
Once calibration is established, QC or compliance samples may be run.
Regardless of the type of samples run, about every fifth sample should
serve as a standard to assure that calibration is being maintained.
Calibration is being maintained if the standard is within 15% of its theoretical value. If a standard is more than
15% of its theoretical value, the run has exceeded
control limits due to calibration error; the entire set of samples then
should be reanalyzed after recalibrating or the results should be
recalculated based on a statistical curve derived from that set of
standards.
It is essential that the value of the highest standard analyzed be
higher than the highest sample analyzed; it may be necessary, therefore,
to run a high standard at the end of the run, which has been selected
based on results obtained over the course of the run (i.e., higher than
any standard analyzed to that point).
Standards should be kept fresh; as samples age, they should be
compared with new standards and replaced if necessary.
Internal Quality Control Analyses. Internal QC samples should be
determined interspersed with analyses of compliance samples. At a
minimum, these samples should be run at a rate of 5% of the compliance
samples or at least one set of QC samples per analysis of compliance
samples, whichever is greater. If only 2 samples are run, they should
contain different levels of cadmium.
Internal QC samples may be obtained as commercially-available
reference materials and/or they may be internally prepared. Internally-
prepared samples should be well characterized and traced, or compared to
a reference material for which a consensus value is available.
Levels of cadmium contained in QC samples should not be known to the
analyst prior to reporting the results of the analysis.
Internal QC results should be plotted or charted in a manner which
describes sample recovery and laboratory control limits.
Internal Control Limits. The laboratory protocol for evaluating
internal QC analyses per control limits should be clearly defined.
Limits may be based on statistical methods (e.g., as 2[sigma] from the
laboratory mean recovery), or on proficiency testing limits (e.g.,1[micro]g or 15% of the mean, whichever is greater).
Statistical limits that exceed 40% should be
reevaluated to determine the source error in the analysis.
When laboratory limits are exceeded, analytic work should terminate
until the source
[[Page 192]]
of error is determined and corrected; compliance samples affected by the
error should be reanalyzed. In addition, the laboratory protocol should
address any unusual trends that develop which may be biasing the
results. Numerous, consecutive results above or below laboratory mean
recoveries, or outside laboratory statistical limits, indicate that
problems may have developed.
Corrective Actions. The QA/QC plan should document in detail
specific actions taken if control limits are exceeded or unusual trends
develop. Corrective actions should be noted on an appropriate form,
accompanied by supporting documentation.
In addition to these actions, laboratories should include whatever
additional actions are necessary to assure that accurate data are
reported to the responsible physicians.
Reference Materials. The following reference materials may be
available:
Cadmium in Blood (CDB)
1. Centre de Toxicologie du Quebec, Le Centre Hospitalier de
l'Universite Laval, 2705 boul. Laurier, Quebec, Que., Canada G1V 4G2.
(Prepared 6 times per year at 1-15 [micro]g Cd/l.)
2. H. Marchandise, Community Bureau of Reference-BCR, Directorate
General XII, Commission of the European Communities, 200, rue de la Loi,
B-1049, Brussels, Belgium. (Prepared as Bl CBM-1 at 5.37 [micro]g Cd/l,
and Bl CBM-2 at 12.38 [micro]g Cd/l.)
3. Kaulson Laboratories Inc., 691 Bloomfield Ave., Caldwell, NJ
07006; tel: (201) 226-9494, FAX (201) 226-3244. (Prepared as
0141 [As, Cd, Hg, Pb] at 2 levels.)
Cadmium in Urine (CDU)
1. Centre de Toxicologie du Quebec, Le Centre Hospitalier de
l'Universite Laval, 2705 boul. Laurier, Quebec, Que., Canada G1V 4G2.
(Prepared 6 times per year.)
2. National Institute of Standards and Technology (NIST), Dept. of
Commerce, Gaithersburg, MD; tel: (301) 975-6776. (Prepared as SRM 2670
freeze-dried urine [metals]; set includes normal and elevated levels of
metals; cadmium is certified for elevated level of 88.0 [micro]g/l in
reconstituted urine.)
3. Kaulson Laboratories Inc., 691 Bloomfield Ave., Caldwell, NJ
07006; tel: (201) 226-9494, FAX (201) 226-3244. (Prepared as
0140 [As, Cd, Hg, Pb] at 2 levels.)
3.3.1.2 QA/QC procedures for establishing control of B2MU
A written, detailed QA/QC plan for B2MU analysis should be
developed. The QA/QC plan should contain a protocol similar to those
protocols developed for the CDB/CDU analyses. Differences in analyses
may warrant some differences in the QA/QC protocol, but procedures to
ensure analytical integrity should be developed and followed.
Examples of performance summaries that can be provided include
measurements of accuracy (i.e., the means of measured values versus
target values for the control samples) and precision (i.e., based on
duplicate analyses). It is recommended that the accuracy and precision
measurements be compared to those reported as achievable by the
Pharmacia Delphia kit (Pharmacia 1990) to determine if and when
unsatisfactory analyses have arisen. If the measurement error of 1 or
more of the control samples is more than 15%, the run exceeds control
limits. Similarly, this decision is warranted when the average CV for
duplicate samples is greater than 5%.
3.3.2 Procedures for Record Keeping
To satisfy reporting requirements for commercial analyses of CDB,
CDU and/or B2MU performed for the medical monitoring program mandated
under the cadmium rule, participating laboratories should maintain the
following documentation for each analyte:
1. For each analytic instrument on which analyte determinations are
made, records relating to the most recent calibration and QC sample
analyses;
2. For these instruments, a tabulated record for each analyte of
those determinations found to be within and outside of control limits
over the past 2 years;
3. Results for the previous 2 years of the QC sample analyses
conducted under the internal QA/QC program (this information should be:
Provided for each analyte for which determinations are made and for each
analytic instrument used for this purpose, sufficient to demonstrate
that internal QA/QC programs are being executed properly, and consistent
with data sent to responsible physicians.
4. Duplicate copies of monitoring results for each analyte sent to
clients during the previous 5 years, as well as associated information;
supporting material such as chain-of-custody forms also should be
retained; and,
5. Proficiency test results and related materials received while
participating in the CTQ interlaboratory program over the past 2 years;
results also should be tabulated to provide a serial record of relative
error (derived per Section 3.3.3 below).
3.3.3 Reporting Procedures
Participating laboratories should maintain these documents: QA/QC
program plans; QA/QC status reports; CTQ proficiency program reports;
and, analytical data reports. The information that should be included in
these reports is summarized in Table 2; a copy of each report should be
sent to the responsible physician.
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Table 2--Reporting Procedures for Laboratories Participating in the
Cadmium Medical Monitoring Program
------------------------------------------------------------------------
Frequency (time
Report frame) Contents
------------------------------------------------------------------------
1 QA/QC Program Plan.......... Once (initially). A detailed
description of the
QA/QC protocol to be
established by the
laboratory to
maintain control of
analyte
determinations.
2 QA/QC Status Report......... Every 2 months... Results of the QC
samples incorporated
into regular runs
for each instrument
(over the period
since the last
report).
3 Proficiency Report.......... Attached to every Results from the last
data report. full year of
proficiency samples
submitted to the CTQ
program and Results
of the 100 most
recent QC samples
incorporated into
regular runs for
each instrument.
4 Analytical Data Report...... For all reports Date the sample was
of data results. received; Date the
sample was analyzed;
Appropriate chain-of-
custody information;
Types of analyses
performed; Results
of the requested
analyses and Copy of
the most current
proficiency report.
------------------------------------------------------------------------
As noted in Section 3.3.1, a QA/QC program plan should be developed
that documents internal QA/QC procedures (defined under Section 3.3.1)
to be implemented by the participating laboratory for each analyte; this
plan should provide a list identifying each instrument used in making
analyte determinations.
A QA/QC status report should be written bimonthly for each analyte.
In this report, the results of the QC program during the reporting
period should be reported for each analyte in the following manner: The
number (N) of QC samples analyzed during the period; a table of the
target levels defined for each sample and the corresponding measured
values; the mean of F/T value (as defined below) for the set of QC
samples run during the period; and, use of X 2[sigma] (as defined below) for the set of QC samples
run during the period as a measure of precision.
As noted in Section 2, an F/T value for a QC sample is the ratio of
the measured concentration of analyte to the established (i.e.,
reference) concentration of analyte for that QC sample. The equation
below describes the derivation of the mean for F/T values, X, (with N
being the total number of samples analyzed):
[GRAPHIC] [TIFF OMITTED] TC28OC91.012
The standard deviation, [sigma], for these measurements is derived using
the following equation (note that 2[sigma] is twice this value):
[GRAPHIC] [TIFF OMITTED] TC28OC91.013
The nonmandatory QA/QC protocol (see Attachment 1) indicates that QC
samples should be divided into several discrete pools, and a separate
estimate of precision for each pools then should be derived. Several
precision estimates should be provided for concentrations which differ
in average value. These precision measures may be used to document
improvements in performance with regard to the combined pool.
Participating laboratories should use the CTQ proficiency program
for each analyte. Results of the this program will be sent by CTQ
directly to physicians designated by the participating laboratories.
Proficiency results from the CTQ program are used to establish the
accuracy of results from each participating laboratory, and should be
provided to responsible physicians for use in trend analysis. A
proficiency report consisting of these proficiency results should
accompany data reports as an attachment.
For each analyte, the proficiency report should include the results
from the 6 previous proficiency rounds in the following format:
1. Number (N) of samples analyzed;
2. Mean of the target levels, (1/N)[Sigma]i, with
Ti being a consensus mean for the sample;
3. Mean of the measurements, (1/N)[Sigma]i, with
Mi being a sample measurement;
4. A measure of error defined by:
(1/N)[Sigma](Ti- Mi)\2\
Analytical data reports should be submitted to responsible
physicians directly. For each sample, report the following information:
The date the sample was received; the date the sample was analyzed;
appropriate chain-of-custody information; the type(s) of analyses
performed; and, the results of the analyses. This information should be
reported on a form similar to the form provided an appropriate form. The
most recent proficiency program report should accompany the analytical
data reports (as an attachment).
Confidence intervals for the analytical results should be reported
as X2[sigma], with X being the measured value and
2[sigma] the standard deviation calculated as described above.
[[Page 194]]
For CDU or B2MU results, which are combined with CRTU measurements
for proper reporting, the 95% confidence limits are derived from the
limits for CDU or B2MU, (p), and the limits for CRTU, (q), as follows:
[GRAPHIC] [TIFF OMITTED] TC28OC91.014
For these calculations, X p is the measurement and
confidence limits for CDU or B2MU, and Y q is the
measurement and confidence limit for CRTU.
Participating laboratories should notify responsible physicians as
soon as they receive information indicating a change in their
accreditation status with the CTQ or the CAP. These physicians should
not be expected to wait until formal notice of a status change has been
received from the CTQ or the CAP.
3.4 Instructions to Physicians
Physicians responsible for the medical monitoring of cadmium-exposed
workers must collect the biological samples from workers; they then
should select laboratories to perform the required analyses, and should
interpret the analytic results.
3.4.1 Sample Collection and Holding Procedures
Blood Samples. The following procedures are recommended for the
collection, shipment and storage of blood samples for CDB analysis to
reduce analytical variablility; these recommendations were obtained
primarily through personal communications with J.P. Weber of the CTQ
(1991), and from reports by the Centers for Disease Control (CDC, 1986)
and Stoeppler and Brandt (1980).
To the extent possible, blood samples should be collected from
workers at the same time of day. Workers should shower or thoroughly
wash their hands and arms before blood samples are drawn. The following
materials are needed for blood sample collection: Alcohol wipes; sterile
gauze sponges; band-aids; 20-gauge, 1.5-in. stainless steel needles
(sterile); preprinted labels; tourniquets; vacutainer holders; 3-ml
``metal free'' vacutainer tubes (i.e., dark-blue caps), with EDTA as an
anti-coagulant; and, styrofoam vacutainer shipping containers.
Whole blood samples are taken by venipuncture. Each blue-capped tube
should be labeled or coded for the worker and company before the sample
is drawn. (Blue-capped tubes are recommended instead of red-capped tubes
because the latter may consist of red coloring pigment containing
cadmium, which could contaminate the samples.) Immediately after
sampling, the vacutainer tubes must be thoroughly mixed by inverting the
tubes at least 10 times manually or mechanically using a Vortex device
(for 15 sec). Samples should be refrigerated immediately or stored on
ice until they can be packed for shipment to the participating
laboratory for analysis.
The CDC recommends that blood samples be shipped with a ``cool pak''
to keep the samples cold during shipment. However, the CTQ routinely
ships and receives blood samples for cadmium analysis that have not been
kept cool during shipment. The CTQ has found no deterioration of cadmium
in biological fluids that were shipped via parcel post without a cooling
agent, even though these deliveries often take 2 weeks to reach their
destination.
Urine Samples. The following are recommended procedures for the
collection, shipment and storage of urine for CDU and B2MU analyses, and
were obtained primarily through personal communications with J.P. Weber
of the CTQ (1991), and from reports by the CDC (1986) and Stoeppler and
Brandt (1980).
Single ``spot'' samples are recommended. As B2M can degrade in the
bladder, workers should first empty their bladder and then drink a large
glass of water at the start of the visit. Urine samples then should be
collected within 1 hour. Separate samples should be collected for CDU
and B2MU using the following materials: Sterile urine collection cups
(250 ml); small sealable plastic bags; preprinted labels; 15-ml
polypropylene or polyethylene screw-cap tubes; lab gloves (``metal
free''); and, preservatives (as indicated).
The sealed collection cup should be kept in the plastic bag until
collection time. The workers should wash their hands with soap and water
before receiving the collection cup. The collection cup should not be
opened until just before voiding and the cup should be sealed
immediately after filling. It is important that the inside of the
container and cap are not touched by, or come into contact with, the
body, clothing or other surfaces.
For CDU analyzes, the cup is swirled gently to resuspend any solids,
and the 15-ml tube is filled with 10-12 ml urine. The CDC recommends the
addition of 100 [micro]l concentrated HNO3 as a preservative
before sealing the tube and then freezing the sample. The CTQ recommends
minimal handling and does not acidify their interlaboratory urine
reference materials prior to shipment, nor do they freeze the sample for
shipment. At the CTQ, if the urine sample has much sediment, the sample
is acidified in the lab to free any cadmium in the precipitate.
For B2M, the urine sample should be collected directly into a
polyethylene bottle previously washed with dilute nitric acid. The pH of
the urine should be measured and adjusted to 8.0 with 0.1 N NaOH
immediately
[[Page 195]]
following collection. Samples should be frozen and stored at -20 [deg]C
until testing is performed. The B2M in the samples should be stable for
2 days when stored at 2-8 [deg]C, and for at least 2 months at -20
[deg]C. Repeated freezing and thawing should be avoided to prevent
denaturing the B2M (Pharmacia 1990).
3.4.2 Recommendations for Evaluating Laboratories
Using standard error data and the results of proficiency testing
obtained from CTQ, responsible physicians can make an informed choice of
which laboratory to select to analyze biological samples. In general,
laboratories with small standard errors and little disparity between
target and measured values tend to make precise and accurate sample
determinations. Estimates of precision provided to the physicians with
each set of monitoring results can be compared to previously-reported
proficiency and precision estimates. The latest precision estimates
should be at least as small as the standard error reported previously by
the laboratory. Moreover, there should be no indication that precision
is deteriorating (i.e., increasing values for the precision estimates).
If precision is deteriorating, physicians may decide to use another
laboratory for these analyses. QA/QC information provided by the
participating laboratories to physicians can, therefore, assist
physicians in evaluating laboratory performance.
3.4.3 Use and Interpretation of Results
When the responsible physician has received the CDB, CDU and/or B2MU
results, these results must be compared to the action levels discussed
in the final rule for cadmium. The comparison of the sample results to
action levels is straightforward. The measured value reported from the
laboratory can be compared directly to the action levels; if the
reported value exceeds an action level, the required actions must be
initiated.
4.0 Background
Cadmium is a naturally-occurring environmental contaminant to which
humans are continually exposed in food, water, and air. The average
daily intake of cadmium by the U.S. population is estimated to be 10-20
[micro]g/day. Most of this intake is via ingestion, for which absorption
is estimated at 4-7% (Kowal et al. 1979). An additional nonoccupational
source of cadmium is smoking tobacco; smoking a pack of cigarettes a day
adds an additional 2-4 [micro]g cadmium to the daily intake, assuming
absorption via inhalation of 25-35% (Nordberg and Nordberg 1988; Friberg
and Elinder 1988; Travis and Haddock 1980).
Exposure to cadmium fumes and dusts in an occupational setting where
air concentrations are 20-50 [micro]g/m\3\ results in an additional
daily intake of several hundred micrograms (Friberg and Elinder 1988, p.
563). In such a setting, occupational exposure to cadmium occurs
primarily via inhalation, although additional exposure may occur through
the ingestion of material via contaminated hands if workers eat or smoke
without first washing. Some of the particles that are inhaled initially
may be ingested when the material is deposited in the upper respiratory
tract, where it may be cleared by mucociliary transport and subsequently
swallowed.
Cadmium introduced into the body through inhalation or ingestion is
transported by the albumin fraction of the blood plasma to the liver,
where it accumulates and is stored principally as a bound form complexed
with the protein metallothionein. Metallothionein-bound cadmium is the
main form of cadmium subsequently transported to the kidney; it is these
2 organs, the liver and kidney, in which the majority of the cadmium
body burden accumulates. As much as one half of the total body burden of
cadmium may be found in the kidneys (Nordberg and Nordberg 1988).
Once cadmium has entered the body, elimination is slow; about 0.02%
of the body burden is excreted per day via urinary/fecal elimination.
The whole-body half-life of cadmium is 10-35 years, decreasing slightly
with increasing age (Travis and Haddock 1980).
The continual accumulation of cadmium is the basis for its chronic
noncarcinogenic toxicity. This accumulation makes the kidney the target
organ in which cadmium toxicity usually is first observed (Piscator
1964). Renal damage may occur when cadmium levels in the kidney cortex
approach 200 [micro]g/g wet tissue-weight (Travis and Haddock 1980).
The kinetics and internal distribution of cadmium in the body are
complex, and depend on whether occupational exposure to cadmium is
ongoing or has terminated. In general, cadmium in blood is related
principally to recent cadmium exposure, while cadmium in urine reflects
cumulative exposure (i.e., total body burden) (Lauwerys et al. 1976;
Friberg and Elinder 1988).
4.1 Health Effects
Studies of workers in a variety of industries indicate that chronic
exposure to cadmium may be linked to several adverse health effects
including kidney dysfunction, reduced pulmonary function, chronic lung
disease and cancer (Federal Register 1990). The primary sites for
cadmium-associated cancer appear to be the lung and the prostate.
Cancer. Evidence for an association between cancer and cadmium
exposure comes from both epidemiological studies and animal experiments.
Pott (1965) found a statistically significant elevation in the incidence
[[Page 196]]
of prostate cancer among a cohort of cadmium workers. Other epidemiology
studies also report an elevated incidence of prostate cancer; however,
the increases observed in these other studies were not statistically
significant (Meridian Research, Inc. 1989).
One study (Thun et al. 1985) contains sufficiently quantitative
estimates of cadmium exposure to allow evaluation of dose-response
relationships between cadmium exposure and lung cancer. A statistically
significant excess of lung cancer attributed to cadmium exposure was
found in this study, even after accounting for confounding variables
such as coexposure to arsenic and smoking habits (Meridian Research,
Inc. 1989).
Evidence for quantifying a link between lung cancer and cadmium
exposure comes from a single study (Takenaka et al. 1983). In this
study, dose-response relationships developed from animal data were
extrapolated to humans using a variety of models. OSHA chose the
multistage risk model for estimating the risk of cancer for humans using
these animal data. Animal injection studies also suggest an association
between cadmium exposure and cancer, particularly observations of an
increased incidence of tumors at sites remote from the point of
injection. The International Agency for Research on Cancer (IARC)
(Supplement 7, 1987) indicates that this, and related, evidence is
sufficient to classify cadmium as an animal carcinogen. However, the
results of these injection studies cannot be used to quantify risks
attendant to human occupational exposures due to differences in routes
of exposure (Meridian Research, Inc. 1989).
Based on the above-cited studies, the U.S. Environmental Protection
Agency (EPA) classifies cadmium as ``B1,'' a probable human carcinogen
(USEPA 1985). IARC in 1987 recommended that cadmium be listed as a
probable human carcinogen.
Kidney Dysfunction. The most prevalent nonmalignant effect observed
among workers chronically exposed to cadmium is kidney dysfunction.
Initially, such dysfunction is manifested by proteinuria (Meridian
Research, Inc. 1989; Roth Associates, Inc. 1989). Proteinuria associated
with cadmium exposure is most commonly characterized by excretion of
low-molecular weight proteins (15,000-40,000 MW), accompanied by loss of
electrolytes, uric acid, calcium, amino acids, and phosphate. Proteins
commonly excreted include [beta]-2-microglobulin (B2M), retinol-binding
protein (RBP), immunoglobulin light chains, and lysozyme. Excretion of
low molecular weight proteins is characteristic of damage to the
proximal tubules of the kidney (Iwao et al. 1980).
Exposure to cadmium also may lead to urinary excretion of high-
molecular weight proteins such as albumin, immunoglobulin G, and
glycoproteins (Meridian Research, Inc. 1989; Roth Associates, Inc.
1989). Excretion of high-molecular weight proteins is indicative of
damage to the glomeruli of the kidney. Bernard et al. (1979) suggest
that cadmium-associated damage to the glomeruli and damage to the
proximal tubules of the kidney develop independently of each other, but
may occur in the same individual.
Several studies indicate that the onset of low-molecular weight
proteinuria is a sign of irreversible kidney damage (Friberg et al.
1974; Roels et al. 1982; Piscator 1984; Elinder et al. 1985; Smith et
al. 1986). For many workers, once sufficiently elevated levels of B2M
are observed in association with cadmium exposure, such levels do not
appear to return to normal even when cadmium exposure is eliminated by
removal of the worker from the cadmium-contaminated work environment
(Friberg, exhibit 29, 1990).
Some studies indicate that cadmium-induced proteinuria may be
progressive; levels of B2MU increase even after cadmium exposure has
ceased (Elinder et al. 1985). Other researchers have reached similar
conclusions (Frieburg testimony, OSHA docket exhibit 29, Elinder
testimony, OSHA docket exhibit 55, and OSHA docket exhibits 8-86B). Such
observations are not universal, however (Smith et al. 1986; Tsuchiya
1976). Studies in which proteinuria has not been observed, however, may
have initiated the reassessment too early (Meridian Research, Inc.1989;
Roth Associates, Inc. 1989; Roels 1989).
A quantitative assessment of the risks of developing kidney
dysfunction as a result of cadmium exposure was performed using the data
from Ellis et al. (1984) and Falck et al. (1983). Meridian Research,
Inc. (1989) and Roth Associates, Inc. (1989) employed several
mathematical models to evaluate the data from the 2 studies, and the
results indicate that cumulative cadmium exposure levels between 5 and
100 [micro]g-years/m\3\ correspond with a one-in-a-thousand probability
of developing kidney dysfunction.
When cadmium exposure continues past the onset of early kidney
damage (manifested as proteinuria), chronic nephrotoxicity may occur
(Meridian Research, Inc. 1989; Roth Associates, Inc. 1989). Uremia,
which is the loss of the glomerulus' ability to adequately filter blood,
may result. This condition leads to severe disturbance of electrolyte
concentrations, which may result in various clinical complications
including atherosclerosis, hypertension, pericarditis, anemia,
hemorrhagic tendencies, deficient cellular immunity, bone changes, and
other problems. Progression of the disease may require dialysis or a
kidney transplant.
Studies in which animals are chronically exposed to cadmium confirm
the renal effects observed in humans (Friberg et al. 1986). Animal
studies also confirm cadmium-related problems with calcium metabolism
and associated skeletal effects, which also
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have been observed among humans. Other effects commonly reported in
chronic animal studies include anemia, changes in liver morphology,
immunosuppression and hypertension. Some of these effects may be
associated with cofactors; hypertension, for example, appears to be
associated with diet, as well as with cadmium exposure. Animals injected
with cadmium also have shown testicular necrosis.
4.2 Objectives for Medical Monitoring
In keeping with the observation that renal disease tends to be the
earliest clinical manifestation of cadmium toxicity, the final cadmium
standard mandates that eligible workers must be medically monitored to
prevent this condition (as well as cadmimum-induced cancer). The
objectives of medical-monitoring, therefore, are to: Identify workers at
significant risk of adverse health effects from excess, chronic exposure
to cadmium; prevent future cases of cadmium-induced disease; detect and
minimize existing cadmium-induced disease; and, identify workers most in
need of medical intervention.
The overall goal of the medical monitoring program is to protect
workers who may be exposed continuously to cadmium over a 45-year
occupational lifespan. Consistent with this goal, the medical monitoring
program should assure that:
1. Current exposure levels remain sufficiently low to prevent the
accumulation of cadmium body burdens sufficient to cause disease in the
future by monitoring CDB as an indicator of recent cadmium exposure;
2. Cumulative body burdens, especially among workers with undefined
historical exposures, remain below levels potentially capable of leading
to damage and disease by assessing CDU as an indicator of cumulative
exposure to cadmium; and,
3. Health effects are not occurring among exposed workers by
determining B2MU as an early indicator of the onset of cadmium-induced
kidney disease.
4.3 Indicators of Cadmium Exposure and Disease
Cadmium is present in whole blood bound to albumin, in erythrocytes,
and as a metallothionein-cadmium complex. The metallothionein-cadmium
complex that represents the primary transport mechanism for cadmium
delivery to the kidney. CDB concentrations in the general, nonexposed
population average 1 [micro]g Cd/l whole blood, with smokers exhibiting
higher levels (see Section 5.1.6). Data presented in Section 5.1.6 shows
that 95% of the general population not occupationally exposed to cadmium
have CDB levels less than 5 [micro]g Cd/l.
If total body burdens of cadmium remain low, CDB concentrations
indicate recent exposure (i.e., daily intake). This conclusion is based
on data showing that cigarette smokers exhibit CDB concentrations of 2-7
[micro]g/l depending on the number of cigarettes smoked per day
(Nordberg and Nordberg 1988), while CDB levels for those who quit
smoking return to general population values (approximately 1 [micro]g/l)
within several weeks (Lauwerys et al. 1976). Based on these
observations, Lauwerys et al. (1976) concluded that CDB has a biological
half-life of a few weeks to less than 3 months. As indicated in Section
3.1.6, the upper 95th percentile for CDB levels observed among those who
are not occupationally exposed to cadmium is 5 [micro]g/l, which
suggests that the absolute upper limit to the range reported for smokers
by Nordberg and Nordberg may have been affected by an extreme value
(i.e., beyond 2[sigma] above the mean).
Among occupationally-exposed workers, the occupational history of
exposure to cadmium must be evaluated to interpret CDB levels. New
workers, or workers with low exposures to cadmium, exhibit CDB levels
that are representative of recent exposures, similar to the general
population. However, for workers with a history of chronic exposure to
cadmium, who have accumulated significant stores of cadmium in the
kidneys/liver, part of the CDB concentrations appear to indicate body
burden. If such workers are removed from cadmium exposure, their CDB
levels remain elevated, possibly for years, reflecting prior long-term
accumulation of cadmium in body tissues. This condition tends to occur,
however, only beyond some threshold exposure value, and possibly
indicates the capacity of body tissues to accumulate cadmium which
cannot be excreted readily (Friberg and Elinder 1988; Nordberg and
Nordberg 1988).
CDU is widely used as an indicator of cadmium body burdens (Nordberg
and Nordberg 1988). CDU is the major route of elimination and, when CDU
is measured, it is commonly expressed either as [micro]g Cd/l urine
(unadjusted), [micro]g Cd/l urine (adjusted for specific gravity), or
[micro]g Cd/g CRTU (see Section 5.2.1). The metabolic model for CDU is
less complicated than CDB, since CDU is dependentin large part on the
body (i.e., kidney) burden of cadmium. However, a small proportion of
CDU still be attributed to recent cadmium exposure, particularly if
exposure to high airborne concentrations of cadmium occurred. Note that
CDU is subject to larger interindividual and day-to-day variations than
CDB, so repeated measurements are recommended for CDU evaluations.
CDU is bound principally to metallothionein, regardless of whether
the cadmium originates from metallothionein in plasma or from the
cadmium pool accumulated in the renal tubules. Therefore, measurement of
metallothionein in urine may provide information similar to CDU, while
avoiding the contamination problems that
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may occur during collection and handling urine for cadmium analysis
(Nordberg and Nordberg 1988). However, a commercial method for the
determination of metallothionein at the sensitivity levels required
under the final cadmium rule is not currently available; therefore,
analysis of CDU is recommended.
Among the general population not occupationally exposed to cadmium,
CDU levels average less than 1 [micro]g/l (see Section 5.2.7).
Normalized for creatinine (CRTU), the average CDU concentration of the
general population is less than 1 [micro]g/g CRTU. As cadmium
accumulates over the lifespan, CDU increases with age. Also, cigarette
smokers may eventually accumulate twice the cadmium body burden of
nonsmokers, CDU is slightly higher in smokers than in nonsmokers, even
several years after smoking cessation (Nordberg and Nordberg 1988).
Despite variations due to age and smoking habits, 95% of those not
occupationally exposed to cadmium exhibit levels of CDU less than 3
[micro]g/g CRTU (based on the data presented in Section 5.2.7).
About 0.02% of the cadmium body burden is excreted daily in urine.
When the critical cadmium concentration (about 200 ppm) in the kidney is
reached, or if there is sufficient cadmium-induced kidney dysfunction,
dramatic increases in CDU are observed (Nordberg and Nordberg 1988).
Above 200 ppm, therefore, CDU concentrations cease to be an indicator of
cadmium body burden, and are instead an index of kidney failure.
Proteinuria is an index of kidney dysfunction, and is defined by
OSHA to be a material impairment. Several small proteins may be
monitored as markers for proteinuria. Below levels indicative of
proteinuria, these small proteins may be early indicators of increased
risk of cadmium-induced renal tubular disease. Analytes useful for
monitoring cadmium-induced renal tubular damage include:
1. [beta]-2-Microglobulin (B2M), currently the most widely used
assay for detecting kidney dysfunction, is the best characterized
analyte available (Iwao et al. 1980; Chia et al. 1989);
2. Retinol Binding Protein (RBP) is more stable than B2M in acidic
urine (i.e., B2M breakdown occurs if urinary pH is less than 5.5; such
breakdown may result in false [i.e., low] B2M values [Bernard and
Lauwerys, 1990]);
3. N-Acetyl-B-Glucosaminidase (NAG) is the analyte of an assay that
is simple, inexpensive, reliable, and correlates with cadmium levels
under 10 [micro]g/g CRTU, but the assay is less sensitive than RBP or
B2M (Kawada et al. 1989);
4. Metallothionein (MT) correlates with cadmium and B2M levels, and
may be a better predictor of cadmium exposure than CDU and B2M (Kawada
et al. 1989);
5. Tamm-Horsfall Glycoprotein (THG) increases slightly with elevated
cadmium levels, but this elevation is small compared to increases in
urinary albumin, RBP, or B2M (Bernard and Lauwerys 1990);
6. Albumin (ALB), determined by the biuret method, is not
sufficiently sensitive to serve as an early indicator of the onset of
renal disease (Piscator 1962);
7. Albumin (ALB), determined by the Amido Black method, is sensitive
and reproducible, but involves a time-consuming procedure (Piscator
1962);
8. Glycosaminoglycan (GAG) increases among cadmium workers, but the
significance of this effect is unknown because no relationship has been
found between elevated GAG and other indices of tubular damage (Bernard
and Lauwerys 1990);
9. Trehalase seems to increase earlier than B2M during cadmium
exposure, but the procedure for analysis is complicated and unreliable
(Iwata et al. 1988); and,
10. Kallikrein is observed at lower concentrations among cadmium-
exposed workers than among normal controls (Roels et al. 1990).
Of the above analytes, B2M appears to be the most widely used and
best characterized analyte to evaluate the presence/absence, as well as
the extent of, cadmium-induced renal tubular damage (Kawada, Koyama, and
Suzuki 1989; Shaikh and Smith 1984; Nogawa 1984). However, it is
important that samples be collected and handled so as to minimize B2M
degradation under acidic urine conditions.
The threshold value of B2MU commonly used to indicate the presence
of kidney damage 300 [micro]g/g CRTU (Kjellstrom et al. 1977a; Buchet et
al. 1980; and Kowal and Zirkes 1983). This value represents the upper
95th or 97.5th percentile level of urinary excretion observed among
those without tubular dysfunction (Elinder, exbt L-140-45, OSHA docket
H057A). In agreement with these conclusions, the data presented in
Section 5.3.7 of this protocol generally indicate that the level of 300
[micro]g/g CRTU appears to define the boundary for kidney dysfunction.
It is not clear, however, that this level represents the upper 95th
percentile of values observed among those who fail to demonstrate
proteinuria effects.
Although elevated B2MU levels appear to be a fairly specific
indicator of disease associated with cadmium exposure, other conditions
that may lead to elevated B2MU levels include high fevers from
influenza, extensive physical exercise, renal disease unrelated to
cadmium exposure, lymphomas, and AIDS (Iwao et al. 1980; Schardun and
van Epps 1987). Elevated B2M levels observed in association with high
fevers from influenza or from extensive physical exercise are transient,
and will return to normal levels once
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the fever has abated or metabolic rates return to baseline values
following exercise. The other conditions linked to elevated B2M levels
can be diagnosed as part of a properly-designed medical examination.
Consequently, monitoring B2M, when accompanied by regular medical
examinations and CDB and CDU determinations (as indicators of present
and past cadmium exposure), may serve as a specific, early indicator of
cadmium-induced kidney damage.
4.4 Criteria for Medical Monitoring of Cadmium Workers
Medical monitoring mandated by the final cadmium rule includes a
combination of regular medical examinations and periodic monitoring of 3
analytes: CDB, CDU and B2MU. As indicated above, CDB is monitored as an
indicator of current cadmium exposure, while CDU serves as an indicator
of the cadmium body burden; B2MU is assessed as an early marker of
irreversible kidney damage and disease.
The final cadmium rule defines a series of action levels that have
been developed for each of the 3 analytes to be monitored. These action
levels serve to guide the responsible physician through a decision-
making process. For each action level that is exceeded, a specific
response is mandated. The sequence of action levels, and the attendant
actions, are described in detail in the final cadmium rule.
Other criteria used in the medical decision-making process relate to
tests performed during the medical examination (including a
determination of the ability of a worker to wear a respirator). These
criteria, however, are not affected by the results of the analyte
determinations addressed in the above paragraphs and, consequently, will
not be considered further in these guidelines.
4.5 Defining to Quality and Proficiency of the Analyte Determinations
As noted above in Sections 2 and 3, the quality of a measurement
should be defined along with its value to properly interpret the
results. Generally, it is necessary to know the accuracy and the
precision of a measurement before it can be properly evaluated. The
precision of the data from a specific laboratory indicates the extent to
which the repeated measurements of the same sample vary within that
laboratory. The accuracy of the data provides an indication of the
extent to which these results deviate from average results determined
from many laboratories performing the same measurement (i.e., in the
absence of an independent determination of the true value of a
measurement). Note that terms are defined operationally relative to the
manner in which they will be used in this protocol. Formal definitions
for the terms in italics used in this section can be found in the list
of definitions (Section 2).
Another data quality criterion required to properly evaluate
measurement results is the limit of detection of that measurement. For
measurements to be useful, the range of the measurement which is of
interest for biological monitoring purposes must lie entirely above the
limit of detection defined for that measurement.
The overall quality of a laboratory's results is termed the
performance of that laboratory. The degree to which a laboratory
satisfies a minimum performance level is referred to as the proficiency
of the laboratory. A successful medical monitoring program, therefore,
should include procedures developed for monitoring and recording
laboratory performance; these procedures can be used to identify the
most proficient laboratories.
5.0 Overview of Medical Monitoring Tests for CDB, CDU, B2MU and CRTU
To evaluate whether available methods for assessing CDB, CDU, B2MU
and CRTU are adequate for determining the parameters defined by the
proposed action levels, it is necessary to review procedures available
for sample collection, preparation and analysis. A variety of techniques
for these purposes have been used historically for the determination of
cadmium in biological matrices (including CDB and CDU), and for the
determination of specific proteins in biological matrices (including
B2MU). However, only the most recent techniques are capable of
satisfying the required accuracy, precision and sensitivity (i.e., limit
of detection) for monitoring at the levels mandated in the final cadmium
rule, while still facilitating automated analysis and rapid processing.
5.1 Measuring Cadmium in Blood (CDB)
Analysis of biological samples for cadmium requires strict
analytical discipline regarding collection and handling of samples. In
addition to occupational settings, where cadmium contamination would be
apparent, cadmium is a ubiquitous environmental contaminant, and much
care should be exercised to ensure that samples are not contaminated
during collection, preparation or analysis. Many common chemical
reagents are contaminated with cadmium at concentrations that will
interfere with cadmium analysis; because of the widespread use of
cadmium compounds as colored pigments in plastics and coatings, the
analyst should continually monitor each manufacturer's chemical reagents
and collection containers to prevent contamination of samples.
Guarding against cadmium contamination of biological samples is
particularly important when analyzing blood samples because cadmium
concentrations in blood samples
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from nonexposed populations are generally less than 2 [micro]g/l (2 ng/
ml), while occupationally-exposed workers can be at medical risk to
cadmium toxicity if blood concentrations exceed 5 [micro]g/l (ACGIH 1991
and 1992). This narrow margin between exposed and unexposed samples
requires that exceptional care be used in performing analytic
determinations for biological monitoring for occupational cadmium
exposure.
Methods for quantifying cadmium in blood have improved over the last
40 years primarily because of improvements in analytical
instrumentation. Also, due to improvements in analytical techniques,
there is less need to perform extensive multi-step sample preparations
prior to analysis. Complex sample preparation was previously required to
enhance method sensitivity (for cadmium), and to reduce interference by
other metals or components of the sample.
5.1.1 Analytical Techniques Used To Monitor Cadmium in Biological
Matrices
Table 3--Comparison of Analytical Procedures/Instrumentation for Determination of Cadmium in Biological Samples
----------------------------------------------------------------------------------------------------------------
Limit of
Analytical procedure detection [ng/ Specified biological Reference Comments
(g or ml)] matrix
----------------------------------------------------------------------------------------------------------------
Flame Atomic Absorption =1. Any matrix............. Perkin-Elmer (1982).... Not sensitive enough
Spectroscopy (FAAS). 0 for biomonitoring
without extensive
sample digestion,
metal chelation and
organic solvent
extraction.
Graphite Furnace Atomic 0.04 Urine.................. Pruszkowska et al. Methods of choice for
Absorption (1983). routine cadmium
Spectroscopy (GFAAS). analysis.
=0. Blood.................. Stoeppler and Brandt
20 (1980).
Inductively-Coupled 2.0 Any matrix............. NIOSH (1984A).......... Requires extensive
Argon-Plasma Atomic sample preparation
Emission Spectroscopy and concentration of
(ICAP AES). metal with chelating
resin. Advantage is
simultaneous
analyses for as many
as 10 metals from 1
sample.
Neutron Activation 1.5 In vivo (liver)........ Ellis et al. (1983).... Only available in
Gamma Spectroscopy vivo method for
(NA). direct determination
of cadmium body
tissue burdens;
expensive; absolute
determination of
cadmium in reference
materials.
Isotope Dilution Mass <1.0 Any matrix............. Michiels and DeBievre Suitable for absolute
Spectroscopy (IDMS). (1986). determination of
cadmium in reference
materials;
expensive.
Differential Pulse <1.0 Any matrix............. Stoeppler and Brandt Suitable for absolute
Anodic Stripping (1980). determination of
Voltammetry (DPASV). cadmium in reference
materials; efficient
method to check
accuracy of
analytical method.
----------------------------------------------------------------------------------------------------------------
A number of analytical techniques have been used for determining
cadmium concentrations in biological materials. A summary of the
characteristics of the most widely employed techniques is presented in
Table 3. The technique most suitable for medical monitoring for cadmium
is atomic absorption spectroscopy (AAS).
To obtain a measurement using AAS, a light source (i.e., hollow
cathode or lectrode-free discharge lamp) containing the element of
interest as the cathode, is energized and the lamp emits a spectrum that
is unique for that element. This light source is focused through a
sample cell, and a selected wavelength is monitored by a monochrometer
and photodetector cell. Any ground state atoms in the sample that match
those of the lamp element and are in the path of the emitted light may
absorb some of the light and decrease the amount of light that reaches
the photodetector cell. The amount of light absorbed at each
characteristic wavelength is proportional to the number of ground state
atoms of the corresponding element that are in the pathway of the light
between the source and detector.
To determine the amount of a specific metallic element in a sample
using AAS, the sample is dissolved in a solvent and aspirated into a
high-temperature flame as an aerosol. At high temperatures, the solvent
is rapidly evaporated or decomposed and the solute is initially
solidified; the majority of the sample elements then are transformed
into an atomic vapor. Next, a light beam is focused above the flame and
the amount of metal in the sample can be determined by measuring the
degree of absorbance of the atoms of the target element released by the
flame at a characteristic wavelength.
A more refined atomic absorption technique, flameless AAS,
substitutes an electrothermal, graphite furnace for the
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flame. An aliquot (10-100 [micro]l) of the sample is pipetted into the
cold furnace, which is then heated rapidly to generate an atomic vapor
of the element.
AAS is a sensitive and specific method for the elemental analysis of
metals; its main drawback is nonspecific background absorbtion and
scattering of the light beam by particles of the sample as it decomposes
at high temperatures; nonspecific absorbance reduces the sensitivity of
the analytical method. The problem of nonspecific absorbance and
scattering can be reduced by extensive sample pretreatment, such as
ashing and/or acid digestion of the sample to reduce its organic
content.
Current AAS instruments employ background correction devices to
adjust electronically for background absorbtion and scattering. A common
method to correct for background effects is to use a deuterium arc lamp
as a second light source. A continuum light source, such as the
deuterium lamp, emits a broad spectrum of wavelengths instead of
specific wavelengths characteristic of a particular element, as with the
hollow cathode tube. With this system, light from the primary source and
the continuum source are passed alternately through the sample cell. The
target element effectively absorbs light only from the primary source
(which is much brighter than the continuum source at the characteristic
wavelengths), while the background matrix absorbs and scatters light
from both sources equally. Therefore, when the ratio of the two beams is
measured electronically, the effect of nonspecific background absorption
and scattering is eliminated. A less common, but more sophisticated,
backgrond correction system is based on the Zeeman effect, which uses a
magnetically-activated light polarizer to compensate electronically for
nonspecific absorbtion and scattering.
Atomic emission spectroscopy with inductively-coupled argon plasma
(AES-ICAP) is widely used to analyze for metals. With this instrument,
the sample is aspirated into an extremely hot argon plasma flame, which
excites the metal atoms; emission spectra specific for the sample
element then are generated. The quanta of emitted light passing through
a monochrometer are amplified by photomultiplier tubes and measured by a
photodetector to determine the amount of metal in the sample. An
advantage of AES-ICAP over AAS is that multi-elemental analyses of a
sample can be performed by simultaneously measuring specific elemental
emission energies. However, AES-ICAP lacks the sensitivity of AAS,
exhibiting a limit of detection which is higher than the limit of
detection for graphite-furnace AAS (Table 3).
Neutron activation (NA) analysis and isotope dilution mass
spectrometry (IDMS) are 2 additional, but highly specialized, methods
that have been used for cadmium determinations. These methods are
expensive because they require elaborate and sophisticated
instrumentation.
NA analysis has the distinct advantage over other analytical methods
of being able to determine cadmium body burdens in specific organs
(e.g., liver, kidney) in vivo (Ellis et al. 1983). Neutron bombardment
of the target transforms cadmium-113 to cadmium-114, which promptly
decays (<10-14 sec) to its ground state, emitting gamma rays
that are measured using large gamma detectors; appropriate shielding and
instrumentation are required when using this method.
IDMS analysis, a definitive but laborious method, is based on the
change in the ratio of 2 isotopes of cadmium (cadmium 111 and 112) that
occurs when a known amount of the element (with an artificially altered
ratio of the same isotopes [i.e., a cadmium 111 ``spike''] is added to a
weighed aliquot of the sample (Michiels and De Bievre 1986).
5.1.2 Methods Developed for CDB Determinations
A variety of methods have been used for preparing and analyzing CDB
samples; most of these methods rely on one of the analytical techniques
described above. Among the earliest reports, Princi (1947) and Smith et
al. (1955) employed a colorimetric procedure to analyze for CDB and CDU.
Samples were dried and digested through several cycles with concentrated
mineral acids (HNO3 and H2 SO4) and
hydrogen peroxide (H2 O2). The digest was
neutralized, and the cadmium was complexed with diphenylthiocarbazone
and extracted with chloroform. The dithizone-cadmium complex then was
quantified using a spectrometer.
Colorimetric procedures for cadmium analyses were replaced by
methods based on atomic absorption spectroscopy (AAS) in the early
1960s, but many of the complex sample preparation procedures were
retained. Kjellstrom (1979) reports that in Japanese, American and
Swedish laboratories during the early 1970s, blood samples were wet
ashed with mineral acids or ashed at high temperature and wetted with
nitric acid. The cadmium in the digest was complexed with metal
chelators including diethyl dithiocarbamate (DDTC), ammonium pyrrolidine
dithiocarbamate (APDC) or diphenylthiocarbazone (dithizone) in ammonia-
citrate buffer and extracted with methyl isobutyl ketone (MIBK). The
resulting solution then was analyzed by flame AAS or graphite-furnace
AAS forcadmium determinations using deuterium-lamp background
correction.
In the late 1970s, researchers began developing simpler preparation
procedures. Roels et al. (1978) and Roberts and Clark (1986) developed
simplified digestion procedures. Using the Roberts and Clark method, a
0.5
[[Page 202]]
ml aliquot of blood is collected and transferred to a digestion tube
containing 1 ml concentrated HNO3. The blood is then digested
at 110 [deg]C for 4 hours. The sample is reduced in volume by continued
heating, and 0.5 ml 30% H2 O2 is added as the
sample dries. The residue is dissolved in 5 ml dilute (1%)
HNO3, and 20 [micro]l of sample is then analyzed by graphite-
furnace AAS with deuterium-background correction.
The current trend in the preparation of blood samples is to dilute
the sample and add matrix modifiers to reduce background interference,
rather than digesting the sample to reduce organic content. The method
of Stoeppler and Brandt (1980), and the abbreviated procedure published
in the American Public Health Association's (APHA) Methods for
Biological Monitoring (1988), are straightforward and are nearly
identical. For the APHA method, a small aliquot (50-300 [micro]l) of
whole blood that has been stabilized with ethylenediaminetetraacetate
(EDTA) is added to 1.0 ml 1MHNO3, vigorously shaken and
centrifuged. Aliquots (10-25 [micro]l) of the supernatant then are then
analyzed by graphite-furnace AAS with appropriate background correction.
Using the method of Stoeppler and Brandt (1980), aliquots (50-200
[micro]l) of whole blood that have been stabilized with EDTA are
pipetted into clean polystyrene tubes and mixed with 150-600 [micro]l of
1 M HNO3. After vigorous shaking, the solution is centrifuged
and a 10-25 [micro]l aliquot of the supernatant then is analyzed by
graphite-furnace AAS with appropriate background correction.
Claeys-Thoreau (1982) and DeBenzo et al. (1990) diluted blood
samples at a ratio of 1:10 with a matrix modifier (0.2% Triton X-100, a
wetting agent) for direct determinations of CDB. DeBenzo et al. also
demonstrated that aqueous standards of cadmium, instead of spiked,
whole-blood samples, could be used to establish calibration curves if
standards and samples are treated with additional small volumes of
matrix modifiers (i.e., 1% HNO3, 0.2% ammonium
hydrogenphosphate and 1 mg/ml magnesium salts).
These direct dilution procedures for CDB analysis are simple and
rapid. Laboratories can process more than 100 samples a day using a
dedicated graphite-furnace AAS, an auto-sampler, and either a Zeeman- or
a deuterium-background correction system. Several authors emphasize
using optimum settings for graphite-furnace temperatures during the
drying, charring, and atomization processes associated with the
flameless AAS method, and the need to run frequent QC samples when
performing automated analysis.
5.1.3 Sample Collection and Handling
Sample collection procedures are addressed primarily to identify
ways to minimize the degree of variability that may be introduced by
sample collection during medical monitoring. It is unclear at this point
the extent to which collection procedures contribute to variability
among CDB samples. Sources of variation that may result from sampling
procedures include time-of-day effects and introduction of external
contamination during the collection process. To minimize these sources,
strict adherence to a sample collection protocol is recommended. Such a
protocol must include provisions for thorough cleaning of the site from
which blood will be extracted; also, every effort should be made to
collect samples near the same time of day. It is also important to
recognize that under the recent OSHA blood-borne pathogens standard (29
CFR 1910.1030), blood samples and certain body fluids must be handled
and treated as if they are infectious.
5.1.4 Best Achievable Performance
The best achievable performance using a particular method for CDB
determinations is assumed to be equivalent to the performance reported
by research laboratories in which the method was developed.
For their method, Roberts and Clark (1986) demonstrated a limit of
detection of 0.4 [micro]g Cd/l in whole blood, with a linear response
curve from 0.4 to 16.0 [micro]g Cd/l. They report a coefficient of
variation (CV) of 6.7% at 8.0 [micro]g/l.
The APHA (1988) reports a range of 1.0-25 [micro]g/l, with a CV of
7.3% (concentration not stated). Insufficient documentation was
available to critique this method.
Stoeppler and Brandt (1980) achieved a detection limit of 0.2
[micro]g Cd/l whole blood, with a linear range of 0.4-12.0 [micro]g Cd/
l, and a CV of 15-30%, for samples at <1.0 [micro]g/l. Improved
precision (CV of 3.8%) was reported for CDB concentrations at 9.3
[micro]g/l.
5.1.5 General Method Performance
For any particular method, the performance expected from commercial
laboratories may be somewhat lower than that reported by the research
laboratory in which the method was developed. With participation in
appropriate proficiency programs and use of a proper in-house QA/QC
program incorporating provisions for regular corrective actions, the
performance of commercial laboratories is expected to approach that
reported by research laboratories. Also, the results reported for
existing proficiency programs serve as a gauge of the likely level of
performance that currently can be expected from commercial laboratories
offering these analyses.
Weber (1988) reports on the results of the proficiency program run
by the Centre de Toxicologie du Quebec (CTQ). As indicated previously,
participants in that program receive 18 blood samples per year having
cadmium concentrations ranging from 0.2-20 [micro]g/
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l. Currently, 76 laboratories are participating in this program. The
program is established for several analytes in addition to cadmium, and
not all of these laboratories participate in the cadmium proficiency-
testing program.
Under the CTQ program, cadmium results from individual laboratories
are compared against the consensus mean derived for each sample. Results
indicate that after receiving 60 samples (i.e., after participation for
approximately three years), 60% of the laboratories in the program are
able to report results that fall within 1
[micro]g/l or 15% of the mean, whichever is greater. (For this
procedure, the 15% criterion was applied to concentrations exceeding 7
[micro]g/l.) On any single sample of the last 20 samples, the percentage
of laboratories falling within the specified range is between 55 and
80%.
The CTQ also evaluates the performance of participating laboratories
against a less severe standard: 2 [micro]g/l or
15% of the mean, whichever is greater (Weber 1988); 90% of participating
laboratories are able to satisfy this standard after approximately 3
years in the program. (The 15% criterion is used for concentrations in
excess of 13 [micro]g/l.) On any single sample of the last 15 samples,
the percentage of laboratories falling within the specified range is
between 80 and 95% (except for a single test for which only 60% of the
laboratories achieved the desired performance).
Based on the data presented in Weber (1988), the CV for analysis of
CDB is nearly constant at 20% for cadmium concentrations exceeding 5
[micro]g/l, and increases for cadmium concentrations below 5 [micro]g/l.
At 2 [micro]g/l, the reported CV rises to approximately 40%. At 1
[micro]g/l, the reported CV is approximately 60%.
Participating laboratories also tend to overestimate concentrations
for samples exhibiting concentrations less than 2 [micro]g/l (see Figure
11 of Weber 1988). This problem is due in part to the proficiency
evaluation criterion that allows reporting a minimum 2.0 [micro]g/l for evaluated CDB samples. There is
currently little economic or regulatory incentive for laboratories
participating in the CTQ program to achieve greater accuracy for CDB
samples containing cadmium at concentrations less than 2.0 [micro]g/l,
even if the laboratory has the experience and competency to distinguish
among lower concentrations in the samples obtained from the CTQ.
The collective experience of international agencies and
investigators demonstrate the need for a vigorous QC program to ensure
that CDB values reported by participating laboratories are indeed
reasonably accurate. As Friberg (1988) stated:
``Information about the quality of published data has often been
lacking. This is of concern as assessment of metals in trace
concentrations in biological media are fraught with difficulties from
the collection, handling, and storage of samples to the chemical
analyses. This has been proven over and over again from the results of
interlaboratory testing and quality control exercises. Large variations
in results were reported even from `experienced' laboratories.''
The UNEP/WHO global study of cadmium biological monitoring set a
limit for CDB accuracy using the maximum allowable deviation method at
Y=X(0.1X+1) for a targeted concentration of 10
[micro]g Cd/l (Friberg and Vahter 1983). The performance of
participating laboratories over a concentration range of 1.5-12
[micro]g/l was reported by Lind et al. (1987). Of the 3 QC runs
conducted during 1982 and 1983, 1 or 2 of the 6 laboratories failed each
run. For the years 1983 and 1985, between zero and 2 laboratories failed
each of the consecutive QC runs.
In another study (Vahter and Friberg 1988), QC samples consisting of
both external (unknown) and internal (stated) concentrations were
distributed to laboratories participating in the epidemiology research.
In this study, the maximum acceptable deviation between the regression
analysis of reported results and reference values was set at Y=X(0.05X+0.2) for a concentration range of 0.3-5.0
[micro]g Cd/l. It is reported that only 2 of 5 laboratories had
acceptable data after the first QC set, and only 1 of 5 laboratories had
acceptable data after the second QC set. By the fourth QC set, however,
all 5 laboratories were judged proficient.
The need for high quality CDB monitoring is apparent when the
toxicological and biological characteristics of this metal are
considered; an increase in CDB from 2 to 4 [micro]g/l could cause a
doubling of the cadmium accumulation in the kidney, a critical target
tissue for selective cadmium accumulation (Nordberg and Nordberg 1988).
Historically, the CDC's internal QC program for CDB cadmium
monitoring program has found achievable accuracy to be 10% of the true value at CDB concentrations
=5.0 [micro]g/l (Paschal 1990). Data on the performance of
laboratories participating in this program currently are not available.
5.1.6 Observed CDB Concentrations
As stated in Section 4.3, CDB concentrations are representative of
ongoing levels of exposure to cadmium. Among those who have been exposed
chronically to cadmium for extended periods, however, CDB may contain a
component attributable to the general cadmium body burden.
5.1.6.1 CDB Concentrations Among Unexposed Samples
Numerous studies have been conducted examining CDB concentrations in
the general population, and in control groups used for comparison with
cadmium-exposed workers. A number of reports have been published that
present erroneously high values of CDB
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(Nordberg and Nordberg 1988). This problem was due to contamination of
samples during sampling and analysis, and to errors in analysis. Early
AAS methods were not sufficiently sensitive to accurately estimate CDB
concentrations.
Table 4 presents results of recent studies reporting CDB levels for
the general U.S. population not exposed occupationally to cadmium. Other
surveys of tissue cadmium using U.S. samples and conducted as part of a
cooperative effort among Japan, Sweden and the U.S., did not collect CDB
data because standard analytical methodologies were unavailable, and
because of analytic problems (Kjellstrom 1979; SWRI 1978).
Table 4--Blood Cadmium Concentrations of U.S. Population Not Occupationally Exposed to Cadmium \a\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Arithmetic mean Geometric mean Lower 95th Upper 95th
No. in Smoking habits ( S.D.) or (95% CI) \d\ thn-eq> GSD) \e\ distribution distribution Reference
(n) \c\ \f\ \f\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1........................... 80 M.............. 4 to 69........ NS,S........... 1.13............ 0.35-3.3....... 0.98.71.
88 F.............. 4 to 69........ NS,S........... 1.03............ 0.21-3.3....... 0.91.63.
115 M/F............ 4 to 69........ NS............. 0.95............ 0.21-3.3....... 0.85.59.
31 M/F............ 4 to 69........ S.............. 1.54............ 0.4-3.3........ 1.37.65.
2........................... 10 M.............. Adults......... (?)............ 2.0.1.
3........................... 24 M.............. Adults......... NS............. ................ ............... 0.6/87.
20 M.............. Adults......... S.............. ................ ............... 1.2.13.
64 F.............. Adults......... NS............. ................ ............... 0.5.85.
39 F.............. Adults......... S.............. ................ ............... 0.8.22.
4........................... 32 M.............. Adults......... S,NS........... ................ ............... 1.2.0.
5........................... 35 M.............. Adults......... (?)............ 2.1.1.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Concentrations reported in [micro]g Cd/l blood unless otherwise stated.
\b\ NS--never smoked; S--current cigarette smoker.
\c\ S.D.--Arithmetic Standard Deviation.
\d\ C.I.--Confidence interval.
\e\ GSD--Geometric Standard Deviation.
\f\ Based on an assumed lognormal distribution.
\g\ Based on an assumed normal distribution.
Arithmetic and/or geometric means and standard deviations are
provided in Table 4 for measurements among the populations defined in
each study listed. The range of reported measurements and/or the 95%
upper and lower confidence intervals for the means are presented when
this information was reported in a study. For studies reporting either
an arithmetic or geometric standard deviation along with a mean, the
lower and upper 95th percentile for the distribution also were derived
and reported in the table.
The data provided in table 4 from Kowal et al. (1979) are from
studies conducted between 1974 and 1976 evaluating CDB levels for the
general population in Chicago, and are considered to be representative
of the U.S. population. These studies indicate that the average CDB
concentration among those not occupationally exposed to cadmium is
approximately 1 [micro]g/l.
In several other studies presented in Table 4, measurements are
reported separately for males and females, and for smokers and
nonsmokers. The data in this table indicate that similar CDB levels are
observed among males and females in the general population, but that
smokers tend to exhibit higher CDB levels than nonsmokers. Based on the
Kowal et al. (1979) study, smokers not occupationally exposed to cadmium
exhibit an average CDB level of 1.4 [micro]g/l.
In general, nonsmokers tend to exhibit levels ranging to 2 [micro]g/
l, while levels observed among smokers range to 5 [micro]g/l. Based on
the data presented in Table 4, 95% of those not occupationally exposed
to cadmium exhibit CDB levels less than 5 [micro]g/l.
5.1.6.2 CDB concentrations among exposed workers
Table 5 is a summary of results from studies reporting CDB levels
among workers exposed to cadmium in the work place. As in Table 4,
arithmetic and/or geometric means and standard deviations are provided
if reported in the listed studies. The absolute range, or the 95%
confidence interval around the mean, of the data in each study are
provided when reported. In addition, the lower and upper 95th percentile
of the distribution are presented for each study i which a mean and
corresponding standard deviation were reported. Table 5 also provides
estimates of
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the duration, and level, of exposure to cadmium in the work place if
these data were reported in the listed studies. The data presented in
table 5 suggest that CDB levels are dose related. Sukuri et al. (1983)
show that higher CDB levels are observed among workers experiencing
higher work place exposure. This trend appears to be true of the studies
listed in the table.
CDB levels reported in table 5 are higher among those showing signs
of cadmium-related kidney damage than those showing no such damage.
Lauwerys et al. (1976) report CDB levels among workers with kidney
lesions that generally are above the levels reported for workers without
kidney lesions. Ellis et al. (1983) report a similar observation
comparing workers with and without renal dysfunction, although they
found more overlap between the 2 groups than Lauwerys et al.
Table 5--Blood Cadmium in Workers Exposed to Cadmium in the Workplace
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Concentrations of Cadmium in blood \a\
------------------------------------------------------------------------------------------------------------------------
Work environment Employment in Mean concentration Arithmetic mean
Study number (worker population Number in study years (mean) of cadmium in air ( S.D.) \b\ (95% C.I.) \c\ (GSD) \d\ percentile of percentile of Reference
range \e\ ( ) \f\ range \e\ ( ) \f\
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1.............................. Ni-Cd battery .................. 3-40.............. <=90.............. ................... .................. .................. .................. .................. Lauwerys et al.
plant and Cd 1976.
production plant:
(Workers without 96................ .................. .................. 21.41.9.
(Workers with 25................ .................. .................. 38.83.8.
2.............................. Ni-Cd battery .................. .................. .................. ................... .................. .................. .................. .................. Adamsson et al.
plant: (1979).
(Smokers)......... 7................. (5)............... 10.1.............. 22.7............... 7.3-67.2..........
(Nonsmokers)...... 8................. (9)............... 7.0............... 7.0................ 4.9-10.5..........
3.............................. Cadmium alloy .................. .................. .................. ................... .................. .................. .................. .................. Sukuri et al.
plant: 1982.
(High exposure 7................. (10.6)............ [1,000-5 yrs;..... 20.87.1.
(Low exposure 9................. (7.3)............. 40-5 yrs]......... 7.11.1.
4.............................. Retrospective 19................ 15-41............. .................. ................... .................. .................. .................. .................. Roels et al. 1982.
study of workers
with renal
problems:
(Before removal). .................. (27.2)............ .................. 39.93.7.
(After removal).. .................. \g\(4.2).......... .................. 14.15.6.
5.............................. Cadmium production .................. .................. .................. ................... .................. .................. .................. .................. Ellis et al. 1983.
plant:
(Workers without 33................ 1-34.............. .................. 155.7.
dysfunction).
(Workers with 18................ 10-34............. .................. 248.5.
dysfunction).
6.............................. Cd-Cu alloy plant. 75................ Up to 39.......... .................. ................... .................. 8.81.1.
7.............................. Cadmium recovery 45................ (19.0)............ .................. ................... .................. 7.92.0.
t (19) and former
(26) workers.
[[Page 206]]
8.............................. Cadmium recovery 40................ .................. .................. 10.25.3. 1989.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Concentrations reported in [micro]g Cd/l blood unless otherwise stated.
\b\ S.D.--Standard Deviation.
\c\ C.I.--Confidence Interval.
\d\ GSD--Geometric Standard Deviation.
\e\ Based on an assumed lognormal distribution.
\f\ Based on an assumed normal distribution.
\g\ Years following removal.
The data in table 5 also indicate that CDB levels are higher among
those experiencing current occupational exposure than those who have
been removed from such exposure. Roels et al. (1982) indicate that CDB
levels observed among workers experiencing ongoing exposure in the work
place are almost entirely above levels observed among workers removed
from such exposure. This finding suggests that CDB levels decrease once
cadmium exposure has ceased.
A comparison of the data presented in tables 4 and 5 indicates that
CDB levels observed among cadmium-exposed workers is significantly
higher than levels observed among the unexposed groups. With the
exception of 2 studies presented in table 5 (1 of which includes former
workers in the sample group tested), the lower 95th percentile for CDB
levels among exposed workers are greater than 5 [micro]g/l, which is the
value of the upper 95th percentile for CDB levels observed among those
who are not occupationally exposed. Therefore, a CDB level of 5
[micro]g/l represents a threshold above which significant work place
exposure to cadmium may be occurring.
5.1.7 Conclusions and Recommendations for CDB
Based on the above evaluation, the following recommendations are
made for a CDB proficiency program.
5.1.7.1 Recommended method
The method of Stoeppler and Brandt (1980) should be adopted for
analyzing CDB. This method was selected over other methods for its
straightforward sample-preparation procedures, and because limitations
of the method were described adequately. It also is the method used by a
plurality of laboratories currently participating in the CTQ proficiency
program. In a recent CTQ interlaboratory comparison report (CTQ 1991),
analysis of the methods used by laboratories to measure CDB indicates
that 46% (11 of 24) of the participating laboratories used the Stoeppler
and Brandt methodology (HNO3 deproteinization of blood
followed by analysis of the supernatant by GF-AAS). Other CDB methods
employed by participating laboratories identified in the CTQ report
include dilution of blood (29%), acid digestion (12%) and miscellaneous
methods (12%).
Laboratories may adopt alternate methods, but it is the
responsibility of the laboratory to demonstrate that the alternate
methods meet the data quality objectives defined for the Stoeppler and
Brandt method (see Section 5.1.7.2 below).
5.1.7.2 Data quality objectives
Based on the above evaluation, the following data quality objectives
(DQOs) should facilitate interpretation of analytical results.
Limit of Detection. 0.5 [micro]g/l should be achievable using the
Stoeppler and Brandt method. Stoeppler and Brandt (1980) report a limit
of detection equivalent to <=0.2 [micro]g/l in whole blood using 25
[micro]l aliquots of deproteinized, diluted blood samples.
Accuracy. Initially, some of the laboratories performing CDB
measurements may be expected to satisfy criteria similar to the less
severe criteria specified by the CTQ program, i.e., measurements within
2 [micro]g/l or 15% (whichever is greater) of the target value. About
60% of the laboratories enrolled in the CTQ program could meet this
criterion on the first proficiency test (Weber 1988).
Currently, approximately 12 laboratories in the CTQ program are
achieving an accuracy for CDB analysis within the more severe
constraints of 1 [micro]g/l or 15% (whichever is
greater). Later, as laboratories gain experience, they should achieve
the level of accuracy exhibited by these 12 laboratories. The experience
in the CTQ program has shown that, even without incentives, laboratories
benefit from the feedback of the program;
[[Page 207]]
after they have analyzed 40-50 control samples from the program,
performance improves to the point where about 60% of the laboratories
can meet the stricter criterion of 1 [micro]g/l or
15% (Weber 1988). Thus, this stricter target accuracy is a reasonable
DQO.
Precision. Although Stoeppler and Brandt (1980) suggest that a
coefficient of variation (CV) near 1.3% (for a 10 [micro]g/l
concentration) is achievable for within-run reproducibility, it is
recognized that other factors affecting within- and between-run
comparability will increase the achievable CV. Stoeppler and Brandt
(1980) observed CVs that were as high as 30% for low concentrations (0.4
[micro]g/l), and CVs of less than 5% for higher concentrations.
For internal QC samples (see Section 3.3.1), laboratories should
attain an overall precision near 25%. For CDB samples with
concentrations less than 2 [micro]g/l, a target precision of 40% is
reasonable, while precisions of 20% should be achievable for
concentrations greater than 2 [micro]g/l. Although these values are more
strict than values observed in the CTQ interlaboratory program reported
by Webber (1988), they are within the achievable limits reported by
Stoeppler and Brandt (1980).
5.1.7.3 Quality assurance/quality control
Commercial laboratories providing measurement of CDB should adopt an
internal QA/QC program that incorporates the following components:
Strict adherence to the selected method, including all calibration
requirements; regular incorporation of QC samples during actual runs; a
protocol for corrective actions, and documentation of these actions;
and, participation in an interlaboratory proficiency program. Note that
the nonmandatory QA/QC program presented in Attachment 1 is based on the
Stoeppler and Brandt method for CDB analysis. Should an alternate method
be adopted, the laboratory should develop a QA/QC program satisfying the
provisions of Section 3.3.1.
5.2 Measuring Cadmium in Urine (CDU)
As in the case of CDB measurement, proper determination of CDU
requires strict analytical discipline regarding collection and handling
of samples. Because cadmium is both ubiquitous in the environment and
employed widely in coloring agents for industrial products that may be
used during sample collection, preparation and analysis, care should be
exercised to ensure that samples are not contaminated during the
sampling procedure.
Methods for CDU determination share many of the same features as
those employed for the determination of CDB. Thus, changes and
improvements to methods for measuring CDU over the past 40 years
parallel those used to monitor CDB. The direction of development has
largely been toward the simplification of sample preparation techniques
made possible because of improvements in analytic techniques.
5.2.1 Units of CDU Measurement
Procedures adopted for reporting CDU concentrations are not uniform.
In fact, the situation for reporting CDU is more complicated than for
CDB, where concentrations are normalized against a unit volume of whole
blood.
Concentrations of solutes in urine vary with several biological
factors (including the time since last voiding and the volume of liquid
consumed over the last few hours); as a result, solute concentrations
should be normalized against another characteristic of urine that
represents changes in solute concentrations. The 2 most common
techniques are either to standardize solute concentrations against the
concentration of creatinine, or to standardize solute concentrations
against the specific gravity of the urine. Thus, CDU concentrations have
been reported in the literature as ``uncorrected'' concentrations of
cadmium per volume of urine (i.e., [micro]g Cd/l urine), ``corrected''
concentrations of cadmium per volume of urine at a standard specific
gravity (i.e., [micro]g Cd/l urine at a specific gravity of 1.020), or
``corrected'' mass concentration per unit mass of creatinine (i.e.,
[micro]g Cd/g creatinine). (CDU concentrations [whether uncorrected or
corrected for specific gravity, or normalized to creatinine]
occasionally are reported in nanomoles [i.e., nmoles] of cadmium per
unit mass or volume. In this protocol, these values are converted to
[micro]g of cadmium per unit mass or volume using 89 nmoles of
cadmium=10 [micro]g.)
While it is agreed generally that urine values of analytes should be
normalized for reporting purposes, some debate exists over what
correction method should be used. The medical community has long favored
normalization based on creatinine concentration, a common urinary
constituent. Creatinine is a normal product of tissue catabolism, is
excreted at a uniform rate, and the total amount excreted per day is
constant on a day-to-day basis (NIOSH 1984b). While this correction
method is accepted widely in Europe, and within some occupational health
circles, Kowals (1983) argues that the use of specific gravity (i.e.,
total solids per unit volume) is more straightforward and practical
(than creatinine) in adjusting CDU values for populations that vary by
age or gender.
Kowals (1983) found that urinary creatinine (CRTU) is lower in
females than males, and also varies with age. Creatinine excretion is
highest in younger males (20-30 years old), decreases at middle age (50-
60 years), and
[[Page 208]]
may rise slightly in later years. Thus, cadmium concentrations may be
underestimated for some workers with high CRTU levels.
Within a single void urine collection, urine concentration of any
analyte will be affected by recent consumption of large volumes of
liquids, and by heavy physical labor in hot environments. The absolute
amount of analyte excreted may be identical, but concentrations will
vary widely so that urine must be corrected for specific gravity (i.e.,
to normalize concentrations to the quantity of total solute) using a
fixed value (e.g., 1.020 or 1.024). However, since heavy-metal exposure
may increase urinary protein excretion, there is a tendency to
underestimate cadmium concentrations in samples with high specific
gravities when specific-gravity corrections are applied.
Despite some shortcomings, reporting solute concentrations as a
function of creatinine concentration is accepted generally; OSHA
therefore recommends that CDU levels be reported as the mass of cadmium
per unit mass of creatinine ([micro]g/g CTRU).
Reporting CDU as [micro]g/g CRTU requires an additional analytical
process beyond the analysis of cadmium: Samples must be analyzed
independently for creatinine so that results may be reported as the
ratio of cadmium to creatinine concentrations found in the urine sample.
Consequently, the overall quality of the analysis depends on the
combined performance by a laboratory on these 2 determinations. The
analysis used for CDU determinations is addressed below in terms of
[micro]g Cd/l, with analysis of creatinine addressed separately.
Techniques for assessing creatinine are discussed in Section 5.4.
Techniques for deriving cadmium as a ratio of CRTU, and the
confidence limits for independent measurements of cadmium and CRTU, are
provided in Section 3.3.3.
5.2.2 Analytical Techniques Used To Monitor CDU
Analytical techniques used for CDU determinations are similar to
those employed for CDB determinations; these techniques are summarized
in Table 3. As with CDB monitoring, the technique most suitable for CDU
determinations is atomic absorption spectroscopy (AAS). AAS methods used
for CDU determinations typically employ a graphite furnace, with
background correction made using either the deuterium-lamp or Zeeman
techniques; Section 5.1.1 provides a detailed description of AAS
methods.
5.2.3 Methods Developed for CDU Determinations
Princi (1947), Smith et al. (1955), Smith and Kench (1957), and
Tsuchiya (1967) used colorimetric procedures similar to those described
in the CDB section above to estimate CDU concentrations. In these
methods, urine (50 ml) is reduced to dryness by heating in a sand bath
and digested (wet ashed) with mineral acids. Cadmium then is complexed
with dithiazone, extracted with chloroform and quantified by
spectrophotometry. These early studies typically report reagent blank
values equivalent to 0.3 [micro]g Cd/l, and CDU concentrations among
nonexposed control groups at maximum levels of 10 [micro]g Cd/l--
erroneously high values when compared to more recent surveys of cadmium
concentrations in the general population.
By the mid-1970s, most analytical procedures for CDU analysis used
either wet ashing (mineral acid) or high temperatures (400
[deg]C) to digest the organic matrix of urine, followed by cadmium
chelation with APDC or DDTC solutions and extraction with MIBK. The
resulting aliquots were analyzed by flame or graphite-furnace AAS
(Kjellstrom 1979).
Improvements in control over temperature parameters with
electrothermal heating devices used in conjunction with flameless AAS
techniques, and optimization of temperature programs for controlling the
drying, charring, and atomization processes in sample analyses, led to
improved analytical detection of diluted urine samples without the need
for sample digestion or ashing. Roels et al. (1978) successfully used a
simple sample preparation, dilution of 1.0 ml aliquots of urine with 0.1
N HNO3, to achieve accurate low-level determinations of CDU.
In the method described by Pruszkowska et al. (1983), which has
become the preferred method for CDU analysis, urine samples were diluted
at a ratio of 1:5 with water; diammonium hydrogenphosphate in dilute
HNO3 was used as a matrix modifier. The matrix modifier
allows for a higher charring temperature without loss of cadmium through
volatilization during preatomization. This procedure also employs a
stabilized temperature platform in a graphite furnace, while nonspecific
background absorbtion is corrected using the Zeeman technique. This
method allows for an absolute detection limit of approximately 0.04
[micro]g Cd/l urine.
5.2.4 Sample Collection and Handling
Sample collection procedures for CDU may contribute to variability
observed among CDU measurements. Sources of variation attendant to
sampling include time-of-day, the interval since ingestion of liquids,
and the introduction of external contamination during the collection
process. Therefore, to minimize contributions from these variables,
strict adherence to a sample-collection protocol is recommended. This
protocol should include provisions for normalizing the conditions under
which urine is collected. Every effort also should be made to collect
samples during the same time of day.
[[Page 209]]
Collection of urine samples from an industrial work force for
biological monitoring purposes usually is performed using ``spot''
(i.e., single-void) urine with the pH of the sample determined
immediately. Logistic and sample-integrity problems arise when efforts
are made to collect urine over long periods (e.g., 24 hrs). Unless
single-void urines are used, there are numerous opportunities for
measurement error because of poor control over sample collection,
storage and environmental contamination.
To minimize the interval during which sample urine resides in the
bladder, the following adaption to the ``spot'' collection procedure is
recommended: The bladder should first be emptied, and then a large glass
of water should be consumed; the sample may be collected within an hour
after the water is consumed.
5.2.5 Best Achievable Performance
Performance using a particular method for CDU determinations is
assumed to be equivalent to the performance reported by the research
laboratories in which the method was developed. Pruszkowska et al.
(1983) report a detection limit of 0.04 [micro]g/l CDU, with a CV of <4%
between 0-5 [micro]g/l. The CDC reports a minimum CDU detection limit of
0.07 [micro]g/l using a modified method based on Pruszkowska et al.
(1983). No CV is stated in this protocol; the protocol contains only
rejection criteria for internal QC parameters used during accuracy
determinations with known standards (Attachment 8 of exhibit 106 of OSHA
docket H057A). Stoeppler and Brandt (1980) report a CDU detection limit
of 0.2 [micro]/l for their methodology.
5.2.6 General Method Performance
For any particular method, the expected initial performance from
commercial laboratories may be somewhat lower than that reported by the
research laboratory in which the method was developed. With
participation in appropriate proficiency programs, and use of a proper
in-house QA/QC program incorporating provisions for regular corrective
actions, the performance of commercial laboratories may be expected to
improve and approach that reported by a research laboratories. The
results reported for existing proficiency programs serve to specify the
initial level of performance that likely can be expected from commercial
laboratories offering analysis using a particular method.
Weber (1988) reports on the results of the CTQ proficiency program,
which includes CDU results for laboratories participating in the
program. Results indicate that after receiving 60 samples (i.e., after
participating in the program for approximately 3 years), approximately
80% of the participating laboratories report CDU results ranging between
2 [micro]g/l or 15% of the consensus mean,
whichever is greater. On any single sample of the last 15 samples, the
proportion of laboratories falling within the specified range is between
75 and 95%, except for a single test for which only 60% of the
laboratories reported acceptable results. For each of the last 15
samples, approximately 60% of the laboratories reported results within
1 [micro]g or 15% of the mean, whichever is
greater. The range of concentrations included in this set of samples was
not reported.
Another report from the CTQ (1991) summarizes preliminary CDU
results from their 1991 interlaboratory program. According to the
report, for 3 CDU samples with values of 9.0, 16.8, 31.5 [micro]g/l,
acceptable results (target of 2 [micro]g/l or 15 %
of the consensus mean, whichever is greater) were achieved by only 44-
52% of the 34 laboratories participating in the CDU program. The overall
CVs for these 3 CDU samples among the 34 participating laboratories were
31%, 25%, and 49%, respectively. The reason for this poor performance
has not been determined.
A more recent report from the CTQ (Weber, private communication)
indicates that 36% of the laboratories in the program have been able to
achieve the target of 1 [micro]g/l or 15% for more
than 75% of the samples analyzed over the last 5 years, while 45% of
participating laboratories achieved a target of 2
[micro]g/l or 15% for more than 75% of the samples analyzed over the
same period.
Note that results reported in the interlaboratory programs are in
terms of [micro]g Cd/l of urine, unadjusted for creatinine. The
performance indicated, therefore, is a measure of the performance of the
cadmium portion of the analyses, and does not include variation that may
be introduced during the analysis of CRTU.
5.2.7 Observed CDU Concentrations
Prior to the onset of renal dysfunction, CDU concentrations provide
a general indication of the exposure history (i.e., body burden) (see
Section 4.3). Once renal dysfunction occurs, CDU levels appear to
increase and are no longer indicative solely of cadmium body burden
(Friberg and Elinder 1988).
5.2.7.1 Range of CDU concentrations observed among unexposed samples
Surveys of CDU concentrations in the general population were first
reported from cooperative studies among industrial countries (i.e.,
Japan, U.S. and Sweden) conducted in the mid-1970s. In summarizing these
data, Kjellstrom (1979) reported that CDU concentrations among Dallas,
Texas men (age range: <9-59 years; smokers and nonsmokers) varied from
0.11-1.12 [micro]g/l (uncorrected for creatinine or specific gravity).
These CDU concentrations are intermediate between population values
found in Sweden (range: 0.11-0.80 [micro]g/l) and Japan (range: 0.14-
2.32 [micro]g/l).
[[Page 210]]
Kowal and Zirkes (1983) reported CDU concentrations for almost 1,000
samples collected during 1978-79 from the general U.S. adult population
(i.e., nine states; both genders; ages 20-74 years). They report that
CDU concentrations are lognormally distributed; low levels predominated,
but a small proportion of the population exhibited high levels. These
investigators transformed the CDU concentrations values, and reported
the same data 3 different ways: [micro]g/l urine (unadjusted), [micro]g/
l (specific gravity adjusted to 1.020), and [micro]g/g CRTU. These data
are summarized in Tables 6 and 7.
Based on further statistical examination of these data, including
the lifestyle characteristics of this group, Kowal (1988) suggested
increased cadmium absorption (i.e., body burden) was correlated with low
dietary intakes of calcium and iron, as well as cigarette smoking.
CDU levels presented in Table 6 are adjusted for age and gender.
Results suggest that CDU levels may be slightly different among men and
women (i.e., higher among men when values are unadjusted, but lower
among men when the values are adjusted, for specific gravity or CRTU).
Mean differences among men and women are small compared to the standard
deviations, and therefore may not be significant. Levels of CDU also
appear to increase with age. The data in Table 6 suggest as well that
reporting CDU levels adjusted for specific gravity or as a function of
CRTU results in reduced variability.
Table 6--Urine Cadmium Concentrations in the U.S. Adult Population: Normal and Concentration-Adjusted Values by
Age and Sex \1\
----------------------------------------------------------------------------------------------------------------
Geometric means (and geometric standard
deviations)
-----------------------------------------------
SG-adjusted Creatine-
Unadjusted \2\ [micro]g/l adjusted
([micro]g/l) at 1.020) ([micro]g/g)
----------------------------------------------------------------------------------------------------------------
Sex:
Male (n=484)................................................ 0.55 (2.9) 0.73 (2.6) 0.55 (2.7)
Female (n=498).............................................. 0.49 (3.0) 0.86 (2.7) 0.78 (2.7)
Age:
20-29 (n=222)............................................... 0.32 (3.0) 0.43 (2.7) 0.32 (2.7)
30-39 (n=141)............................................... 0.46 (3.2) 0.70 (2.8) 0.54 (2.7)
40-49 (n=142)............................................... 0.50 (3.0) 0.81 (2.6) 0.70 (2.7)
50-59 (n=117)............................................... 0.61 (2.9) 0.99 (2.4) 0.90 (2.3)
60-69 (n=272)............................................... 0.76 (2.6) 1.16 (2.3) 1.03 (2.3)
----------------------------------------------------------------------------------------------------------------
\1\ From Kowal and Zirkes 1983.
\2\ SC-adjusted is adjusted for specific gravity.
Table 7--Urine Cadmium Concentrations in the U.S. Adult Population: Cumulative Frequency Distribution of Urinary
Cadmium (N=982) \1\
----------------------------------------------------------------------------------------------------------------
Creatine-
Unadjusted SG-adjusted adjusted
Range of concentrations ([micro]g/l) ([micro]g/l at ([micro]g/g)
percent 1.020) percent percent
----------------------------------------------------------------------------------------------------------------
<0.5............................................................ 43.9 28.0 35.8
0.6-1.0........................................................ 71.7 56.4 65.6
1.1-1.5........................................................ 84.4 74.9 81.4
1.6-2.0........................................................ 91.3 84.7 88.9
2.1-3.0........................................................ 97.3 94.4 95.8
3.1-4.0........................................................ 98.8 97.4 97.2
4.1-5.0........................................................ 99.4 98.2 97.9
5.1-10.0....................................................... 99.6 99.4 99.3
10.0-20.0...................................................... 99.8 99.6 99.6
----------------------------------------------------------------------------------------------------------------
\1\ Source: Kowal and Zirkes (1983).
The data in the Table 6 indicate the geometric mean of CDU levels
observed among the general population is 0.52 [micro]/g Cd/l urine
(unadjusted), with a geometric standard deviation of 3.0. Normalized for
creatinine, the geometric mean for the population is 0.66 [micro]/g
CRTU, with a geometric standard deviation of 2.7. Table 7 provides the
distributions of CDU concentrations for the general population studied
by Kowal and Zirkes. The data in this table indicate that 95% of the
[[Page 211]]
CDU levels observed among those not occupationally exposed to cadmium
are below 3 [micro]/g CRTU.
5.2.7.2 Range of CDU concentrations observed among exposed workers
Table 8 is a summary of results from available studies of CDU
concentrations observed among cadmium-exposed workers. In this table,
arithmetic and/or geometric means and standard deviations are provided
if reported in these studies. The absolute range for the data in each
study, or the 95% confidence interval around the mean of each study,
also are provided when reported. The lower and upper 95th percentile of
the distribution are presented for each study in which a mean and
corresponding standard deviation were reported. Table 8 also provides
estimates of the years of exposure, and the levels of exposure, to
cadmium in the work place if reported in these studies. Concentrations
reported in this table are in [micro]/g CRTU, unless otherwise stated.
[[Page 212]]
Table 8--Urine Cadmium Concentrations in Workers Exposed to Cadmium in the Workplace
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Concentration of cadmium in Urine \a\
------------------------------------------------------------------------------------------------------------------------
Work environment Number in Study Employment in Mean Concentration Arithmetic mean
Study number (worker population (n) years (mean) of cadmium in air ( S.D.) \b\ (95% C.I.) \c\ (GSD) \d\ percentile of percentile of Reference
range \e\ ( ) \f\ range \e\ ( ) \f\
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1.............................. Ni-Cd battery .................. 3-40.............. <= 90............. ................... .................. .................. .................. .................. Lauwerys et al.
plant and Cd 1976.
production plant.
(Workers without 96................ .................. .................. 16.316.7.
(Workers with 25................ .................. .................. 48.242.6.
2.............................. Ni-Cd battery .................. .................. .................. ................... .................. .................. .................. .................. Adamsson et al.
plant. (1979).
(Smokers)........ 7................. (5)............... 10.1.............. 5.5................ 1.0-14.7..........
(Nonsmokers)..... 8................. (9)............... 7.0............... 3.6................ 0.5-9.3...........
3.............................. Cadmium salts 148............... (15.4)............ .................. 15.8............... 2-150............. .................. .................. .................. Butchet et al.
production 1980.
facility.
4.............................. Retrospective 19................ 15-41............. .................. ................... .................. .................. .................. .................. Roels et al. 1982.
study of workers
with renal
problems.
(Before removal). .................. (27.2)............ .................. 39.428.1.
(After removal).. .................. (4.2) \g\......... .................. 16.49.0.
5.............................. Cadmium production .................. .................. .................. ................... .................. .................. .................. .................. Ellis et al. 1983.
plant.
(Workers without 33................ 1-34.............. .................. 9.46.9.
dysfunction).
(Workers with 18................ 10-34............. .................. 22.812.7.
dysfunction).
6.............................. Cd-Cu alloy plant. 75................ Up to 39.......... Note h............ 6.99.4.
7.............................. Cadmium recovery 45................ (19).............. 87................ 9.36.9.
8.............................. Pigment 29................ (12.8)............ 0.18-3.0.......... ................... 0.2-9.5........... 1.1............... .................. .................. Mueller et al.
manufacturing 1989.
plant.
9.............................. Pigment 26................ (12.1)............ <=3.0............. ................... .................. 1.252.45. 1990.
plant.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Concentrations reported in [micro]g/g Cr.
\b\ S.D.--Standard Deviation.
\c\ C.I.--Confidence Interval.
\d\ GSD--Geometric Standard Deviation.
\e\ Based on an assumed lognormal distribution.
\f\ Based on an assumed normal distribution.
\g\ Years following removal.
\h\ Equivalent to 50 for 20-22 yrs
[[Page 213]]
Data in Table 8 from Lauwerys et al. (1976) and Ellis et al. (1983)
indicate that CDU concentrations are higher among those exhibiting
kidney lesions or dysfunction than among those lacking these symptoms.
Data from the study by Roels et al. (1982) indicate that CDU levels
decrease among workers removed from occupational exposure to cadmium in
comparison to workers experiencing ongoing exposure. In both cases,
however, the distinction between the 2 groups is not as clear as with
CDB; there is more overlap in CDU levels observed among each of the
paired populations than is true for corresponding CDB levels. As with
CDB levels, the data in Table 8 suggest increased CDU concentrations
among workers who experienced increased overall exposure.
Although a few occupationally-exposed workers in the studies
presented in Table 8 exhibit CDU levels below 3 [micro]g/g CRTU, most of
those workers exposed to cadmium levels in excess of the PEL defined in
the final cadmium rule exhibit CDU levels above 3 [micro]g/g CRTU; this
level represents the upper 95th percentile of the CDU distribution
observed among those who are not occupationally exposed to cadmium
(Table 7).
The mean CDU levels reported in Table 8 among occupationally-exposed
groups studied (except 2) exceed 3 [micro]g/g CRTU. Correspondingly, the
level of exposure reported in these studies (with 1 exception) are
significantly higher than what workers will experience under the final
cadmium rule. The 2 exceptions are from the studies by Mueller et al.
(1989) and Kawada et al. (1990); these studies indicate that workers
exposed to cadmium during pigment manufacture do not exhibit CDU levels
as high as those levels observed among workers exposed to cadmium in
other occupations. Exposure levels, however, were lower in the pigment
manufacturing plants studied. Significantly, workers removed from
occupational cadmium exposure for an average of 4 years still exhibited
CDU levels in excess of 3 [micro]g/g CRTU (Roels et al. 1982). In the
single-exception study with a reported level of cadmium exposure lower
than levels proposed in the final rule (i.e., the study of a pigment
manufacturing plant by Kawada et al. 1990), most of the workers
exhibited CDU levels less than 3 [micro]g/g CRTU (i.e., the mean value
was only 1.3 [micro]g/g CRTU). CDU levels among workers with such
limited cadmium exposure are expected to be significantly lower than
levels of other studies reported in Table 8.
Based on the above data, a CDU level of 3 [micro]g/g CRTU appear to
represent a threshold above which significant work place exposure to
cadmium occurs over the work span of those being monitored. Note that
this threshold is not as distinct as the corresponding threshold
described for CDB. In general, the variability associated with CDU
measurements among exposed workers appears to be higher than the
variability associated with CDB measurements among similar workers.
5.2.8 Conclusions and Recommendations for CDU
The above evaluation supports the following recommendations for a
CDU proficiency program. These recommendations address only sampling and
analysis procedures for CDU determinations specifically, which are to be
reported as an unadjusted [micro]g Cd/l urine. Normalizing this result
to creatinine requires a second analysis for CRTU so that the ratio of
the 2 measurements can be obtained. Creatinine analysis is addressed in
Section 5.4. Formal procedures for combining the 2 measurements to
derive a value and a confidence limit for CDU in [micro]g/g CRTU are
provided in Section 3.3.3.
5.2.8.1 Recommended method
The method of Pruszkowska et al. (1983) should be adopted for CDU
analysis. This method is recommended because it is simple,
straightforward and reliable (i.e., small variations in experimental
conditions do not affect the analytical results).
A synopsis of the methods used by laboratories to determine CDU
under the interlaboratory program administered by the CTQ (1991)
indicates that more than 78% (24 of 31) of the participating
laboratories use a dilution method to prepare urine samples for CDU
analysis. Laboratories may adopt alternate methods, but it is the
responsibility of the laboratory to demonstrate that the alternate
methods provide results of comparable quality to the Pruszkowska method.
5.2.8.2 Data quality objectives
The following data quality objectives should facilitate
interpretation of analytical results, and are achievable based on the
above evaluation.
Limit of Detection. A level of 0.5 [micro]g/l (i.e., corresponding
to a detection limit of 0.5 [micro]g/g CRTU, assuming 1 g CRT/l urine)
should be achievable. Pruszkowska et al. (1983) achieved a limit of
detection of 0.04 [micro]g/l for CDU based on the slope of the curve for
their working standards (0.35 pg Cd/0.0044, A signal=1% absorbance using
GF-AAS).
The CDC reports a minimum detection limit for CDU of 0.07 [micro]g/l
using a modified Pruszkowska method. This limit of detection was defined
as 3 times the standard deviation calculated from 10 repeated
measurements of a ``low level'' CDU test sample (Attachment 8 of exhibit
106 of OSHA docket H057A).
Stoeppler and Brandt (1980) report a limit of detection for CDU of
0.2 [micro]g/l using an aqueous dilution (1:2) of the urine samples.
Accuracy. A recent report from the CTQ (Weber, private
communication) indicates that 36% of the laboratories in the program
[[Page 214]]
achieve the target of 1 [micro]g/l or 15% for more
than 75% of the samples analyzed over the last 5 years, while 45% of
participating laboratories achieve a target of 2
[micro]g/l or 15% for more than 75% of the samples analyzed over the
same period. With time and a strong incentive for improvement, it is
expected that the proportion of laboratories successfully achieving the
stricter level of accuracy should increase. It should be noted, however,
these indices of performance do not include variations resulting from
the ancillary measurement of CRTU (which is recommended for the proper
recording of results). The low cadmium levels expected to be measured
indicate that the analysis of creatinine will contribute relatively
little to the overall variability observed among creatinine-normalized
CDU levels (see Section 5.4). The initial target value for reporting CDU
under this program, therefore, is set at 1
[micro]g/g CRTU or 15% (whichever is greater).
Precision. For internal QC samples (which are recommended as part of
an internal QA/QC program, Section 3.3.1), laboratories should attain an
overall precision of 25%. For CDB samples with concentrations less than
2 [micro]g/l, a target precision of 40% is acceptable, while precisions
of 20% should be achievable for CDU concentrations greater than 2
[micro]g/l. Although these values are more stringent than those observed
in the CTQ interlaboratory program reported by Webber (1988), they are
well within limits expected to be achievable for the method as reported
by Stoeppler and Brandt (1980).
5.2.8.3 Quality assurance/quality control
Commercial laboratories providing CDU determinations should adopt an
internal QA/QC program that incorporates the following components:
Strict adherence to the selected method, including calibration
requirements; regular incorporation of QC samples during actual runs; a
protocol for corrective actions, and documentation of such actions; and,
participation in an interlaboratory proficiency program. Note that the
nonmandatory program presented in Attachment 1 as an example of an
acceptable QA/QC program, is based on using the Pruszkowska method for
CDU analysis. Should an alternate method be adopted by a laboratory, the
laboratory should develop a QA/QC program equivalent to the nonmandatory
program, and which satisfies the provisions of Section 3.3.1.
5.3 Monitoring [beta]-2-Microglobulin in Urine (B2MU)
As indicated in Section 4.3, B2MU appears to be the best of several
small proteins that may be monitored as early indicators of cadmium-
induced renal damage. Several analytic techniques are available for
measuring B2M.
5.3.1 Units of B2MU Measurement
Procedures adopted for reporting B2MU levels are not uniform. In
these guidelines, OSHA recommends that B2MU levels be reported as
[micro]g/g CRTU, similar to reporting CDU concentrations. Reporting B2MU
normalized to the concentration of CRTU requires an additional
analytical process beyond the analysis of B2M: Independent analysis for
creatinine so that results may be reported as a ratio of the B2M and
creatinine concentrations found in the urine sample. Consequently, the
overall quality of the analysis depends on the combined performance on
these 2 analyses. The analysis used for B2MU determinations is described
in terms of [micro]g B2M/l urine, with analysis of creatinine addressed
separately. Techniques used to measure creatinine are provided in
Section 5.4. Note that Section 3.3.3 provides techniques for deriving
the value of B2M as function of CRTU, and the confidence limits for
independent measurements of B2M and CRTU.
5.3.2 Analytical Techniques Used To Monitor B2MU
One of the earliest tests used to measure B2MU was the radial
immunodiffusion technique. This technique is a simple and specific
method for identification and quantitation of a number of proteins found
in human serum and other body fluids when the protein is not readily
differentiated by standard electrophoretic procedures. A quantitative
relationship exists between the concentration of a protein deposited in
a well that is cut into a thin agarose layer containing the
corresponding monospecific antiserum, and the distance that the
resultant complex diffuses. The wells are filled with an unknown serum
and the standard (or control), and incubated in a moist environment at
room temperature. After the optimal point of diffusion has been reached,
the diameters of the resulting precipition rings are measured. The
diameter of a ring is related to the concentration of the constituent
substance. For B2MU determinations required in the medical monitoring
program, this method requires a process that may be insufficient to
concentrate the protein to levels that are required for detection.
Radioimmunoassay (RIA) techniques are used widely in immunologic
assays to measure the concentration of antigen or antibody in body-fluid
samples. RIA procedures are based on competitive-binding techniques. If
antigen concentration is being measured, the principle underlying the
procedure is that radioactive-labeled antigen competes with the sample's
unlabeled antigen for binding sites on a known amount of immobile
antibody. When these 3 components are present in the system, an
equilibrium exists. This equilibrium is followed by a separation of
[[Page 215]]
the free and bound forms of the antigen. Either free or bound
radioactive-labeled antigen can be assessed to determine the amount of
antigen in the sample. The analysis is performed by measuring the level
of radiation emitted either by the bound complex following removal of
the solution containing the free antigen, or by the isolated solution
containing the residual-free antigen. The main advantage of the RIA
method is the extreme sensitivity of detection for emitted radiation and
the corresponding ability to detect trace amounts of antigen.
Additionally, large numbers of tests can be performed rapidly.
The enzyme-linked immunosorbent assay (ELISA) techniques are similar
to RIA techniques except that nonradioactive labels are employed. This
technique is safe, specific and rapid, and is nearly as sensitive as RIA
techniques. An enzyme-labeled antigen is used in the immunologic assay;
the labeled antigen detects the presence and quantity of unlabeled
antigen in the sample. In a representative ELISA test, a plastic plate
is coated with antibody (e.g., antibody to B2M). The antibody reacts
with antigen (B2M) in the urine and forms an antigen-antibody complex on
the plate. A second anti-B2M antibody (i.e., labeled with an enzyme) is
added to the mixture and forms an antibody-antigen-antibody complex.
Enzyme activity is measured spectrophotometrically after the addition of
a specific chromogenic substrate which is activated by the bound enzyme.
The results of a typical test are calculated by comparing the
spectrophotometric reading of a serum sample to that of a control or
reference serum. In general, these procedures are faster and require
less laboratory work than other methods.
In a fluorescent ELISA technique (such as the one employed in the
Pharmacia Delphia test for B2M), the labeled enzyme is bound to a strong
fluorescent dye. In the Pharmacia Delphia test, an antigen bound to a
fluorescent dye competes with unlabeled antigen in the sample for a
predetermined amount of specific, immobile antibody. Once equilibrium is
reached, the immobile phase is removed from the labeled antigen in the
sample solution and washed; an enhancement solution then is added that
liberates the fluorescent dye from the bound antigen-antibody complex.
The enhancement solution also contains a chelate that complexes with the
fluorescent dye in solution; this complex increases the fluorescent
properties of the dye so that it is easier to detect.
To determine the quantity of B2M in a sample using the Pharmacia
Delphia test, the intensity of the fluorescence of the enhancement
solution is measured. This intensity is proportional to the
concentration of labeled antigen that bound to the immobile antibody
phase during the initial competition with unlabeled antigen from the
sample. Consequently, the intensity of the fluorescence is an inverse
function of the concentration of antigen (B2M) in the original sample.
The relationship between the fluorescence level and the B2M
concentration in the sample is determined using a series of graded
standards, and extrapolating these standards to find the concentration
of the unknown sample.
5.3.3 Methods Developed for B2MU Determinations
B2MU usually is measured by radioimmunoassay (RIA) or enzyme-linked
immunosorbent assay (ELISA); however, other methods (including gel
electrophoresis, radial immunodiffusion, and nephelometric assays) also
have been described (Schardun and van Epps 1987). RIA and ELISA methods
are preferred because they are sensitive at concentrations as low as
micrograms per liter, require no concentration processes, are highly
reliable and use only a small sample volume.
Based on a survey of the literature, the ELISA technique is
recommended for monitoring B2MU. While RIAs provide greater sensitivity
(typically about 1 [micro]g/l, Evrin et al. 1971), they depend on the
use of radioisotopes; use of radioisotopes requires adherence to rules
and regulations established by the Atomic Energy Commission, and
necessitates an expensive radioactivity counter for testing.
Radioisotopes also have a relatively short half-life, which corresponds
to a reduced shelf life, thereby increasing the cost and complexity of
testing. In contrast, ELISA testing can be performed on routine
laboratory spectrophotometers, do not necessitate adherence to
additional rules and regulations governing the handling of radioactive
substances, and the test kits have long shelf lives. Further, the range
of sensitivity commonly achieved by the recommended ELISA test (i.e.,
the Pharmacia Delphia test) is approximately 100 [micro]g/l (Pharmacia
1990), which is sufficient for monitoring B2MU levels resulting from
cadmium exposure. Based on the studies listed in Table 9 (Section
5.3.7), the average range of B2M concentrations among the general,
nonexposed population falls between 60 and 300 [micro]g/g CRTU. The
upper 95th percentile of distributions, derived from studies in Table 9
which reported standard deviations, range between 180 and 1,140
[micro]g/g CRTU. Also, the Pharmacia Delphia test currently is the most
widely used test for assessing B2MU.
[[Page 216]]
5.3.4 Sample Collection and Handling
As with CDB or CDU, sample collection procedures are addressed
primarily to identify ways to minimize the degree of variability
introduced by sample collection during medical monitoring. It is unclear
the extent to which sample collection contributes to B2MU variability.
Sources of variation include time-of-day effects, the interval since
consuming liquids and the quantity of liquids consumed, and the
introduction of external contamination during the collection process. A
special problem unique to B2M sampling is the sensitivity of this
protein to degradation under acid conditions commonly found in the
bladder. To minimize this problem, strict adherence to a sampling
protocol is recommended. The protocol should include provisions for
normalizing the conditions under which the urine is collected. Clearly,
it is important to minimize the interval urine spends in the bladder. It
also is recommended that every effort be made to collect samples during
the same time of day.
Collection of urine samples for biological monitoring usually is
performed using ``spot'' (i.e., single-void) urine. Logistics and sample
integrity become problems when efforts are made to collect urine over
extended periods (e.g., 24 hrs). Unless single-void urines are used,
numerous opportunities exist for measurement error because of poor
control over sample collection, storage and environmental contamination.
To minimize the interval that sample urine resides in the bladder,
the following adaption to the ``spot'' collection procedure is
recommended: The bladder should be emptied and then a large glass of
water should be consumed; the sample then should be collected within an
hour after the water is consumed.
5.3.5 Best Achievable Performance
The best achievable performance is assumed to be equivalent to the
performance reported by the manufacturers of the Pharmacia Delphia test
kits (Pharmacia 1990). According to the insert that comes with these
kits, QC results should be within 2 SDs of the
mean for each control sample tested; a CV of less than or equal to 5.2%
should be maintained. The total CV reported for test kits is less than
or equal to 7.2%.
5.3.6 General Method Performance
Unlike analyses for CDB and CDU, the Pharmacia Delphia test is
standardized in a commercial kit that controls for many sources of
variation. In the absence of data to the contrary, it is assumed that
the achievable performance reported by the manufacturer of this test kit
will serve as an achievable performance objective. The CTQ proficiency
testing program for B2MU analysis is expected to use the performance
parameters defined by the test kit manufacturer as the basis of the B2MU
proficiency testing program.
Note that results reported for the test kit are expressed in terms
of [micro]g B2M/l of urine, and have not been adjusted for creatinine.
The indicated performance, therefore, is a measure of the performance of
the B2M portion of the analyses only, and does not include variation
that may have been introduced during the analysis of creatinine.
5.3.7 Observed B2MU Concentrations
As indicated in Section 4.3, the concentration of B2MU may serve as
an early indicator of the onset of kidney damage associated with cadmium
exposure.
5.3.7.1 Range of B2MU concentrations among unexposed samples
Most of the studies listed in Table 9 report B2MU levels for those
who were not occupationally exposed to cadmium. Studies noted in the
second column of this table (which contain the footnote ``d'') reported
B2MU concentrations among cadmium-exposed workers who, nonetheless,
showed no signs of proteinuria. These latter studies are included in
this table because, as indicated in Section 4.3, monitoring B2MU is
intended to provide advanced warning of the onset of kidney dysfunction
associated with cadmium exposure, rather than to distinguish relative
exposure. This table, therefore, indicates the range of B2MU levels
observed among those who had no symptoms of renal dysfunction (including
cadmium-exposed workers with none of these symptoms).
Table 9--B-2-Microglobulin Concentrations Observed in Urine Among Those not Occupationally Exposed to Cadmium
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Lower 95th Upper 95th
Study No. No. in study Geometric mean Geometric standard percentile of percentile of Reference
deviation distribution \a\ distribution \a\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1................................. 133 m \b\........... 115 [micro]g/g \c\.. 4.03................ 12.................. 1,140 [micro]g/g \c\ Ishizaki et al. 1989.
2................................. 161 f \b\........... 146 [micro]g/g \c\.. 3.11................ 23.................. 940 [micro]g/g \c\.. Ishizaki et al. 1989.
[[Page 217]]
3................................. 10.................. 84 [micro]g/g....... .................... .................... .................... Ellis et al. 1983.
4................................. 203................. 76 [micro]g/l....... .................... .................... .................... Stewart and Hughes 1981.
5................................. 9................... 103 [micro]g/g...... .................... .................... .................... Chia et al. 1989.
6................................. 47 \d\.............. 86 [micro]g/L....... 1.9................. 30 [micro]g/1....... 250 [micro]g/L...... Kjellstrom et al. 1977.
7................................. 1,000 \e\........... 68.1 [micro]g/gr Cr 3.1 m & f........... < 10 [micro]g/gr Cr 320 [micro]g/gr Cr Kowal 1983.
\f\. \h\. \h\.
8................................. 87.................. 71 [micro]g/g \i\... .................... 7 \h\............... 200 \h\............. Buchet et al. 1980.
9................................. 10.................. 0.073 mg/24h........ .................... .................... .................... Evrin et al. 1971.
10................................ 59.................. 156 [micro]g/g...... 1.1 \j\............. 130................. 180................. Mason et al. 1988.
11................................ 8................... 118 [micro]g/g...... .................... .................... .................... Iwao et al. 1980.
12................................ 34.................. 79 [micro]g/g....... .................... .................... .................... Wibowo et al. 1982.
13................................ 41 m................ .................... .................... .................... 400 [micro]g/gr Cr Falck et al. 1983.
\k\.
14................................ 35 \n\.............. 67.................. .................... .................... .................... Roels et al. 1991.
15................................ 31 \d\.............. 63.................. .................... .................... .................... Roels et al. 1991.
16................................ 36 \d\.............. 77 \i\.............. .................... .................... .................... Miksche et al. 1981.
17................................ 18 \n\.............. 130................. .................... .................... .................... Kawada et al. 1989.
18................................ 32 \p\.............. 122................. .................... .................... .................... Kawada et al. 1989.
19................................ 18 \d\.............. 295................. 1.4................. 170................. 510................. Thun et al. 1989.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
a--Based on an assumed lognormal distribution.
b--m = males, f = females.
c--Aged general population from non-polluted area; 47.9% population aged 50-69; 52.1% = 70 years of age; values reported in study.
d--Exposed workers without proteinuria.
e--492 females, 484 male.
f--Creatinine adjusted; males = 68.1 [micro]g/g Cr, females = 64.3 [micro]g/g Cr.
h--Reported in the study.
i--Arithmetic mean.
j--Geometric standard error.
k--Upper 95% tolerance limits: for Falck this is based on the 24 hour urine sample.
n--Controls.
p--Exposed synthetic resin and pigment workers without proteinuria; Cadmium in urine levels up to 10 [micro]g/g Cr.
To the extent possible, the studies listed in Table 9 provide
geometric means and geometric standard deviations for measurements among
the groups defined in each study. For studies reporting a geometric
standard deviation along with a mean, the lower and upper 95th
percentile for these distributions were derived and reported in the
table.
The data provided from 15 of the 19 studies listed in Table 9
indicate that the geometric mean concentration of B2M observed among
those who were not occupationally exposed to cadmium is 70-170 [micro]g/
g CRTU. Data from the 4 remaining studies indicate that exposed workers
who exhibit no signs of proteinuria show mean B2MU levels of 60-300
[micro]g/g CRTU. B2MU values in the study by Thun et al. (1989),
however, appear high in comparison to the other 3 studies. If this study
is removed, B2MU levels for those who are not occupationally exposed to
cadmium are similar to B2MU levels found among cadmium-exposed workers
who exhibit no signs of kidney dysfunction. Although the mean is high in
the study by Thun et al., the range of measurements reported in this
study is within the ranges reported for the other studies.
Determining a reasonable upper limit from the range of B2M
concentrations observed among those who do not exhibit signs of
proteinuria is problematic. Elevated B2MU levels are among the signs
used to define the onset of kidney dysfunction. Without access to the
raw data from the studies listed in Table 9, it is necessary to rely on
reported standard deviations to estimate an upper limit for normal B2MU
concentrations (i.e., the upper 95th percentile for the distributions
measured). For the 8 studies reporting a geometric standard deviation,
the upper 95th percentiles for the distributions are 180-
[[Page 218]]
1140 [micro]g/g CRTU. These values are in general agreement with the
upper 95th percentile for the distribution (i.e., 631 [micro]g/g CRTU)
reported by Buchet et al. (1980). These upper limits also appear to be
in general agreement with B2MU values (i.e., 100-690 [micro]g/g CRTU)
reported as the normal upper limit by Iwao et al. (1980), Kawada et al.
(1989), Wibowo et al. (1982), and Schardun and van Epps (1987). These
values must be compared to levels reported among those exhibiting kidney
dysfunction to define a threshold level for kidney dysfunction related
to cadmium exposure.
5.3.7.2 Range of B2MU concentrations among exposed workers
Table 10 presents results from studies reporting B2MU determinations
among those occupationally exposed to cadmium in the work place; in some
of these studies, kidney dysfunction was observed among exposed workers,
while other studies did not make an effort to distinguish among exposed
workers based on kidney dysfunction. As with Table 9, this table
provides geometric means and geometric standard deviations for the
groups defined in each study if available. For studies reporting a
geometric standard deviation along with a mean, the lower and upper 95th
percentiles for the distributions are derived and reported in the table.
Table 10--B-2-Microglobulin Concentrations Observed in Urine Among Occupationally-Exposed workers
----------------------------------------------------------------------------------------------------------------
Concentration of B-2-Microglobulin in
urine
--------------------------------------------
Study No. N Geometric Reference
mean Geom std L 95% of U 95% of
([micro]g/ dev range \b\ range \b\
g) \a\
----------------------------------------------------------------------------------------------------------------
1................................. 1,42 160 6.19 8.1 3,300 Ishizaki et al., 1989.
4
2................................. 1,75 260 6.50 12 5,600 Ishizaki et al., 1989.
4
3................................. 33 210 ........ ......... ......... Ellis et al., 1983.
4................................. 65 210 ........ ......... ......... Chia et al., 1989.
5................................. \c\ 44 5,700 6.49 \d\ 300 \d\ Kjellstrom et al.,
98,000 1977.
6................................. 148 \e\ 180 ........ \f\ 110 \f\ 280 Buchet et al., 1980.
7................................. 37 160 3.90 17 1,500 Kenzaburo et al.,
1979.
8................................. \c\ 45 3,300 8.7 \d\ 310 \d\ Mason et al., 1988.
89,000
9................................. \c\ 10 6,100 5.99 \f\ 650 \f\ Falck et al., 1983.
57,000
10................................. \c\ 11 3,900 2.96 \d\ 710 \d\ Elinder et al., 1985.
15,000
11................................. \c\ 12 300 ........ ......... ......... Roels et al., 1991.
12................................. \g\ 8 7,400 ........ ......... ......... Roels et al., 1991.
13................................. \c\ 23 \h\ 1,800 ........ ......... ......... Roels et al., 1989.
14................................. 10 690 ........ ......... ......... Iwao et al., 1980.
15................................. 34 71 ........ ......... ......... Wibowo et al., 1982.
16................................. \c\ 15 4,700 6.49 \d\ 590 \d\ Thun et al., 1989.
93,000
----------------------------------------------------------------------------------------------------------------
\a\ Unless otherwise stated.
\b\ Based on an assumed lognormal distribution.
\c\ Among workers diagnosed as having renal dysfunction; for Elinder this means [beta] 2 levels greater than 300
micrograms per gram creatinine ([micro]g/gr Cr); for Roels, 1991, range = 31 - 35, 170 [micro]g[beta]2/gr Cr
and geometric mean = 63 among healthy workers; for Mason [beta]2 > 300 [micro]g/gr Cr.
\d\ Based on a detailed review of the data by OSHA.
\e\ Arthmetic mean.
\f\ Reported in the study.
\g\ Retired workers.
\h\ 1,800 [micro]g[beta]2/gr Cr for first survey; second survey = 1,600; third survey = 2,600; fourth survey =
2,600; fifth survey = 2,600.
The data provided in Table 10 indicate that the mean B2MU
concentration observed among workers experiencing occupational exposure
to cadmium (but with undefined levels of proteinuria) is 160-7400
[micro]g/g CRTU. One of these studies reports geometric means lower than
this range (i.e., as low as 71 [micro]g/g CRTU); an explanation for this
wide spread in average concentrations is not available.
Seven of the studies listed in Table 10 report a range of B2MU
levels among those diagnosed as having renal dysfunction. As indicated
in this table, renal dysfunction (proteinuria) is defined in several of
these studies by B2MU levels in excess of 300 [micro]g/g CRTU
[[Page 219]]
(see footnote ``c'' of Table 10); therefore, the range of B2MU levels
observed in these studies is a function of the operational definition
used to identify those with renal dysfunction. Nevertheless, a B2MU
level of 300 [micro]g/g CRTU appears to be a meaningful threshold for
identifying those having early signs of kidney damage. While levels much
higher than 300 [micro]g/g CRTU have been observed among those with
renal dysfunction, the vast majority of those not occupationally exposed
to cadmium exhibit much lower B2MU concentrations (see Table 9).
Similarly, the vast majority of workers not exhibiting renal dysfunction
are found to have levels below 300 [micro]g/g CRTU (Table 9).
The 300 [micro]g/g CRTU level for B2MU proposed in the above
paragraph has support among researchers as the threshold level that
distinguishes between cadmium-exposed workers with and without kidney
dysfunction. For example, in the guide for physicians who must evaluate
cadmium-exposed workers written for the Cadmium Council by Dr. Lauwerys,
levels of B2M greater than 200-300 [micro]g/g CRTU are considered to
require additional medical evaluation for kidney dysfunction (exhibit 8-
447, OSHA docket H057A). The most widely used test for measuring B2M
(i.e., the Pharmacia Delphia test) defines B2MU levels above 300
[micro]g/l as abnormal (exhibit L-140-1, OSHA docket H057A).
Dr. Elinder, chairman of the Department of Nephrology at the
Karolinska Institute, testified at the hearings on the proposed cadmium
rule. According to Dr. Elinder (exhibit L-140-45, OSHA docket H057A),
the normal concentration of B2MU has been well documented (Evrin and
Wibell 1972; Kjellstrom et al. 1977a; Elinder et al. 1978, 1983; Buchet
et al. 1980; Jawaid et al. 1983; Kowal and Zirkes, 1983). Elinder stated
that the upper 95 or 97.5 percentiles for B2MU among those without
tubular dysfunction is below 300 [micro]g/g CRTU (Kjellstrom et al.
1977a; Buchet et al. 1980; Kowal and Zirkes, 1983). Elinder defined
levels of B2M above 300 [micro]g/g CRTU as ``slight'' proteinuria.
5.3.8 Conclusions and Recommendations for B2MU
Based on the above evaluation, the following recommendations are
made for a B2MU proficiency testing program. Note that the following
discussion addresses only sampling and analysis for B2MU determinations
(i.e., to be reported as an unadjusted [micro]g B2M/l urine).
Normalizing this result to creatinine requires a second analysis for
CRTU (see Section 5.4) so that the ratio of the 2 measurements can be
obtained.
5.3.8.1 Recommended method
The Pharmacia Delphia method (Pharmacia 1990) should be adopted as
the standard method for B2MU determinations. Laboratories may adopt
alternate methods, but it is the responsibility of the laboratory to
demonstrate that alternate methods provide results of comparable quality
to the Pharmacia Delphia method.
5.3.8.2 Data quality objectives
The following data quality objectives should facilitate
interpretation of analytical results, and should be achievable based on
the above evaluation.
Limit of Detection. A limit of 100 [micro]g/l urine should be
achievable, although the insert to the test kit (Pharmacia 1990) cites a
detection limit of 150 [micro]g/l; private conversations with
representatives of Pharmacia, however, indicate that the lower limit of
100 [micro]g/l should be achievable provided an additional standard of
100 [micro]g/l B2M is run with the other standards to derive the
calibration curve (Section 3.3.1.1). The lower detection limit is
desirable due to the proximity of this detection limit to B2MU values
defined for the cadmium medical monitoring program.
Accuracy. Because results from an interlaboratory proficiency
testing program are not available currently, it is difficult to define
an achievable level of accuracy. Given the general performance
parameters defined by the insert to the test kits, however, an accuracy
of 15% of the target value appears achievable.
Due to the low levels of B2MU to be measured generally, it is
anticipated that the analysis of creatinine will contribute relatively
little to the overall variability observed among creatinine-normalized
B2MU levels (see Section 5.4). The initial level of accuracy for
reporting B2MU levels under this program should be set at 15%.
Precision. Based on precision data reported by Pharmacia (1990), a
precision value (i.e., CV) of 5% should be achievable over the defined
range of the analyte. For internal QC samples (i.e., recommended as part
of an internal QA/QC program, Section 3.3.1), laboratories should attain
precision near 5% over the range of concentrations measured.
5.3.8.3 Quality assurance/quality control
Commercial laboratories providing measurement of B2MU should adopt
an internal QA/QC program that incorporates the following components:
Strict adherence to the Pharmacia Delphia method, including calibration
requirements; regular use of QC samples during routine runs; a protocol
for corrective actions, and documentation of these actions; and,
participation in an interlaboratory proficiency program. Procedures that
may be used to address internal QC requirements are presented in
Attachment 1. Due to differences between analyses for B2MU and CDB/CDU,
specific values presented in Attachment 1 may have to be modified. Other
[[Page 220]]
components of the program (including characterization runs), however,
can be adapted to a program for B2MU.
5.4 Monitoring Creatinine in Urine (CRTU)
Because CDU and B2MU should be reported relative to concentrations
of CRTU, these concentrations should be determined in addition CDU and
B2MU determinations.
5.4.1 Units of CRTU Measurement
CDU should be reported as [micro]g Cd/g CRTU, while B2MU should be
reported as [micro]g B2M/g CRTU. To derive the ratio of cadmium or B2M
to creatinine, CRTU should be reported in units of g crtn/l of urine.
Depending on the analytical method, it may be necessary to convert
results of creatinine determinations accordingly.
5.4.2 Analytical Techniques Used To Monitor CRTU
Of the techniques available for CRTU determinations, an absorbance
spectrophotometric technique and a high-performance liquid
chromatography (HPLC) technique are identified as acceptable in this
protocol.
5.4.3 Methods Developed for CRTU Determinations
CRTU analysise performed in support of either CDU or B2MU
determinations should be performed using either of the following 2
methods:
1. The Du Pont method (i.e., Jaffe method), in which creatinine in a
sample reacts with picrate under alkaline conditions, and the resulting
red chromophore is monitored (at 510 nm) for a fixed interval to
determine the rate of the reaction; this reaction rate is proportional
to the concentration of creatinine present in the sample (a copy of this
method is provided in Attachment 2 of this protocol); or,
2. The OSHA SLC Technical Center (OSLTC) method, in which creatinine
in an aliquot of sample is separated using an HPLC column equipped with
a UV detector; the resulting peak is quantified using an electrical
integrator (a copy of this method is provided in Attachment 3 of this
protocol).
5.4.4 Sample Collection and Handling
CRTU samples should be segregated from samples collected for CDU or
B2MU analysis. Sample-collection techniques have been described under
Section 5.2.4. Samples should be preserved either to stabilize CDU (with
HNO3) or B2MU (with NaOH). Neither of these procedures should
adversely affect CRTU analysis (see Attachment 3).
5.4.5 General Method Performance
Data from the OSLTC indicate that a CV of 5% should be achievable
using the OSLTC method (Septon, L private communication). The achievable
accuracy of this method has not been determined.
Results reported in surveys conducted by the CAP (CAP 1991a, 1991b
and 1992) indicate that a CV of 5% is achievable. The accuracy
achievable for CRTU determinations has not been reported.
Laboratories performing creatinine analysis under this protocol
should be CAP accredited and should be active participants in the CAP
surveys.
5.4.6 Observed CRTU Concentrations
Published data suggest the range of CRTU concentrations is 1.0-1.6 g
in 24-hour urine samples (Harrison 1987). These values are equivalent to
about 1 g/l urine.
5.4.7 Conclusions and Recommendations for CRTU
5.4.7.1 Recommended method
Use either the Jaffe method (Attachment 2) or the OSLTC method
(Attachment 3). Alternate methods may be acceptable provided adequate
performance is demonstrated in the CAP program.
5.4.7.2 Data quality objectives
Limit of Detection. This value has not been formally defined;
however, a value of 0.1 g/l urine should be readily achievable.
Accuracy. This value has not been defined formally; accuracy should
be sufficient to retain accreditation from the CAP.
Precision. A CV of 5% should be achievable using the recommended
methods.
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Piscator M. (1962). Proteinuria in chronic cadmium poisoning.
Archives of Environmental Health,5, 55-62.
[[Page 223]]
Potts, C.L. (1965). Cadmium Proteinuria--The Health Battery Workers
Exposed to Cadmium Oxide dust. Ann Occup Hyg, 3:55-61, 1965.
Princi F. (1947). A study of industrial exposures to cadmium.
Journal of Industrial Hygiene and Toxicology, 29, 315-320.
Pruszkowska E, Carnick G, and Slavin W. (1983). Direct determination
of cadmium in urine with use of a stabilized temperature platform
furnace and Zeeman background correction. Clinical Chemistry, 29, 477-
480.
Roberts C and Clark J. (1986). Improved determination of cadmium in
blood and plasma by flameless atomic absorption spectroscopy. Bulletin
of Environmental Contamination and Toxicology, 36, 496-499.
Roelandts I. (1989). Biological reference materials. Soectrochimica
Acta, 44B, 281-290.
Roels H, Buchet R, Lauwerys R, Bruaux P, Clays-Thoreau F,
Laafontaine A, Overschelde J, and Verduyn J. (1978). Lead and cadmium
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Roels H, Djubgang J, Buchet J, Bernard A, and Lauwerys R. (1982).
Evolution of cadmium-induced renal dysfunction in workers removed from
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Attachment 1--Nonmandatory Protocol for an Internal Quality Assurance/
Quality Control Program
The following is an example of the type of internal quality
assurance/quality control program that assures adequate control to
satisfy OSHA requirements under this protocol. However, other approaches
may also be acceptable.
As indicated in Section 3.3.1 of the protocol, the QA/QC program for
CDB and CDU should address, at a minimum, the following:
calibration;
establishment of control limits;
internal QC analyses and maintaining control; and
corrective action protocols.
This illustrative program includes both initial characterization
runs to establish the performance of the method and ongoing analysis of
quality control samples intermixed with compliance samples to maintain
control.
Calibration
Before any analytical runs are conducted, the analytic instrument
must be calibrated. This is to be done at the beginning of each day on
which quality control samples and/or compliance samples are run. Once
calibration is established, quality control samples or compliance
samples may be run. Regardless of the type of samples run, every fifth
sample must be a standard to assure that the calibration is holding.
Calibration is defined as holding if every standard is within plus
or minus () 15% of its theoretical value. If a
standard is more than plus or minus 15% of its theoretical value, then
the run is out of control due to calibration error and the entire set of
samples must either be reanalyzed after recalibrating or results should
be recalculated based on a statistical curve derived from the
measurement of all standards.
It is essential that the highest standard run is higher than the
highest sample run. To assure that this is the case, it may be necessary
to run a high standard at the end of the run, which is selected based on
the results obtained over the course of the run.
All standards should be kept fresh, and as they get old, they should
be compared with new standards and replaced if they exceed the new
standards by 15%.
Initial Characterization Runs and Establishing Control
A participating laboratory should establish four pools of quality
control samples for each of the analytes for which determinations will
be made. The concentrations of quality control samples within each pool
are to be centered around each of the four target levels for the
particular analyte identified in Section 4.4 of the protocol.
Within each pool, at least 4 quality control samples need to be
established with varying concentrations ranging between plus or minus
50% of the target value of that pool. Thus for the medium-high cadmium
in blood pool, the theoretical values of the quality control samples may
range from 5 to 15 [micro]g/l, (the target value is 10 [micro]g/l). At
least 4 unique theoretical values must be represented in this pool.
The range of theoretical values of plus or minus 50% of the target
value of a pool means that there will be overlap of the pools. For
example, the range of values for the medium-low pool for cadmium in
blood is 3.5 to 10.5 [micro]g/l while the range of values for the
medium-high pool is 5 to 15 [micro]g/l. Therefore, it is possible for a
quality control sample from the medium-low pool to have a higher
concentration of cadmium than a quality control sample from the medium-
high pool.
Quality control samples may be obtained as commercially available
reference materials, internally prepared, or both. Internally prepared
samples should be well characterized and traced or compared to a
reference material for which a consensus value for concentration is
available. Levels of analyte in the quality control samples must be
concealed from the analyst prior to the reporting of analytical results.
Potential sources of materials that may be used to construct quality
control samples are listed in Section 3.3.1 of the protocol.
Before any compliance samples are analyzed, control limits must be
established. Control limits should be calculated for every pool of each
analyte for which determinations will be made and control charts should
be kept for each pool of each analyte. A separate set of control charts
and control limits should be established for each analytical instrument
in a laboratory that will be used for analysis of compliance samples.
At the beginning of this QA/QC program, control limits should be
based on the results of the analysis of 20 quality control samples from
each pool of each analyte. For any given pool, the 20 quality control
samples should be run on 20 different days. Although no more than one
sample should be run from
[[Page 225]]
any single pool on a particular day, a laboratory may run quality
control samples from different pools on the same day. This constitutes a
set of initial characterization runs.
For each quality control sample analyzed, the value F/T (defined in
the glossary) should be calculated. To calculate the control limits for
a pool of an analyte, it is first necessary to calculate the mean, X, of
the F/T values for each quality control sample in a pool and then to
calculate its standard deviation [sigma]. Thus, for the control limit
for a pool, X is calculated as:
[GRAPHIC] [TIFF OMITTED] TC15NO91.186
and [sigma] is calculated as
[GRAPHIC] [TIFF OMITTED] TC15NO91.187
Where N is the number of quality control samples run for a pool.
The control limit for a particular pool is then given by the mean
plus or minus 2 standard deviations (X 3[sigma]).
The control limits may be no greater than 40% of the mean F/T value.
If three standard deviations are greater than 40% of the mean F/T value,
then analysis of compliance samples may not begin. \1\ Instead, an
investigation into the causes of the large standard deviation should
begin, and the inadequacies must be remedied. Then, control limits must
be reestablished which will mean repeating the running 20 quality
control samples from each pool over 20 days.
---------------------------------------------------------------------------
\1\ Note that the value,``40%'' may change over time as experience
is gained with the program.
---------------------------------------------------------------------------
Internal Quality Control Analyses and Maintaining Control
Once control limits have been established for each pool of an
analyte, analysis of compliance samples may begin. During any run of
compliance samples, quality control samples are to be interspersed at a
rate of no less than 5% of the compliance sample workload. When quality
control samples are run, however, they should be run in sets consisting
of one quality control sample from each pool. Therefore, it may be
necessary, at times, to intersperse quality control samples at a rate
greater than 5%.
There should be at least one set of quality control samples run with
any analysis of compliance samples. At a minimum, for example, 4 quality
control samples should be run even if only 1 compliance sample is run.
Generally, the number of quality control samples that should be run are
a multiple of four with the minimum equal to the smallest multiple of
four that is greater than 5% of the total number of samples to be run.
For example, if 300 compliance samples of an analyte are run, then at
least 16 quality control samples should be run (16 is the smallest
multiple of four that is greater than 15, which is 5% of 300).
Control charts for each pool of an analyte (and for each instrument
in the laboratory to be used for analysis of compliance samples) should
be established by plotting F/T versus date as the quality control sample
results are reported. On the graph there should be lines representing
the control limits for the pool, the mean F/T limits for the pool, and
the theoretical F/T of 1.000. Lines representing plus or minus () [sigma] should also be represented on the charts. A
theoretical example of a control chart is presented in Figure 1.
Figure 1--Theoretical Example of a Control Chart for a Pool of an Analyte
..... ..... ..... ..... ..... ..... ..... ..... ..... ..... ..... 1.162 (Upper
Control Limit)
..... ..... ..... ..... ..... X
..... ..... ..... ..... ..... ..... ..... ..... ..... ..... ..... 1.096 (Upper
2[sigma] Line)
..... X
X ..... ..... ..... ..... ..... ..... ..... ..... ..... ..... 1.000 (Theoretical
Mean)
..... ..... ..... X X ..... ..... ..... ..... ..... ..... 0.964 (Mean)
..... ..... ..... ..... ..... ..... X ..... ..... ..... X
..... ..... ..... ..... ..... ..... ..... X
..... ..... X ..... ..... ..... ..... ..... ..... ..... ..... 0.832 (Lower
2[sigma] Line)
..... ..... ..... ..... ..... ..... ..... ..... X
..... ..... ..... ..... ..... ..... ..... ..... ..... ..... ..... 0.766 (Lower
Control Limit)
March 2 2 3 5 6 9 10 13 16 17
----------------------------------------------------------------------------------------------------------------
[[Page 226]]
All quality control samples should be plotted on the chart, and the
charts should be checked for visual trends. If a quality control sample
falls above or below the control limits for its pool, then corrective
steps must be taken (see the section on corrective actions below). Once
a laboratory's program has been established, control limits should be
updated every 2 months.
The updated control limits should be calculated from the results of
the last 100 quality control samples run for each pool. If 100 quality
control samples from a pool have not been run at the time of the update,
then the limits should be based on as many as have been run provided at
least 20 quality control samples from each pool have been run over 20
different days.
The trends that should be looked for on the control charts are:
1. 10 consecutive quality control samples falling above or below the
mean;
2. 3 consecutive quality control samples falling more than 2[sigma]
from the mean (above or below the 2[sigma] lines of the chart); or
3. the mean calculated to update the control limits falls more than
10% above or below the theoretical mean of 1.000.
If any of these trends is observed, then all analysis must be
stopped, and an investigation into the causes of the errors must begin.
Before the analysis of compliance samples may resume, the inadequacies
must be remedied and the control limits must be reestablished for that
pool of an analyte. Reestablishment of control limits will entail
running 20 sets of quality control samples over 20 days.
Note that alternative procedures for defining internal quality
control limits may also be acceptable. Limits may be based, for example,
on proficiency testing, such as 1 [micro]g or 15%
of the mean (whichever is greater). These should be clearly defined.
Corrective actions
Corrective action is the term used to describe the identification
and remediation of errors occurring within an analysis. Corrective
action is necessary whenever the result of the analysis of any quality
control sample falls outside of the established control limits. The
steps involved may include simple things like checking calculations of
basic instrument maintenance, or it may involve more complicated actions
like major instrument repair. Whatever the source of error, it must be
identified and corrected (and a Corrective Action Report (CAR) must be
completed. CARs should be kept on file by the laboratory.
Attachment 2--Creatinine in Urine (Jaffe Procedure)
Intended use: The CREA pack is used in the Du Pont ACA [supreg]
discrete clinical analyzer to quantitatively measure creatinine in serum
and urine.
Summary: The CREA method employs a modification of the kinetic Jaffe
reaction reported by Larsen. This method has been reported to be less
susceptible than conventional methods to interference from non-
creatinine, Jaffe-positive compounds. \1\
A split sample comparison between the CREA method and a conventional
Jaffe procedure on Autoanalyzer [supreg] showed a good correlation. (See
Specific Performance Characteristics).
*Note: Numbered subscripts refer to the bibliography and lettered
subscripts refer to footnotes.
Autoanalyzer [supreg], is a registered trademark of Technicon Corp.,
Tarrytown, NY.
Principles of Procedure: In the presence of a strong base such as
NaOH, picrate reacts with creatinine to form a red chromophore. The rate
of increasing absorbance at 510 nm due to the formation of this
chromophore during a 17.07-second measurement period is directly
proportional to the creatinine concentration in the sample.
[GRAPHIC] [TIFF OMITTED] TC15NO91.188
Reagents:
----------------------------------------------------------------------------------------------------------------
Compartment \a\ Form Ingredient Quantity \b\
----------------------------------------------------------------------------------------------------------------
No. 2, 3, & 4........................ Liquid................. Picrate................ 0.11 mmol.
6.................................... Liquid................. NaOH (for pH
adjustment) \c\.
----------------------------------------------------------------------------------------------------------------
a. Compartments are numbered 1-7, with compartment 7 located closest to pack fill position 2.
b. Nominal value at manufacture.
c. See Precautions.
[[Page 227]]
Precautions: Compartment 6 contains 75[micro]L of 10 N
NaOH; avoid contact; skin irritant; rinse contacted area with water.
Comply with OSHA'S Bloodborne Pathogens Standard while handling
biological samples (29 CFR 1910.1039).
Used packs contain human body fluids; handle with appropriate care.
FOR IN VITRO DIAGNOSTIC USE
Mixing and Diluting:
Mixing and diluting are automatically performed by the ACA [supreg]
discrete clinical analyzer. The sample cup must contain sufficient
quantity to accommodate the sample volume plus the ``dead volume'';
precise cup filling is not required.
Sample Cup Volumes ([micro]L)
----------------------------------------------------------------------------------------------------------------
Standard Microsystem
Analyzer ---------------------------------------------------
Dead Total Dead Total
----------------------------------------------------------------------------------------------------------------
II, III..................................................... 120 3000 10 500
IV, SX...................................................... 120 3000 30 500
V........................................................... 90 3000 10 500
----------------------------------------------------------------------------------------------------------------
Storage of Unprocessed Packs: Store at 2-8 [deg]C. Do not freeze. Do
not expose to temperatures above 35 [deg]C or to direct sunlight.
Expiration: Refer to EXPIRATION DATE on the tray label.
Specimen Collection: Serum or urine can be collected and stored by
normal procedures. \2\
Known Interfering Substances \3\
Serum Protein Influence--Serum protein levels
exert a direct influence on the CREA assay. The following should be
taken into account when this method is used for urine samples and when
it is calibrated:
Aqueous creatinine standards or urine specimens will give CREA
results depressed by approximately 0.7 mg/dL [62 [micro]mol/L] \d\ and
will be less precise than samples containing more than 3 g/dL [30 g/L]
protein.
All urine specimens should be diluted with an albumin solution to
give a final protein concentration of at least 3 g/dL [30 g/L]. Du Pont
Enzyme Diluent (Cat. 790035-901) may be used for this purpose.
High concentration of endrogenous bilirubin
(20 mg/dL [342 [micro]mol/L]) will give depressed
CREA results (average depression 0.8 mg/dL [71 [micro]mol/L]). \4\
Grossly hemolyzed (hemoglobin 100 mg/
dL [62 [micro]mol/L]) or visibly lipemic specimens may cause
falsely elevated CREA results. \5,6\
The following cephalosporin antibiotics do not
interfere with the CREA method when present at the concentrations
indicated. Systematic inaccuracies (bias) due to these substances are
less than or equal to 0.1 mg/dL [8.84 [micro]mol/L] at CREA
concentrations of approximately 1 mg/dL [88 [micro]mol/L].
----------------------------------------------------------------------------------------------------------------
Peak serum level Drug concentration
\7,8,9\ ---------------------
Antibiotic ------------------------
mg/dL [mmol/L] mg/dL [mmol/L]
----------------------------------------------------------------------------------------------------------------
Cephaloridine..................................................... 1.4 0.3 25 6.0
Cephalexin........................................................ 0.6-2.0 0.2-0.6 25 7.2
Cephamandole...................................................... 1.3-2.5 0.3-0.5 25 4.9
Cephapirin........................................................ 2.0 D0.4 25 5.6
Cephradine........................................................ 1.5-2.0 0.4-0.6 25 7.1
Cefazolin......................................................... 2.5-5.0 0.55-1.1 50 11.0
----------------------------------------------------------------------------------------------------------------
The following cephalosporin antibiotics have been
shown to affect CREA results when present at the indicated
concentrations. System inaccuracies (bias) due to these substances are
greater that 0.1 mg/dL [8.84 [micro]mol/L] at CREA concentrations of:
----------------------------------------------------------------------------------------------------------------
Peak serum level Drug concentration
\8,10\ --------------------------------
Antibiotic ------------------------
mg/dL [mmol/L] mg/dL [mmol/L] Effect
----------------------------------------------------------------------------------------------------------------
Cephalothin............................................ 1-6 0.2-1.5 100 25.2 [darr]20-
25%
Cephoxitin............................................. 2.0 0.5 5.0 1.2 [uarr]35-
40%
----------------------------------------------------------------------------------------------------------------
[[Page 228]]
The single wavelength measurement used in this
method eliminates interference from chromophores whose 510 nm absorbance
is constant throughout the measurement period.
Each laboratory should determine the
acceptability of its own blood collection tubes and serum separation
products. Variations in these products may exist between manufacturers
and, at times, from lot to lot.
d. Systeme International d'unites (S.I. Units) are in brackets.
Procedure:
Test Materials
----------------------------------------------------------------------------------------------------------------
II, III Du IV, SX Du Pont V Du Pont Cat.
Item Pont Cat. No. Cat. No. No.
----------------------------------------------------------------------------------------------------------------
ACA [supreg] CREA Analytical Test Pack.......................... 701976901 701976901 701976901
Sample System Kit or............................................ 710642901 710642901 713697901
Micro Sample System Kit and..................................... 702694901 710356901 NA
Micro Sample System Holders..................................... 702785000 NA NA
DYLUX [supreg] Photosensitive...................................
Printer Paper................................................... 700036000 NA NA
Thermal Printer Paper........................................... NA 710639901 713645901
Du Pont Purified Water.......................................... 704209901 710615901 710815901
Cell Wash Solution.............................................. 701864901 710664901 710864901
----------------------------------------------------------------------------------------------------------------
Test Steps: The operator need only load the sample kit and
appropriate test pack(s) into a properly prepared ACA [supreg] discrete
clinical analyzer. It automatically advances the pack(s) through the
test steps and prints a result(s). See the Instrument Manual of the ACA
[supreg] analyzer for details of mechanical travel of the test pack(s).
Preset Creatinine (CREA)--Test Conditions
Sample Volume: 200 [micro]L
Diluent: Purified Water
Temperature: 37.0 0.1 [deg]C
Reaction Period: 29 seconds
Type of Measurement: Rate
Measurement Period: 17.07 seconds
Wavelength: 510 nm
Units: mg/dL [[micro]mol/L]
CALIBRATION: The general calibration procedure is described in the
Calibration/Verification chapter of the Manuals.
The following information should be considered when calibrating the
CREA method.
Assay Range: 0-20 mg/mL [0-1768 [micro]mol/L] \e\.
Reference Material: Protein containing primary
standards \f\ or secondary calibrators such as Du Pont Elevated
Chemistry Control (Cat. 790035903) and Normal Chemistry Control
(Cat.790035905) \g\.
Suggested Calibration Levels: 1,5,20, mg/mL [88, 442,
1768 [micro]mol/L].
Calibration Scheme: 3 levels, 3 packs per level.
Frequency: Each new pack lot. Every 3 months for any
one pack lot.
e. For the results in S.I. units [[micro]mol/L] the conversion
factory is 88.4.
f. Refer to the Creatinine Standard Preparation and Calibration
Procedure available on request from a Du Pont Representative.
g. If the Du Pont Chemistry Controls are being used, prepare them
according to the instructions on the product insert sheets.
Preset Creatinine (CREA) Test Conditions
------------------------------------------------------------------------
ACA [supreg] II ACA [supreg] III,
Item analyzer IV, SX, V analyzer
------------------------------------------------------------------------
Count by........................ One (1)........... NA
[Five (5)]........
Decimal Point................... 0.0 mg/dL......... 000.0 mg/dL
Location........................ [000.0 [micro]mol/ [000 [micro]mol/L]
L].
Assigned Starting............... 999.8............. -1.000 E1
Point or Offset Co.............. [9823.]........... [-8.840 E2]
Scale Factor or Assigned........ 0.2000............ 2.004 E-1 \h\
mg/dL/count \h\...
Linear Term C1 h................ [0.3536 [micro]mol/ [1.772E1]
L/count].
------------------------------------------------------------------------
h. The preset scale factor (linear term) was derived from the molar
absorptivity of the indicator and is based on an absorbance to activity
relationship (sensitivity) of 0.596 (mA/min)/(U/L). Due to small
differences in filters and electronic components between instruments,
the actual scale factor (linear
[[Page 229]]
term) may differ slightly from that given above.
Quality Control: Two types of quality control procedures are
recommended:
General Instrument Check. Refer to the Filter
Balance Procedure and the Absorbance Test Method described in the ACA
Analyzer Instrument Manual. Refer also to the ABS Test Methodology
literature.
Creatinine Method Check. At least once daily run
a CREA test on a solution of known creatinine activity such as an
assayed control or calibration standard other than that used to
calibrate the CREA method. For further details review the Quality
Assurance Section of the Chemistry Manual. The result obtained should
fall within acceptable limits defined by the day-to-day variability of
the system as measured in the user's laboratory. (See SPECIFIC
PERFORMANCE CHARACTERISTICS for guidance.) If the result falls outside
the laboratory's acceptable limits, follow the procedure outlined in the
Chemistry Troubleshooting Section of the Chemistry Manual.
A possible system malfunction is indicated when analysis of a sample
with five consecutive test packs gives the following results:
------------------------------------------------------------------------
Level SD
------------------------------------------------------------------------
1 mg/dL.................................. 0.15 mg/dL
[88 [micro]mol/L]........................ [13 [micro]mol/L]
20 mg/dL................................. 0.68 mg/dL
[1768 [micro]mol/L]...................... [60 [micro]mol/L]
------------------------------------------------------------------------
Refer to the procedure outlined in the Trouble Shooting Section of
the Manual.
Results: The ACA [supreg] analyzer automatically calculates and
prints the CREA result in mg/dL [[micro]mol/L].
Limitation of Procedure: Results 20 mg/dL [1768 [micro]mol/
L]:
Dilute with suitable protein base diluent.
Reassay. Correct for diluting before reporting.
The reporting system contains error messages to warn the operator of
specific malfunctions. Any report slip containing a letter code or word
immediately following the numerical value should not be reported. Refer
to the Manual for the definition of error codes.
Reference Interval
Serum: \11,i\
Males 0.8-1.3 md/dL
[71-115 [micro]mol/L]
Females 0.6-1.0 md/dL
[53-88 [micro]mol/L]
Urine: \12\
Males 0.6-2.5 g/24 hr
[53-221 mmol/24 hr]
Females 0.6-1.5 g/24 hr
[53-133 mmol/24 hr]
i. Reference interval data obtained from 200 apparently healthy
individuals (71 males, 129 females) between the ages of 19 and 72.
Each laboratory should establish its own reference intervals for
CREA as performed on the analyzer.
Specific Performance Characteristics \j\
Reproducibility \k\
----------------------------------------------------------------------------------------------------------------
Standard deviation (% CV)
Material Mean -------------------------------------------------
Within-run Between-day
----------------------------------------------------------------------------------------------------------------
Lyophilized.......................... 1.3.................... 0.05 (3.7)............. 0.05 (3.7)
Control.............................. [115].................. [4.4].................. [4.4]
Lyophilized.......................... 20.6................... 0.12 (0.6)............. 0.37 (1.8)
Control.............................. [1821]................. [10.6]................. [32.7]
----------------------------------------------------------------------------------------------------------------
Correlation--Regression Statistics \l\
----------------------------------------------------------------------------------------------------------------
Correlation
Comparative method Slope Intercept coefficient n
----------------------------------------------------------------------------------------------------------------
Autoanalyzer [supreg]............................................ 1.03 0.03[2.7] 0.997 260
----------------------------------------------------------------------------------------------------------------
j. All specific performance characteristics tests were run after
normal recommended equipment quality control checks were performed (see
Instrument Manual).
k. Specimens at each level were analyzed in duplicate for twenty
days. The within-run and between-day standard deviations were calculated
by the analysis of variance method.
l. Model equation for regression statistics is:
[[Page 230]]
[GRAPHIC] [TIFF OMITTED] TC15NO91.189
Assay Range \m\
0.0-20.0 mg/dl
[0-1768 [micro]mol]
m. See REPRODUCIBILITY for method performance within the assay
range.
Analytical Specificity
See KNOWN INTERFERING SUBSTANCES section for details.
Bibliography
\1\ Larsen, K, Clin Chem Acta 41, 209 (1972).
\2\ Tietz, NW, Fundamentals of Clinical Chemistry, W. B. Saunders
Co., Philadelphia, PA, 1976, pp 47-52, 1211.
\3\ Supplementary information pertaining to the effects of various
drugs and patient conditions on in vivo or in vitro diagnostic levels
can be found in ``Drug Interferences with Clinical Laboratory Tests,''
Clin. Chem 21 (5) (1975), and ``Effects of Disease on Clinical
Laboratory Tests,'' Clin Chem, 26 (4) 1D-476D (1980).
\4\ Watkins, R. Fieldkamp, SC, Thibert, RJ, and Zak, B, Clin Chem,
21, 1002 (1975).
\5\ Kawas, EE, Richards, AH, and Bigger, R, An Evaluation of a
Kinetic Creatinine Test for the Du Pont ACA, Du Pont Company,
Wilmington, DE (February 1973). (Reprints available from DuPont Company,
Diagnostic Systems)
\6\ Westgard, JO, Effects of Hemolysis and Lipemia on ACA Creatinine
Method, 0.200 [micro]L, Sample Size, Du Pont Company, Wilmington, DE
(October 1972).
\7\ Physicians' Desk Reference, Medical Economics Company, 33
Edition, 1979.
\8\ Henry, JB, Clinical Diagnosis and Management by Laboratory
Methods, W.B. Saunders Co., Philadelphia, PA 1979, Vol. III.
\9\ Krupp, MA, Tierney, LM Jr., Jawetz, E, Roe, RI, Camargo, CA,
Physicians Handbook, Lange Medical Publications, Los Altos, CA, 1982 pp
635-636.
\10\ Sarah, AJ, Koch, TR, Drusano, GL, Celoxitin Falsely Elevates
Creatinine Levels, JAMA 247, 205-206 (1982).
\11\ Gadsden, RH, and Phelps, CA, A Normal Range Study of Amylase in
Urine and Serum on the Du Pont ACA, Du Pont Company, Wilmington, DE
(March 1978). (Reprints available from DuPont Company, Diagnostic
Systems)
\12\ Dicht, JJ, Reference Intervals for Serum Amylase and Urinary
Creatinine on the Du Pont ACA [supreg] Discrete Clinical Analyzer, Du
Pont Company, Wilmington, DE (November 1984).
Attachment 3--Analysis of Creatinine for the Normalization of Cadmium
and Beta-2-Microglobulin Concentrations in Urine (OSLTC Procedure).
Matrix: Urine.
Target concentration: 1.1 g/L (this amount is representative of
creatinine concentrations found in urine).
Procedure: A 1.0 mL aliquot of urine is passed through a C18 SEP-PAK
[supreg] (Waters Associates). Approximately 30 mL of HPLC (high
performance liquid chromatography) grade water is then run through the
SEP-PAK. The resulting solution is diluted to volume in a 100-mL
volumetric flask and analyzed by HPLC using an ultraviolet (UV)
detector.
Special requirements: After collection, samples should be
appropriately stabilized for cadmium (Cd) analysis by using 10% high
purity (with low Cd background levels) nitric acid (exactly 1.0 mL of
10% nitric acid per 10 mL of urine) or stabilized for Beta-2-
Microglobulin (B2M) by taking to pH 7 with dilute NaOH (exactly 1.0 mL
of 0.11 N NaOH per 10 mL of urine). If not immediately analyzed, the
samples should be frozen and shipped by overnight mail in an insulated
container.
Dated: January 1992.
David B. Armitage,
Duane Lee,
Chemists.
Organic Service Branch II, OSHA Technical Center, Salt Lake City, Utah
1. General Discussion
1.1 Background
1.1.1. History of procedure
Creatinine has been analyzed by several methods in the past. The
earliest methods were of the wet chemical type. As an example,
creatinine reacts with sodium picrate in basic solution to form a red
complex, which is then analyzed colorimetrically (Refs. 5.1. and 5.2.).
Since industrial hygiene laboratories will be analyzing for Cd and
B2M in urine, they will be normalizing those concentrations to the
concentration of creatinine in urine. A literature search revealed
several HPLC methods (Refs. 5.3., 5.4., 5.5. and 5.6.) for creatinine in
urine and because many industrial hygiene laboratories have HPLC
equipment, it was desirable to develop an industrial hygiene HPLC method
for creatinine in urine. The method of Hausen, Fuchs, and Wachter was
chosen as the starting point for method development. SEP-PAKs were used
for sample clarification and cleanup
[[Page 231]]
in this method to protect the analytical column. The urine aliquot which
has been passed through the SEP-PAK is then analyzed by reverse-phase
HPLC using ion-pair techniques.
This method is very similar to that of Ogata and Taguchi (Ref.
5.6.), except they used centrifugation for sample clean-up. It is also
of note that they did a comparison of their HPLC results to those of the
Jaffe method (a picric acid method commonly used in the health care
industry) and found a linear relationship of close to 1:1. This
indicates that either HPLC or colorimetric methods may be used to
measure creatinine concentrations in urine.
1.1.2. Physical properties (Ref. 5.7.)
Molecular weight: 113.12
Molecular formula: C4-H7-N3-0
Chemical name: 2-amino-1,5-dihydro-1-methyl-4H-imidazol-4-one
CAS No.: 60-27-5
Melting point: 300 [deg]C (decomposes)
Appearance: white powder
Solubility: soluble in water; slightly soluble in alcohol; practically
insoluble in acetone, ether, and chloroform
Synonyms: 1-methylglycocyamidine, 1-methylhydantoin-2-imide
Structure: see Figure 1
[GRAPHIC] [TIFF OMITTED] TC28OC91.015
1.2. Advantages
1.2.1. This method offers a simple, straightforward, and specific
alternative method to the Jaffe method.
1.2.2. HPLC instrumentation is commonly found in many industrial
hygiene laboratories.
2. Sample stabilization procedure
2.1. Apparatus
Metal-free plastic container for urine sample.
2.2. Reagents
2.2.1. Stabilizing Solution--
(1) Nitric acid (10%, high purity with low Cd background levels) for
stabilizing urine for Cd analysis or
(2) NaOH, 0.11 N, for stabilizing urine for B2M analysis.
2.2.2. HPLC grade water
2.3. Technique
2.3.1. Stabilizing solution is added to the urine sample (see
section 2.2.1.). The stabilizing solution should be such that for each
10 mL of urine, add exactly 1.0 mL of stabilizer solution. (Never add
water or urine to acid or base. Always add acid or base to water or
urine.) Exactly 1.0 mL of 0.11 N NaOH added to 10 mL of urine should
result in a pH of 7. Or add 1.0 mL of 10% nitric acid to 10 mL of urine.
2.3.2. After sample collection seal the plastic bottle securely and
wrap it with an appropriate seal. Urine samples should be frozen and
then shipped by overnight mail (if shipping is necessary) in an
insulated container. (Do not fill plastic bottle too full. This will
allow for expansion of contents during the freezing process.)
2.4. The Effect of Preparation and Stabilization Techniques on
Creatinine Concentrations
Three urine samples were prepared by making one sample acidic, not
treating a second sample, and adjusting a third sample to pH 7. The
samples were analyzed in duplicate by two different procedures. For the
first procedure a 1.0 mL aliquot of urine was put in a 100-mL volumetric
flask, diluted to volume with HPLC grade water, and then analyzed
directly on an HPLC. The other procedure used SEP-PAKs. The SEP-PAK was
rinsed with approximately 5 mL of methanol followed by approximately 10
mL of HPLC grade water and both rinses were discarded. Then, 1.0 mL of
the urine sample was put through the SEP-PAK, followed by 30 mL of HPLC
grade water. The urine and water were transferred to a 100-mL volumetric
flask, diluted to volume with HPLC grade water, and analyzed by HPLC.
These three urine samples were analyzed on the day they were obtained
and then frozen. The results show that whether the urine is acidic,
untreated or adjusted to pH 7, the resulting answer for creatinine is
essentially unchanged. The purpose of stabilizing the urine by making it
acidic or neutral is for the analysis of Cd or B2M respectively.
[[Page 232]]
Comparison of Preparation & Stabilization Techniques
------------------------------------------------------------------------
w/o SEP- with SEP-
Sample PAK g/L PAK g/L
creatinine creatinine
------------------------------------------------------------------------
Acid............................................ 1.10 1.10
Acid............................................ 1.11 1.10
Untreated....................................... 1.12 1.11
Untreated....................................... 1.11 1.12
pH 7............................................ 1.08 1.02
pH 7............................................ 1.11 1.08
------------------------------------------------------------------------
2.5. Storage
After 4 days and 54 days of storage in a freezer, the samples were
thawed, brought to room temperature and analyzed using the same
procedures as in section 2.4. The results of several days of storage
show that the resulting answer of creatinine is essentially unchanged.
Storage Data
----------------------------------------------------------------------------------------------------------------
4 days 54 days
---------------------------------------------------
Sample w/o SEP-PAK with SEP- w/o SEP-PAK with SEP-
g/L PAK g/L g/L PAK g/L
creatinine creatinine creatinine creatinine
----------------------------------------------------------------------------------------------------------------
Acid........................................................ 1.09 1.09 1.08 1.09
Acid........................................................ 1.10 1.10 1.09 1.10
Acid........................................................ ........... ........... 1.09 1.09
Untreated................................................... 1.13 1.14 1.09 1.11
Untreated................................................... 1.15 1.14 1.10 1.10
Untreated................................................... ........... ........... 1.09 1.10
pH 7........................................................ 1.14 1.13 1.12 1.12
pH 7........................................................ 1.14 1.13 1.12 1.12
pH 7........................................................ ........... ........... 1.12 1.12
----------------------------------------------------------------------------------------------------------------
2.6. Interferences
None.
2.7. Safety precautions
2.7.1. Make sure samples are properly sealed and frozen before
shipment to avoid leakage.
2.7.2. Follow the appropriate shipping procedures.
The following modified special safety precautions are based on those
recommended by the Centers for Disease Control (CDC) (Ref. 5.8.). and
OSHA's Bloodborne Pathogens standard (29 CFR 1910.1039).
2.7.3. Wear gloves, lab coat, and safety glasses while handling all
human urine products. Disposable plastic, glass, and paper (pipet tips,
gloves, etc.) that contact urine should be placed in a biohazard
autoclave bag. These bags should be kept in appropriate containers until
sealed and autoclaved. Wipe down all work surfaces with 10% sodium
hypochlorite solution when work is finished.
2.7.4. Dispose of all biological samples and diluted specimens in a
biohazard autoclave bag at the end of the analytical run.
2.7.5. Special care should be taken when handling and dispensing
nitric acid. Always remember to add acid to water (or urine). Nitric
acid is a corrosive chemical capable of severe eye and skin damage. Wear
metal-free gloves, a lab coat, and safety glasses. If the nitric acid
comes in contact with any part of the body, quickly wash with copious
quantities of water for at least 15 minutes.
2.7.6. Special care should be taken when handling and dispensing
NaOH. Always remember to add base to water (or urine). NaOH can cause
severe eye and skin damage. Always wear the appropriate gloves, a lab
coat, and safety glasses. If the NaOH comes in contact with any part of
the body, quickly wash with copious quantities of water for at least 15
minutes.
3. Analytical procedure
3.1. Apparatus
3.1.1. A high performance liquid chromatograph equipped with pump,
sample injector and UV detector.
3.1.2. A C18 HPLC column; 25 cm x 4.6 mm I.D.
3.1.3. An electronic integrator, or some other suitable means of
determining analyte response.
3.1.4. Stripchart recorder.
3.1.5. C18 SEP-PAKs (Waters Associates) or equivalent.
3.1.6. Luer-lock syringe for sample preparation (5 mL or 10 mL).
3.1.7. Volumetric pipettes and flasks for standard and sample
preparation.
[[Page 233]]
3.1.8. Vacuum system to aid sample preparation (optional).
3.2. Reagents
3.2.1. Water, HPLC grade.
3.2.2. Methanol, HPLC grade.
3.2.3. PIC B-7 [supreg] (Waters Associates) in small vials.
3.2.4. Creatinine, anhydrous, Sigma hemical Corp., purity not
listed.
3.2.5. 1-Heptanesulfonic acid, sodium salt monohydrate.
3.2.6. Phosphoric acid.
3.2.7. Mobile phase. It can be prepared by mixing one vial of PIC B-
7 into a 1 L solution of 50% methanol and 50% water. The mobile phase
can also be made by preparing a solution that is 50% methanol and 50%
water with 0.005M heptanesulfonic acid and adjusting the pH of the
solution to 3.5 with phosphoric acid.
3.3. Standard preparation
3.3.1. Stock standards are prepared by weighing 10 to 15 mg of
creatinine. This is transferred to a 25-mL volumetric flask and diluted
to volume with HPLC grade water.
3.3.2. Dilutions to a working range of 3 to 35 [micro]g/mL are made
in either HPLC grade water or HPLC mobile phase (standards give the same
detector response in either solution).
3.4. Sample preparation
3.4.1. The C18 SEP-PAK is connected to a Luer-lock syringe. It is
rinsed with 5 mL HPLC grade methanol and then 10 mL of HPLC grade water.
These rinses are discarded.
3.4.2. Exactly 1.0 mL of urine is pipetted into the syringe. The
urine is put through the SEP-PAK into a suitable container using a
vacuum system.
3.4.3. The walls of the syringe are rinsed in several stages with a
total of approximately 30 mL of HPLC grade water. These rinses are put
through the SEP-PAK into the same container. The resulting solution is
transferred to a 100-mL volumetric flask and then brought to volume with
HPLC grade water.
3.5. Analysis (conditions and hardware are those used in this
evaluation.)
3.5.1. Instrument conditions
Column: Zorbax [supreg] ODS, 5-6 [micro]m particle size; 25 cm x 4.6
mm I.D.
Mobile phase: See Section 3.2.7.
Detector: Dual wavelength UV; 229 nm (primary) 254 nm (secondary)
Flow rate: 0.7 mL/ minute
Retention time: 7.2 minutes
Sensitivity: 0.05 AUFS
Injection volume: 20[micro]l
3.5.2. Chromatogram (see Figure 2)
[[Page 234]]
[GRAPHIC] [TIFF OMITTED] TC28OC91.016
3.6. Interferences
3.6.1. Any compound that has the same retention time as creatinine
and absorbs at 229 nm is an interference.
3.6.2. HPLC conditions may be varied to circumvent interferences. In
addition, analysis at another UV wavelength (i.e. 254 nm) would allow a
comparison of the ratio of response of a standard to that of a sample.
Any deviations would indicate an interference.
3.7. Calculations
[[Page 235]]
3.7.1. A calibration curve is constructed by plotting detector
response versus standard concentration (See Figure 3).
3.7.2. The concentration of creatinine in a sample is determined by
finding the concentration corresponding to its detector response. (See
Figure 3).
[GRAPHIC] [TIFF OMITTED] TC28OC91.017
[[Page 236]]
3.7.3. The [micro]g/mL creatinine from section 3.7.2. is then
multiplied by 100 (the dilution factor). This value is equivalent to the
micrograms of creatinine in the 1.0 mL stabilized urine aliquot or the
milligrams of creatinine per liter of urine. The desired units, g/L, is
determined by the following relationship:
[GRAPHIC] [TIFF OMITTED] TC15NO91.190
3.7.4. The resulting value for creatinine is used to normalize the
urinary concentration of the desired analyte (A) (Cd or B2M) by using
the following formula.
[GRAPHIC] [TIFF OMITTED] TC15NO91.191
Where A is the desired analyte. The protocol of reporting such
normalized results is [micro]g A/g creatinine.
3.8. Safety precautions See section 2.7.
4. Conclusions
The determination of creatinine in urine by HPLC is a good
alternative to the Jaffe method for industrial hygiene laboratories.
Sample clarification with SEP-PAKs did not change the amount of
creatinine found in urine samples. However, it does protect the
analytical column. The results of this creatinine in urine procedure are
unaffected by the pH of the urine sample under the conditions tested by
this procedure. Therefore, no special measures are required for
creatinine analysis whether the urine sample has been stabilized with
10% nitric acid for the Cd analysis or brought to a pH of 7 with 0.11 N
NaOH for the B2M analysis.
5. References
5.1. Clark, L.C.; Thompson, H.L.; Anal. Chem. 1949, 21, 1218.
5.2. Peters, J.H.; J. Biol. Chem. 1942, 146, 176.
5.3. Hausen, V.A.; Fuchs, D.; Wachter, H.; J. Clin. Chem. Clin. Biochem.
1981, 19, 373-378.
5.4. Clark, P.M.S.; Kricka L.J.; Patel, A.; J. Liq. Chrom. 1980, 3(7),
1031-1046.
5.5. Ballerini, R.; Chinol, M.; Cambi, A.; J. Chrom. 1979, 179, 365-369.
5.6. Ogata, M.; Taguchi, T.; Industrial Health 1987, 25, 225-228.
5.7. ``Merck Index'', 11th ed.; Windholz, Martha Ed.; Merck: Rahway,
N.J., 1989; p 403.
5.8. Kimberly, M.; ``Determination of Cadmium in Urine by Graphite
Furnace Atomic Absorption Spectrometry with Zeeman Background
Correction.'', Centers for Disease Control, Atlanta, Georgia,
unpublished, update 1990.
[57 FR 42389, Sept. 14, 1992, as amended at 57 FR 49272, Oct. 30, 1992;
58 FR 21781, Apr. 23, 1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1288, Jan.
8, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71
FR 50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June
8, 2011; 77 FR 17781, Mar. 26, 2012]
Sec. 1910.1028 Benzene.
(a) Scope and application. (1) This section applies to all
occupational exposures to benzene. Chemical Abstracts Service Registry
No. 71-43-2, except as provided in paragraphs (a)(2) and (a)(3) of this
section.
(2) This section does not apply to:
(i) The storage, transportation, distribution, dispensing, sale or
use of gasoline, motor fuels, or other fuels containing benzene
subsequent to its final discharge from bulk wholesale storage
facilities, except that operations where gasoline or motor fuels are
dispensed for more than 4 hours per day in an indoor location are
covered by this section.
(ii) Loading and unloading operations at bulk wholesale storage
facilities which use vapor control systems for all loading and unloading
operations, except for the provisions of 29 CFR 1910.1200 as
incorporated into this section and the emergency provisions of
paragraphs (g) and (i)(4) of this section.
(iii) The storage, transportation, distribution or sale of benzene
or liquid mixtures containing more than 0.1 percent benzene in intact
containers or in transportation pipelines while sealed in such a manner
as to contain benzene
[[Page 237]]
vapors or liquid, except for the provisions of 29 CFR 1910.1200 as
incorporated into this section and the emergency provisions of
paragraphs (g) and (i)(4) of this section.
(iv) Containers and pipelines carrying mixtures with less than 0.1
percent benzene and natural gas processing plants processing gas with
less than 0.1 percent benzene.
(v) Work operations where the only exposure to benzene is from
liquid mixtures containing 0.5 percent or less of benzene by volume, or
the vapors released from such liquids until September 12, 1988; work
operations where the only exposure to benzene is from liquid mixtures
containing 0.3 percent or less of benzene by volume or the vapors
released from such liquids from September 12, 1988, to September 12,
1989; and work operations where the only exposure to benzene is from
liquid mixtures containing 0.1 percent or less of benzene by volume or
the vapors released from such liquids after September 12, 1989; except
that tire building machine operators using solvents with more than 0.1
percent benzene are covered by paragraph (i) of this section.
(vi) Oil and gas drilling, production and servicing operations.
(vii) Coke oven batteries.
(3) The cleaning and repair of barges and tankers which have
contained benzene are excluded from paragraph (f) methods of compliance,
paragraph (e)(1) exposure monitoring-general, and paragraph (e)(6)
accuracy of monitoring. Engineering and work practice controls shall be
used to keep exposures below 10 ppm unless it is proven to be not
feasible.
(b) Definitions. Action level means an airborne concentration of
benzene of 0.5 ppm calculated as an 8-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the
employer whose duties require the person to enter a regulated area, or
any person entering such an area as a designated representative of
employees for the purpose of exercising the right to observe monitoring
and measuring procedures under paragraph (l) of this section, or any
other person authorized by the Act or regulations issued under the Act.
Benzene (C6 H6) (CAS Registry No. 71-43-2)
means liquefied or gaseous benzene. It includes benzene contained in
liquid mixtures and the benzene vapors released by these liquids. It
does not include trace amounts of unreacted benzene contained in solid
materials.
Bulk wholesale storage facility means a bulk terminal or bulk plant
where fuel is stored prior to its delivery to wholesale customers.
Container means any barrel, bottle, can, cylinder, drum, reaction
vessel, storage tank, or the like, but does not include piping systems.
Day means any part of a calendar day.
Director means the Director of the National Institute for
Occupational Safety and Health, U.S. Department of Health and Human
Services, or designee.
Emergency means any occurrence such as, but not limited to,
equipment failure, rupture of containers, or failure of control
equipment which may or does result in an unexpected significant release
of benzene.
Employee exposure means exposure to airborne benzene which would
occur if the employee were not using respiratory protective equipment.
Regulated area means any area where airborne concentrations of
benzene exceed or can reasonably be expected to exceed, the permissible
exposure limits, either the 8-hour time weighted average exposure of 1
ppm or the short-term exposure limit of 5 ppm for 15 minutes.
Vapor control system means any equipment used for containing the
total vapors displaced during the loading of gasoline, motor fuel or
other fuel tank trucks and the displacing of these vapors through a
vapor processing system or balancing the vapor with the storage tank.
This equipment also includes systems containing the vapors displaced
from the storage tank during the unloading of the tank truck which
balance the vapors back to the tank truck.
[[Page 238]]
(c) Permissible exposure limits (PELs)--(1) Time-weighted average
limit (TWA). The employer shall assure that no employee is exposed to an
airborne concentration of benzene in excess of one part of benzene per
million parts of air (1 ppm) as an 8-hour time-weighted average.
(2) Short-term exposure limit (STEL). The employer shall assure that
no employee is exposed to an airborne concentration of benzene in excess
of five (5) ppm as averaged over any 15 minute period.
(d) Regulated areas. (1) The employer shall establish a regulated
area wherever the airborne concentration of benzene exceeds or can
reasonably be expected to exceed the permissible exposure limits, either
the 8-hour time weighted average exposure of 1 ppm or the short-term
exposure limit of 5 ppm for 15 minutes.
(2) Access to regulated areas shall be limited to authorized
persons.
(3) Regulated areas shall be determined from the rest of the
workplace in any manner that minimizes the number of employees exposed
to benzene within the regulated area.
(e) Exposure monitoring--(1) General. (i) Determinations of employee
exposure shall be made from breathing zone air samples that are
representative of each employee's average exposure to airborne benzene.
(ii) Representative 8-hour TWA employee exposures shall be
determined on the basis of one sample or samples representing the full
shift exposure for each job classification in each work area.
(iii) Determinations of compliance with the STEL shall be made from
15 minute employee breathing zone samples measured at operations where
there is reason to believe exposures are high, such as where tanks are
opened, filled, unloaded or gauged; where containers or process
equipment are opened and where benzene is used for cleaning or as a
solvent in an uncontrolled situation. The employer may use objective
data, such as measurements from brief period measuring devices, to
determine where STEL monitoring is needed.
(iv) Except for initial monitoring as required under paragraph
(e)(2) of this section, where the employer can document that one shift
will consistently have higher employee exposures for an operation, the
employer shall only be required to determine representative employee
exposure for that operation during the shift on which the highest
exposure is expected.
(2) Initial monitoring. (i) Each employer who has a place of
employment covered under paragraph (a)(1) of this section shall monitor
each of these workplaces and work operations to determine accurately the
airborne concentrations of benzene to which employees may be exposed.
(ii) The initial monitoring required under paragraph (e)(2)(i) of
this section shall be completed by 60 days after the effective date of
this standard or within 30 days of the introduction of benzene into the
workplace. Where the employer has monitored within one year prior to the
effective date of this standard and the monitoring satisfies all other
requirements of this section, the employer may rely on such earlier
monitoring results to satisfy the requirements of paragraph (e)(2)(i) of
this section.
(3) Periodic monitoring and monitoring frequency. (i) If the
monitoring required by paragraph (e)(2)(i) of this section reveals
employee exposure at or above the action level but at or below the TWA,
the employer shall repeat such monitoring for each such employee at
least every year.
(ii) If the monitoring required by paragraph (e)(2)(i) of this
section reveals employee exposure above the TWA, the employer shall
repeat such monitoring for each such employee at least every six (6)
months.
(iii) The employer may alter the monitoring schedule from every six
months to annually for any employee for whom two consecutive
measurements taken at least 7 days apart indicate that the employee
exposure has decreased to the TWA or below, but is at or above the
action level.
(iv) Monitoring for the STEL shall be repeated as necessary to
evaluate exposures of employees subject to short term exposures.
(4) Termination of monitoring. (i) If the initial monitoring
required by paragraph (e)(2)(i) of this section reveals
[[Page 239]]
employee exposure to be below the action level the employer may
discontinue the monitoring for that employee, except as otherwise
required by paragraph (e)(5) of this section.
(ii) If the periodic monitoring required by paragraph (e)(3) of this
section reveals that employee exposures, as indicated by at least two
consecutive measurements taken at least 7 days apart, are below the
action level the employer may discontinue the monitoring for that
employee, except as otherwise required by paragraph (e)(5).
(5) Additional monitoring. (i) The employer shall institute the
exposure monitoring required under paragraphs (e)(2) and (e)(3) of this
section when there has been a change in the production, process, control
equipment, personnel or work practices which may result in new or
additional exposures to benzene, or when the employer has any reason to
suspect a change which may result in new or additional exposures.
(ii) Whenever spills, leaks, ruptures or other breakdowns occur that
may lead to employee exposure, the employer shall monitor (using area or
personal sampling) after the cleanup of the spill or repair of the leak,
rupture or other breakdown to ensure that exposures have returned to the
level that existed prior to the incident.
(6) Accuracy of monitoring. Monitoring shall be accurate, to a
confidence level of 95 percent, to within plus or minus 25 percent for
airborne concentrations of benzene.
(7) Employee notification of monitoring results. (i) The employer
must, within 15 working days after the receipt of the results of any
monitoring performed under this section, notify each affected employee
of these results either individually in writing or by posting the
results in an appropriate location that is accessible to employees.
(ii) Whenever the PELs are exceeded, the written notification
required by paragraph (e)(7)(i) of this section shall contain the
corrective action being taken by the employer to reduce the employee
exposure to or below the PEL, or shall refer to a document available to
the employee which states the corrective actions to be taken.
(f) Methods of compliance--(1) Engineering controls and work
practices. (i) The employer shall institute engineering controls and
work practices to reduce and maintain employee exposure to benzene at or
below the permissible exposure limits, except to the extent that the
employer can establish that these controls are not feasible or where the
provisions of paragraph (f)(1)(iii) or (g)(1) of this section apply.
(ii) Wherever the feasible engineering controls and work practices
which can be instituted are not sufficient to reduce employee exposure
to or below the PELs, the employer shall use them to reduce employee
exposure to the lowest levels achievable by these controls and shall
supplement them by the use of respiratory protection which complies with
the requirements of paragraph (g) of this section.
(iii) Where the employer can document that benzene is used in a
workplace less than a total of 30 days per year, the employer shall use
engineering controls, work practice controls or respiratory protection
or any combination of these controls to reduce employee exposure to
benzene to or below the PELs, except that employers shall use
engineering and work practice controls, if feasible, to reduce exposure
to or below 10 ppm as an 8-hour TWA.
(2) Compliance program. (i) When any exposures are over the PEL, the
employer shall establish and implement a written program to reduce
employee exposure to or below the PEL primarily by means of engineering
and work practice controls, as required by paragraph (f)(1) of this
section.
(ii) The written program shall include a schedule for development
and implementation of the engineering and work practice controls. These
plans shall be reviewed and revised as appropriate based on the most
recent exposure monitoring data, to reflect the current status of the
program.
(iii) Written compliance programs shall be furnished upon request
for examination and copying to the Assistant Secretary, the Director,
affected employees and designated employee representatives.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer
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must provide each employee an appropriate respirator that complies with
the requirements of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Work operations for which the employer establishes that
compliance with either the TWA or STEL through the use of engineering
and work-practice controls is not feasible; for example, some
maintenance and repair activities, vessel cleaning, or other operations
for which engineering and work-practice controls are infeasible because
exposures are intermittent and limited in duration.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient, or are not required under
paragraph (f)(1)(iii) of this section, to reduce employee exposure to or
below the PELs.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii), (d)(3)(iii)(b)(1) and (2)), and (f)
through (m), which covers each employee required by this section to use
a respirator.
(ii) For air-purifying respirators, the employer must replace the
air-purifying element at the expiration of its service life or at the
beginning of each shift in which such elements are used, whichever comes
first.
(iii) If NIOSH approves an air-purifying element with an end-of-
service-life indicator for benzene, such an element may be used until
the indicator shows no further useful life.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(B) Provide employees with any organic vapor gas mask or any self-
contained breathing apparatus with a full facepiece to use for escape.
(C) Use an organic vapor cartridge or canister with powered and non-
powered air-purifying respirators, and a chin-style canister with full
facepiece gas masks.
(D) Ensure that canisters used with non-powered air-purifying
respirators have a minimum service life of four hours when tested at 150
ppm benzene at a flow rate of 64 liters per minute (LPM), a temperature
of 25 [deg]C, and a relative humidity of 85%; for canisters used with
tight-fitting or loose-fitting powered air-purifying respirators, the
flow rates for testing must be 115 LPM and 170 LPM, respectively.
(ii) Any employee who cannot use a negative-pressure respirator must
be allowed to use a respirator with less breathing resistance, such as a
powered air-purifying respirator or supplied-air respirator.
(h) Protective clothing and equipment. Personal protective clothing
and equipment shall be worn where appropriate to prevent eye contact and
limit dermal exposure to liquid benzene. Protective clothing and
equipment shall be provided by the employer at no cost to the employee
and the employer shall assure its use where appropriate. Eye and face
protection shall meet the requirements of 29 CFR 1910.133.
(i) Medical surveillance--(1) General. (i) The employer shall make
available a medical surveillance program for employees who are or may be
exposed to benzene at or above the action level 30 or more days per
year; for employees who are or may be exposed to benzene at or above the
PELs 10 or more days per year; for employees who have been exposed to
more than 10 ppm of benzene for 30 or more days in a year prior to the
effective date of the standard when employed by their current employer;
and for employees involved in the tire building operations called tire
building machine operators, who use solvents containing greater than 0.1
percent benzene.
(ii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician and that all laboratory tests are conducted by an accredited
laboratory.
(iii) The employer shall assure that persons other than licensed
physicians who administer the pulmonary function testing required by
this section shall complete a training course in
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spirometry sponsored by an appropriate governmental, academic or
professional institution.
(iv) The employer shall assure that all examinations and procedures
are provided without cost to the employee and at a reasonable time and
place.
(2) Initial examination. (i) Within 60 days of the effective date of
this standard, or before the time of initial assignment, the employer
shall provide each employee covered by paragraph (i)(1)(i) of this
section with a medical examination including the following elements:
(A) A detailed occupational history which includes:
(1) Past work exposure to benzene or any other hematological toxins,
(2) A family history of blood dyscrasias including hematological
neoplasms;
(3) A history of blood dyscrasias including genetic hemoglobin
abnormalities, bleeding abnormalities, abnormal function of formed blood
elements;
(4) A history of renal or liver dysfunction;
(5) A history of medicinal drugs routinely taken;
(6) A history of previous exposure to ionizing radiation and
(7) Exposure to marrow toxins outside of the current work situation.
(B) A complete physical examination.
(C) Laboratory tests. A complete blood count including a leukocyte
count with differential, a quantitative thrombocyte count, hematocrit,
hemoglobin, erythrocyte count and erythrocyte indices (MCV, MCH, MCHC).
The results of these tests shall be reviewed by the examining physician.
(D) Additional tests as necessary in the opinion of the examining
physician, based on alterations to the components of the blood or other
signs which may be related to benzene exposure; and
(E) For all workers required to wear respirators for at least 30
days a year, the physical examination shall pay special attention to the
cardiopulmonary system and shall include a pulmonary function test.
(ii) No initial medical examination is required to satisfy the
requirements of paragraph (i)(2)(i) of this section if adequate records
show that the employee has been examined in accordance with the
procedures of paragraph (i)(2)(i) of this section within the twelve
months prior to the effective date of this standard.
(3) Periodic examinations. (i) The employer shall provide each
employee covered under paragraph (i)(1)(i) of this section with a
medical examination annually following the previous examination. These
periodic examinations shall incude at least the following elements:
(A) A brief history regarding any new exposure to potential marrow
toxins, changes in medicinal drug use, and the appearance of physical
signs relating to blood disorders:
(B) A complete blood count including a leukocyte count with
differential, quantitative thrombocyte count, hemoglobin, hematocrit,
erythrocyte count and erythrocyte indices (MCV, MCH, MCHC); and
(C) Appropriate additional tests as necessary, in the opinion of the
examining physician, in consequence of alterations in the components of
the blood or other signs which may be related to benzene exposure.
(ii) Where the employee develops signs and symptoms commonly
associated with toxic exposure to benzene, the employer shall provide
the employee with an additional medical examination which shall include
those elements considered appropriate by the examining physician.
(iii) For persons required to use respirators for at least 30 days a
year, a pulmonary function test shall be performed every three (3)
years. A specific evaluation of the cardiopulmonary system shall be made
at the time of the pulmonary function test.
(4) Emergency examinations. (i) In addition to the surveillance
required by (i)(1)(i), if an employee is exposed to benzene in an
emergency situation, the employer shall have the employee provide a
urine sample at the end of the employee's shift and have a urinary
phenol test performed on the sample within 72 hours. The urine specific
gravity shall be corrected to 1.024.
(ii) If the result of the urinary phenol test is below 75 mg phenol/
L of urine, no further testing is required.
(iii) If the result of the urinary phenol test is equal to or
greater than 75 mg phenol/L of urine, the employer
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shall provide the employee with a complete blood count including an
erythrocyte count, leukocyte count with differential and thrombocyte
count at monthly intervals for a duration of three (3) months following
the emergency exposure.
(iv) If any of the conditions specified in paragraph (i)(5)(i) of
this section exists, then the further requirements of paragraph (i)(5)
of this section shall be met and the employer shall, in addition,
provide the employees with periodic examinations if directed by the
physician.
(5) Additional examinations and referrals. (i) Where the results of
the complete blood count required for the initial and periodic
examinations indicate any of the following abnormal conditions exist,
then the blood count shall be repeated within 2 weeks.
(A) The hemoglobin level or the hematocrit falls below the normal
limit [outside the 95% confidence interval (C.I.)] as determined by the
laboratory for the particular geographic area and/or these indices show
a persistent downward trend from the individual's pre-exposure norms;
provided these findings cannot be explained by other medical reasons.
(B) The thrombocyte (platelet) count varies more than 20 percent
below the employee's most recent values or falls outside the normal
limit (95% C.I.) as determined by the laboratory.
(C) The leukocyte count is below 4,000 per mm\3\ or there is an
abnormal differential count.
(ii) If the abnormality persists, the examining physician shall
refer the employee to a hematologist or an internist for further
evaluation unless the physician has good reason to believe such referral
is unnecessary. (See appendix C for examples of conditions where a
referral may be unnecessary.)
(iii) The employer shall provide the hematologist or internist with
the information required to be provided to the physician under paragraph
(i)(6) of this section and the medical record required to be maintained
by paragraph (k)(2)(ii) of this section.
(iv) The hematologist's or internist's evaluation shall include a
determination as to the need for additional tests, and the employer
shall assure that these tests are provided.
(6) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this regulation and its appendices;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's actual or representative exposure level:
(iv) A description of any personal protective equipment used or to
be used; and
(v) Information from previous employment-related medical
examinations of the affected employee which is not otherwise available
to the examining physician.
(7) Physician's written opinions. (i) For each examination under
this section, the employer shall obtain and provide the employee with a
copy of the examining physician's written opinion within 15 days of the
examination. The written opinion shall be limited to the following
information:
(A) The occupationally pertinent results of the medical examination
and tests;
(B) The physician's opinion concerning whether the employee has any
detected medical conditions which would place the employee's health at
greater than normal risk of material impairment from exposure to
benzene;
(C) The physician's recommended limitations upon the employee's
exposure to benzene or upon the employee's use of protective clothing or
equipment and respirators.
(D) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
resulting from benzene exposure which require further explanation or
treatment.
(ii) The written opinion obtained by the employer shall not reveal
specific records, findings and diagnoses that have no bearing on the
employee's ability to work in a benzene-exposed workplace.
(8) Medical removal plan. (i) When a physician makes a referral to a
hematologist/internist as required under paragraph (i)(5)(ii) of this
section, the
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employee shall be removed from areas where exposures may exceed the
action level until such time as the physician makes a determination
under paragraph (i)(8)(ii) of this section.
(ii) Following the examination and evaluation by the hematologist/
internist, a decision to remove an employee from areas where benzene
exposure is above the action level or to allow the employee to return to
areas where benzene exposure is above the action level shall be made by
the physician in consultation with the hematologist/internist. This
decision shall be communicated in writing to the employer and employee.
In the case of removal, the physician shall state the required probable
duration of removal from occupational exposure to benzene above the
action level and the requirements for future medical examinations to
review the decision.
(iii) For any employee who is removed pursuant to paragraph
(i)(8)(ii) of this section, the employer shall provide a follow-up
examination. The physician, in consultation with the hematologist/
internist, shall make a decision within 6 months of the date the
employee was removed as to whether the employee shall be returned to the
usual job or whether the employee should be removed permanently.
(iv) Whenever an employee is temporarily removed from benzene
exposure pursuant to paragraph (i)(8)(i) or (i)(8)(ii) of this section,
the employer shall transfer the employee to a comparable job for which
the employee is qualified (or can be trained for in a short period) and
where benzene exposures are as low as possible, but in no event higher
than the action level. The employer shall maintain the employee's
current wage rate, seniority and other benefits. If there is no such job
available, the employer shall provide medical removal protection
benefits until such a job becomes available or for 6 months, whichever
comes first.
(v) Whenever an employee is removed permanently from benzene
exposure based on a physician's recommendation pursuant to paragraph
(i)(8)(iii) of this section, the employee shall be given the opportunity
to transfer to another position which is available or later becomes
available for which the employee is qualified (or can be trained for in
a short period) and where benzene exposures are as low as possible but
in no event higher than the action level. The employer shall assure that
such employee suffers no reduction in current wage rate, seniority or
other benefits as a result of the transfer.
(9) Medical removal protection benefits. (i) The employer shall
provide to an employee 6 months of medical removal protection benefits
immediately following each occasion an employee is removed from exposure
to benzene because of hematological findings pursuant to paragraphs
(i)(8) (i) and (ii) of this section, unless the employee has been
transferred to a comparable job where benzene exposures are below the
action level.
(ii) For the purposes of this section, the requirement that an
employer provide medical removal protection benefits means that the
employer shall maintain the current wage rate, seniority and other
benefits of an employee as though the employee had not been removed.
(iii) The employer's obligation to provide medical removal
protection benefits to a removed employee shall be reduced to the extent
that the employee receives compensation for earnings lost during the
period of removal either from a publicly or employer-funded compensation
program, or from employment with another employer made possible by
virtue of the employee's removal.
(j) Communication of hazards--(1) Hazard communication--general.
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard Communication Standard (HCS)
(Sec. 1910.1200) for benzene.(ii) In classifying the hazards of benzene
at least the following hazards are to be addressed: Cancer; central
nervous system effects; blood effects; aspiration; skin, eye, and
respiratory tract irritation; and flammability.(iii) Employers shall
include benzene in the hazard communication program established to
comply with the HCS (Sec. 1910.1200). Employers shall ensure that each
employee has access to labels on containers of benzene and to
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safety data sheets, and is trained in accordance with the requirements
of HCS and paragraph (j)(3) of this section.
(2) Warning signs and labels. (i)The employer shall post signs at
entrances to regulated areas. The signs shall bear the following legend:
DANGER
BENZENE
MAY CAUSE CANCER
HIGHLY FLAMMABLE LIQUID AND VAPOR
DO NOT SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(ii) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (j)(2)(i) of this section:DANGER
BENZENE
CANCER HAZARD
FLAMMABLE--NO SMOKING
AUTHORIZED PERSONNEL ONLY
RESPIRATOR REQUIRED
(iii) The employer shall ensure that labels or other appropriate forms
of warning are provided for containers of benzene within the workplace.
There is no requirement to label pipes. The labels shall comply with the
requirements of paragraph (j)(1) of this section andSec. 1910.1200(f).
(iv) Prior to June 1, 2015, employers shall include the following legend
or similar language on the labels or other appropriate forms of warning:D
ANGER
CONTAINS BENZENE
CANCER HAZARD
(3) Information and training. (i) The employer shall provide
employees with information and training at the time of their initial
assignment to a work area where benzene is present. If exposures are
above the action level, employees shall be provided with information and
training at least annually thereafter.
(ii) The training program shall be in accordance with the
requirements of 29 CFR 1910.1200(h) (1) and (2), and shall include
specific information on benzene for each category of information
included in that section.
(iii) In addition to the information required under 29 CFR
1910.1200, the employer shall:
(A) Provide employees with an explanation of the contents of this
section, including Appendices A and B, and indicate to them where the
standard is available; and
(B) Describe the medical surveillance program required under
paragraph (i) of this section, and explain the information contained in
appendix C.
(k) Recordkeeping--(1) Exposure measurements. (i) The employer shall
establish and maintain an accurate record of all measurements required
by paragraph (e) of this section, in accordance with 29 CFR 1910.20.
(ii) This record shall include:
(A) The dates, number, duration, and results of each of the samples
taken, including a description of the procedure used to determine
representative employee exposures;
(B) A description of the sampling and analytical methods used;
(C) A description of the type of respiratory protective devices
worn, if any; and
(D) The name, social security number, job classification and
exposure levels of the employee monitored and all other employees whose
exposure the measurement is intended to represent.
(iii) The employer shall maintain this record for at least 30 years,
in accordance with 29 CFR 1910.20.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance required by paragraph (i) of this section, in accordance
with 29 CFR 1910.20.
(ii) This record shall include:
(A) The name and social security number of the employee;
(B) The employer's copy of the physician's written opinion on the
initial, periodic and special examinations, including results of medical
examinations and all tests, opinions and recommendations;
(C) Any employee medical complaints related to exposure to benzene;
(D) A copy of the information provided to the physician as required
by paragraphs (i)(6) (ii) through (v) of this section; and
(E) A copy of the employee's medical and work history related to
exposure to benzene or any other hematologic toxins.
(iii) The employer shall maintain this record for at least the
duration of employment plus 30 years, in accordance with 29 CFR 1910.20.
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(3) Availability. (i) The employer shall assure that all records
required to be maintained by this section shall be made available upon
request to the Assistant Secretary and the Director for examination and
copying.
(ii) Employee exposure monitoring records required by this paragraph
shall be provided upon request for examination and copying to employees,
employee representatives, and the Assistant Secretary in accordance with
29 CFR 1910.20 (a) through (e) and (g) through (i).
(iii) Employee medical records required by this paragraph shall be
provided upon request for examination and copying, to the subject
employee, to anyone having the specific written consent of the subject
employee, and to the Assistant Secretary in accordance with 29 CFR
1910.20.
(4) Transfer of records. The employer shall comply with the
requirements involving transfer of records as set forth in 29 CFR
1910.1020(h).
(l) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees, or their designated
representatives, an opportunity to observe the measuring or monitoring
of employee exposure to benzene conducted pursuant to paragraph (e) of
this section.
(2) Observation procedures. When observation of the measuring or
monitoring of employee exposure to benzene requires entry into areas
where the use of protective clothing and equipment or respirators is
required, the employer shall provide the observer with personal
protective clothing and equipment or respirators required to be worn by
employees working in the area, assure the use of such clothing and
equipment or respirators, and require the observer to comply with all
other applicable safety and health procedures.
(m) [Reserved]
(n) Appendices. The information contained in Appendices A, B, C, and
D is not intended, by itself, to create any additional obligations not
otherwise imposed or to detract from any existing obligations.
Appendix A toSec. 1910.1028--Substance Safety Data Sheet, Benzene
I. Substance Identification
A. Substance: Benzene.
B. Permissible Exposure: Except as to the use of gasoline, motor
fuels and other fuels subsequent to discharge from bulk terminals and
other exemptions specified inSec. 1910.1028(a)(2):
1. Airborne: The maximum time-weighted average (TWA) exposure limit
is 1 part of benzene vapor per million parts of air (1 ppm) for an 8-
hour workday and the maximum short-term exposure limit (STEL) is 5 ppm
for any 15-minute period.
2. Dermal: Eye contact shall be prevented and skin contact with
liquid benzene shall be limited.
C. Appearance and odor: Benzene is a clear, colorless liquid with a
pleasant, sweet odor. The odor of benzene does not provide adequate
warning of its hazard.
II. Health Hazard Data
A. Ways in which benzene affects your health. Benzene can affect
your health if you inhale it, or if it comes in contact with your skin
or eyes. Benzene is also harmful if you happen to swallow it.
B. Effects of overexposure. 1. Short-term (acute) overexposure: If
you are overexposed to high concentrations of benzene, well above the
levels where its odor is first recognizable, you may feel breathless,
irritable, euphoric, or giddy; you may experience irritation in eyes,
nose, and respiratory tract. You may develop a headache, feel dizzy,
nauseated, or intoxicated. Severe exposures may lead to convulsions and
loss of consciousness.
2. Long-term (chronic) exposure. Repeated or prolonged exposure to
benzene, even at relatively low concentrations, may result in various
blood disorders, ranging from anemia to leukemia, an irreversible, fatal
disease. Many blood disorders associated with benzene exposure may occur
without symptoms.
III. Protective Clothing and Equipment
A. Respirators. Respirators are required for those operations in
which engineering controls or work practice controls are not feasible to
reduce exposure to the permissible level. However, where employers can
document that benzene is present in the workplace less than 30 days a
year, respirators may be used in lieu of engineering controls. If
respirators are worn, they must have joint Mine Safety and Health
Administration and the National Institute for Occupational Safety and
Health (NIOSH) seal of approval, and cartridge or canisters must be
replaced before the end of their service life, or the end of the shift,
whichever occurs first. If you experience difficulty breathing while
wearing a
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respirator, you may request a positive pressure respirator from your
employer. You must be thoroughly trained to use the assigned respirator,
and the training will be provided by your employer.
B. Protective Clothing. You must wear appropriate protective
clothing (such as boots, gloves, sleeves, aprons, etc.) over any parts
of your body that could be exposed to liquid benzene.
C. Eye and Face Protection. You must wear splash-proof safety
goggles if it is possible that benzene may get into your eyes. In
addition, you must wear a face shield if your face could be splashed
with benzene liquid.
IV. Emergency and First Aid Procedures
A. Eye and face exposure. If benzene is splashed in your eyes, wash
it out immediately with large amounts of water. If irritation persists
or vision appears to be affected see a doctor as soon as possible.
B. Skin exposure. If benzene is spilled on your clothing or skin,
remove the contaminated clothing and wash the exposed skin with large
amounts of water and soap immediately. Wash contaminated clothing before
you wear it again.
C. Breathing. If you or any other person breathes in large amounts
of benzene, get the exposed person to fresh air at once. Apply
artificial respiration if breathing has stopped. Call for medical
assistance or a doctor as soon as possible. Never enter any vessel or
confined space where the benzene concentration might be high without
proper safety equipment and at least one other person present who will
stay outside. A life line should be used.
D. Swallowing. If benzene has been swallowed and the patient is
conscious, do not induce vomiting. Call for medical assistance or a
doctor immediately.
V. Medical Requirements
If you are exposed to benzene at a concentration at or above 0.5 ppm
as an 8-hour time-weighted average, or have been exposed at or above 10
ppm in the past while employed by your current employer, your employer
is required to provide a medical examination and history and laboratory
tests within 60 days of the effective date of this standard and annually
thereafter. These tests shall be provided without cost to you. In
addition, if you are accidentally exposed to benzene (either by
ingestion, inhalation, or skin/eye contact) under emergency conditions
known or suspected to constitute toxic exposure to benzene, your
employer is required to make special laboratory tests available to you.
VI. Observation of Monitoring
Your employer is required to perform measurements that are
representative of your exposure to benzene and you or your designated
representative are entitled to observe the monitoring procedure. You are
entitled to observe the steps taken in the measurement procedure, and to
record the results obtained. When the monitoring procedure is taking
place in an area where respirators or personal protective clothing and
equipment are required to be worn, you or your representative must also
be provided with, and must wear the protective clothing and equipment.
VII. Access to Records
You or your representative are entitled to see the records of
measurements of your exposure to benzene upon written request to your
employer. Your medical examination records can be furnished to yourself,
your physician or designated representative upon request by you to your
employer.
VIII. Precautions for Safe Use, Handling and Storage
Benzene liquid is highly flammable. It should be stored in tightly
closed containers in a cool, well ventilated area. Benzene vapor may
form explosive mixtures in air. All sources of ignition must be
controlled. Use nonsparking tools when opening or closing benzene
containers. Fire extinguishers, where provided, must be readily
available. Know where they are located and how to operate them. Smoking
is prohibited in areas where benzene is used or stored. Ask your
supervisor where benzene is used in your area and for additional plant
safety rules.
Appendix B toSec. 1910.1028--Substance Technical Guidelines, Benzene
I. Physical and Chemical Data
A. Substance identification.
1. Synonyms: Benzol, benzole, coal naphtha, cyclohexatriene, phene,
phenyl hydride, pyrobenzol. (Benzin, petroleum benzin and Benzine do not
contain benzene).
2. Formula: C6 H6 (CAS Registry Number: 71-43-
2)
B. Physical data.
1. Boiling Point (760 mm Hg); 80.1 [deg]C (176 [deg]F)
2. Specific Gravity (water=1): 0.879
3. Vapor Density (air=1): 2.7
4. Melting Point: 5.5 [deg]C (42 [deg]F)
5. Vapor Pressure at 20 [deg]C (68 [deg]F): 75 mm Hg
6. Solubility in Water: .06%
7. Evaporation Rate (ether=1): 2.8
8. Appearance and Odor: Clear, colorless liquid with a distinctive
sweet odor.
II. Fire, Explosion, and Reactivity Hazard Data
A. Fire.
1. Flash Point (closed cup): -11 [deg]C (12 [deg]F)
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2. Autoignition Temperature: 580 [deg]C (1076 [deg]F)
3. Flammable limits in Air. % by Volume: Lower: 1.3%, Upper: 7.5%
4. Extinguishing Media: Carbon dioxide, dry chemical, or foam.
5. Special Fire-Fighting procedures: Do not use solid stream of
water, since stream will scatter and spread fire. Fine water spray can
be used to keep fire-exposed containers cool.
6. Unusual fire and explosion hazards: Benzene is a flammable
liquid. Its vapors can form explosive mixtures. All ignition sources
must be controlled when benzene is used, handled, or stored. Where
liquid or vapor may be released, such areas shall be considered as
hazardous locations. Benzene vapors are heavier than air; thus the
vapors may travel along the ground and be ignited by open flames or
sparks at locations remote from the site at which benzene is handled.
7. Benzene is classified as a 1 B flammable liquid for the purpose
of conforming to the requirements of 29 CFR 1910.106. A concentration
exceeding 3,250 ppm is considered a potential fire explosion hazard.
Locations where benzene may be present in quantities sufficient to
produce explosive or ignitable mixtures are considered Class I Group D
for the purposes of conforming to the requirements of 29 CFR 1910.309.
B. Reactivity.
1. Conditions contributing to instability: Heat.
2. Incompatibility: Heat and oxidizing materials.
3. Hazardous decomposition products: Toxic gases and vapors (such as
carbon monoxide).
III. Spill and Leak Procedures
A. Steps to be taken if the material is released or spilled. As much
benzene as possible should be absorbed with suitable materials, such as
dry sand or earth. That remaining must be flushed with large amounts of
water. Do not flush benzene into a confined space, such as a sewer,
because of explosion danger. Remove all ignition sources. Ventilate
enclosed places.
B. Waste disposal method. Disposal methods must conform to other
jurisdictional regulations. If allowed, benzene may be disposed of: (a)
By absorbing it in dry sand or earth and disposing in a sanitary
landfill; (b) if small quantities, by removing it to a safe location
from buildings or other combustible sources, pouring it in dry sand or
earth and cautiously igniting it; and (c) if large quantities, by
atomizing it in a suitable combustion chamber.
IV. Miscellaneous Precautions
A. High exposure to benzene can occur when transferring the liquid
from one container to another. Such operations should be well ventilated
and good work practices must be established to avoid spills.
B. Use non-sparking tools to open benzene containers which are
effectively grounded and bonded prior to opening and pouring.
C. Employers must advise employees of all plant areas and operations
where exposure to benzene could occur. Common operations in which high
exposures to benzene may be encountered are: the primary production and
utilization of benzene, and transfer of benzene.
Appendix C toSec. 1910.1028--Medical Surveillance Guidelines for
Benzene
I. Route of Entry
Inhalation; skin absorption.
II. Toxicology
Benzene is primarily an inhalation hazard. Systemic absorption may
cause depression of the hematopoietic system, pancytopenia, aplastic
anemia, and leukemia. Inhalation of high concentrations can affect
central nervous system function. Aspiration of small amounts of liquid
benzene immediately causes pulmonary edema and hemorrhage of pulmonary
tissue. There is some absorption through the skin. Absorption may be
more rapid in the case of abraded skin, and benzene may be more readily
absorbed if it is present in a mixture or as a contaminant in solvents
which are readily absorbed. The defatting action of benzene may produce
primary irritation due to repeated or prolonged contact with the skin.
High concentration are irritating to the eyes and the mucuous membranes
of the nose, and respiratory tract.
III. Signs and Symptoms
Direct skin contact with benzene may cause erythema. Repeated or
prolonged contact may result in drying, scaling dermatitis, or
development of secondary skin infections. In addition, there is benzene
absorption through the skin. Local effects of benzene vapor or liquid on
the eye are slight. Only at very high concentrations is there any
smarting sensation in the eye. Inhalation of high concentrations of
benzene may have an initial stimulatory effect on the central nervous
system characterized by exhilaration, nervous excitation, and/or
giddiness, followed by a period of depression, drowsiness, or fatigue. A
sensation of tightness in the chest accompanied by breathlessness may
occur and ultimately the victim may lose consciousness. Tremors,
convulsions and death may follow from respiratory paralysis or
circulatory collapse in a few minutes to several hours following severe
exposures.
The detrimental effect on the blood-forming system of prolonged
exposure to small
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quantities of benzene vapor is of extreme importance. The hematopoietic
system is the chief target for benzene's toxic effects which are
manifested by alterations in the levels of formed elements in the
peripheral blood. These effects have occurred at concentrations of
benzene which may not cause irritation of mucous membranes, or any
unpleasant sensory effects. Early signs and symptoms of benzene
morbidity are varied, often not readily noticed and non-specific.
Subjective complaints of headache, dizziness, and loss of appetite may
precede or follow clinical signs. Rapid pulse and low blood pressure, in
addition to a physical appearance of anemia, may accompany a subjective
complaint of shortness of breath and excessive tiredness. Bleeding from
the nose, gums, or mucous membranes, and the development of purpuric
spots (small bruises) may occur as the condition progresses. Clinical
evidence of leukopenia, anemia, and thrombocytopenia, singly or in
combination, has been frequently reported among the first signs.
Bone marrow may appear normal, aplastic, or hyperplastic, and may
not, in all situations, correlate with peripheral blood forming tissues.
Because of variations in the susceptibility to benzene morbidity, there
is no ``typical'' blood picture. The onset of effects of prolonged
benzene exposure may be delayed for many months or years after the
actual exposure has ceased and identification or correlation with
benzene exposure must be sought out in the occupational history.
IV. Treatment of Acute Toxic Effects
Remove from exposure immediately. Make sure you are adequately
protected and do not risk being overcome by fumes. Give oxygen or
artificial resuscitation if indicated. Flush eyes, wash skin if
contaminated and remove all contaminated clothing. Symptoms of
intoxication may persist following severe exposures. Recovery from mild
exposures is usually rapid and complete.
V. Surveillance and Preventive Considerations
A. General
The principal effects of benzene exposure which form the basis for
this regulation are pathological changes in the hematopoietic system,
reflected by changes in the peripheral blood and manifesting clinically
as pancytopenia, aplastic anemia, and leukemia. Consequently, the
medical surveillance program is designed to observe, on a regular basis,
blood indices for early signs of these effects, and although early signs
of leukemia are not usually available, emerging diagnostic technology
and innovative regimes make consistent surveillance for leukemia, as
well as other hematopoietic effects, essential.
Initial examinations are to be provided within 60 days of the
effective date of this standard, or at the time of initial assignment,
and periodic examinations annually thereafter. There are special
provisions for medical tests in the event of hematologic abnormalities
or for emergency situations.
The blood values which require referral to a hematologist or
internist are noted in the standard in paragraph (i)(5). The standard
specifies that blood abnormalities that persist must be referred
``unless the physician has good reason to believe such referral is
unnecessary'' (paragraph (i)(5)). Examples of conditions that could make
a referral unnecessary despite abnormal blood limits are iron or folate
deficiency, menorrhagia, or blood loss due to some unrelated medical
abnormality.
Symptoms and signs of benzene toxicity can be non-specific. Only a
detailed history and appropriate investigative procedures will enable a
physician to rule out or confirm conditions that place the employee at
increased risk. To assist the examining physician with regard to which
laboratory tests are necessary and when to refer an employee to the
specialist, OSHA has established the following guidelines.
B. Hematology Guidelines
A minimum battery of tests is to be performed by strictly
standardized methods.
1. Red cell, white cell, platelet counts, white blood cell
differential, hematacrit and red cell indices must be performed by an
accredited laboratory. The normal ranges for the red cell and white cell
counts are influenced by altitude, race, and sex, and therefore should
be determined by the accredited laboratory in the specific area where
the tests are performed.
Either a decline from an absolute normal or an individual's base
line to a subnormal value or a rise to a supra-normal value, are
indicative of potential toxicity, particularly if all blood parameters
decline. The normal total white blood count is approximately 7,200/mm\3\
plus or minus 3,000. For cigarette smokers the white count may be higher
and the upper range may be 2,000 cells higher than normal for the
laboratory. In addition, infection, allergies and some drugs may raise
the white cell count. The normal platelet count is approximately 250,000
with a range of 140,000 to 400,000. Counts outside this range should be
regarded as possible evidence of benzene toxicity.
Certain abnormalities found through routine screening are of greater
significance in the benzene-exposed worker and require prompt
consultation with a specialist, namely:
a. Thrombocytopenia.
b. A trend of decreasing white cell, red cell, or platelet indices
in an individual over time
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is more worrisome than an isolated abnormal finding at one test time.
The importance of trend highlights the need to compare an individual's
test results to baseline and/or previous periodic tests.
c. A constellation or pattern of abnormalities in the different
blood indices is of more significance than a single abnormality. A low
white count not associated with any abnormalities in other cell indices
may be a normal statistical variation, whereas if the low white count is
accompanied by decreases in the platelet and/or red cell indices, such a
pattern is more likely to be associated with benzene toxicity and merits
thorough investigation.
Anemia, leukopenia, macrocytosis or an abnormal differential white
blood cell count should alert the physician to further investigate and/
or refer the patient if repeat tests confirm the abnormalities. If
routine screening detects an abnormality, follow-up tests which may be
helpful in establishing the etiology of the abnormality are the
peripheral blood smear and the reticulocyte count.
The extreme range of normal for reticulocytes is 0.4 to 2.5 percent
of the red cells, the usual range being 0.5 to 1.2 percent of the red
cells, but the typical value is in the range of 0.8 to 1.0 percent. A
decline in reticulocytes to levels of less than 0.4 percent is to be
regarded as possible evidence (unless another specific cause is found)
of benzene toxicity requiring accelerated surveillance. An increase in
reticulocyte levels to about 2.5 percent may also be consistent with
(but is not as characteristic of) benzene toxicity.
2. An important diagnostic test is a careful examination of the
peripheral blood smear. As with reticulocyte count the smear should be
with fresh uncoagulated blood obtained from a needle tip following
venipuncture or from a drop of earlobe blood (capillary blood). If
necessary, the smear may, under certain limited conditions, be made from
a blood sample anticoagulated with EDTA (but never with oxalate or
heparin). When the smear is to be prepared from a specimen of venous
blood which has been collected by a commercial Vacutainer [supreg] type
tube containing neutral EDTA, the smear should be made as soon as
possible after the venesection. A delay of up to 12 hours is permissible
between the drawing of the blood specimen into EDTA and the preparation
of the smear if the blood is stored at refrigerator (not freezing)
temperature.
3. The minimum mandatory observations to be made from the smear are:
a. The differential white blood cell count.
b. Description of abnormalities in the appearance of red cells.
c. Description of any abnormalities in the platelets.
d. A careful search must be made throughout of every blood smear for
immature white cells such as band forms (in more than normal proportion,
i.e., over 10 percent of the total differential count), any number of
metamyelocytes, myelocytes or myeloblasts. Any nucleate or
multinucleated red blood cells should be reported. Large ``giant''
platelets or fragments of megakaryocytes must be recognized.
An increase in the proportion of band forms among the neutrophilic
granulocytes is an abnormality deserving special mention, for it may
represent a change which should be considered as an early warning of
benzene toxicity in the absence of other causative factors (most
commonly infection). Likewise, the appearance of metamyelocytes, in the
absence of another probable cause, is to be considered a possible
indication of benzene-induced toxicity.
An upward trend in the number of basophils, which normally do not
exceed about 2.0 percent of the total white cells, is to be regarded as
possible evidence of benzene toxicity. A rise in the eosinophil count is
less specific but also may be suspicious of toxicity if the rises above
6.0 percent of the total white count.
The normal range of monocytes is from 2.0 to 8.0 percent of the
total white count with an average of about 5.0 percent. About 20 percent
of individuals reported to have mild but persisting abnormalities caused
by exposure to benzene show a persistent monocytosis. The findings of a
monocyte count which persists at more than 10 to 12 percent of the
normal white cell count (when the total count is normal) or persistence
of an absolute monocyte count in excess of 800/mm\3\ should be regarded
as a possible sign of benzene-induced toxicity.
A less frequent but more serious indication of benzene toxicity is
the finding in the peripheral blood of the so-called ``pseudo'' (or
acquired) Pelger-Huet anomaly. In this anomaly many, or sometimes the
majority, of the neutrophilic granulocytes possess two round nuclear
segements--less often one or three round segments--rather than three
normally elongated segments. When this anomaly is not hereditary, it is
often but not invariably predictive of subsequent leukemia. However,
only about two percent of patients who ultimately develop acute
myelogenous leukemia show the acquired Pelger-Huet anomaly. Other tests
that can be administered to investigate blood abnormalities are
discussed below; however, such procedures should be undertaken by the
hematologist.
An uncommon sign, which cannot be detected from the smear, but can
be elicited by a ``sucrose water test'' of peripheral blood, is
transient paroxysmal nocturnal hemoglobinuria (PNH), which may first
occur insidiously during a period of established aplastic anemia, and
may be followed within
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one to a few years by the appearance of rapidly fatal acute myelogenous
leukemia. Clinical detection of PNH, which occurs in only one or two
percent of those destined to have acute myelogenous leukemia, may be
difficult; if the ``sucrose water test'' is positive, the somewhat more
definitive Ham test, also known as the acid-serum hemolysis test, may
provide confirmation.
e. Individuals documented to have developed acute myelogenous
leukemia years after initial exposure to benzene may have progressed
through a preliminary phase of hematologic abnormality. In some
instances pancytopenia (i.e., a lowering in the counts of all
circulating blood cells of bone marrow origin, but not to the extent
implied by the term ``aplastic anemia'') preceded leukemia for many
years. Depression of a single blood cell type or platelets may represent
a harbinger of aplasia or leukemia. The finding of two or more
cytopenias, or pancytopenia in a benzene-exposed individual, must be
regarded as highly suspicious of more advanced although still
reversible, toxicity. ``Pancytopenia'' coupled with the appearance of
immature cells (myelocytes, myeloblasts, erythroblasts, etc.), with
abnormal cells (pseudo Pelger-Huet anomaly, atypical nuclear
heterochromatin, etc.), or unexplained elevations of white blood cells
must be regarded as evidence of benzene overexposure unless proved
otherwise. Many severely aplastic patients manifested the ominous
finding of 5-10 percent myeloblasts in the marrow, occasional
myeloblasts and myelocytes in the blood and 20-30% monocytes. It is
evident that isolated cytopenias, pancytopenias, and even aplastic
anemias induced by benzene may be reversible and complete recovery has
been reported on cessation of exposure. However, since any of these
abnormalities is serious, the employee must immediately be removed from
any possible exposure to benzene vapor. Certain tests may substantiate
the employee's prospects for progression or regression. One such test
would be an examination of the bone marrow, but the decision to perform
a bone marrow aspiration or needle biopsy is made by the hematologist.
The findings of basophilic stippling in circulating red blood cells
(usually found in 1 to 5% of red cells following marrow injury), and
detection in the bone marrow of what are termed ``ringed sideroblasts''
must be taken seriously, as they have been noted in recent years to be
premonitory signs of subsequent leukemia.
Recently peroxidase-staining of circulating or marrow neutrophil
granulocytes, employing benzidine dihydrochloride, have revealed the
disappearance of, or diminution in, peroxidase in a sizable proportion
of the granulocytes, and this has been reported as an early sign of
leukemia. However, relatively few patients have been studied to date.
Granulocyte granules are normally strongly peroxidase positive. A steady
decline in leukocyte alkaline phosphatase has also been reported as
suggestive of early acute leukemia. Exposure to benzene may cause an
early rise in serum iron, often but not always associated with a fall in
the reticulocyte count. Thus, serial measurements of serum iron levels
may provide a means of determining whether or not there is a trend
representing sustained suppression of erythropoiesis.
Measurement of serum iron, determination of peroxidase and of
alkaline phosphatase activity in peripheral granulocytes can be
performed in most pathology laboratories. Peroxidase and alkaline
phosphatase staining are usually undertaken when the index of suspecion
for leukemia is high.
Appendix D toSec. 1910.1028--Sampling and Analytical Methods for
Benzene Monitoring and Measurement Procedures
Measurements taken for the purpose of determining employee exposure
to benzene are best taken so that the representative average 8-hour
exposure may be determined from a single 8-hour sample or two (2) 4-hour
samples. Short-time interval samples (or grab samples) may also be used
to determine average exposure level if a minimum of five measurements
are taken in a random manner over the 8-hour work shift. Random sampling
means that any portion of the work shift has the same change of being
sampled as any other. The arithmetic average of all such random samples
taken on one work shift is an estimate of an employee's average level of
exposure for that work shift. Air samples should be taken in the
employee's breathing zone (air that would most nearly represent that
inhaled by the employee). Sampling and analysis must be performed with
procedures meeting the requirements of the standard.
There are a number of methods available for monitoring employee
exposures to benzene. The sampling and analysis may be performed by
collection of the benzene vaptor or charcoal absorption tubes, with
subsequent chemical analysis by gas chromatography. Sampling and
analysis may also be performed by portable direct reading instruments,
real-time continuous monitoring systems, passive dosimeters or other
suitable methods. The employer has the obligation of selecting a
monitoring method which meets the accuracy and precision requirements of
the standard under his unique field conditions. The standard requires
that the method of monitoring must have an accuracy, to a 95 percent
confidence level, of not less than plus or minus 25 percent for
concentrations of benzene greater than or equal to 0.5 ppm.
The OSHA Laboratory modified NIOSH Method S311 and evaluated it at a
benzene air concentration of 1 ppm. A procedure for
[[Page 251]]
determining the benzene concentration in bulk material samples was also
evalauted. This work, reported in OSHA Laboratory Method No. 12,
includes the following two analytical procedures:
I. OSHA Method 12 for Air Samples
Analyte: Benzene
Matrix: Air
Procedure: Adsorption on charcoal, desorption with carbon disulfide,
analysis by GC.
Detection limit: 0.04 ppm
Recommended air volume and sampling rate: 10L to 0.2 L/min.
1. Principle of the Method.
1.1 A known volume of air is drawn through a charcoal tube to trap
the organic vapors present.
1.2. The charcoal in the tube is transferred to a small, stoppered
vial, and the anlyte is desorbed with carbon disulfide.
1.3. An aliquot of the desorbed sample is injected into a gas
chromatograph.
1.4 The area of the resulting peak is determined and compared with
areas obtained from standards.
2. Advantages and disadvantages of the method.
2.1 The sampling device is small, portable, and involved no liquids.
Interferences are minimal, and most of those which do occur can be
eliminated by altering chromatographic conditions. The samples are
analyzed by means of a quick, instrumental method.
2.2 The amount of sample which can be taken is limited by the number
of milligrams that the tube will hold before overloading. When the
sample value obtained for the backup section of the charcoal tube
exceeds 25 percent of that found on the front section, the possibility
of sample loss exists.
3. Apparatus.
3.1 A calibrated personal sampling pump whose flow can be determined
within 5 percent at the recommended flow rate.
3.2. Charcoal tubes: Glass with both ends flame sealed, 7 cm long
with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40 mesh
activated charcoal separated by a 2-mm portion of urethane foam. The
activated charcoal is prepared from coconut shells and is fired at 600
[deg]C prior to packing. The adsorbing section contains 100 mg of
charcoal, the back-up section 50 mg. A 3-mm portion of urethane foam is
placed between the outlet end of the tube and the back-up section. A
plug of silanized glass wool is placed in front of the adsorbing
section. The pressure drop across the tube must be less than one inch of
mercury at a flow rate of 1 liter per minute.
3.3. Gas chromatograph equipped with a flame ionization detector.
3.4. Column (10-ft x \1/8\-in stainless steel) packed with 80/100
Supelcoport coated with 20 percent SP 2100, 0.1 percent CW 1500.
3.5. An electronic integrator or some other suitable method for
measuring peak area.
3.6. Two-milliliter sample vials with Teflon-lined caps.
3.7. Microliter syringes: 10-microliter (10-[micro]L syringe, and
other convenient sizes for making standards, 1-[micro]L syringe for
sample injections.
3.8. Pipets: 1.0 mL delivery pipets
3.9. Volumetric flasks: convenient sizes for making standard
solutions.
4. Reagents.
4.1. Chromatographic quality carbon disulfide (CS2). Most
commercially available carbon disulfide contains a trace of benzene
which must be removed. It can be removed with the following procedure:
Heat under reflux for 2 to 3 hours, 500 mL of carbon disulfide, 10
mL concentrated sulfuric acid, and 5 drops of concentrated nitric acid.
The benzene is converted to nitrobenzene. The carbon disulfide layer is
removed, dried with anhydrous sodium sulfate, and distilled. The
recovered carbon disulfide should be benzene free. (It has recently been
determined that benzene can also be removed by passing the carbon
disulfide through 13x molecular sieve).
4.2. Benzene, reagent grade.
4.3. p-Cymene, reagent grade, (internal standard).
4.4. Desorbing reagent. The desorbing reagent is prepared by adding
0.05 mL of p-cymene per milliliter of carbon disulfide. (The internal
standard offers a convenient means correcting analytical response for
slight inconsistencies in the size of sample injections. If the external
standard technique is preferred, the internal standard can be
eliminated).
4.5. Purified GC grade helium, hydrogen and air.
5. Procedure.
5.1. Cleaning of equipment. All glassware used for the laboratory
analysis should be properly cleaned and free of organics which could
interfere in the analysis.
5.2. Calibration of personal pumps. Each pump must be calibrated
with a representative charcoal tube in the line.
5.3. Collection and shipping of samples.
5.3.1. Immediately before sampling, break the ends of the tube to
provide an opening at least one-half the internal diameter of the tube
(2 mm).
5.3.2. The smaller section of the charcoal is used as the backup and
should be placed nearest the sampling pump.
5.3.3. The charcoal tube should be placed in a vertical position
during sampling to minimize channeling through the charcoal.
5.3.4 Air being sampled should not be passed through any hose or
tubing before entering the charcoal tube.
5.3.5. A sample size of 10 liters is recommended. Sample at a flow
rate of approximately 0.2 liters per minute. The flow rate
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should be known with an accuracy of at least 5
percent.
5.3.6. The charcoal tubes should be capped with the supplied plastic
caps immediately after sampling.
5.3.7. Submit at least one blank tube (a charcoal tube subjected to
the same handling procedures, without having any air drawn through it)
with each set of samples.
5.3.8. Take necessary shipping and packing precautions to minimize
breakage of samples.
5.4. Analysis of samples.
5.4.1. Preparation of samples. In preparation for analysis, each
charcoal tube is scored with a file in front of the first section of
charcoal and broken open. The glass wool is removed and discarded. The
charcoal in the first (larger) section is transferred to a 2-ml vial.
The separating section of foam is removed and discarded; the second
section is transferred to another capped vial. These two sections are
analyzed separately.
5.4.2. Desorption of samples. Prior to analysis, 1.0 mL of desorbing
solution is pipetted into each sample container. The desorbing solution
consists of 0.05 [micro]L internal standard per mL of carbon disulfide.
The sample vials are capped as soon as the solvent is added. Desorption
should be done for 30 minutes with occasional shaking.
5.4.3. GC conditions. Typical operating conditions for the gas
chromatograph are:
1.30 mL/min (60 psig) helium carrier gas flow.
2.30 mL/min (40 psig) hydrogen gas flow to detector.
3.240 mL/min (40 psig) air flow to detector.
4.150 [deg]C injector temperature.
5.250 [deg]C detector temperature.
6.100 [deg]C column temperature.
5.4.4. Injection size. 1 [micro]L.
5.4.5. Measurement of area. The peak areas are measured by an
electronic integrator or some other suitable form of area measurement.
5.4.6. An internal standard procedure is used. The integrator is
calibrated to report results in ppm for a 10 liter air sample after
correction for desorption efficiency.
5.5. Determination of desorption efficiency.
5.5.1. Importance of determination. The desorption efficiency of a
particular compound can vary from one laboratory to another and from one
lot of chemical to another. Thus, it is necessary to determine, at least
once, the percentage of the specific compound that is removed in the
desorption process, provided the same batch of charcoal is used.
5.5.2. Procedure for determining desorption efficiency. The
reference portion of the charcoal tube is removed. To the remaining
portion, amounts representing 0.5X, 1X, and 2X and (X represents target
concentration) based on a 10 L air sample are injected into several
tubes at each level. Dilutions of benzene with carbon disulfide are made
to allow injection of measurable quantities. These tubes are then
allowed to equilibrate at least overnight. Following equilibration they
are analyzed following the same procedure as the samples. Desorption
efficiency is determined by dividing the amount of benzene found by
amount spiked on the tube.
6. Calibration and standards. A series of standards varying in
concentration over the range of interest is prepared and analyzed under
the same GC conditions that will be used on the samples. A calibration
curve is prepared by plotting concentration ([micro]g/mL) versus peak
area.
7. Calculations. Benzene air concentration can be calculated from
the following equation:
mg/m\3\=(A)(B)/(C)(D)
Where:
A=[micro]g/mL benzene, obtained from the calibration curve
B=desorption volume (1 mL)
C=Liters of air sampled
D=desorption efficiency
The concentration in mg/m\3\ can be converted to ppm (at 25[deg] and
760 mm) with following equation:
ppm=(mg/m\3\)(24.46)/(78.11)
Where:
24.46=molar volume of an ideal gas
25 [deg]C and 760 mm
78.11=molecular weight of benzene
8. Backup Data.
8.1 Detection limit--Air Samples.
The detection limit for the analytical procedure is 1.28 ng with a
coefficient of variation of 0.023 at this level. This would be
equivalent to an air concentration of 0.04 ppm for a 10 L air sample.
This amount provided a chromatographic peak that could be identifiable
in the presence of possible interferences. The detection limit data were
obtained by making 1 [micro]L injections of a 1.283 [micro]g/mL
standard.
------------------------------------------------------------------------
Area
Injection Count
------------------------------------------------------------------------
1....................................... 655.4
2....................................... 617.5
3....................................... 662.0 X=640.2
4....................................... 641.1 SD=14.9
5....................................... 636.4 CV=0.023
6....................................... 629.2 .....................
------------------------------------------------------------------------
8.2. Pooled coefficient of variation--Air Samples. The pooled
coefficient of variation for the analytical procedure was determined by
1 [micro]L replicate injections of analytical standards. The standards
were 16.04, 32.08, and 64.16 [micro]g/mL, which are equivalent to 0.5,
1.0, and 2.0 ppm for a 10 L air sample respectively.
[[Page 253]]
------------------------------------------------------------------------
Area Counts
Injection ------------------------------------
0.5 ppm 1.0 ppm 2.0 ppm
------------------------------------------------------------------------
1.................................. 3996.5 8130.2 16481
2.................................. 4059.4 8235.6 16493
3.................................. 4052.0 8307.9 16535
4.................................. 4027.2 8263.2 16609
5.................................. 4046.8 8291.1 16552
6.................................. 4137.9 8288.8 16618
X= 4053.3 8254.0 16548.3
SD= 47.2 62.5 57.1
CV= 0.0116 0.0076 0.0034
CV=0.008........................... .......... .......... ...........
------------------------------------------------------------------------
8.3. Storage data--Air Samples
Samples were generated at 1.03 ppm benzene at 80% relative humidity,
22 [deg]C, and 643 mm. All samples were taken for 50 minutes at 0.2 L/
min. Six samples were analyzed immediately and the rest of the samples
were divided into two groups by fifteen samples each. One group was
stored at refrigerated temperature of -25 [deg]C, and the other group
was stored at ambient temperature (approximately 23 [deg]C). These
samples were analyzed over a period of fifteen days. The results are
tabulated below.
Percent Recovery
------------------------------------------------------------------------
Day analyzed Refrigerated Ambient
------------------------------------------------------------------------
0............................... 97.4 98.7 98.9 97.4 98.7 98.9
0............................... 97.1 100.6 100.9 97.1 100.6 100.9
2............................... 95.8 96.4 95.4 95.4 96.6 96.9
5............................... 93.9 93.7 92.4 92.4 94.3 94.1
9............................... 93.6 95.5 94.6 95.2 95.6 96.6
13.............................. 94.3 95.3 93.7 91.0 95.0 94.6
15.............................. 96.8 95.8 94.2 92.9 96.3 95.9
------------------------------------------------------------------------
8.4. Desorption data.
Samples were prepared by injecting liquid benzene onto the A section
of charcoal tubes. Samples were prepared that would be equivalent to
0.5, 1.0, and 2.0 ppm for a 10 L air sample.
Percent Recovery
------------------------------------------------------------------------
Sample 0.5 ppm 1.0 ppm 2.0 ppm
------------------------------------------------------------------------
1.......................................... 99.4 98.8 99.5
2.......................................... 99.5 98.7 99.7
3.......................................... 99.2 98.6 99.8
4.......................................... 99.4 99.1 100.0
5.......................................... 99.2 99.0 99.7
6.......................................... 99.8 99.1 99.9
X=......................................... 99.4 98.9 99.8
SD=........................................ 0.22 0.21 0.18
CV=........................................ 0.0022 0.0021 0.0018
X=99.4
------------------------------------------------------------------------
8.5. Carbon disulfide.
Carbon disulfide from a number of sources was analyzed for benzene
contamination. The results are given in the following table. The benzene
contamiant can be removed with the procedures given in section 4.1.
------------------------------------------------------------------------
ppm
[micro]g equivalent
Sample Benzene/ (for 10 L
mL air
sample)
------------------------------------------------------------------------
Aldrich Lot 83017................................. 4.20 0.13
Baker Lot 720364.................................. 1.01 0.03
Baker Lot 822351.................................. 1.01 0.03
Malinkrodt Lot WEMP............................... 1.74 0.05
Malinkrodt Lot WDSJ............................... 5.65 0.18
Malinkrodt Lot WHGA............................... 2.90 0.09
Treated CS2....................................... ........ ..........
------------------------------------------------------------------------
II. OSHA Laboratory Method No. 12 for Bulk Samples
Analyte: Benzene.
Matrix: Bulk Samples.
Procedure: Bulk Samples are analyzed directly by high performance
liquid chromatography (HPLC).
Detection limits: 0.01% by volume.
1. Principle of the method.
1.1. An aliquot of the bulk sample to be analyzed is injected into a
liquid chromatograph.
1.2. The peak area for benzene is determined and compared to areas
obtained from standards.
2. Advantages and disadvantages of the method.
2.1. The analytical procedure is quick, sensitive, and reproducible.
2.2. Reanalysis of samples is possible.
2.3. Interferences can be circumvented by proper selection of HPLC
parameters.
2.4. Samples must be free of any particulates that may clog the
capillary tubing in the liquid chromatograph. This may require
distilling the sample or clarifying with a clarification kit.
3. Apparatus.
3.1. Liquid chromatograph equipped with a UV detector.
3.2. HPLC Column that will separate benzene from other components in
the bulk sample being analyzed. The column used for validation studies
was a Waters uBondapack C18, 30 cm x 3.9 mm.
3.3. A clarification kit to remove any particulates in the bulk if
necessary.
3.4. A micro-distillation apparatus to distill any samples if
necessary.
3.5. An electronic integrator or some other suitable method of
measuring peak areas.
3.6. Microliter syringes--10 [micro]L syringe and other convenient
sizes for making standards. 10 [micro]L syringe for sample injections.
3.7. Volumetric flasks, 5 mL and other convenient sizes for
preparing standards and making dilutions.
4. Reagents.
4.1. Benzene, reagent grade.
4.2. HPLC grade water, methyl alcohol, and isopropyl alcohol.
5. Collection and shipment of samples.
5.1. Samples should be transported in glass containers with Teflon-
lined caps.
[[Page 254]]
5.2. Samples should not be put in the same container used for air
samples.
6. Analysis of samples.
6.1. Sample preparation.
If necessary, the samples are distilled or clarified. Samples are
analyzed undiluted. If the benzene concentration is out of the working
range, suitable dilutions are made with isopropyl alcohol.
6.2. HPLC conditions.
The typical operating conditions for the high performance liquid
chromatograph are:
1. Mobile phase--Methyl alcohol/water, 50/50
1. Analytical wavelength--254 nm
3. Injection size--10 [micro]L
6.3. Measurement of peak area and calibration.
Peak areas are measured by an integrator or other suitable means.
The integrator is calibrated to report results % in benzene by volume.
7. Calculations.
Since the integrator is programmed to report results in % benzene by
volume in an undiluted sample, the following equation is used:
% Benzene by Volume=A x B
Where:
A=% by volume on report
B=Dilution Factor
(B=1 for undiluted sample)
8. Backup Data.
8.1. Detection limit--Bulk Samples.
The detection limit for the analytical procedure for bulk samples is
0.88 [micro]g, with a coefficient of variation of 0.019 at this level.
This amount provided a chromatographic peak that could be identifiable
in the presence of possible interferences. The detection limit date were
obtained by making 10 [micro]L injections of a 0.10% by volume standard.
------------------------------------------------------------------------
Injection Area Count
------------------------------------------------------------------------
1.................................... 45386
2.................................... 44214
3.................................... 43822 X=44040.1
4.................................... 44062 SD=852.5
6.................................... 42724 CV=0.019
------------------------------------------------------------------------
8.2. Pooled coefficient of variation--Bulk Samples.
The pooled coefficient of variation for analytical procedure was
determined by 50 [micro]L replicate injections of analytical standards.
The standards were 0.01, 0.02, 0.04, 0.10, 1.0, and 2.0% benzene by
volume.
Area count (Percent)
----------------------------------------------------------------------------------------------------------------
Injection No. 0.01 0.02 0.04 0.10 1.0 2.0
----------------------------------------------------------------------------------------------------------------
1................................................... 45386 84737 166097 448497 4395380 9339150
2................................................... 44241 84300 170832 441299 4590800 9484900
3................................................... 43822 83835 164160 443719 4593200 9557580
4................................................... 44062 84381 164445 444842 4642350 9677060
5................................................... 44006 83012 168398 442564 4646430 9766240
6................................................... 42724 81957 173002 443975 4646260
X = 44040.1 83703.6 167872 444149 4585767 9564986
SD = 852.5 1042.2 3589.8 2459.1 96839.3 166233
CV = 0.0194 0.0125 0.0213 0.0055 0.0211 0.0174
CV = 0.017
----------------------------------------------------------------------------------------------------------------
[52 FR 34562, Sept. 11, 1987, as amended at 54 FR 24334, June 7, 1989;
61 FR 5508, Feb. 13, 1996; 63 FR 1289, Jan. 8, 1998; 63 FR 20099, Apr.
23, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16673, Apr. 3, 2006; 71 FR
50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8,
2011; 77 FR 17781, Mar. 26, 2012]
Sec. 1910.1029 Coke oven emissions.
(a) Scope and application. This section applies to the control of
employee exposure to coke oven emissions, except that this section shall
not apply to working conditions with regard to which other Federal
agencies exercise statutory authority to prescribe or enforce standards
affecting occupational safety and health.
(b) Definitions. For the purpose of this section:
Authorized person means any person specifically authorized by the
employer whose duties require the person to enter a regulated area, or
any person entering such an area as a designated representative of
employees for the purpose of exercising the opportunity to observe
monitoring and measuring procedures under paragraph (n) of this section.
Beehive oven means a coke oven in which the products of
carbonization other than coke are not recovered, but are released into
the ambient air.
Coke oven means a retort in which coke is produced by the
destructive distillation or carbonization of coal.
[[Page 255]]
Coke oven battery means a structure containing a number of slot-type
coke ovens.
Coke oven emissions means the benzene-soluble fraction of total
particulate matter present during the destructive distillation or
carbonization of coal for the production of coke.
Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health, Education, and Welfare, or
his or her designee.
Emergency means any occurance such as, but not limited to, equipment
failure which is likely to, or does, result in any massive release of
coke oven emissions.
Existing coke oven battery means a battery in operation or under
construction on January 20, 1977, and which is not a rehabilitated coke
oven battery.
Rehabilitated coke oven battery means a battery which is rebuilt,
overhauled, renovated, or restored such as from the pad up, after
January 20, 1977.
Secretary means the Secretary of Labor, U.S. Department of Labor, or
his or her designee.
Stage charging means a procedure by which a predetermined volume of
coal in each larry car hopper is introduced into an oven such that no
more than two hoppers are discharging simultaneously.
Sequential charging means a procedure, usually automatically timed,
by which a predetermined volume of coal in each larry car hopper is
introduced into an oven such that no more than two hoppers commence or
finish discharging simultaneously although, at some point, all hoppers
are discharging simultaneously.
Pipeline charging means any apparatus used to introduce coal into an
oven which uses a pipe or duct permanently mounted onto an oven and
through which coal is charged.
Green plush means coke which when removed from the oven results in
emissions due to the presence of unvolatilized coal.
(c) Permissible exposure limit. The employer shall assure that no
employee in the regulated area is exposed to coke oven emissions at
concentrations greater than 150 micrograms per cubic meter of air (150
[micro]g/m\3\), averaged over any 8-hour period.
(d) Regulated areas. (1) The employer shall establish regulated
areas and shall limit access to them to authorized persons.
(2) The employer shall establish the following as regulated areas:
(i) The coke oven battery including topside and its machinery,
pushside and its machinery, coke side and its machinery, and the battery
ends; the wharf; and the screening station;
(ii) The beehive oven and its machinery.
(e) Exposure monitoring and measurement--(1) Monitoring program. (i)
Each employer who has a place of employment where coke oven emissions
are present shall monitor employees employed in the regulated area to
measure their exposure to coke oven emissions.
(ii) The employer shall obtain measurements which are representative
of each employee's exposure to coke oven emissions over an eight-hour
period. All measurements shall determine exposure without regard to the
use of respiratory protection.
(iii) The employer shall collect fullshift (for at least seven
continuous hours) personal samples, including at least one sample during
each shift for each battery and each job classification within the
regulated areas including at least the following job classifications:
(a) Lidman;
(b) Tar chaser;
(c) Larry car operator;
(d) Luterman;
(e) Machine operator, coke side;
(f) Benchman, coke side;
(g) Benchman, pusher side;
(h) Heater;
(i) Quenching car operator;
(j) Pusher machine operator;
(k) Screening station operator;
(l) Wharfman;
(m) Oven patcher;
(n) Oven repairman;
(o) Spellman; and
(p) Maintenance personnel.
(iv) The employer shall repeat the monitoring and measurements
required by this paragraph (e)(1) at least every three months.
[[Page 256]]
(2) Redetermination. Whenever there has been a production, process,
or control change which may result in new or additional exposure to coke
oven emissions, or whenever the employer has any other reason to suspect
an increase in employee exposure, the employer shall repeat the
monitoring and measurements required by paragraph (e)(1) of this section
for those employees affected by such change or increase.
(3) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each affected employee of these results either
individually in writing or by posting the results in an appropriate
location that is accessible to employees.
(ii) Whenever such results indicate that the representative employee
exposure exceeds the permissible exposure limit, the employer shall, in
such notification, inform each employee of that fact and of the
corrective action being taken to reduce exposure to or below the
permissible exposure limit.
(4) Accuracy of measurement. The employer shall use a method of
monitoring and measurement which has an accuracy (with a confidence
level of 95%) of not less than plus or minus 35% for concentrations of
coke oven emissions greater than or equal to 150 [micro]g/m\3\.
(f) Methods of compliance. The employer shall control employee
exposure to coke oven emissions by the use of engineering controls, work
practices and respiratory protection as follows:
(1) Priority of compliance methods--(i) Existing coke oven
batteries. (a) The employer shall institute the engineering and work
practice controls listed in paragraphs (f)(2), (f)(3) and (f)(4) of this
section in existing coke oven batteries at the earliest possible time,
but not later than January 20, 1980, except to the extent that the
employer can establish that such controls are not feasible. In
determining the earliest possible time for institution of engineering
and work practice controls, the requirement, effective August 27, 1971,
to implement feasible administrative or engineering controls to reduce
exposures to coal tar pitch volatiles, shall be considered. Wherever the
engineering and work practice controls which can be instituted are not
sufficient to reduce employee exposures to or below the permissible
exposure limit, the employer shall nonetheless use them to reduce
exposures to the lowest level achievable by these controls and shall
supplement them by the use of respiratory protection which complies with
the requirements of paragraph (g) of this section.
(b) The engineering and work practice controls required under
paragraphs (f)(2), (f)(3) and (f)(4) of this section are minimum
requirements generally applicable to all existing coke oven batteries.
If, after implementing all controls required by paragraphs (f)(2),
(f)(3) and (f)(4) of this section, or after January 20, 1980, whichever
is sooner, employee exposures still exceed the permissible exposure
limit, employers shall implement any other engineering and work practice
controls necessary to reduce exposure to or below the permissible
exposure limit except to the extent that the employer can establish that
such controls are not feasible. Whenever the engineering and work
practice controls which can be instituted are not sufficient to reduce
employee exposures to or below the permissible exposure limit, the
employer shall nonetheless use them to reduce exposures to the lowest
level achievable by these controls and shall supplement them by the use
of respiratory protection which complies with the requirements of
paragraph (g) of this section.
(ii) New or rehabilitated coke oven batteries. (a) The employer
shall institute the best available engineering and work practice
controls on all new or rehabilitated coke oven batteries to reduce and
maintain employee exposures at or below the permissible exposure limit,
except to the extent that the employer can establish that such controls
are not feasible. Wherever the engineering and work practice controls
which can be instituted are not sufficient to reduce employee exposures
to or below the permissible exposure limit, the employer shall
nonetheless use them to reduce exposures to the lowest level achievable
by these controls and shall supplement them by the use of respiratory
protection which
[[Page 257]]
complies with the requirements of paragraph (g) of this section.
(b) If, after implementing all the engineering and work practice
controls required by paragraph (f)(1)(ii)(a) of this section, employee
exposures still exceed the permissible exposure limit, the employer
shall implement any other engineering and work practice controls
necessary to reduce exposure to or below the permissible exposure limit
except to the extent that the employer can establish that such controls
are not feasible. Wherever the engineering and work practice controls
which can be instituted are not sufficient to reduce employee exposures
to or below the permissible exposure limit, the employer shall
nonetheless use them to reduce exposures to the lowest level achievable
by these controls and shall supplement them by the use of respiratory
protection which complies with the requirements of paragraph (g) of this
section.
(iii) Beehive ovens. (a) The employer shall institute engineering
and work practice controls on all beehive ovens at the earliest possible
time to reduce and maintain employee exposures at or below the
permissible exposure limit, except to the extent that the employer can
establish that such controls are not feasible. In determining the
earliest possible time for institution of engineering and work practice
controls, the requirement, effective August 27, 1971, to implement
feasible administrative or engineering controls to reduce exposures to
coal tar pitch volatiles, shall be considered. Wherever the engineering
and work practice controls which can be instituted are not sufficient to
reduce employee exposures to or below the permissible exposure limit,
the employer shall nonetheless use them to reduce exposures to the
lowest level achievable by these controls and shall supplement them by
the use of respiratory protection which complies with the requirements
of paragraph (g) of this section.
(b) If, after implementing all engineering and work practice
controls required by paragraph (f)(1)(iii)(a) of this section, employee
exposures still exceed the permissible exposure limit, the employer
shall implement any other engineering and work practice controls
necessary to reduce exposures to or below the permissible exposure limit
except to the extent that the employer can establish that such controls
are not feasible. Whenever the engineering and work practice controls
which can be instituted are not sufficient to reduce employee exposures
to or below the permissible exposure limit, the employer shall
nonetheless use them to reduce exposures to the lowest level achievable
by these controls and shall supplement them by the use of respiratory
protection which complies with the requirements of paragraph (g) of this
section.
(2) Engineering controls--(i) Charging. The employer shall equip and
operate existing coke oven batteries with all of the following
engineering controls to control coke oven emissions during charging
operations:
(a) One of the following methods of charging:
(1) Stage charging as described in paragraph (f)(3)(i)(b) of this
section; or
(2) Sequential charging as described in paragraph (f)(3)(i)(b) of
this section except that paragraph (f)(3)(i)(b)(3)(iv) of this section
does not apply to sequential charging; or
(3) Pipeline charging or other forms of enclosed charging in
accordance with paragraph (f)(2)(i) of this section, except that
paragraphs (f)(2)(i)(b), (d), (e), (f) and (h) of this section do not
apply;
(b) Drafting from two or more points in the oven being charged,
through the use of double collector mains, or a fixed or moveable jumper
pipe system to another oven, to effectively remove the gases from the
oven to the collector mains;
(c) Aspiration systems designed and operated to provide sufficient
negative pressure and flow volume to effectively move the gases evolved
during charging into the collector mains, including sufficient steam
pressure, and steam jets of sufficient diameter;
(d) Mechanical volumetric controls on each larry car hopper to
provide the proper amount of coal to be charged through each charging
hole so that the tunnel head will be sufficient to permit the gases to
move from the oven into the collector mains;
[[Page 258]]
(e) Devices to facilitate the rapid and continuous flow of coal into
the oven being charged, such as stainless steel liners, coal vibrators
or pneumatic shells;
(f) Individually operated larry car drop sleeves and slide gates
designed and maintained so that the gases are effectively removed from
the oven into the collector mains;
(g) Mechanized gooseneck and standpipe cleaners;
(h) Air seals on the pusher machine leveler bars to control air
infiltration during charging; and
(i) Roof carbon cutters or a compressed air system or both on the
pusher machine rams to remove roof carbon.
(ii) Coking. The employer shall equip and operate existing coke oven
batteries with all of the following engineering controls to control coke
oven emissions during coking operations;
(a) A pressure control system on each battery to obtain uniform
collector main pressure;
(b) Ready access to door repair facilities capable of prompt and
efficient repair of doors, door sealing edges and all door parts;
(c) An adequate number of spare doors available for replacement
purposes;
(d) Chuck door gaskets to control chuck door emissions until such
door is repaired, or replaced; and
(e) Heat shields on door machines.
(3) Work practice controls--(i) Charging. The employer shall operate
existing coke oven batteries with all of the following work practices to
control coke oven emissions during the charging operation:
(a) Establishment and implementation of a detailed, written
inspection and cleaning procedure for each battery consisting of at
least the following elements:
(1) Prompt and effective repair or replacement of all engineering
controls;
(2) Inspection and cleaning of goosenecks and standpipes prior to
each charge to a specified minimum diameter sufficient to effectively
move the evolved gases from the oven to the collector mains;
(3) Inspection for roof carbon build-up prior to each charge and
removal of roof carbon as necessary to provide an adequate gas channel
so that the gases are effectively moved from the oven into the collector
mains;
(4) Inspection of the steam aspiration system prior to each charge
so that sufficient pressure and volume is maintained to effectively move
the gases from the oven to the collector mains;
(5) Inspection of steam nozzles and liquor sprays prior to each
charge and cleaning as necessary so that the steam nozzles and liquor
sprays are clean;
(6) Inspection of standpipe caps prior to each charge and cleaning
and luting or both as necessary so that the gases are effectively moved
from the oven to the collector mains; and
(7) Inspection of charging holes and lids for cracks, warpage and
other defects prior to each charge and removal of carbon to prevent
emissions, and application of luting material to standpipe and charging
hole lids where necessary to obtain a proper seal.
(b) Establishment and implementation of a detailed written charging
procedure, designed and operated to eliminate emissions during charging
for each battery, consisting of at least the following elements:
(1) Larry car hoppers filled with coal to a predetermined level in
accordance with the mechanical volumetric controls required under
paragraph (f)(2)(i)(d) of this section so as to maintain a sufficient
gas passage in the oven to be charged;
(2) The larry car aligned over the oven to be charged, so that the
drop sleeves fit tightly over the charging holes; and
(3) The oven charged in accordance with the following sequence of
requirements:
(i) The aspiration system turned on;
(ii) Coal charged through the outermost hoppers, either individually
or together depending on the capacity of the aspiration system to
collect the gases involved;
(iii) The charging holes used under paragraph (f)(3)(i)(b)(3)(ii) of
this section relidded or otherwise sealed off to prevent leakage of coke
oven emissions;
[[Page 259]]
(iv) If four hoppers are used, the third hopper discharged and
relidded or otherwise sealed off to prevent leakage of coke oven
emissions;
(v) The final hopper discharged until the gas channel at the top of
the oven is blocked and then the chuck door opened and the coal leveled;
(vi) When the coal from the final hopper is discharged and the
leveling operation complete, the charging hole relidded or otherwise
sealed off to prevent leakage of coke oven emissions; and
(vii) The aspiration system turned off only after the charging holes
have been closed.
(c) Establishment and implementation of a detailed written charging
procedure, designed and operated to eliminate emissions during charging
of each pipeline or enclosed charged battery.
(ii) Coking. The employer shall operate existing coke oven batteries
pursuant to a detailed written procedure established and implemented for
the control of coke oven emissions during coking, consisting of at least
the following elements:
(a) Checking oven back pressure controls to maintain uniform
pressure conditions in the collecting main;
(b) Repair, replacement and adjustment of oven doors and chuck doors
and replacement of door jambs so as to provide a continuous metal-to-
metal fit;
(c) Cleaning of oven doors, chuck doors and door jambs each coking
cycle so as to provide an effective seal;
(d) An inspection system and corrective action program to control
door emissions to the maximum extent possible; and
(e) Luting of doors that are sealed by luting each coking cycle and
reluting, replacing or adjusting as necessary to control leakage.
(iii) Pushing. The employer shall operate existing coke oven
batteries with the following work practices to control coke oven
emissions during pushing operations:
(a) Coke and coal spillage quenched as soon as practicable and not
shoveled into a heated oven; and
(b) A detailed written procedure for each battery established and
implemented for the control of emissions during pushing consisting of
the following elements:
(1) Dampering off the ovens and removal of charging hole lids to
effectively control coke oven emissions during the push;
(2) Heating of the coal charge uniformly for a sufficient period so
as to obtain proper coking including preventing green pushes;
(3) Prevention of green pushes to the maximum extent possible;
(4) Inspection, adjustment and correction of heating flue
temperatures and defective flues at least weekly and after any green
push, so as to prevent green pushes;
(5) Cleaning of heating flues and related equipment to prevent green
pushes, at least weekly and after any green push.
(iv) Maintenance and repair. The employer shall operate existing
coke oven batteries pursuant to a detailed written procedure of
maintenance and repair established and implemented for the effective
control of coke oven emissions consisting of the following elements:
(a) Regular inspection of all controls, including goosenecks,
standpipes, standpipe caps, charging hold lids and castings, jumper
pipes and air seals for cracks, misalignment or other defects and prompt
implementation of the necessary repairs as soon as possible;
(b) Maintaining the regulated area in a neat, orderly condition free
of coal and coke spillage and debris;
(c) Regular inspection of the damper system, aspiration system and
collector main for cracks or leakage, and prompt implementation of the
necessary repairs;
(d) Regular inspection of the heating system and prompt
implementation of the necessary repairs;
(e) Prevention of miscellaneous fugitive topside emissions;
(f) Regular inspection and patching of oven brickwork;
(g) Maintenance of battery equipment and controls in good working
order;
(h) Maintenance and repair of coke oven doors, chuck doors, door
jambs and seals; and
[[Page 260]]
(i) Repairs instituted and completed as soon as possible, including
temporary repair measures instituted and completed where necessary,
including but not limited to:
(1) Prevention of miscellaneous fugitive topside emissions; and
(2) Chuck door gaskets, which shall be installed prior to the start
of the next coking cycle.
(4) Filtered air. (i) The employer shall provided positive-pressure,
temperature controlled filtered air for larry car, pusher machine, door
machine, and quench car cabs.
(ii) The employer shall provide standby pulpits on the battery
topside, at the wharf, and at ther screening station, equipped with
positive-pressure, temperature controlled filtered air.
(5) Emergencies. Whenever an emergency occurs, the next coking cycle
may not begin until the cause of the emergency is determined and
corrected, unless the employer can establish that it is necessary to
initiate the next coking cycle in order to determine the cause of the
emergency.
(6) Compliance program. (i) Each employer shall establish and
implement a written program to reduce exposures solely by means of the
engineering and work practice controls required in paragraph (f) of this
section.
(ii) The written program shall include at least the following:
(a) A description of each coke oven operation by battery, including
work force and operating crew, coking time, operating procedures and
maintenance practices;
(b) Engineering plans and other studies used to determine the
controls for the coke battery;
(c) A report of the technology considered in meeting the permissible
exposure limit;
(d) Monitoring data obtained in accordance with paragraph (e) of
this section;
(e) A detailed schedule for the implementation of the engineering
and work practice controls required in paragraph (f) of this section;
and
(f) Other relevant information.
(iii) If, after implementing all controls required by paragraph
(f)(2)-(f)(4) of this section, or after January 20, 1980, whichever is
sooner, or after completion of a new or rehabilitated battery the
permissible exposure limit is still exceeded, the employer shall develop
a detailed written program and schedule for the implementation of any
additional engineering controls and work practices necessary to reduce
exposure to or below the permissible exposure limit.
(iv) Written plans for such programs shall be submitted, upon
request, to the Secretary and the Director, and shall be available at
the worksite for examination and copying by the Secretary, the Director,
and the authorized employee representative. The plans required under
paragraph (f)(6) of this section shall be revised and updated at least
annually to reflect the current status of the program.
(7) Training in compliance procedures. The employer shall
incorporate all written procedures and schedules required under this
paragraph (f) in the information and training program required under
paragraph (k) of this section and, where appropriate, post in the
regulated area.
(g) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Work operations, such as maintenance and repair activity, for
which engineering and work-practice controls are technologically not
feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the permissible exposure limit.
(iv) Emergencies.
(2) Respirator program. The employer must implement a respiratory
protection program in accordance withSec. 1910.134(b) through (d)
(except (d)(1)(iii)), and (f) through (m), which covers each employee
required by this section to use a respirator.
(3) Respirator selection. Employers must select, and provide to
employees, the appropriate respirators specified in paragraph
(d)(3)(i)(A) of 29 CFR
[[Page 261]]
1910.134; however, employers may use a filtering facepiece respirator
only when it functions as a filter respirator for coke oven emissions
particulates.
(h) Protective clothing and equipment--(1) Provision and use. The
employer shall provide and assure the use of appropriate protective
clothing and equipment, such as but not limited to:
(i) Flame resistant jacket and pants;
(ii) Flame resistant gloves;
(iii) Face shields or vented goggles which comply withSec.
1910.133(a)(2) of this part;
(iv) Footwear providing insulation from hot surfaces for footwear;
(v) Safety shoes which comply withSec. 1910.136 of this part; and
(vi) Protective helmets which comply withSec. 1910.135 of this
part.
(2) Cleaning and replacement. (i) The employer shall provide the
protective clothing required by paragraphs (h)(1) (i) and (ii) of this
section in a clean and dry condition at least weekly.
(ii) The employer shall clean, launder, or dispose of protective
clothing required by paragraphs (h)(1) (i) and (ii) of this section.
(iii) The employer shall repair or replace the protective clothing
and equipment as needed to maintain their effectiveness.
(iv) The employer shall assure that all protective clothing is
removed at the completion of a work shift only in change rooms
prescribed in paragraph (i)(1) of this section.
(v) The employer shall assure that contaminated protective clothing
which is to be cleaned, laundered, or disposed of, is placed in a
closable container in the change room.
(vi) The employer shall inform any person who cleans or launders
protective clothing required by this section, of the potentially harmful
effects of exposure to coke oven emissions.
(i) Hygiene facilities and practices--(1) Change rooms. The employer
shall provide clean change rooms equipped with storage facilities for
street clothes and separate storage facilities for protective clothing
and equipment whenever employees are required to wear protective
clothing and equipment in accordance with paragraph (h)(1) of this
section.
(2) Showers. (i) The employer shall assure that employees working in
the regulated area shower at the end of the work shift.
(ii) The employer shall provide shower facilities in accordance with
Sec. 1910.141(d)(3) of this part.
(3) Lunchrooms. The employer shall provide lunchroom facilities
which have a temperature controlled, positive pressure, filtered air
supply, and which are readily accessible to employees working in the
regulated area.
(4) Lavatories. (i) The employer shall assure that employees working
in the regulated area wash their hands and face prior to eating.
(ii) The employer shall provide lavatory facilities in accordance
withSec. 1910.141(d) (1) and (2) of this part.
(5) Prohibition of activities in the regulated area. (i) The
employer shall assure that in the regulated area, food or beverages are
not present or consumed, smoking products are not present or used, and
cosmetics are not applied, except that these activities may be conducted
in the lunchrooms, change rooms and showers required under paragraphs
(i)(1)-(i)(3) of this section.
(ii) Drinking water may be consumed in the regulated area.
(j) Medical surveillance--(1) General requirements. (i) Each
employer shall institute a medical surveillance program for all
employees who are employed in a regulated area at least 30 days per
year.
(ii) This program shall provide each employee covered under
paragraph (j)(1)(i) of this section with an opportunity for medical
examinations in accordance with this paragraph (j).
(iii) The employer shall inform any employee who refuses any
required medical examination of the possible health consequences of such
refusal and shall obtain a signed statement from the employee indicating
that the employee understands the risk involved in the refusal to be
examined.
(iv) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician, and are provided without cost to the employee.
(2) Initial examinations. At the time of initial assignment to a
regulated area
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or upon the institution of the medical surveillance program, the
employer shall provide a medical examination for employees covered under
paragraph (j)(1)(i) of this section including at least the following
elements:
(i) A work history and medical history which shall include smoking
history and the presence and degree of respiratory symptoms, such as
breathlessness, cough, sputum production, and wheezing;
(ii) A standard posterior-anterior chest x-ray;
(iii) Pulmonary function tests including forced vital capacity (FVC)
and forced expiratory volume at one second (FEV 1.0) with recording of
type of equipment used;
(iv) Weight;
(v) A skin examination;
(vi) Urinalysis for sugar, albumin, and hematuria; and
(vii) A urinary cytology examination.
(3) Periodic examinations. (i) The employer shall provide the
examinations specified in paragraphs (j)(2) (i)-(vi) of this section at
least annually for employees covered under paragraph (j)(1)(i) of this
section.
(ii) The employer must provide the examinations specified in
paragraphs (j)(2)(i) through (j)(2)(vii) of this section at least
annually for employees 45 years of age or older or with five (5) or more
years employment in the regulated area.
(iii) Whenever an employee who is 45 years of age or older or with
five (5) or more years employment in a regulated area transfers or is
transferred from employment in a regulated area, the employer must
continue to provide the examinations specified in paragraphs (j)(2)(i)
through (j)(2)(vii) of this section at least annually as long as that
employee is employed by the same employer or a successor employer.
(iv) Whenever an employee has not taken the examinations specified
in paragraphs (j)(3) (i)-(iii) of this section with the six (6) months
preceding the termination of employment the employer shall provide such
examinations to the employee upon termination of employment.
(4) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this regulation and its Appendixes;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's exposure level or estimated exposure level;
(iv) A description of any personal protective equipment used or to
be used; and
(v) Information from previous medical examinations of the affected
employee which is not readily available to the examining physician.
(5) Physician's written opinion. (i) The employer shall obtain a
written opinion from the examining physician which shall include:
(a) The results of the medical examinations;
(b) The physician's opinion as to whether the employee has any
detected medical conditions which would place the employee at increased
risk of material impairment of the employee's health from exposure to
coke oven emissions;
(c) Any recommended limitations upon the employee's exposure to coke
oven emissions or upon the use of protective clothing or equipment such
as respirators; and
(d) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
which require further explanation or treatment.
(ii) The employer shall instruct the physician not to reveal in the
written opinion specific findings or diagnoses unrelated to occupational
exposure.
(iii) The employer shall provide a copy of the written opinion to
the affected employee.
(k) Employee information and training--(1) Training program. (i) The
employer shall train each employee who is employed in a regulated area
in accordance with the requirements of this section. The employer shall
institute a training program and ensure employee participation in the
program.
(ii) The training program shall be provided as of January 27, 1977
for employees who are employed in the regulated area at that time or at
the time
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of initial assignment to a regulated area.
(iii) The training program shall be provided at least annually for
all employees who are employed in the regulated area, except that
training regarding the occupational safety and health hazards associated
with exposure to coke oven emissions and the purpose, proper use, and
limitations of respiratory protective devices shall be provided at least
quarterly until January 20, 1978.
(iv) The training program shall include informing each employee of:
(a) The information contained in the substance information sheet for
coke oven emissions (Appendix A);
(b) The purpose, proper use, and limitations of respiratory
protective devices required in accordance with paragraph (g) of this
section;
(c) The purpose for and a description of the medical surveillance
program required by paragraph (j) of this section including information
on the occupational safety and health hazards associated with exposure
to coke oven emissions;
(d) A review of all written procedures and schedules required under
paragraph (f) of this section; and
(e) A review of this standard.
(2) Access to training materials. (i) The employer shall make a copy
of this standard and its appendixes readily available to all employees
who are employed in the regulated area.
(ii) The employer shall provide upon request all materials relating
to the employee information and training program to the Secretary and
the Director.
(l) Communication of hazards--(1) Hazard communication--general. The
employer shall include coke oven emissions in the program established to
comply with the Hazard Communication Standard (HCS) (Sec. 1910.1200).
The employer shall ensure that each employee has access to labels on
containers of chemicals and substances associated with coke oven
processes and to safety data sheets, and is trained in accordance with
the provisions of HCS and paragraph (k) of this section. The employer
shall ensure that at least the following hazard is addressed: Cancer.
(2) Signs. (i) The employer shall post signs in the regulated area
bearing the legend:
DANGER
COKE OVEN EMISSIONS
MAY CAUSE CANCER
DO NOT EAT, DRINK OR SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(ii) In addition, the employer shall post signs in the areas where
the permissible exposure limit is exceeded bearing the legend:
WEAR RESPIRATORY PROTECTION IN THIS AREA
(iii) The employer shall ensure that no statement appears on or near
any sign required by this paragraph (l) which contradicts or detracts
from the effects of the required sign.
(iv) The employer shall ensure that signs required by this paragraph
(l)(2) are illuminated and cleaned as necessary so that the legend is
readily visible.
(v) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (l)(2)(i) of this section:
DANGER
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
NO SMOKING OR EATING
(vi) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (l)(2)(ii) of this section:
DANGER
RESPIRATOR REQUIRED
(3) Labels. (i) The employer shall ensure that labels of containers
of contaminated protective clothing and equipment include the following
information:
CONTAMINATED WITH COKE EMISSIONS
MAY CAUSE CANCER
DO NOT REMOVE DUST BY BLOWING OR SHAKING
(ii) Prior to June 1, 2015, employers may include the following
information on contaminated protective clothing and equipment in lieu of
the labeling requirements in paragraph (l)(3)(i) of this section:
CAUTION
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CLOTHING CONTAMINATED WITH COKE EMISSIONS
DO NOT REMOVE DUST BY BLOWING OR SHAKING
(m) Recordkeeping--(1) Exposure measurements. The employer shall
establish and maintain an accurate record of all measurements taken to
monitor employee exposure to coke oven emissions required in paragraph
(e) of this section.
(i) This record shall include:
(a) Name, social security number, and job classification of the
employees monitored;
(b) The date(s), number, duration and results of each of the samples
taken, including a description of the sampling procedure used to
determine representative employee exposure where applicable;
(c) The type of respiratory protective devices worn, if any;
(d) A description of the sampling and analytical methods used and
evidence of their accuracy; and
(e) The environmental variables that could affect the measurement of
employee exposure.
(ii) The employer shall maintain this record for at lest 40 years or
for the duration of employment plus 20 years, whichever is longer.
(2) Medical surveillance. The employer shall establish and maintain
an accurate record for each employee subject to medical surveillance as
required by paragraph (j) of this section.
(i) The record shall include:
(a) The name, social security number, and description of duties of
the employee;
(b) A copy of the physician's written opinion;
(c) The signed statement of any refusal to take a medical
examination under paragraph (j)(1)(ii) of this section; and
(d) Any employee medical complaints related to exposure to coke oven
emissions.
(ii) The employer shall keep, or assure that the examining physician
keeps, the following medical records:
(a) A copy of the medical examination results including medical and
work history required under paragraph (j)(2) of this section;
(b) A description of the laboratory procedures used and a copy of
any standards or guidelines used to interpret the test results;
(c) The initial x-ray;
(d) The x-rays for the most recent five (5) years;
(e) Any x-ray with a demonstrated abnormality and all subsequent x-
rays;
(f) The initial cytologic examination slide and written description;
(g) The cytologic examination slide and written description for the
most recent 10 years; and
(h) Any cytologic examination slides with demonstrated atypia, if
such atypia persists for 3 years, and all subsequent slides and written
descriptions.
(iii) The employer shall maintain medical records required under
paragraph (m)(2) of this section for at least 40 years, or for the
duration of employment plus 20 years, whichever is longer.
(3) Availability. (i) The employer shall make available upon request
all records required to be maintained by paragraph (m) of this section
to the Secretary and the Director for examination and copying.
(ii) Employee exposure measurement records and employee medical
records required by this paragraph shall be provided upon request to
employees, designated representatives, and the Assistant Secretary in
accordance with 29 CFR 1910.1020(a)-(e) and (g)-(i).
(4) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by paragraph (m) of this section.
(ii) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.1020(h).
(n) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees or their representatives an
opportunity to observe any measuring or monitoring of employee exposure
to coke oven emissions conducted pursuant to paragraph (e) of this
section.
(2) Observation procedures. (i) Whenever observation of the
measuring or monitoring of employee exposure to coke oven emissions
requires entry
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into an area where the ues of protective clothing or equipment is
required, the employer shall provide the observer with and assure the
use of such equipment and shall require the observer to comply with all
other applicable safety and health procedures.
(ii) Without interfering with the measurement, observers shall be
entitled to:
(a) An Explanation of the measurement procedures;
(b) Observe all steps related to the measurement of coke oven
emissions performed at the place of exposure; and
(c) Record the results obtained.
(o) [Reserved]
(p) Appendices. The information contained in the appendixes to this
section is not intended, by itself, to create any additional obligations
not otherwise imposed or to detract from any existing obligation.
Appendix A toSec. 1910.1029--Coke Oven Emissions Substance Information
Sheet
i. Substance Identification
A. Substance: Coke Oven Emissions
B. Definition: The benzene-soluble fraction of total particulate
matter present during the destructive distillation or carbonization of
coal for the production of coke.
C. Permissible Exposure Limit: 150 micrograms per cubic meter of air
determined as an average over an 8-hour period.
D. Regulated areas: Only employees authorized by your employer
should enter a regulated area. The employer is required to designate the
following areas as regulated areas: the coke oven battery, including
topside and its machinery, pushside and its machinery, cokeside and its
machinery, and the battery ends; the screening station; and the wharf;
and the beehive ovens and their machinery.
ii. Health Hazard Data
Exposure to coke oven emissions is a cause of lung cancer, and
kidney cancer, in humans. Although there have not been an excess number
of skin cancer cases in humans, repeated skin contact with coke oven
emissions should be avoided.
iii. Protective Clothing and Equipment
A. Respirators: Respirators will be provided by your employer for
routine use if your employer is in the process of implementing
engineering and work practice controls or where engineering and work
practice controls are not feasible or insufficient to reduce exposure to
or below the PEL. You must wear respirators for non-routine activities
or in emergency situations where you are likely to be exposed to levels
of coke oven emissions in excess of the permissible exposure limit.
Until January 20, 1978, the routine wearing of respirators is voluntary.
Until that date, if you choose not to wear a respirator you do not have
to do so. You must still have your respirator with you and you must
still wear it if you are near visible emissions. Since how well your
respirator fits your face is very important, your employer is required
to conduct fit tests to make sure the respirator seals properly when you
wear it. These tests are simple and rapid and will be explained to you
during your training sessions.
B. Protective clothing: Your employer is required to provide, and
you must wear, appropriate, clean, protective clothing and equipment to
protect your body from repeated skin contact with coke oven emissions
and from the heat generated during the coking process. This clothing
should include such items as jacket and pants and flame resistant
gloves. Protective equipment should include face shield or vented
goggles, protective helmets and safety shoes, insulated from hot
surfaces where appropriate.
iv. Hygiene Facilities and Practices
You must not eat, drink, smoke, chew gum or tobacco, or apply
cosmetics in the regulated area, except that drinking water is
permitted. Your employer is required to provide lunchrooms and other
areas for these purposes.
Your employer is required to provide showers, washing facilities,
and change rooms. If you work in a regulated area, you must wash your
face, and hands before eating. You must shower at the end of the work
shift. Do not take used protective clothing out of the change rooms
without your employer's permission. Your employer is required to provide
for laundering or cleaning of your protective clothing.
v. Signs and Labels
Your employer is required to post warning signs and labels for your
protection. Signs must be posted in regulated areas. The signs must warn
that a cancer hazard is present, that only authorized employees may
enter the area, and that no smoking or eating is allowed. In regulated
areas where coke oven emissions are above the permissible exposure
limit, the signs should also warn that respirators must be worn.
vi. Medical Examinations
If you work in a regulated area at least 30 days per year, your
employer is required to provide you with a medical examination every
year. The medical examination must
[[Page 266]]
include a medical history, a chest x-ray, pulmonary function test,
weight comparison, skin examination, a urinalysis, and a urine cytology
exam for early detection of urinary cancer. The urine cytology exam is
only included in the initial exam until you are either 45 years or
older, or have 5 or more years employment in the regulated areas when
the medical exams including this test, but excepting the x-ray exam, are
to be given every six months; under these conditions, you are to be
given an x-ray exam at least once a year. The examining physician will
provide a written opinion to your employer containing the results of the
medical exams. You should also receive a copy of this opinion.
vii. Observation of Monitoring
Your employer is required to monitor your exposure to coke oven
emissions and you are entitled to observe the monitoring procedure. You
are entitled to receive an explanation of the measurement procedure,
observe the steps taken in the measurement procedure, and to record the
results obtained. When the monitoring procedure is taking place in an
area where respirators or personal protective clothing and equipment are
required to be worn, you must also be provided with and must wear the
protective clothing and equipment.
viii. Access to Records
You or your representative are entitled to records of your exposure
to coke oven emissions upon request to your employer. Your medical
examination records can be furnished to your physician upon request to
your employer.
ix. Training and Education
Additional information on all of these items plus training as to
hazards of coke oven emissions and the engineering and work practice
controls associated with your job will also be provided by your
employer.
Appendix B toSec. 1910.1029--Industrial Hygiene and Medical
Surveillance Guidelines
i. industrial hygiene guidelines
A. Sampling (Benzene-Soluble Fraction Total Particulate Matter).
Samples collected should be full shift (at least 7-hour) samples.
Sampling should be done using a personal sampling pump with pulsation
damper at a flow rate of 2 liters per minute. Samples should be
collected on 0.8 micrometer pore size silver membrane filters (37 mm
diameter) preceded by Gelman glass fiber type A-E filters encased in
three-piece plastic (polystyrene) field monitor cassettes. The cassette
face cap should be on and the plug removed. The rotameter should be
checked every hour to ensure that proper flow rates are maintained.
A minimum of three full-shift samples should be collected for each
job classification on each battery, at least one from each shift. If
disparate results are obtained for particular job classification,
sampling should be repeated. It is advisable to sample each shift on
more than one day to account for environmental variables (wind,
precipitation, etc.) which may affect sampling. Differences in exposures
among different work shifts may indicate a need to improve work
practices on a particular shift. Sampling results from different shifts
for each job classification should not be averaged. Multiple samples
from same shift on each battery may be used to calculate an average
exposure for a particular job classification.
B. Analysis.
1. All extraction glassware is cleaned with dichromic acid cleaning
solution, rinsed with tap water, then dionized water, acetone, and
allowed to dry completely. The glassware is rinsed with nanograde
benzene before use. The Teflon cups are cleaned with benzene then with
acetone.
2. Pre-weigh the 2 ml Teflon cups to one hundredth of a milligram
(0.01 mg) on an autobalance AD 2 Tare weight of the cups is about 50 mg.
3. Place the silver membrane filter and glass fiber filter into a 15
ml test tube.
4. Extract with 5 ml of benzene for five minutes in an ultrasonic
cleaner.
5. Filter the extract in 15 ml medium glass fritted funnels.
6. Rinse test tube and filters with two 1.5 ml aliquots of benzene
and filter through the fritted glass funnel.
7. Collect the extract and two rinses in a 10 ml Kontes graduated
evaporative concentrator.
8. Evaporate down to 1 ml while rinsing the sides with benzene.
9. Pipet 0.5 ml into the Teflon cup and evaporate to dryness in a
vacuum oven at 40 [deg]C for 3 hours.
10. Weigh the Teflon cup and the weight gain is due to the benzene
soluble residue in half the Sample.
ii. medical surveillance guidelines
A. General. The minimum requirements for the medical examination for
coke oven workers are given in paragraph (j) of the standard. The
initial examination is to be provided to all coke oven workers who work
at least 30 days in the regulated area. The examination includes a
14 x 17 posterior-anterior chest x-ray reading,
pulmonary function tests (FVC and FEV 1.0), weight, urinalysis, skin
examination, and a urinary cytologic examination. These tests are needed
to serve as the baseline for comparing the employee's future test
results. Periodic exams include all the elements of the initial
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exam, except that the urine cytologic test is to be performed only on
those employees who are 45 years or older or who have worked for 5 or
more years in the regulated area; periodic exams, with the exception of
x-rays, are to be performed semiannually for this group instead of
annually; for this group, x-rays will continue to be given at least
annually. The examination contents are minimum requirements; additional
tests such as lateral and oblique x-rays or additional pulmonary
function tests may be performed if deemed necessary.
B. Pulmonary function tests.
Pulmonary function tests should be performed in a manner which
minimizes subject and operator bias. There has been shown to be learning
effects with regard to the results obtained from certain tests, such as
FEV 1.0. Best results can be obtained by multiple trials for each
subject. The best of three trials or the average of the last three of
five trials may be used in obtaining reliable results. The type of
equipment used (manufacturer, model, etc.) should be recorded with the
results as reliability and accuracy varies and such information may be
important in the evaluation of test results. Care should be exercised to
obtain the best possible testing equipment.
[39 FR 23502, June 27, 1974, 41 FR 46784, Oct. 22, 1976, as amended at
42 FR 3304, Jan. 18, 1977; 45 FR 35283, May 23, 1980; 50 FR 37353,
37354, Sept. 13, 1985; 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13,
1996; 63 FR 1290, Jan. 8, 1998; 63 FR 33468, June 18, 1998; 70 FR 1142,
Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24,
2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77 FR
17782, Mar. 26, 2012]
Sec. 1910.1030 Bloodborne pathogens.
(a) Scope and Application. This section applies to all occupational
exposure to blood or other potentially infectious materials as defined
by paragraph (b) of this section.
(b) Definitions. For purposes of this section, the following shall
apply:
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, or designated representative.
Blood means human blood, human blood components, and products made
from human blood.
Bloodborne Pathogens means pathogenic microorganisms that are
present in human blood and can cause disease in humans. These pathogens
include, but are not limited to, hepatitis B virus (HBV) and human
immunodeficiency virus (HIV).
Clinical Laboratory means a workplace where diagnostic or other
screening procedures are performed on blood or other potentially
infectious materials.
Contaminated means the presence or the reasonably anticipated
presence of blood or other potentially infectious materials on an item
or surface.
Contaminated Laundry means laundry which has been soiled with blood
or other potentially infectious materials or may contain sharps.
Contaminated Sharps means any contaminated object that can penetrate
the skin including, but not limited to, needles, scalpels, broken glass,
broken capillary tubes, and exposed ends of dental wires.
Decontamination means the use of physical or chemical means to
remove, inactivate, or destroy bloodborne pathogens on a surface or item
to the point where they are no longer capable of transmitting infectious
particles and the surface or item is rendered safe for handling, use, or
disposal.
Director means the Director of the National Institute for
Occupational Safety and Health, U.S. Department of Health and Human
Services, or designated representative.
Engineering controls means controls (e.g., sharps disposal
containers, self-sheathing needles, safer medical devices, such as
sharps with engineered sharps injury protections and needleless systems)
that isolate or remove the bloodborne pathogens hazard from the
workplace.
Exposure Incident means a specific eye, mouth, other mucous
membrane, non-intact skin, or parenteral contact with blood or other
potentially infectious materials that results from the performance of an
employee's duties.
Handwashing facilities means a facility providing an adequate supply
of running potable water, soap, and single-use towels or air-drying
machines.
Licensed Healthcare Professional is a person whose legally permitted
scope of practice allows him or her to independently perform the
activities required by paragraph (f) Hepatitis B Vaccination and Post-
exposure Evaluation and Follow-up.
HBV means hepatitis B virus.
[[Page 268]]
HIV means human immunodeficiency virus.
Needleless systems means a device that does not use needles for:
(1) The collection of bodily fluids or withdrawal of body fluids
after initial venous or arterial access is established;
(2) The administration of medication or fluids; or
(3) Any other procedure involving the potential for occupational
exposure to bloodborne pathogens due to percutaneous injuries from
contaminated sharps.
Occupational Exposure means reasonably anticipated skin, eye, mucous
membrane, or parenteral contact with blood or other potentially
infectious materials that may result from the performance of an
employee's duties.
Other Potentially Infectious Materials means
(1) The following human body fluids: semen, vaginal secretions,
cerebrospinal fluid, synovial fluid, pleural fluid, pericardial fluid,
peritoneal fluid, amniotic fluid, saliva in dental procedures, any body
fluid that is visibly contaminated with blood, and all body fluids in
situations where it is difficult or impossible to differentiate between
body fluids;
(2) Any unfixed tissue or organ (other than intact skin) from a
human (living or dead); and
(3) HIV-containing cell or tissue cultures, organ cultures, and HIV-
or HBV-containing culture medium or other solutions; and blood, organs,
or other tissues from experimental animals infected with HIV or HBV.
Parenteral means piercing mucous membranes or the skin barrier
through such events as needlesticks, human bites, cuts, and abrasions.
Personal Protective Equipment is specialized clothing or equipment
worn by an employee for protection against a hazard. General work
clothes (e.g., uniforms, pants, shirts or blouses) not intended to
function as protection against a hazard are not considered to be
personal protective equipment.
Production Facility means a facility engaged in industrial-scale,
large-volume or high concentration production of HIV or HBV.
Regulated Waste means liquid or semi-liquid blood or other
potentially infectious materials; contaminated items that would release
blood or other potentially infectious materials in a liquid or semi-
liquid state if compressed; items that are caked with dried blood or
other potentially infectious materials and are capable of releasing
these materials during handling; contaminated sharps; and pathological
and microbiological wastes containing blood or other potentially
infectious materials.
Research Laboratory means a laboratory producing or using research-
laboratory-scale amounts of HIV or HBV. Research laboratories may
produce high concentrations of HIV or HBV but not in the volume found in
production facilities.
Sharps with engineered sharps injury protections means a nonneedle
sharp or a needle device used for withdrawing body fluids, accessing a
vein or artery, or administering medications or other fluids, with a
built-in safety feature or mechanism that effectively reduces the risk
of an exposure incident.
Source Individual means any individual, living or dead, whose blood
or other potentially infectious materials may be a source of
occupational exposure to the employee. Examples include, but are not
limited to, hospital and clinic patients; clients in institutions for
the developmentally disabled; trauma victims; clients of drug and
alcohol treatment facilities; residents of hospices and nursing homes;
human remains; and individuals who donate or sell blood or blood
components.
Sterilize means the use of a physical or chemical procedure to
destroy all microbial life including highly resistant bacterial
endospores.
Universal Precautions is an approach to infection control. According
to the concept of Universal Precautions, all human blood and certain
human body fluids are treated as if known to be infectious for HIV, HBV,
and other bloodborne pathogens.
Work Practice Controls means controls that reduce the likelihood of
exposure by altering the manner in which a task is performed (e.g.,
prohibiting recapping of needles by a two-handed technique).
(c) Exposure control--(1) Exposure Control Plan. (i) Each employer
having an
[[Page 269]]
employee(s) with occupational exposure as defined by paragraph (b) of
this section shall establish a written Exposure Control Plan designed to
eliminate or minimize employee exposure.
(ii) The Exposure Control Plan shall contain at least the following
elements:
(A) The exposure determination required by paragraph (c)(2),
(B) The schedule and method of implementation for paragraphs (d)
Methods of Compliance, (e) HIV and HBV Research Laboratories and
Production Facilities, (f) Hepatitis B Vaccination and Post-Exposure
Evaluation and Follow-up, (g) Communication of Hazards to Employees, and
(h) Recordkeeping, of this standard, and
(C) The procedure for the evaluation of circumstances surrounding
exposure incidents as required by paragraph (f)(3)(i) of this standard.
(iii) Each employer shall ensure that a copy of the Exposure Control
Plan is accessible to employees in accordance with 29 CFR 1910.20(e).
(iv) The Exposure Control Plan shall be reviewed and updated at
least annually and whenever necessary to reflect new or modified tasks
and procedures which affect occupational exposure and to reflect new or
revised employee positions with occupational exposure. The review and
update of such plans shall also:
(A) Reflect changes in technology that eliminate or reduce exposure
to bloodborne pathogens; and
(B) Document annually consideration and implementation of
appropriate commercially available and effective safer medical devices
designed to eliminate or minimize occupational exposure.
(v) An employer, who is required to establish an Exposure Control
Plan shall solicit input from non-managerial employees responsible for
direct patient care who are potentially exposed to injuries from
contaminated sharps in the identification, evaluation, and selection of
effective engineering and work practice controls and shall document the
solicitation in the Exposure Control Plan.
(vi) The Exposure Control Plan shall be made available to the
Assistant Secretary and the Director upon request for examination and
copying.
(2) Exposure determination. (i) Each employer who has an employee(s)
with occupational exposure as defined by paragraph (b) of this section
shall prepare an exposure determination. This exposure determination
shall contain the following:
(A) A list of all job classifications in which all employees in
those job classifications have occupational exposure;
(B) A list of job classifications in which some employees have
occupational exposure, and
(C) A list of all tasks and procedures or groups of closely related
task and procedures in which occupational exposure occurs and that are
performed by employees in job classifications listed in accordance with
the provisions of paragraph (c)(2)(i)(B) of this standard.
(ii) This exposure determination shall be made without regard to the
use of personal protective equipment.
(d) Methods of compliance--(1) General. Universal precautions shall
be observed to prevent contact with blood or other potentially
infectious materials. Under circumstances in which differentiation
between body fluid types is difficult or impossible, all body fluids
shall be considered potentially infectious materials.
(2) Engineering and work practice controls. (i) Engineering and work
practice controls shall be used to eliminate or minimize employee
exposure. Where occupational exposure remains after institution of these
controls, personal protective equipment shall also be used.
(ii) Engineering controls shall be examined and maintained or
replaced on a regular schedule to ensure their effectiveness.
(iii) Employers shall provide handwashing facilities which are
readily accessible to employees.
(iv) When provision of handwashing facilities is not feasible, the
employer shall provide either an appropriate antiseptic hand cleanser in
conjunction with clean cloth/paper towels or antiseptic towelettes. When
antiseptic hand cleansers or towelettes are used, hands shall be washed
with soap and running water as soon as feasible.
[[Page 270]]
(v) Employers shall ensure that employees wash their hands
immediately or as soon as feasible after removal of gloves or other
personal protective equipment.
(vi) Employers shall ensure that employees wash hands and any other
skin with soap and water, or flush mucous membranes with water
immediately or as soon as feasible following contact of such body areas
with blood or other potentially infectious materials.
(vii) Contaminated needles and other contaminated sharps shall not
be bent, recapped, or removed except as noted in paragraphs
(d)(2)(vii)(A) and (d)(2)(vii)(B) below. Shearing or breaking of
contaminated needles is prohibited.
(A) Contaminated needles and other contaminated sharps shall not be
bent, recapped or removed unless the employer can demonstrate that no
alternative is feasible or that such action is required by a specific
medical or dental procedure.
(B) Such bending, recapping or needle removal must be accomplished
through the use of a mechanical device or a one-handed technique.
(viii) Immediately or as soon as possible after use, contaminated
reusable sharps shall be placed in appropriate containers until properly
reprocessed. These containers shall be:
(A) Puncture resistant;
(B) Labeled or color-coded in accordance with this standard;
(C) Leakproof on the sides and bottom; and
(D) In accordance with the requirements set forth in paragraph
(d)(4)(ii)(E) for reusable sharps.
(ix) Eating, drinking, smoking, applying cosmetics or lip balm, and
handling contact lenses are prohibited in work areas where there is a
reasonable likelihood of occupational exposure.
(x) Food and drink shall not be kept in refrigerators, freezers,
shelves, cabinets or on countertops or benchtops where blood or other
potentially infectious materials are present.
(xi) All procedures involving blood or other potentially infectious
materials shall be performed in such a manner as to minimize splashing,
spraying, spattering, and generation of droplets of these substances.
(xii) Mouth pipetting/suctioning of blood or other potentially
infectious materials is prohibited.
(xiii) Specimens of blood or other potentially infectious materials
shall be placed in a container which prevents leakage during collection,
handling, processing, storage, transport, or shipping.
(A) The container for storage, transport, or shipping shall be
labeled or color-coded according to paragraph (g)(1)(i) and closed prior
to being stored, transported, or shipped. When a facility utilizes
Universal Precautions in the handling of all specimens, the labeling/
color-coding of specimens is not necessary provided containers are
recognizable as containing specimens. This exemption only applies while
such specimens/containers remain within the facility. Labeling or color-
coding in accordance with paragraph (g)(1)(i) is required when such
specimens/containers leave the facility.
(B) If outside contamination of the primary container occurs, the
primary container shall be placed within a second container which
prevents leakage during handling, processing, storage, transport, or
shipping and is labeled or color-coded according to the requirements of
this standard.
(C) If the specimen could puncture the primary container, the
primary container shall be placed within a secondary container which is
puncture-resistant in addition to the above characteristics.
(xiv) Equipment which may become contaminated with blood or other
potentially infectious materials shall be examined prior to servicing or
shipping and shall be decontaminated as necessary, unless the employer
can demonstrate that decontamination of such equipment or portions of
such equipment is not feasible.
(A) A readily observable label in accordance with paragraph
(g)(1)(i)(H) shall be attached to the equipment stating which portions
remain contaminated.
(B) The employer shall ensure that this information is conveyed to
all affected employees, the servicing representative, and/or the
manufacturer,
[[Page 271]]
as appropriate, prior to handling, servicing, or shipping so that
appropriate precautions will be taken.
(3) Personal protective equipment--(i) Provision. When there is
occupational exposure, the employer shall provide, at no cost to the
employee, appropriate personal protective equipment such as, but not
limited to, gloves, gowns, laboratory coats, face shields or masks and
eye protection, and mouthpieces, resuscitation bags, pocket masks, or
other ventilation devices. Personal protective equipment will be
considered ``appropriate'' only if it does not permit blood or other
potentially infectious materials to pass through to or reach the
employee's work clothes, street clothes, undergarments, skin, eyes,
mouth, or other mucous membranes under normal conditions of use and for
the duration of time which the protective equipment will be used.
(ii) Use. The employer shall ensure that the employee uses
appropriate personal protective equipment unless the employer shows that
the employee temporarily and briefly declined to use personal protective
equipment when, under rare and extraordinary circumstances, it was the
employee's professional judgment that in the specific instance its use
would have prevented the delivery of health care or public safety
services or would have posed an increased hazard to the safety of the
worker or co-worker. When the employee makes this judgement, the
circumstances shall be investigated and documented in order to determine
whether changes can be instituted to prevent such occurances in the
future.
(iii) Accessibility. The employer shall ensure that appropriate
personal protective equipment in the appropriate sizes is readily
accessible at the worksite or is issued to employees. Hypoallergenic
gloves, glove liners, powderless gloves, or other similar alternatives
shall be readily accessible to those employees who are allergic to the
gloves normally provided.
(iv) Cleaning, Laundering, and Disposal. The employer shall clean,
launder, and dispose of personal protective equipment required by
paragraphs (d) and (e) of this standard, at no cost to the employee.
(v) Repair and Replacement. The employer shall repair or replace
personal protective equipment as needed to maintain its effectiveness,
at no cost to the employee.
(vi) If a garment(s) is penetrated by blood or other potentially
infectious materials, the garment(s) shall be removed immediately or as
soon as feasible.
(vii) All personal protective equipment shall be removed prior to
leaving the work area.
(viii) When personal protective equipment is removed it shall be
placed in an appropriately designated area or container for storage,
washing, decontamination or disposal.
(ix) Gloves. Gloves shall be worn when it can be reasonably
anticipated that the employee may have hand contact with blood, other
potentially infectious materials, mucous membranes, and non-intact skin;
when performing vascular access procedures except as specified in
paragraph (d)(3)(ix)(D); and when handling or touching contaminated
items or surfaces.
(A) Disposable (single use) gloves such as surgical or examination
gloves, shall be replaced as soon as practical when contaminated or as
soon as feasible if they are torn, punctured, or when their ability to
function as a barrier is compromised.
(B) Disposable (single use) gloves shall not be washed or
decontaminated for re-use.
(C) Utility gloves may be decontaminated for re-use if the integrity
of the glove is not compromised. However, they must be discarded if they
are cracked, peeling, torn, punctured, or exhibit other signs of
deterioration or when their ability to function as a barrier is
compromised.
(D) If an employer in a volunteer blood donation center judges that
routine gloving for all phlebotomies is not necessary then the employer
shall:
(1) Periodically reevaluate this policy;
(2) Make gloves available to all employees who wish to use them for
phlebotomy;
(3) Not discourage the use of gloves for phlebotomy; and
[[Page 272]]
(4) Require that gloves be used for phlebotomy in the following
circumstances:
(i) When the employee has cuts, scratches, or other breaks in his or
her skin;
(ii) When the employee judges that hand contamination with blood may
occur, for example, when performing phlebotomy on an uncooperative
source individual; and
(iii) When the employee is receiving training in phlebotomy.
(x) Masks, Eye Protection, and Face Shields. Masks in combination
with eye protection devices, such as goggles or glasses with solid side
shields, or chin-length face shields, shall be worn whenever splashes,
spray, spatter, or droplets of blood or other potentially infectious
materials may be generated and eye, nose, or mouth contamination can be
reasonably anticipated.
(xi) Gowns, Aprons, and Other Protective Body Clothing. Appropriate
protective clothing such as, but not limited to, gowns, aprons, lab
coats, clinic jackets, or similar outer garments shall be worn in
occupational exposure situations. The type and characteristics will
depend upon the task and degree of exposure anticipated.
(xii) Surgical caps or hoods and/or shoe covers or boots shall be
worn in instances when gross contamination can reasonably be anticipated
(e.g., autopsies, orthopaedic surgery).
(4) Housekeeping--(i) General. Employers shall ensure that the
worksite is maintained in a clean and sanitary condition. The employer
shall determine and implement an appropriate written schedule for
cleaning and method of decontamination based upon the location within
the facility, type of surface to be cleaned, type of soil present, and
tasks or procedures being performed in the area.
(ii) All equipment and environmental and working surfaces shall be
cleaned and decontaminated after contact with blood or other potentially
infectious materials.
(A) Contaminated work surfaces shall be decontaminated with an
appropriate disinfectant after completion of procedures; immediately or
as soon as feasible when surfaces are overtly contaminated or after any
spill of blood or other potentially infectious materials; and at the end
of the work shift if the surface may have become contaminated since the
last cleaning.
(B) Protective coverings, such as plastic wrap, aluminum foil, or
imperviously-backed absorbent paper used to cover equipment and
environmental surfaces, shall be removed and replaced as soon as
feasible when they become overtly contaminated or at the end of the
workshift if they may have become contaminated during the shift.
(C) All bins, pails, cans, and similar receptacles intended for
reuse which have a reasonable likelihood for becoming contaminated with
blood or other potentially infectious materials shall be inspected and
decontaminated on a regularly scheduled basis and cleaned and
decontaminated immediately or as soon as feasible upon visible
contamination.
(D) Broken glassware which may be contaminated shall not be picked
up directly with the hands. It shall be cleaned up using mechanical
means, such as a brush and dust pan, tongs, or forceps.
(E) Reusable sharps that are contaminated with blood or other
potentially infectious materials shall not be stored or processed in a
manner that requires employees to reach by hand into the containers
where these sharps have been placed.
(iii) Regulated Waste--(A) Contaminated Sharps Discarding and
Containment. (1) Contaminated sharps shall be discarded immediately or
as soon as feasible in containers that are:
(i) Closable;
(ii) Puncture resistant;
(iii) Leakproof on sides and bottom; and
(iv) Labeled or color-coded in accordance with paragraph (g)(1)(i)
of this standard.
(2) During use, containers for contaminated sharps shall be:
(i) Easily accessible to personnel and located as close as is
feasible to the immediate area where sharps are used or can be
reasonably anticipated to be found (e.g., laundries);
(ii) Maintained upright throughout use; and
(iii) Replaced routinely and not be allowed to overfill.
[[Page 273]]
(3) When moving containers of contaminated sharps from the area of
use, the containers shall be:
(i) Closed immediately prior to removal or replacement to prevent
spillage or protrusion of contents during handling, storage, transport,
or shipping;
(ii) Placed in a secondary container if leakage is possible. The
second container shall be:
(A) Closable;
(B) Constructed to contain all contents and prevent leakage during
handling, storage, transport, or shipping; and
(C) Labeled or color-coded according to paragraph (g)(1)(i) of this
standard.
(4) Reusable containers shall not be opened, emptied, or cleaned
manually or in any other manner which would expose employees to the risk
of percutaneous injury.
(B) Other Regulated Waste Containment--(1) Regulated waste shall be
placed in containers which are:
(i) Closable;
(ii) Constructed to contain all contents and prevent leakage of
fluids during handling, storage, transport or shipping;
(iii) Labeled or color-coded in accordance with paragraph (g)(1)(i)
this standard; and
(iv) Closed prior to removal to prevent spillage or protrusion of
contents during handling, storage, transport, or shipping.
(2) If outside contamination of the regulated waste container
occurs, it shall be placed in a second container. The second container
shall be:
(i) Closable;
(ii) Constructed to contain all contents and prevent leakage of
fluids during handling, storage, transport or shipping;
(iii) Labeled or color-coded in accordance with paragraph (g)(1)(i)
of this standard; and
(iv) Closed prior to removal to prevent spillage or protrusion of
contents during handling, storage, transport, or shipping.
(C) Disposal of all regulated waste shall be in accordance with
applicable regulations of the United States, States and Territories, and
political subdivisions of States and Territories.
(iv) Laundry. (A) Contaminated laundry shall be handled as little as
possible with a minimum of agitation. (1) Contaminated laundry shall be
bagged or containerized at the location where it was used and shall not
be sorted or rinsed in the location of use.
(2) Contaminated laundry shall be placed and transported in bags or
containers labeled or color-coded in accordance with paragraph (g)(1)(i)
of this standard. When a facility utilizes Universal Precautions in the
handling of all soiled laundry, alternative labeling or color-coding is
sufficient if it permits all employees to recognize the containers as
requiring compliance with Universal Precautions.
(3) Whenever contaminated laundry is wet and presents a reasonable
likelihood of soak-through of or leakage from the bag or container, the
laundry shall be placed and transported in bags or containers which
prevent soak-through and/or leakage of fluids to the exterior.
(B) The employer shall ensure that employees who have contact with
contaminated laundry wear protective gloves and other appropriate
personal protective equipment.
(C) When a facility ships contaminated laundry off-site to a second
facility which does not utilize Universal Precautions in the handling of
all laundry, the facility generating the contaminated laundry must place
such laundry in bags or containers which are labeled or color-coded in
accordance with paragraph (g)(1)(i).
(e) HIV and HBV Research Laboratories and Production Facilities. (1)
This paragraph applies to research laboratories and production
facilities engaged in the culture, production, concentration,
experimentation, and manipulation of HIV and HBV. It does not apply to
clinical or diagnostic laboratories engaged solely in the analysis of
blood, tissues, or organs. These requirements apply in addition to the
other requirements of the standard.
(2) Research laboratories and production facilities shall meet the
following criteria:
(i) Standard microbiological practices. All regulated waste shall
either be incinerated or decontaminated by a method such as autoclaving
known to
[[Page 274]]
effectively destroy bloodborne pathogens.
(ii) Special practices. (A) Laboratory doors shall be kept closed
when work involving HIV or HBV is in progress.
(B) Contaminated materials that are to be decontaminated at a site
away from the work area shall be placed in a durable, leakproof, labeled
or color-coded container that is closed before being removed from the
work area.
(C) Access to the work area shall be limited to authorized persons.
Written policies and procedures shall be established whereby only
persons who have been advised of the potential biohazard, who meet any
specific entry requirements, and who comply with all entry and exit
procedures shall be allowed to enter the work areas and animal rooms.
(D) When other potentially infectious materials or infected animals
are present in the work area or containment module, a hazard warning
sign incorporating the universal biohazard symbol shall be posted on all
access doors. The hazard warning sign shall comply with paragraph
(g)(1)(ii) of this standard.
(E) All activities involving other potentially infectious materials
shall be conducted in biological safety cabinets or other physical-
containment devices within the containment module. No work with these
other potentially infectious materials shall be conducted on the open
bench.
(F) Laboratory coats, gowns, smocks, uniforms, or other appropriate
protective clothing shall be used in the work area and animal rooms.
Protective clothing shall not be worn outside of the work area and shall
be decontaminated before being laundered.
(G) Special care shall be taken to avoid skin contact with other
potentially infectious materials. Gloves shall be worn when handling
infected animals and when making hand contact with other potentially
infectious materials is unavoidable.
(H) Before disposal all waste from work areas and from animal rooms
shall either be incinerated or decontaminated by a method such as
autoclaving known to effectively destroy bloodborne pathogens.
(I) Vacuum lines shall be protected with liquid disinfectant traps
and high-efficiency particulate air (HEPA) filters or filters of
equivalent or superior efficiency and which are checked routinely and
maintained or replaced as necessary.
(J) Hypodermic needles and syringes shall be used only for
parenteral injection and aspiration of fluids from laboratory animals
and diaphragm bottles. Only needle-locking syringes or disposable
syringe-needle units (i.e., the needle is integral to the syringe) shall
be used for the injection or aspiration of other potentially infectious
materials. Extreme caution shall be used when handling needles and
syringes. A needle shall not be bent, sheared, replaced in the sheath or
guard, or removed from the syringe following use. The needle and syringe
shall be promptly placed in a puncture-resistant container and
autoclaved or decontaminated before reuse or disposal.
(K) All spills shall be immediately contained and cleaned up by
appropriate professional staff or others properly trained and equipped
to work with potentially concentrated infectious materials.
(L) A spill or accident that results in an exposure incident shall
be immediately reported to the laboratory director or other responsible
person.
(M) A biosafety manual shall be prepared or adopted and periodically
reviewed and updated at least annually or more often if necessary.
Personnel shall be advised of potential hazards, shall be required to
read instructions on practices and procedures, and shall be required to
follow them.
(iii) Containment equipment. (A) Certified biological safety
cabinets (Class I, II, or III) or other appropriate combinations of
personal protection or physical containment devices, such as special
protective clothing, respirators, centrifuge safety cups, sealed
centrifuge rotors, and containment caging for animals, shall be used for
all activities with other potentially infectious materials that pose a
threat of exposure to droplets, splashes, spills, or aerosols.
[[Page 275]]
(B) Biological safety cabinets shall be certified when installed,
whenever they are moved and at least annually.
(3) HIV and HBV research laboratories shall meet the following
criteria:
(i) Each laboratory shall contain a facility for hand washing and an
eye wash facility which is readily available within the work area.
(ii) An autoclave for decontamination of regulated waste shall be
available.
(4) HIV and HBV production facilities shall meet the following
criteria:
(i) The work areas shall be separated from areas that are open to
unrestricted traffic flow within the building. Passage through two sets
of doors shall be the basic requirement for entry into the work area
from access corridors or other contiguous areas. Physical separation of
the high-containment work area from access corridors or other areas or
activities may also be provided by a double-doored clothes-change room
(showers may be included), airlock, or other access facility that
requires passing through two sets of doors before entering the work
area.
(ii) The surfaces of doors, walls, floors and ceilings in the work
area shall be water resistant so that they can be easily cleaned.
Penetrations in these surfaces shall be sealed or capable of being
sealed to facilitate decontamination.
(iii) Each work area shall contain a sink for washing hands and a
readily available eye wash facility. The sink shall be foot, elbow, or
automatically operated and shall be located near the exit door of the
work area.
(iv) Access doors to the work area or containment module shall be
self-closing.
(v) An autoclave for decontamination of regulated waste shall be
available within or as near as possible to the work area.
(vi) A ducted exhaust-air ventilation system shall be provided. This
system shall create directional airflow that draws air into the work
area through the entry area. The exhaust air shall not be recirculated
to any other area of the building, shall be discharged to the outside,
and shall be dispersed away from occupied areas and air intakes. The
proper direction of the airflow shall be verified (i.e., into the work
area).
(5) Training Requirements. Additional training requirements for
employees in HIV and HBV research laboratories and HIV and HBV
production facilities are specified in paragraph (g)(2)(ix).
(f) Hepatitis B vaccination and post-exposure evaluation and follow-
up--(1) General. (i) The employer shall make available the hepatitis B
vaccine and vaccination series to all employees who have occupational
exposure, and post-exposure evaluation and follow-up to all employees
who have had an exposure incident.
(ii) The employer shall ensure that all medical evaluations and
procedures including the hepatitis B vaccine and vaccination series and
post-exposure evaluation and follow-up, including prophylaxis, are:
(A) Made available at no cost to the employee;
(B) Made available to the employee at a reasonable time and place;
(C) Performed by or under the supervision of a licensed physician or
by or under the supervision of another licensed healthcare professional;
and
(D) Provided according to recommendations of the U.S. Public Health
Service current at the time these evaluations and procedures take place,
except as specified by this paragraph (f).
(iii) The employer shall ensure that all laboratory tests are
conducted by an accredited laboratory at no cost to the employee.
(2) Hepatitis B Vaccination. (i) Hepatitis B vaccination shall be
made available after the employee has received the training required in
paragraph (g)(2)(vii)(I) and within 10 working days of initial
assignment to all employees who have occupational exposure unless the
employee has previously received the complete hepatitis B vaccination
series, antibody testing has revealed that the employee is immune, or
the vaccine is contraindicated for medical reasons.
(ii) The employer shall not make participation in a prescreening
program a prerequisite for receiving hepatitis B vaccination.
[[Page 276]]
(iii) If the employee initially declines hepatitis B vaccination but
at a later date while still covered under the standard decides to accept
the vaccination, the employer shall make available hepatitis B
vaccination at that time.
(iv) The employer shall assure that employees who decline to accept
hepatitis B vaccination offered by the employer sign the statement in
appendix A.
(v) If a routine booster dose(s) of hepatitis B vaccine is
recommended by the U.S. Public Health Service at a future date, such
booster dose(s) shall be made available in accordance with section
(f)(1)(ii).
(3) Post-exposure Evaluation and Follow-up. Following a report of an
exposure incident, the employer shall make immediately available to the
exposed employee a confidential medical evaluation and follow-up,
including at least the following elements:
(i) Documentation of the route(s) of exposure, and the circumstances
under which the exposure incident occurred;
(ii) Identification and documentation of the source individual,
unless the employer can establish that identification is infeasible or
prohibited by state or local law;
(A) The source individual's blood shall be tested as soon as
feasible and after consent is obtained in order to determine HBV and HIV
infectivity. If consent is not obtained, the employer shall establish
that legally required consent cannot be obtained. When the source
individual's consent is not required by law, the source individual's
blood, if available, shall be tested and the results documented.
(B) When the source individual is already known to be infected with
HBV or HIV, testing for the source individual's known HBV or HIV status
need not be repeated.
(C) Results of the source individual's testing shall be made
available to the exposed employee, and the employee shall be informed of
applicable laws and regulations concerning disclosure of the identity
and infectious status of the source individual.
(iii) Collection and testing of blood for HBV and HIV serological
status;
(A) The exposed employee's blood shall be collected as soon as
feasible and tested after consent is obtained.
(B) If the employee consents to baseline blood collection, but does
not give consent at that time for HIV serologic testing, the sample
shall be preserved for at least 90 days. If, within 90 days of the
exposure incident, the employee elects to have the baseline sample
tested, such testing shall be done as soon as feasible.
(iv) Post-exposure prophylaxis, when medically indicated, as
recommended by the U.S. Public Health Service;
(v) Counseling; and
(vi) Evaluation of reported illnesses.
(4) Information Provided to the Healthcare Professional. (i) The
employer shall ensure that the healthcare professional responsible for
the employee's Hepatitis B vaccination is provided a copy of this
regulation.
(ii) The employer shall ensure that the healthcare professional
evaluating an employee after an exposure incident is provided the
following information:
(A) A copy of this regulation;
(B) A description of the exposed employee's duties as they relate to
the exposure incident;
(C) Documentation of the route(s) of exposure and circumstances
under which exposure occurred;
(D) Results of the source individual's blood testing, if available;
and
(E) All medical records relevant to the appropriate treatment of the
employee including vaccination status which are the employer's
responsibility to maintain.
(5) Healthcare Professional's Written Opinion. The employer shall
obtain and provide the employee with a copy of the evaluating healthcare
professional's written opinion within 15 days of the completion of the
evaluation.
(i) The healthcare professional's written opinion for Hepatitis B
vaccination shall be limited to whether Hepatitis B vaccination is
indicated for an employee, and if the employee has received such
vaccination.
(ii) The healthcare professional's written opinion for post-exposure
evaluation and follow-up shall be limited to the following information:
[[Page 277]]
(A) That the employee has been informed of the results of the
evaluation; and
(B) That the employee has been told about any medical conditions
resulting from exposure to blood or other potentially infectious
materials which require further evaluation or treatment. (iii) All other
findings or diagnoses shall remain confidential and shall not be
included in the written report.
(6) Medical recordkeeping. Medical records required by this standard
shall be maintained in accordance with paragraph (h)(1) of this section.
(g) Communication of hazards to employees--(1) Labels and signs--(i)
Labels. (A) Warning labels shall be affixed to containers of regulated
waste, refrigerators and freezers containing blood or other potentially
infectious material; and other containers used to store, transport or
ship blood or other potentially infectious materials, except as provided
in paragraph (g)(1)(i)(E), (F) and (G).
(B) Labels required by this section shall include the following
legend:
[GRAPHIC] [TIFF OMITTED] TC28OC91.018
(C) These labels shall be fluorescent orange or orange-red or
predominantly so, with lettering and symbols in a contrasting color.
(D) Labels shall be affixed as close as feasible to the container by
string, wire, adhesive, or other method that prevents their loss or
unintentional removal.
(E) Red bags or red containers may be substituted for labels.
(F) Containers of blood, blood components, or blood products that
are labeled as to their contents and have been released for transfusion
or other clinical use are exempted from the labeling requirements of
paragraph (g).
(G) Individual containers of blood or other potentially infectious
materials that are placed in a labeled container during storage,
transport, shipment or disposal are exempted from the labeling
requirement.
(H) Labels required for contaminated equipment shall be in
accordance with this paragraph and shall also state which portions of
the equipment remain contaminated.
(I) Regulated waste that has been decontaminated need not be labeled
or color-coded.
(ii) Signs. (A) The employer shall post signs at the entrance to
work areas specified in paragraph (e), HIV and HBV Research Laboratory
and Production Facilities, which shall bear the following legend:
[GRAPHIC] [TIFF OMITTED] TC28OC91.019
(Name of the Infectious Agent)
(Special requirements for entering the area)
(Name, telephone number of the laboratory director or other responsible
person.)
(B) These signs shall be fluorescent orange-red or predominantly so,
with lettering and symbols in a contrasting color.
(2) Information and Training. (i) The employer shall train each
employee with occupational exposure in accordance with the requirements
of this section. Such training must be provided at no cost to the
employee and during working hours. The employer shall institute a
training program and ensure employee participation in the program.
(ii) Training shall be provided as follows:
(A) At the time of initial assignment to tasks where occupational
exposure may take place;
(B) At least annually thereafter.
(iii) [Reserved]
[[Page 278]]
(iv) Annual training for all employees shall be provided within one
year of their previous training.
(v) Employers shall provide additional training when changes such as
modification of tasks or procedures or institution of new tasks or
procedures affect the employee's occupational exposure. The additional
training may be limited to addressing the new exposures created.
(vi) Material appropriate in content and vocabulary to educational
level, literacy, and language of employees shall be used.
(vii) The training program shall contain at a minimum the following
elements:
(A) An accessible copy of the regulatory text of this standard and
an explanation of its contents;
(B) A general explanation of the epidemiology and symptoms of
bloodborne diseases;
(C) An explanation of the modes of transmission of bloodborne
pathogens;
(D) An explanation of the employer's exposure control plan and the
means by which the employee can obtain a copy of the written plan;
(E) An explanation of the appropriate methods for recognizing tasks
and other activities that may involve exposure to blood and other
potentially infectious materials;
(F) An explanation of the use and limitations of methods that will
prevent or reduce exposure including appropriate engineering controls,
work practices, and personal protective equipment;
(G) Information on the types, proper use, location, removal,
handling, decontamination and disposal of personal protective equipment;
(H) An explanation of the basis for selection of personal protective
equipment;
(I) Information on the hepatitis B vaccine, including information on
its efficacy, safety, method of administration, the benefits of being
vaccinated, and that the vaccine and vaccination will be offered free of
charge;
(J) Information on the appropriate actions to take and persons to
contact in an emergency involving blood or other potentially infectious
materials;
(K) An explanation of the procedure to follow if an exposure
incident occurs, including the method of reporting the incident and the
medical follow-up that will be made available;
(L) Information on the post-exposure evaluation and follow-up that
the employer is required to provide for the employee following an
exposure incident;
(M) An explanation of the signs and labels and/or color coding
required by paragraph (g)(1); and
(N) An opportunity for interactive questions and answers with the
person conducting the training session.
(viii) The person conducting the training shall be knowledgeable in
the subject matter covered by the elements contained in the training
program as it relates to the workplace that the training will address.
(ix) Additional Initial Training for Employees in HIV and HBV
Laboratories and Production Facilities. Employees in HIV or HBV research
laboratories and HIV or HBV production facilities shall receive the
following initial training in addition to the above training
requirements.
(A) The employer shall assure that employees demonstrate proficiency
in standard microbiological practices and techniques and in the
practices and operations specific to the facility before being allowed
to work with HIV or HBV.
(B) The employer shall assure that employees have prior experience
in the handling of human pathogens or tissue cultures before working
with HIV or HBV.
(C) The employer shall provide a training program to employees who
have no prior experience in handling human pathogens. Initial work
activities shall not include the handling of infectious agents. A
progression of work activities shall be assigned as techniques are
learned and proficiency is developed. The employer shall assure that
employees participate in work activities involving infectious agents
only after proficiency has been demonstrated.
(h) Recordkeeping--(1) Medical Records. (i) The employer shall
establish and maintain an accurate record for each employee with
occupational
[[Page 279]]
exposure, in accordance with 29 CFR 1910.1020.
(ii) This record shall include:
(A) The name and social security number of the employee;
(B) A copy of the employee's hepatitis B vaccination status
including the dates of all the hepatitis B vaccinations and any medical
records relative to the employee's ability to receive vaccination as
required by paragraph (f)(2);
(C) A copy of all results of examinations, medical testing, and
follow-up procedures as required by paragraph (f)(3);
(D) The employer's copy of the healthcare professional's written
opinion as required by paragraph (f)(5); and
(E) A copy of the information provided to the healthcare
professional as required by paragraphs (f)(4)(ii)(B)(C) and (D).
(iii) Confidentiality. The employer shall ensure that employee
medical records required by paragraph (h)(1) are:
(A) Kept confidential; and
(B) Not disclosed or reported without the employee's express written
consent to any person within or outside the workplace except as required
by this section or as may be required by law.
(iv) The employer shall maintain the records required by paragraph
(h) for at least the duration of employment plus 30 years in accordance
with 29 CFR 1910.1020.
(2) Training Records. (i) Training records shall include the
following information:
(A) The dates of the training sessions;
(B) The contents or a summary of the training sessions;
(C) The names and qualifications of persons conducting the training;
and
(D) The names and job titles of all persons attending the training
sessions.
(ii) Training records shall be maintained for 3 years from the date
on which the training occurred.
(3) Availability. (i) The employer shall ensure that all records
required to be maintained by this section shall be made available upon
request to the Assistant Secretary and the Director for examination and
copying.
(ii) Employee training records required by this paragraph shall be
provided upon request for examination and copying to employees, to
employee representatives, to the Director, and to the Assistant
Secretary.
(iii) Employee medical records required by this paragraph shall be
provided upon request for examination and copying to the subject
employee, to anyone having written consent of the subject employee, to
the Director, and to the Assistant Secretary in accordance with 29 CFR
1910.1020.
(4) Transfer of Records. The employer shall comply with the
requirements involving transfer of records set forth in 29 CFR
1910.1020(h).
(5) Sharps injury log. (i) The employer shall establish and maintain
a sharps injury log for the recording of percutaneous injuries from
contaminated sharps. The information in the sharps injury log shall be
recorded and maintained in such manner as to protect the confidentiality
of the injured employee. The sharps injury log shall contain, at a
minimum:
(A) The type and brand of device involved in the incident,
(B) The department or work area where the exposure incident
occurred, and
(C) An explanation of how the incident occurred.
(ii) The requirement to establish and maintain a sharps injury log
shall apply to any employer who is required to maintain a log of
occupational injuries and illnesses under 29 CFR part 1904.
(iii) The sharps injury log shall be maintained for the period
required by 29 CFR 1904.33.
(i) Dates--(1) Effective Date. The standard shall become effective
on March 6, 1992.
(2) The Exposure Control Plan required by paragraph (c) of this
section shall be completed on or before May 5, 1992.
(3) Paragraphs (g)(2) Information and Training and (h) Recordkeeping
of this section shall take effect on or before June 4, 1992.
(4) Paragraphs (d)(2) Engineering and Work Practice Controls, (d)(3)
Personal Protective Equipment, (d)(4) Housekeeping, (e) HIV and HBV
Research
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Laboratories and Production Facilities, (f) Hepatitis B Vaccination and
Post-Exposure Evaluation and Follow-up, and (g)(1) Labels and Signs of
this section, shall take effect July 6, 1992.
Appendix A to Section 1910.1030--Hepatitis B Vaccine Declination
(Mandatory)
I understand that due to my occupational exposure to blood or other
potentially infectious materials I may be at risk of acquiring hepatitis
B virus (HBV) infection. I have been given the opportunity to be
vaccinated with hepatitis B vaccine, at no charge to myself. However, I
decline hepatitis B vaccination at this time. I understand that by
declining this vaccine, I continue to be at risk of acquiring hepatitis
B, a serious disease. If in the future I continue to have occupational
exposure to blood or other potentially infectious materials and I want
to be vaccinated with hepatitis B vaccine, I can receive the vaccination
series at no charge to me.
[56 FR 64175, Dec. 6, 1991, as amended at 57 FR 12717, Apr. 13, 1992; 57
FR 29206, July 1, 1992; 61 FR 5508, Feb. 13, 1996; 66 FR 5325, Jan. 18,
2001; 71 FR 16672, 16673, Apr. 3, 2006; 73 FR 75586, Dec. 12, 2008; 76
FR 33608, June 8, 2011; 76 FR 80740, Dec. 27, 2011; 77 FR 19934, Apr. 3,
2012]
Sec. 1910.1043 Cotton dust.
(a) Scope and application. (1) This section, in its entirety,
applies to the control of employee exposure to cotton dust in all
workplaces where employees engage in yarn manufacturing, engage in
slashing and weaving operations, or work in waste houses for textile
operations.
(2) This section does not apply to the handling or processing of
woven or knitted materials; to maritime operations covered by 29 CFR
Parts 1915 and 1918; to harvesting or ginning of cotton; or to the
construction industry.
(3) Only paragraphs (h) Medical surveillance, (k)(2) through (4)
Recordkeeping--Medical Records, and Appendices B, C and D of this
section apply in all work places where employees exposed to cotton dust
engage in cottonseed processing or waste processing operations.
(4) This section applies to yarn manufacturing and slashing and
weaving operations exclusively using washed cotton (as defined by
paragraph (n) of this section) only to the extent specified by paragraph
(n) of this section.
(5) This section, in its entirety, applies to the control of all
employees exposure to the cotton dust generated in the preparation of
washed cotton from opening until the cotton is thoroughly wetted.
(6) This section does not apply to knitting, classing or warehousing
operations except that employers with these operations, if requested by
NIOSH, shall grant NIOSH access to their employees and workplaces for
exposure monitoring and medical examinations for purposes of a health
study to be performed by NIOSH on a sampling basis.
(b) Definitions. For the purpose of this section:
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee;
Blow down means the general cleaning of a room or a part of a room
by the use of compressed air.
Blow off means the use of compressed air for cleaning of short
duration and usually for a specific machine or any portion of a machine.
Cotton dust means dust present in the air during the handling or
processing of cotton, which may contain a mixture of many substances
including ground up plant matter, fiber, bacteria, fungi, soil,
pesticides, non-cotton plant matter and other contaminants which may
have accumulated with the cotton during the growing, harvesting and
subsequent processing or storage periods. Any dust present during the
handling and processing of cotton through the weaving or knitting of
fabrics, and dust present in other operations or manufacturing processes
using raw or waste cotton fibers or cotton fiber byproducts from textile
mills are considered cotton dust within this definition. Lubricating oil
mist associated with weaving operations is not considered cotton dust.
Director means the Director of the National Institute for
Occupational Safety and Health (NIOSH), U.S. Department of Health and
Human Services, or designee.
Equivalent Instrument means a cotton dust sampling device that meets
the
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vertical elutriator equivalency requirements as described in paragraph
(d)(1)(iii) of this section.
Lint-free respirable cotton dust means particles of cotton dust of
approximately 15 micrometers or less aerodynamic equivalent diameter;
Vertical elutriator cotton dust sampler or vertical elutriator means
a dust sampler which has a particle size cut-off at approximately 15
micrometers aerodynamic equivalent diameter when operating at the flow
rate of 7.4 0.2 liters of air per minute;
Waste processing means waste recycling (sorting, blending, cleaning
and willowing) and garnetting.
Yarn manufacturing means all textile mill operations from opening
to, but not including, slashing and weaving.
(c) Permissible exposure limits and action levels--(1) Permissible
exposure limits (PEL). (i) The employer shall assure that no employee
who is exposed to cotton dust in yarn manufacturing and cotton washing
operations is exposed to airborne concentrations of lint-free respirable
cotton dust greater than 200 [micro]g/m\3\ mean concentration, averaged
over an eight-hour period, as measured be a vertical elutriator or an
equivalent instrument.
(ii) The employer shall assure that no employee who is exposed to
cotton dust in textile mill waste house operations or is exposed in yarn
manufacturing to dust from ``lower grade washed cotton'' as defined in
paragraph (n)(5) of this section is exposed to airborne concentrations
of lint-free respirable cotton dust greater than 500 [micro]g/m\3\ mean
concentration, averaged over an eight-hour period, as measured by a
vertical elutriator or an equivalent instrument.
(iii) The employer shall assure that no employee who is exposed to
cotton dust in the textile processes known as slashing and weaving is
exposed to airborne concentrations of lint-free respirable cotton dust
greater than 750 [micro]g/m\3\ mean concentration, averaged over an
eight hour period, as measured by a vertical elutriator or an equivalent
instrument.
(2) Action levels. (i) The action level for yarn manufacturing and
cotton washing operations is an airborne concentration of lint-free
respirable cotton dust of 100 [micro]g/m\3\ mean concentration, averaged
over an eight-hour period, as measured by a vertical elutriator or an
equivalent instrument.
(ii) The action level for waste houses for textile operations is an
airborne concentration of lint-free respirable cotton dust of 250
[micro]g/m\3\ mean concentration, averaged over an eight-hour period, as
measured by a vertical elutriator or an equivalent instrument.
(iii) The action level for the textile processes known as slashing
and weaving is an airborne concentration of lint-free respirable cotton
dust of 375 [micro]g/m\3\ mean concentration, averaged over an eight-
hour period, as measured by a vertical elutriator or an equivalent
instrument.
(d) Exposure monitoring and measurement--(1) General. (i) For the
purposes of this section, employee exposure is that exposure which would
occur if the employee were not using a respirator.
(ii) The sampling device to be used shall be either the vertical
elutriator cotton dust sampler or an equivalent instrument.
(iii) If an alternative to the vertical elutriator cotton dust
sampler is used, the employer shall establish equivalency by reference
to an OSHA opinion or by documenting, based on data developed by the
employer or supplied by the manufacturer, that the alternative sampling
devices meets the following criteria:
(A) It collects respirable particulates in the same range as the
vertical elutriator (approximately 15 microns);
(B) Replicate exposure data used to establish equivalency are
collected in side-by-side field and laboratory comparisons; and
(C) A minimum of 100 samples over the range of 0.5 to 2 times the
permissible exposure limit are collected, and 90% of these samples have
an accuracy range of plus or minus 25 per cent of the vertical
elutriator reading with a 95% confidence level as demonstrated by a
statistically valid protocol. (An acceptable protocol for demonstrating
equivalency is described in appendix E of this section.)
(iv) OSHA will issue a written opinion stating that an instrument is
equivalent to a vertical elutriator cotton dust sampler if
[[Page 282]]
(A) A manufacturer or employer requests an opinion in writing and
supplies the following information:
(1) Sufficient test data to demonstrate that the instrument meets
the requirements specified in this paragraph and the protocol specified
in appendix E of this section;
(2) Any other relevant information about the instrument and its
testing requested by OSHA; and
(3) A certification by the manufacturer or employer that the
information supplied is accurate, and
(B) if OSHA finds, based on information submitted about the
instrument, that the instrument meets the requirements for equivalency
specified by paragraph (d) of this section.
(2) Initial monitoring. Each employer who has a place of employment
within the scope of paragraph (a)(1), (a)(4), or (a)(5) of this section
shall conduct monitoring by obtaining measurements which are
representative of the exposure of all employees to airborne
concentrations of lint-free respirable cotton dust over an eight-hour
period. The sampling program shall include at least one determination
during each shift for each work area.
(3) Periodic monitoring. (i) If the initial monitoring required by
paragraph (d)(2) of this section or any subsequent monitoring reveals
employee exposure to be at or below the permissible exposure limit, the
employer shall repeat the monitoring for those employees at least
annually.
(ii) If the initial monitoring required by paragraph (d)(2) of this
section or any subsequent monitoring reveals employee exposure to be
above the PEL, the employer shall repeat the monitoring for those
employees at least every six months.
(iii) Whenever there has been a production, process, or control
change which may result in new or additional exposure to cotton dust, or
whenever the employer has any other reason to suspect an increase in
employee exposure, the employer shall repeat the monitoring and
measurements for those employees affected by the change or increase.
(4) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each affected employee of these results either
individually in writing or by posting the results in an appropriate
location that is accessible to employees.
(ii) Whenever the results indicate that the employee's exposure
exceeds the applicable permissible exposure limit specified in paragraph
(c) of this section, the employer shall include in the written notice a
statement that the permissible exposure limit was exceeded and a
description of the corrective action taken to reduce exposure below the
permissible exposure limit.
(e) Methods of compliance--(1) Engineering and work practice
controls. The employer shall institute engineering and work practice
controls to reduce and maintain employee exposure to cotton dust at or
below the permissible exposure limit specified in paragraph (c) of this
section, except to the extent that the employer can establish that such
controls are not feasible.
(2) Whenever feasible engineering and work practice controls are not
sufficient to reduce employee exposure to or below the permissible
exposure limit, the employer shall nonetheless institute these controls
to reduce exposure to the lowest feasible level, and shall supplement
these controls with the use of respirators which shall comply with the
provisions of paragraph (f) of this section.
(3) Compliance program. (i) Where the most recent exposure
monitoring data indicates that any employee is exposed to cotton dust
levels greater than the permissible exposure limit, the employer shall
establish and implement a written program sufficient to reduce exposures
to or below the permissible exposure limit solely by means of
engineering controls and work practices as required by paragraph (e)(1)
of this section.
(ii) The written program shall include at least the following:
(A) A description of each operation or process resulting in employee
exposure to cotton dust at levels greater than the PEL;
(B) Engineering plans and other studies used to determine the
controls for each process;
[[Page 283]]
(C) A report of the technology considered in meeting the permissible
exposure limit;
(D) Monitoring data obtained in accordance with paragraph (d) of
this section;
(E) A detailed schedule for development and implementation of
engineering and work practice controls, including exposure levels
projected to be achieved by such controls;
(F) Work practice program; and
(G) Other relevant information.
(iii) The employer's schedule as set forth in the compliance
program, shall project completion of the implementation of the
compliance program no later than March 27, 1984 or as soon as possible
if monitoring after March 27, 1984 reveals exposures over the PEL,
except as provided in paragraph (m)(2)(ii)(B) of this section.
(iv) The employer shall complete the steps set forth in his program
by the dates in the schedule.
(v) Written programs shall be submitted, upon request, to the
Assistant Secretary and the Director, and shall be available at the
worksite for examination and copying by the Assistant Secretary, the
Director, and any affected employee or their designated representatives.
(vi) The written program required under paragraph (e)(3) of this
section shall be revised and updated when necessary to reflect the
current status of the program and current exposure levels.
(4) Mechanical ventilation. When mechanical ventilation is used to
control exposure, measurements which demonstrate the effectiveness of
the system to control exposure, such as capture velocity, duct velocity,
or static pressure shall be made at reasonable intervals.
(f) Respiratory protection--(1) General. For employees who are
required to use respirators by this section, the employer must provide
each employee an appropriate respirator that complies with the
requirements of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Maintenance and repair activities for which engineering and
work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the permissible exposure limits.
(iv) Work operations specified under paragraph (g)(1) of this
section.
(v) Periods for which an employee requests a respirator.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii)), and (f) through (m), which covers each
employee required by this section to use a respirator.
(ii) Whenever a physician determines that an employee who works in
an area in which the cotton-dust concentration exceeds the PEL is unable
to use a respirator, including a powered air-purifying respirator, the
employee must be given the opportunity to transfer to an available
position, or to a position that becomes available later, that has a
cotton-dust concentration at or below the PEL. The employer must ensure
that such employees retain their current wage rate or other benefits as
a result of the transfer.
(3) Respirator selection. (i) Employers must:
(A) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134; however,
employers must not select or use filtering facepieces for protection
against cotton dust concentrations greater than five times (5 x) the
PEL.
(B) Provide HEPA filters for powered and non-powered air-purifying
respirators used at cotton dust concentrations greater than ten times
(10 x) the PEL.
(ii) Employers must provide an employee with a powered air-purifying
respirator (PAPR) instead of a non-powered air-purifying respirator
selected according to paragraph (f)(3)(i) of this standard when the
employee chooses to use a PAPR and it provides adequate protection to
the employee as specified by paragraph (f)(3)(i) of this standard.
[[Page 284]]
(g) Work practices. Each employer shall, regardless of the level of
employee exposure, immediately establish and implement a written program
of work practices which shall minimize cotton dust exposure. The
following shall be included were applicable:
(1) Compressed air ``blow down'' cleaning shall be prohibited where
alternative means are feasible. Where compressed air is used for
cleaning, the employees performing the ``blow down'' or ``blow off''
shall wear suitable respirators. Employees whose presence is not
required to perform ``blow down'' or ``blow of'' shall be required to
leave the area affected by the ``blow down'' or ``blow off'' during this
cleaning operation.
(2) Cleaning of clothing or floors with compressed air shall be
prohibited.
(3) Floor sweeping shall be performed with a vacuum or with methods
designed to minimize dispersal of dust.
(4) In areas where employees are exposed to concentrations of cotton
dust greater than the permissible exposure limit, cotton and cotton
waste shall be stacked, sorted, baled, dumped, removed or otherwise
handled by mechanical means, except where the employer can show that it
is infeasible to do so. Where infeasible, the method used for handling
cotton and cotton waste shall be the method which reduces exposure to
the lowest level feasible.
(h) Medical survelliance--(1) General. (i) Each employer covered by
the standard shall institute a program of medical surveillance for all
employees exposed to cotton dust.
(ii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician and are provided without cost to the employee.
(iii) Persons other than licensed physicians, who administer the
pulmonary function testing required by this section shall have completed
a NIOSH-approved training course in spirometry.
(2) Initial examinations. The employer shall provide medical
surveillance to each employee who is or may be exposed to cotton dust.
For new employees, this examination shall be provided prior to initial
assignment. The medical surveillance shall include at least the
following:
(i) A medical history;
(ii) The standardized questionnaire contained in appendix B; and
(iii) A pulmonary function measurement, including a determination of
forced vital capacity (FVC) and forced expiratory volume in one second
(FEV1), the FEV1/FVC ratio, and the percentage
that the measured values of FEV1 and FVC differ from the
predicted values, using the standard tables in appendix C. These
determinations shall be made for each employee before the employee
enters the workplace on the first day of the work week, preceded by at
least 35 hours of no exposure to cotton dust. The tests shall be
repeated during the shift, no less than 4 and no more than 10 hours
after the beginning of the work shift; and, in any event, no more than
one hour after cessation of exposure. Such exposure shall be typical of
the employee's usual workplace exposure. The predicted FEV1
and FVC for blacks shall be multiplied by 0.85 to adjust for ethnic
differences.
(iv) Based upon the questionnaire results, each employee shall be
graded according to Schilling's byssinosis classification system.
(3) Periodic examinations. (i) The employer shall provide at least
annual medical surveillance for all employees exposed to cotton dust
above the action level in yarn manufacturing, slashing and weaving,
cotton washing and waste house operations. The employer shall provide
medical surveillance at least every two years for all employees exposed
to cotton dust at or below the action level, for all employees exposed
to cotton dust from washed cotton (except from washed cotton defined in
paragraph (n)(3) of this section), and for all employees exposed to
cotton dust in cottonseed processing and waste processing operations.
Periodic medical surveillance shall include at least an update of the
medical history, standardized questionnaire (App. B-111), Schilling
byssinosis grade, and the pulmonary function measurements in paragraph
(h)(2)(iii) of this section.
(ii) Medical surveillance as required in paragraph (h)(3)(i) of this
section shall be provided every six months for
[[Page 285]]
all employees in the following categories:
(A) An FEV1 of greater than 80 percent of the predicted
value, but with an FEV1 decrement of 5 percent or 200 ml. on
a first working day;
(B) An FEV1 of less than 80 percent of the predicted
value; or
(C) Where, in the opinion of the physician, any significant change
in questionnaire findings, pulmonary function results, or other
diagnostic tests have occurred.
(iii) An employee whose FEV1 is less than 60 percent of
the predicted value shall be referred to a physician for a detailed
pulmonary examination.
(iv) A comparison shall be made between the current examination
results and those of previous examinations and a determination made by
the physician as to whether there has been a significant change.
(4) Information provided to the physician. The employer shall
provide the following information to the examination physician:
(i) A copy of this regulation and its Appendices:
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's exposure level or anticipated exposure level;
(iv) A description of any personal protective equipment used or to
be used; and
(v) Information from previous medical examinations of the affected
employee which is not readily available to the examining physician.
(5) Physician's written opinion. (i) The employer shall obtain and
furnish the employee with a copy of a written opinion from the examining
physician containing the following:
(A) The results of the medical examination and tests including the
FEV1, FVC, AND FEV1/FVC ratio;
(B) The physician's opinion as to whether the employee has any
detected medical conditions which would place the employee at increased
risk of material impairment of the employee's health from exposure to
cotton dust;
(C) The physician's recommended limitations upon the employee's
exposure to cotton dust or upon the employee's use of respirators
including a determination of whether an employee can wear a negative
pressure respirator, and where the employee cannot, a determination of
the employee's ability to wear a powered air purifying respirator; and,
(D) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
which require further examination or treatment.
(ii) The written opinion obtained by the employer shall not reveal
specific findings or diagnoses unrelated to occupational exposure.
(i) Employee education and training--(1) Training program. (i) The
employer shall train each employee exposed to cotton dust in accordance
with the requirements of this section. The employer shall institute a
training program and ensure employee participation in the program.
(A) The acute and long term health hazards associated with exposure
to cotton dust;
(B) The names and descriptions of jobs and processes which could
result in exposure to cotton dust at or above the PEL.
(C) The measures, including work practices required by paragraph (g)
of this section, necessary to protect the employee from exposures in
excess of the permissible exposure limit;
(D) The purpose, proper use and limitations of respirators required
by paragraph (f) of this section;
(E) The purpose for and a description of the medical surveillance
program required by paragraph (h) of this section and other information
which will aid exposed employees in understanding the hazards of cotton
dust exposure; and
(F) The contents of this standard and its appendices.
(ii) The training program shall be provided prior to initial
assignment and shall be repeated annually for each employee exposed to
cotton dust, when job assignments or work processes change and when
employee performance indicates a need for retraining.
(2) Access to training materials. (i) Each employer shall post a
copy of this section with its appendices in a public location at the
workplace, and shall,
[[Page 286]]
upon request, make copies available to employees.
(ii) The employer shall provide all materials relating to the
employee training and information program to the Assistant Secretary and
the Director upon request.
(j) Signs. (1) The employer shall post the following warning sign in
each work area where the permissible exposure limit for cotton dust is
exceeded:
DANGER
COTTON DUST
CAUSES DAMAGE TO LUNGS
(BYSSINOSIS)
WEAR RESPIRATORY PROTECTION IN THIS AREA
(2) Prior to June 1, 2016, employers may use the following legend in
lieu of that specified in paragraph (j)(1) of this section:
WARNING
COTTON DUST WORK AREA
MAY CAUSE ACUTE OR DELAYED
LUNG INJURY
(BYSSINOSIS)
RESPIRATORS
REQUIRED IN THIS AREA
(k) Recordkeeping--(1) Exposure measurements. (i) The employer shall
establish and maintain an accurate record of all measurements required
by paragraph (d) of this section.
(ii) The record shall include:
(A) A log containing the items listed in paragraph IV (a) of
appendix A, and the dates, number, duration, and results of each of the
samples taken, including a description of the procedure used to
determine representative employee exposure;
(B) The type of protective devices worn, if any, and length of time
worn; and
(C) The names, social security numbers, job classifications, and
exposure levels of employees whose exposure the measurement is intended
to represent.
(iii) The employer shall maintain this record for at least 20 years.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate medical record for each employee subject to medical
surveillance required by paragraph (h) of this section.
(ii) The record shall include:
(A) The name and social security number and description of the
duties of the employee;
(B) A copy of the medical examination results including the medical
history, questionnaire response, results of all tests, and the
physician's recommendation;
(C) A copy of the physician's written opinion;
(D) Any employee medical complaints related to exposure to cotton
dust;
(E) A copy of this standard and its appendices, except that the
employer may keep one copy of the standard and the appendices for all
employees, provided that he references the standard and appendices in
the medical surveillance record of each employee; and
(F) A copy of the information provided to the physician as required
by paragraph (h)(4) of this section.
(iii) The employer shall maintain this record for at least 20 years.
(3) Availability. (i) The employer shall make all records required
to be maintained by paragraph (k) of this section available to the
Assistant Secretary and the Director for examination and copying.
(ii) Employee exposure measurement records and employee medical
records required by this paragraph shall be provided upon request to
employees, designated representatives, and the Assistant Secretary in
accordance with 29 CFR 1910.1020 (a) through (e) and (g) through (i).
(4) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by paragraph (k) of this section.
(ii) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.1020(h).
(l) Observation of monitoring. (1) The employer shall provide
affected employees or their designated representatives an opportunity to
observe any measuring or monitoring of employee exposure to cotton dust
conducted pursuant to paragraph (d) of this section.
(2) Whenever observation of the measuring or monitoring of employee
exposure to cotton dust requires entry into an area where the use of
personal
[[Page 287]]
protective equipment is required, the employer shall provide the
observer with and assure the use of such equipment and shall require the
observer to comply with all other applicable safety and health
procedures.
(3) Without interfering with the measurement, observers shall be
entitled to:
(i) An explanation of the measurement procedures:
(ii) An opportunity to observe all steps related to the measurement
of airborne concentrations of cotton dust performed at the place of
exposure; and
(iii) An opportunity to record the results obtained.
(m) Washed Cotton--(1) Exemptions. Cotton, after it has been washed
by the processes described in this paragraph, is exempt from all or
parts of this section as specified if the requirements of this paragraph
are met.
(2) Initial requirements. (i) In order for an employer to qualify as
exempt or partially exempt from this standard for operations using
washed cotton, the employer must demonstrate that the cotton was washed
in a facility which is open to inspection by the Assistant Secretary and
the employer must provide sufficient accurate documentary evidence to
demonstrate that the washing methods utilized meet the requirements of
this paragraph.
(ii) An employer who handles or processes cotton which has been
washed in a facility not under the employer's control and claims an
exemption or partial exemption under this paragraph, must obtain from
the cotton washer and make available at the worksite, to the Assistant
Secretary, to any affected employee, or to their designated
representative the following:
(A) A certification by the washer of the cotton of the grade of
cotton, the type of washing process, and that the batch meets the
requirements of this paragraph;
(B) Sufficient accurate documentation by the washer of the cotton
grades and washing process; and
(C) An authorization by the washer that the Assistant Secretary or
the Director may inspect the washer's washing facilities and
documentation of the process.
(3) Medical and dyed cotton. Medical grade (USP) cotton, cotton that
has been scoured, bleached and dyed, and mercerized yarn shall be exempt
from all provisions of this standard.
(4) Higher grade washed cotton. The handling or processing of cotton
classed as ``low middling light spotted or better'' (color grade 52 or
better and leaf grade code 5 or better according to the 1993 USDA
classification system) shall be exempt from all provisions of the
standard except the requirements of paragraphs (h) medical surveillance,
(k)(2) through (4) recordkeeping--medical records, and Appendices B, C,
and D of this section, if they have been washed on one of the following
systems:
(i) On a continuous batt system or a rayon rinse system including
the following conditions:
(A) With water;
(B) At a temperature of no less than 60 [deg]C;
(C) With a water-to-fiber ratio of no less than 40:1; and
(D) With the bacterial levels in the wash water controlled to limit
bacterial contamination of the cotton.
(ii) On a batch kier washing system including the following
conditions:
(A) With water;
(B) With cotton fiber mechanically opened and thoroughly prewetted
before forming the cake;
(C) For low-temperature processing, at a temperature of no less than
60 [deg]C with a water-to-fiber ratio of no less than 40:1; or, for
high-temperature processing, at a temperature of no less than 93 [deg]C
with a water-to-fiber ratio of no less than 15:1;
(D) With a minimum of one wash cycle followed by two rinse cycles
for each batch, using fresh water in each cycle, and
(E) With bacterial levels in the wash water controlled to limit
bacterial contamination of the cotton.
(5) Lower grade washed cotton. The handling and processing of cotton
of grades lower than ``low middling light spotted,'' that has been
washed as specified in paragraph (n)(4) of this section and has also
been bleached, shall be exempt from all provisions of the standard
except the requirements of paragraphs (c)(1)(ii) Permissible Exposure
[[Page 288]]
Limit, (d) Exposure Monitoring, (h) Medical Surveillance, (k)
Recordkeeping, and Appendices B, C and D of this section.
(6) Mixed grades of washed cotton. If more than one grade of washed
cotton is being handled or processed together, the requirements of the
grade with the most stringent exposure limit, medical and monitoring
requirements shall be followed.
(n) Appendices. (1) Appendices B, C, and D of this section are
incorporated as part of this section and the contents of these
appendices are mandatory.
(2) Appendix A of this section contains information which is not
intended to create any additional obligations not otherwise imposed or
to detract from any existing obligations.
(3) Appendix E of this section is a protocol which may be followed
in the validation of alternative measuring devices as equivalent to the
vertical elutriator cotton dust sampler. Other protocols may be used if
it is demonstrated that they are statistically valid, meet the
requirements in paragraph (d)(l)(iii) of this section, and are
appropriate for demonstrating equivalency.
Appendix A toSec. 1910.1043--Air Sampling and Analytical Procedures
for Determining Concentrations of Cotton Dust
i. sampling locations
The sampling procedures must be designed so that samples of the
actual dust concentrations are collected accurately and consistently and
reflect the concentrations of dust at the place and time of sampling.
Sufficient number of 6-hour area samples in each distinct work area of
the plant should be collected at locations which provide representative
samples of air to which the worker is exposed. In order to avoid filter
overloading, sampling time may be shortened when sampling in dusty
areas. Samples in each work area should be gathered simultaneously or
sequentially during a normal operating period. The daily time-weighted
average (TWA) exposure of each worker can then be determined by using
the following formula:
Summation of hours spent in each location and the dust concentration in
that location.
Total hours exposed
A time-weighted average concentration should be computed for each worker
and properly logged and maintained on file for review.
ii. sampling equipment
(a) Sampler. The instrument selected for monitoring is the Lumsden-
Lynch vertical elutriator. It should operate at a flow rate of 7.40.2 liters/minute.
The samplers should be cleaned prior to sampling. The pumps should be
monitored during sampling.
(b) Filter Holder. A three-piece cassette constructed of polystyrene
designed to hold a 37-mm diameter filter should be used. Care must be
exercised to insure that an adequate seal exists between elements of the
cassette.
(c) Filers and Support Pads. The membrane filters used should be
polyvinyl chloride with a 5-um pore size and 37-mm diameter. A support
pad, commonly called a backup pad, should be used under the filter
membrane in the field monitor cassette.
(d) Balance. A balance sensitive to 10 micrograms should be used.
(e) Monitoring equipment for use in Class III hazardous locations
must be approved for use in such locations, in accordance with the
requirements of the OSHA electrical standards in subpart S of part 1910.
iii. instrument calibration procedure
Samplers shall be calibrated when first received from the factory,
after repair, and after receiving any abuse. The samplers should be
calibrated in the laboratory both before they are used in the field and
after they have been used to collect a large number of field samples.
The primary standard, such as a spirometer or other standard calibrating
instruments such as a wet test meter or a large bubble meter or dry gas
meter, should be used. Instructions for calibration with the wet test
meter follow. If another calibration device is selected, equivalent
procedures should be used:
(a) Level wet test meter. Check the water level which should just
touch the calibration point at the left side of the meter. If water
level is low, add water 1-2 [deg]F. warmer than room temperature of till
point. Run the meter for 30 minutes before calibration;
(b) Place the polyvinyl chloride membrane filter in the filter
cassette;
(c) Assemble the calibration sampling train;
(d) Connect the wet test meter to the train.
The pointer on the meter should run clockwise and a pressure drop of not
more than 1.0 inch of water indicated. If the pressure drop is greater
than 1.0, disconnect and check the system;
(e) Operate the system for ten minutes before starting the
calibration;
(f) Check the vacuum gauge on the pump to insure that the pressure
drop across the orifice exceeds 17 inches of mercury;
(g) Record the following on calibration data sheets:
[[Page 289]]
(1) Wet test meter reading, start and finish;
(2) Elapsed time, start and finish (at least two minutes);
(3) Pressure drop at manometer;
(4) Air temperature;
(5) Barometric pressure; and
(6) Limiting orifice number;
(h) Calculate the flow rate and compare against the flow of
7.40.2 liters/minute. If flow is between these
limits, perform calibration again, average results, and record orifice
number and flow rate. If flow is not within these limits, discard or
modify orifice and repeat procedure;
(i) Record the name of the person performing the calibration, the
date, serial number of the wet test meter, and the number of the
critical orifices being calibrated.
iv. sampling procedure
(a) Sampling data sheets should include a log of:
(1) The date of the sample collection;
(2) The time of sampling;
(3) The location of the sampler;
(4) The sampler serial number;
(5) The cassette number;
(6) The time of starting and stopping the sampling and the duration
of sampling;
(7) The weight of the filter before and after sampling;
(8) The weight of dust collected (corrected for controls);
(9) The dust concentration measured;
(10) Other pertinent information; and
(11) Name of person taking sample
(b) Assembly of filter cassette should be as follows:
(1) Loosely assemble 3-piece cassette;
(2) Number cassette;
(3) Place absorbant pad in cassette;
(4) Weigh filter to an accuracy of 10 [micro]g;
(5) Place filter in cassette;
(6) Record weight of filter in log, using cassette number for
identification;
(7) Fully assemble cassette, using pressure to force parts tightly
together;
(8) Install plugs top and bottom;
(9) Put shrink band on cassette, covering joint between center and
bottom parts of cassette; and
(10) Set cassette aside until shrink band dries thoroughly.
(c) Sampling collection should be performed as follows:
(1) Clean lint out of the motor and elutriator;
(2) Install vertical elutriator in sampling locations specified
above with inlet 4\1/2\ to 5\1/2\ feet from floor (breathing zone
height);
(3) Remove top section of cassette;
(4) Install cassette in ferrule of elutriator;
(5) Tape cassette to ferrule with masking tape or similar material
for air-tight seal;
(6) Remove bottom plug of cassette and attach hose containing
critical orifice;
(7) Start elutriator pump and check to see if gauge reads above 17
in. of Hg vacuum;
(8) Record starting time, cassette number, and sampler number;
(9) At end of sampling period stop pump and record time; and
(10) Controls with each batch of samples collected, two additional
filter cassettes should be subjected to exactly the same handling as the
samples, except that they are not opened. These control filters should
be weighed in the same manner as the sample filters.
Any difference in weight in the control filters would indicate that the
procedure for handling sample filters may not be adequate and should be
evaluated to ascertain the cause of the difference, whether and what
necessary corrections must be made, and whether additional samples must
be collected.
(d) Shipping. The cassette with samples should be collected, along
with the appropriate number of blanks, and shipped to the analytical
laboratory in a suitable container to prevent damage in transit.
(e) Weighing of the sample should be achieved as follows:
(1) Remove shrink band;
(2) Remove top and middle sections of cassette and botton plug;
(3) Remove filter from cassette and weigh to an accuracy of 10
[micro]g; and
(4) Record weight in log against original weight
(f) Calculation of volume of air sampled should be determined as
follows:
(1) From starting and stopping times of sampling period, determine
length of time in minutes of sampling period; and
(2) Multiply sampling time in minutes by flow rate of critical
orifice in liters per minute and divide by 1000 to find air quantity in
cubic meters.
(g) Calculation of Dust Concentrations should be made as follows:
(1) Substract weight of clean filter from dirty filter and apply
control correction to find actual weight of sample. Record this weight
(in [micro]g) in log; and
(2) Divide mass of sample in [micro]g by air volume in cubic meters
to find dust concentration in [micro]g/m. Record in log.
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Appendix D toSec. 1910.1043--Pulmonary Function Standards for Cotton
Dust Standard
The spirometric measurements of pulmonary function shall conform to
the following minimum standards, and these standards are not intended to
preclude additional testing or alternate methods which can be determined
to be superior.
i. apparatus
a. The instrument shall be accurate to within 50 milliliters or within 3 percent
of reading, whichever is greater.
b. The instrument should be capable of measuring vital capacity from
0 to 7 liters BTPS.
c. The instrument shall have a low inertia and offer low resistance
to airflow such that the resistance to airflow at 12 liters per second
must be less than 1.5 cm H2 O/(liter/sec).
d. The zero time point for the purpose of timing the FEV1
shall be determined by extrapolating the steepest portion of the volume
time curve back to the maximal inspiration volume (1, 2, 3, 4) or by an
equivalent method.
e. Instruments incorporating measurements of airflow to determine
volume shall conform to the same volume accuracy stated in (a) of this
section when presented with flow rates from at least 0 to 12 liters per
second.
f. The instrument or user of the instrument must have a means of
correcting volumes to body temperature saturated with water vapor (BTPS)
under conditions of varying ambient spirometer temperatures and
barometric pressures.
g. The instrument used shall provide a tracing or display of either
flow versus volume or volume versus time during the entire forced
expiration. A tracing or display is necessary to determine whether the
patient has performed the test properly. The tracing must be stored and
available for recall and must be of sufficient size that hand
measurements may be made within requirement of paragraph (a) of this
section. If a paper record is made it must have a paper speed of at
least 2 cm/sec and a volume sensitivity of at least 10.0 mm of chart per
liter of volume.
h. The instrument shall be capable of accumulating volume for a
minimum of 10 seconds and shall not stop accumulating volume before (1)
the volume change for a 0.5 second interval is less than 25 milliliters,
or (2) the flow is less than 50 milliliters per second for a 0.5 second
interval.
i. The forced vital capacity (FVC) and forced expiratory volume in 1
second (FEV1.0) measurements shall comply with the accuracy
requirements stated in paragraph (a) of this section. That is, they
should be accurately measured to within 50 ml or
within 3 percent of reading, whichever is greater.
j. The instrument must be capable of being calibrated in the field
with respect to the FEV1 and FVC. This calibration of the
FEV1 and FVC may be either directly or indirectly through
volume and time base measurements. The volume calibration source should
provide a volume displacement of at least 2 liters and should be
accurate to within 30 milliliters.
ii. technique for measurement of forced vital capacity maneuver
a. Use of a nose clip is recommended but not required. The
procedures shall be explained in simple terms to the patient who shall
be instructed to loosen any tight clothing and stand in front of the
apparatus. The subject may sit, but care should be taken on repeat
testing that the same position be used and, if possible, the same
spirometer. Particular attention shall be given to insure that the chin
is slightly elevated with the neck slightly extended. The patient shall
be instructed to make a full inspiration from a normal breathing pattern
and then blow into the apparatus, without interruption, as hard, fast,
and completely as possible. At least three forced expirations shall be
carried out. During the maneuvers, the patient shall be observed for
compliance with instruction. The expirations shall be checked visually
for reproducibility from flow-volume or volume-time tracings or
displays. The following efforts shall be judged unacceptable when the
patient:
1. Has not reached full inspiration preceding the forced expiration,
2. Has not used maximal effort during the entire forced expiration,
3. Has not continued the expiration for at least 5 seconds or until
an obvious plateau in the volume time curve has occurred,
4. Has coughed or closed his glottis,
5. Has an obstructed mouthpiece or a leak around the mouthpiece
(obstruction due to tongue being placed in front of mouthpiece, false
teeth falling in front of mouthpiece, etc.)
6. Has an unsatisfactory start of expiration, one characterized by
excessive hesitation (or false starts), and therefore not allowing back
extrapolation of time 0 (extrapolated volume on the volume time tracing
must be less than 10 percent of the FVC.)
7. Has an excessive variability between the three acceptable curves.
The variation between the two largest FVC's and FEV1's of the
three satisfactory tracings should not exceed 10 percent or 100 milliliters, whichever is greater.
b. Periodic and routine recalibration of the instrument or method
for recording FVC and FEV1.0 should be performed using a
syringe or other volume source of at least 2 liters.
[[Page 308]]
iii. interpretation of spirogram
a. The first step in evaluating a spirogram should be to determine
whether or not the patient has performed the test properly or as
described in II above. From the three satisfactory tracings, the forced
vital capacity (FVC) and forced expiratory volume in 1 second
(FEV1.0) shall be measured and recorded. The largest observed
FVC and largest observed FEV1 shall be used in the analysis
regardless of the curve(s) on which they occur.
b. The following guidelines are recommended by NIOSH for the
evaluation and management of workers exposed to cotton dust. It is
important to note that employees who show reductions in FEV1/
FVC ratio below .75 or drops in Monday FEV1 of 5 percent or
greater on their initial screening exam, should be re-evaluated within a
month of the first exam. Those who show consistent decrease in lung
function, as shown on the following table, should be managed as
recommended.
iv. qualifications of personnel administering the test
Technicians who perform pulmonary function testing should have the
basic knowledge required to produce meaningful results. Training
consisting of approximately 16 hours of formal instruction should cover
the following areas.
a. Basic physiology of the forced vital capacity maneuver and the
determinants of airflow limitation with emphasis on the relation to
reproducibility of results.
b. Instrumentation requirements including calibration procedures,
sources of error and their correction.
c. Performance of the testing including subject coaching,
recognition of improperly performed maneuvers and corrective actions.
d. Data quality with emphasis on reproducibility.
e. Actual use of the equipment under supervised conditions.
f. Measurement of tracings and calculations of results.
Appendix E toSec. 1910.1043--Vertical Elutriator Equivalency Protocol
a. Samples to be taken--In order to ascertain equivalency, it is
necessary to collect a total of 100 samples from at least 10 sites in a
mill. That is, there should be 10 replicate readings at each of 10
sites. The sites should represent dust levels which vary over the
allowable range of 0.5 to 2 times the permissible exposure limit. Each
sample requires the use of two vertical elutriators (VE's) and at least
one but not more than two alternative devices (AD's). Thus, the end
result is 200 VE readings and either 100 or 200 AD readings. The 2 VE
readings and the 1 or 2 AD readings at each time and site must be made
simultaneously. That is, the two VE's and one or two AD's must be
arranged together in such a way that they are measuring essentially the
same dust levels.
b. Data averaging--The two VE readings taken at each site are then
averaged. These averages are to be used as the 100 VE readings. If two
alternate devices were used, their test results are also averaged. Thus,
after this step is accomplished, there will be 100 VE readings and 100
AD readings.
c. Differences--For each of the 100 sets of measurements (VE and AD)
the difference is obtained as the average VE reading minus the AD
reading. Call these differences Di. Thus, we have.
Di = VEi - ADi, i = 1,2, . . . ,100 (1)
Next we compute the arithmetic mean and standard deviations of the
differences, using equations (2) and (3), respectively.
[GRAPHIC] [TIFF OMITTED] TC28OC91.038
where N equals the number of differences (100 in this case),
XD is the arithmetic mean and SD is the standard
deviation.
We next calculate the critical value as
T=KSD+[verbar]XD[verbar] where K=1.87, based on
100 samples.
d. Equivalency test. The next step is to obtain the average of the
100 VE readings. This is obtained by equation (4)
[GRAPHIC] [TIFF OMITTED] TC28OC91.039
We next multiply 0.25 by XVE. If T <= 0.25
XVE, we can say that the alternate device has passed the
equivalency test.
[43 FR 27394, June 23, 1978; 43 FR 35035, Aug. 8, 1978, as amended at 45
FR 67340, Oct. 10, 1980; 50 FR 51173, Dec. 13, 1985; 51 FR 24325, July
3, 1986; 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13, 1996; 63 FR
1290, Jan. 8, 1998; 65 FR 76567, Dec. 7, 2000; 70 FR 1142, Jan. 5, 2005;
71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR
75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17782, Mar. 26,
2012]
Sec. 1910.1044 1,2-dibromo-3-chloropropane.
(a) Scope and application. (1) This section applies to occupational
exposure to 1,2-dibromo-3-chloropropane (DBCP).
(2) This section does not apply to:
[[Page 309]]
(i) Exposure to DBCP which results solely from the application and
use of DBCP as a pesticide; or
(ii) The storage, transportation, distribution or sale of DBCP in
intact containers sealed in such a manner as to prevent exposure to DBCP
vapors or liquid, except for the requirements of paragraphs (i), (n) and
(o) of this section.
(b) Definitions. Authorized person means any person required by his
duties to be present in regulated areas and authorized to do so by his
employer, by this section, or by the Act. Authorized person also
includes any person entering such areas as a designated representative
of employees exercising an opportunity to observe employee exposure
monitoring.
DBCP means 1,2-dibromo-3-chloropropane, Chemical Abstracts Service
Registry Number 96-12-8, and includes all forms of DBCP.
Director means the Director, National Institute for Occupational
Safety and Health, U.S. Department of Health and Human Services, or
designee.
Emergency means any occurrence such as, but not limited to equipment
failure, rupture of containers, or failure of control equipment which
may, or does, result in an unexpected release of DBCP.
OSHA Area Office means the Area Office of the Occupational Safety
and Health Administration having jurisdiction over the geographic area
where the affected workplace is located.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
(c) Permissible exposure limit--(1) Inhalation. The employer shall
assure that no employee is exposed to an airborne concentration of DBCP
in excess of 1 part DBCP per billion parts of air (ppb) as an 8-hour
time-weighted average.
(2) Dermal and eye exposure. The employer shall assure that no
employee is exposed to eye or skin contact with DBCP.
(d) [Reserved]
(e) Regulated areas. (1) The employer shall establish, within each
place of employment, regulated areas wherever DBCP concentrations are in
excess of the permissible exposure limit.
(2) The employer shall limit access to regulated areas to authorized
persons.
(f) Exposure monitoring--(1) General. (i) Determinations of airborne
exposure levels shall be made from air samples that are representative
of each employee's exposure to DBCP over an 8-hour period.
(ii) For the purposes of this paragraph, employee exposure is that
exposure which would occur if the employee were not using a respirator.
(2) Initial. Each employer who has a place of employment in which
DBCP is present, shall monitor each workplace and work operation to
accurately determine the airborne concentrations of DBCP to which
employees may be exposed.
(3) Frequency. (i) If the monitoring required by this section
reveals employee exposures to be at or below the permissible exposure
limit, the employer must repeat these measurements at least every 6
months.
(ii) If the monitoring required by this section reveals employee
exposures to be in excess of the permissible exposure limit, the
employer must repeat these measurements for each such employee at least
quarterly. The employer must continue quarterly monitoring until at
least two consecutive measurements, taken at least seven (7) days apart,
are at or below the permissible exposure limit. Thereafter the employer
must monitor at least every 6 months.
(4) Additional. Whenever there has been a production, process,
control, or personnel change which may result in any new or additional
exposure to DBCP, or whenever the employer has any reason to suspect new
or additional exposures to DBCP, the employer shall monitor the
employees potentially affected by such change for the purpose of
redetermining their exposure.
(5) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each employee of these results either individually
in writing or by posting the results in an appropriate location that is
accessible to employees.
(ii) Whenever the results indicate that employee exposure exceeds
the
[[Page 310]]
permissible exposure limit, the employer shall include in the written
notice a statement that the permissible exposure limit was exceeded and
a description of the corrective action being taken to reduce exposure to
or below the permissible exposure limit.
(6) Accuracy of measurement. The employer shall use a method of
measurement which has an accuracy, to a confidence level of 95 percent,
of not less than plus or minus 25 percent for concentrations of DBCP at
or above the permissible exposure limit.
(g) Methods of compliance--(1) Priority of compliance methods. The
employer shall institute engineering and work practice controls to
reduce and maintain employee exposures to DBCP at or below the
permissible exposure limit, except to the extent that the employer
establishes that such controls are not feasible. Where feasible
engineering and work practice controls are not sufficient to reduce
employee exposures to within the permissible exposure limit, the
employer shall nonetheless use them to reduce exposures to the lowest
level achievable by these controls, and shall supplement them by use of
respiratory protection.
(2) Compliance program. (i) The employer shall establish and
implement a written program to reduce employee exposures to DBCP to or
below the permissible exposure limit solely by means of engineering and
work practice controls as required by paragraph (g)(1) of this section.
(ii) The written program shall include a detailed schedule for
development and implementation of the engineering and work practice
controls. These plans must be revised at least annually to reflect the
current status of the program.
(iii) Written plans for these compliance programs shall be submitted
upon request to the Assistant Secretary and the Director, and shall be
available at the worksite for examination and copying by the Assistant
Secretary, the Director, and any affected employee or designated
representative of employees.
(iv) The employer shall institute and maintain at least the controls
described in his most recent written compliance program.
(h) Respiratory protection--(1) General. For employees who are
required to use respirators by this section, the employer must provide
each employee an appropriate respirator that complies with the
requirements of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Maintenance and repair activities for which engineering and
work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the permissible exposure limit.
(iv) Emergencies.
(2) Respirator program. The employer must implement a respiratory
protection program in accordance withSec. 1910.134(b) through (d)
(except (d)(1)(iii)), and (f) through (m), which covers each employee
required by this section to use a respirator.
(3) Respirator selection. Employers must:
(i) Select, and provide to employees, the appropriate atmosphere-
supplying respirator specified in paragraph (d)(3)(i)(A) of 29 CFR
1910.134.
(ii) Provide employees with one of the following respirator options
to use for entry into, or escape from, unknown DBCP concentrations:
(A) A combination respirator that includes a supplied-air respirator
with a full facepiece operated in a pressure-demand or other positive-
pressure or continuous-flow mode, as well as an auxiliary self-contained
breathing apparatus (SCBA) operated in a pressure-demand or positive-
pressure mode.
(B) An SCBA with a full facepiece operated in a pressure-demand or
other positive-pressure mode.
(i) Emergency situations--(1) Written plans. (i) A written plan for
emergency situations shall be developed for each workplace in which DBCP
is present.
(ii) Appropriate portions of the plan shall be implemented in the
event of an emergency.
(2) Employees engaged in correcting emergency conditions shall be
equipped as required in paragraphs (h) and (j) of
[[Page 311]]
this section until the emergency is abated.
(3) Evacuation. Employees not engaged in correcting the emergency
shall be removed and restricted from the area and normal operations in
the affected area shall not be resumed until the emergency is abated.
(4) Alerting employees. Where there is a possibility of employee
exposure to DBCP due to the occurrence of an emergency, a general alarm
shall be installed and maintained to promptly alert employees of such
occurrences.
(5) Medical surveillance. For any employee exposed to DBCP in an
emergency situation, the employer shall provide medical surveillance in
accordance with paragraph (m)(6) of this section.
(6) Exposure monitoring. (i) Following an emergency, the employer
shall conduct monitoring which complies with paragraph (f) of this
section.
(ii) In workplaces not normally subject to periodic monitoring, the
employer may terminate monitoring when two consecutive measurements
indicate exposures below the permissible exposure limit.
(j) Protective clothing and equipments--(1) Provision and use. Where
there is any possibility of eye or dermal contact with liquid or solid
DBCP, the employer shall provide, at no cost to the employee, and assure
that the employee wears impermeable protective clothing and equipment to
protect the area of the body which may come in contact with DBCP. Eye
and face protection shall meet the requirements ofSec. 1910.133 of
this part.
(2) Removal and storage. (i) The employer shall assure that
employees remove DBCP contaminated work clothing only in change rooms
provided in accordance with paragraph (l) (1) of this section.
(ii) The employer shall assure that employees promptly remove any
protective clothing and equipment which becomes contaminated with DBCP-
containing liquids and solids. This clothing shall not be reworn until
the DBCP has been removed from the clothing or equipment.
(iii) The employer shall assure that no employee takes DBCP
contaminated protective devices and work clothing out of the change
room, except those employees authorized to do so for the purpose of
laundering, maintenance, of disposal.
(iv) DBCP-contaminated protective devices and work clothing shall be
placed and stored in closed containers which prevent dispersion of the
DBCP outside the container.
(v) Containers of DBCP-contaminated protective devices or work
clothing which are to be taken out of change rooms or the workplace for
cleaning, maintenance or disposal shall bear labels with the following
information: CONTAMINATED WITH 1,2-Dibromo-3-chloropropane (DBCP), MAY
CAUSE CANCER.
(3) Cleaning and replacement. (i) The employer shall clean, launder,
repair, or replace protective clothing and equipment required by this
paragraph to maintain their effectiveness. The employer shall provide
clean protective clothing and equipment at least daily to each affected
employee.
(ii) The employer shall inform any person who launders or clean
DBCP-contaminated protective clothing or equipment of the potentially
harmful effects of exposure to DBCP.
(iii) The employer shall prohibit the removal of DBCP from
protective clothing and equipment by blowing or shaking.
(k) Housekeeping--(1) Surfaces. (i) All workplace surfaces shall be
maintained free of visible accumulations of DBCP.
(ii) Dry sweeping and the use of compressed air for the cleaning of
floors and other surfaces is prohibited where DBCP dusts or liquids are
present.
(iii) Where vacuuming methods are selected to clean floors and other
surfaces, either portable units or a permanent system may be used.
(a) If a portable unit is selected, the exhaust shall be attached to
the general workplace exhaust ventilation system or collected within the
vacuum unit, equipped with high efficiency filters or other appropriate
means of contaminant removal, so that DBCP is not reintroduced into the
workplace air; and
(b) Portable vacuum units used to collect DBCP may not be used for
other cleaning purposes and shall be labeled
[[Page 312]]
as prescribed by paragraph (j)(2)(v) of this section.
(iv) Cleaning of floors and other surfaces contaminated with DBCP-
containing dusts shall not be performed by washing down with a hose,
unless a fine spray has first been laid down.
(2) Liquids. Where DBCP is present in a liquid form, or as a
resultant vapor, all containers or vessels containing DBCP shall be
enclosed to the maximum extent feasible and tightly covered when not in
use.
(3) Waste disposal. DBCP waste scrap, debris, containers or
equipment, shall be disposed of in sealed bags or other closed
containers which prevent dispersion of DBCP outside the container.
(l) Hygiene facilities and practices--(1) Change rooms. The employer
shall provide clean change rooms equipped with storage facilities for
street clothes and separate storage facilities for protective clothing
and equipment whenever employees are required to wear protective
clothing and equipment in accordance with paragraphs (h) and (j) of this
section.
(2) Showers. (i) The employer shall assure that employees working in
the regulated area shower at the end of the work shift.
(ii) The employer shall assure that employees whose skin becomes
contaminated with DBCP-containing liquids or solids immediately wash or
shower to remove any DBCP from the skin.
(iii) The employer shall provide shower facilities in accordance
with 29 CFR 1910.141(d)(3).
(3) Lunchrooms. The employer shall provide lunchroom facilities
which have a temperature controlled, positive pressure, filtered air
supply, and which are readily accessible to employees working in
regulated areas.
(4) Lavatories. (i) The employer shall assure that employees working
in the regulated area remove protective clothing and wash their hands
and face prior to eating.
(ii) The employer shall provide a sufficient number of lavatory
facilities which comply with 29 CFR 1910.141(d) (1) and (2).
(5) Prohibition of activities in regulated areas. The employer shall
assure that, in regulated areas, food or beverages are not present or
consumed, smoking products and implements are not present or used, and
cosmetics are not present or applied.
(m) Medical surveillance--(1) General. (i) The employer shall make
available a medical surveillance program for employees who work in
regulated areas and employees who are subjected to DBCP exposures in an
emergency situation.
(ii) All medical examinations and procedures shall be performed by
or under the supervision of a licensed physician, and shall be provided
without cost to the employee.
(2) Frequency and content. At the time of initial assignment, and
annually thereafter, the employer shall provide a medical examination
for employees who work in regulated areas, which includes at least the
following:
(i) A medical and occupational history including reproductive
history.
(ii) A physical examination, including examination of the genito-
urinary tract, testicle size and body habitus, including a determination
of sperm count.
(iii) A serum specimen shall be obtained and the following
determinations made by radioimmunoassay techniques utilizing National
Institutes of Health (NIH) specific antigen or one of equivalent
sensitivity:
(a) Serum follicle stimulating hormone (FSH);
(b) Serum luteinizing hormone (LH); and
(c) Serum total estrogen (females).
(iv) Any other tests deemed appropriate by the examining physician.
(3) Additional examinations. If the employee for any reason develops
signs or symptoms commonly associated with exposure to DBCP, the
employer shall provide the employee with a medical examination which
shall include those elements considered appropriate by the examining
physician.
(4) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this regulation and its appendices;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
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(iii) The level of DBCP to which the employee is exposed; and
(iv) A description of any personal protective equipment used or to
be used.
(5) Physician's written opinion. (i) For each examination under this
section, the employer shall obtain and provide the employee with a
written opinion from the examining physician which shall include:
(a) The results of the medical tests performed;
(b) The physician's opinion as to whether the employee has any
detected medical condition which would place the employee at an
increased risk of material impairment of health from exposure to DBCP;
and
(c) Any recommended limitations upon the employee's exposure to DBCP
or upon the use of protective clothing and equipment such as
respirators.
(ii) The employer shall instruct the physician not to reveal in the
written opinion specific findings or diagnoses unrelated to occupational
exposure.
(6) Emergency situations. If the employee is exposed to DBCP in an
emergency situation, the employer shall provide the employee with a
sperm count test as soon as practicable, or, if the employee has been
vasectionized or is unable to produce a semen specimen, the hormone
tests contained in paragraph (m)(2)(iii) of this section. The employer
shall provide these same tests three months later.
(n) Employee information and training--(1) Training program. (i) The
employer shall train each employee who may be exposed to DBCP in
accordance with the requirements of this section. The employer shall
institute a training program and ensure employee participation in the
program.
(ii) The employer shall assure that each employee is informed of the
following:
(a) The information contained in appendix A;
(b) The quantity, location, manner of use, release or storage of
DBCP and the specific nature of operations which could result in
exposure to DBCP as well as any necessary protective steps;
(c) The purpose, proper use, and limitations of respirators;
(d) The purpose and description of the medical surveillance program
required by paragraph (m) of this section; and
(e) A review of this standard, including appendices.
(2) Access to training materials. (i) The employer shall make a copy
of this standard and its appendices readily available to all affected
employees.
(ii) The employer shall provide, upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(o) Communication of hazards--(1) Hazard communication--general. (i)
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard Communication Standard (HCS)
(Sec. 1910.1200) for DBCP.
(ii) In classifying the hazards of DBCP at least the following
hazards are to be addressed: Cancer; reproductive effects; liver
effects; kidney effects; central nervous system effects; skin, eye and
respiratory tract irritation; and acute toxicity effects.
(iii) Employers shall include DBCP in the hazard communication
program established to comply with the HCS (Sec. 1910.1200). Employers
shall ensure that each employee has access to labels on containers of
DBCP and to safety data sheets, and is trained in accordance with the
requirements of HCS and paragraph (n) of this section.
(iv) The employer shall ensure that no statement appears on or near
any sign or label required by this paragraph (o) which contradicts or
detracts from the meaning of the required sign or label.
(2) Signs. (i) The employer shall post signs to clearly indicate all
regulated areas. These signs shall bear the legend:
DANGER
1,2-Dibromo-3-chloropropane
MAY CAUSE CANCER
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(ii) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (o)(2) of this section:
DANGER
[[Page 314]]
1,2-Dibromo-3-chloropropane
(Insert appropriate trade or common names)
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATOR REQUIRED
(3) Labels. (i) Where DBCP or products containing DBCP are sold,
distributed or otherwise leave the employer's workplace bearing
appropriate labels required by EPA under the regulations in 40 CFR Part
162, the labels required by this paragraph (o)(3) need not be affixed.
(ii) The employer shall ensure that the precautionary labels
required by this paragraph (o)(3) are readily visible and legible.
(iii) Prior to June 1, 2015, employers may include the following
information on containers of DBCP or products containing DBCP, DBCP-
contaminated protective devices or work clothing or DBCP-contaminated
portable vacuums in lieu of the labeling requirements in paragraphs
(j)(2)(v), (k)(l)(iii)(b) and (o)(1)(i) of this section:
DANGER
1,2-Dibromo-3-chloropropane
CANCER HAZARD
(p) Recordkeeping--(1) Exposure monitoring. (i) The employer shall
establish and maintain an accurate record of all monitoring required by
paragraph (f) of this section.
(ii) This record shall include:
(a) The dates, number, duration and results of each of the samples
taken, including a description of the sampling procedure used to
determine representative employee exposure;
(b) A description of the sampling and analytical methods used;
(c) Type of respiratory protective devices worn, if any; and
(d) Name, social security number, and job classification of the
employee monitored and of all other employees whose exposure the
measurement is intended to represent.
(iii) The employer shall maintain this record for at least 40 years
or the duration of employment plus 20 years, whichever is longer.
(2) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance required by paragraph (m) of this section.
(ii) This record shall include:
(a) The name and social security number of the employee;
(b) A copy of the physician's written opinion;
(c) Any employee medical complaints related to exposure to DBCP;
(d) A copy of the information provided the physician as required by
paragraphs (m)(4)(ii) through (m)(4)(iv) of this section; and
(e) A copy of the employee's medical and work history.
(iii) The employer shall maintain this record for at least 40 years
or the duration of employment plus 20 years, whichever is longer.
(3) Availability. (i) The employer shall assure that all records
required to be maintained by this section be made available upon request
to the Assistant Secretary and the Director for examination and copying.
(ii) Employee exposure monitoring records and employee medical
records required by this paragraph shall be provided upon request to
employees, designated representatives, and the Assistant Secretary in
accordance with 29 CFR 1910.1020 (a) through (e) and (g) through (i).
(4) Transfer of records. (i) If the employer ceases to do business,
the successor employer shall receive and retain all records required to
be maintained by paragraph (p) of this section for the prescribed
period.
(ii) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.1020(h).
(q) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees, or their designated
representatives, with an opportunity to observe any monitoring of
employee exposure to DBCP required by this section.
(2) Observation procedures. (i) Whenever observation of the
measuring or monitoring of employee exposure to DBCP requires entry into
an area where the use of protective clothing or equipment is required,
the employer shall provide the observer with personal protective
clothing or equipment required to be worn by employees working in the
area, assure the use of such clothing and equipment, and require the
observer to comply with all
[[Page 315]]
other applicable safety and health procedures.
(ii) Without interfering with the monitoring or measurement,
observers shall be entitled to:
(a) Receive an explanation of the measurement procedures;
(b) Observe all steps related to the measurement of airborne
concentrations of DBCP performed at the place of exposure; and
(c) Record the results obtained.
(r) Appendices. The information contained in the appendices is not
intended, by itself, to create any additional obligations not otherwise
imposed or to detract from any existing obligation.
Appendix A toSec. 1910.1044--Substance Safety Data Sheet For DBCP
i. Substance Identification
A. Synonyms and trades names: DBCP; Dibromochloropropane; Fumazone
(Dow Chemical Company TM); Nemafume; Nemagon (Shell Chemical Co. TM);
Nemaset; BBC 12; and OS 1879.
B. Permissible exposure:
1. Airborne. 1 part DBCP vapor per billion parts of air (1 ppb);
time-weighted average (TWA) for an 8-hour workday.
2. Dermal. Eye contact and skin contact with DBCP are prohibited.
C. Appearance and odor: Technical grade DBCP is a dense yellow or
amber liquid with a pungent odor. It may also appear in granular form,
or blended in varying concentrations with other liquids.
D. Uses: DBCP is used to control nematodes, very small worm-like
plant parasites, on crops including cotton, soybeans, fruits, nuts,
vegetables and ornamentals.
ii. Health Hazard Data
A. Routes of entry: Employees may be exposed:
1. Through inhalation (breathing);
2. Through ingestion (swallowing);
3. Skin contact; and
4. Eye contact.
B. Effects of exposure:
1. Acute exposure. DBCP may cause drowsiness, irritation of the
eyes, nose, throat and skin, nausea and vomiting. In addition,
overexposure may cause damage to the lungs, liver or kidneys.
2. Chronic exposure. Prolonged or repeated exposure to DBCP has been
shown to cause sterility in humans. It also has been shown to produce
cancer and sterility in laboratory animals and has been determined to
constitute an increased risk of cancer in man.
3. Reporting Signs and Symptoms. If you develop any of the above
signs or symptoms that you think are caused by exposure to DBCP, you
should inform your employer.
iii. Emergency First Aid Procedures
A. Eye exposure. If DBCP liquid or dust containing DBCP gets into
your eyes, wash your eyes immediately with large amounts of water,
lifting the lower and upper lids occasionally. Get medical attention
immediately. Contact lenses should not be worn when working with DBCP.
B. Skin exposure. If DBCP liquids or dusts containing DBCP get on
your skin, immediately wash using soap or mild detergent and water. If
DBCP liquids or dusts containing DBCP penetrate through your clothing,
remove the clothing immediately and wash. If irritation is present after
washing get medical attention.
C. Breathing. If you or any person breathe in large amounts of DBCP,
move the exposed person to fresh air at once. If breathing has stopped,
perform artificial respiration. Do not use mouth-to-mouth. Keep the
affected person warm and at rest. Get medical attention as soon as
possible.
D. Swallowing. When DBCP has been swallowed and the person is
conscious, give the person large amounts of water immediately. After the
water has been swallowed, try to get the person to vomit by having him
touch the back of his throat with his finger. Do not make an unconscious
person vomit. Get medical attention immediately.
E. Rescue. Notify someone. Put into effect the established emergency
rescue procedures. Know the locations of the emergency rescue equipment
before the need arises.
iv. Respirators and Protective Clothing
A. Respirators. You may be required to wear a respirator in
emergencies and while your employer is in the process of reducing DBCP
exposures through engineering controls. If respirators are worn, they
must have a National Institute for Occupational Safety and Health
(NIOSH) approval label (Older respirators may have a Bureau of Mines
Approval label). For effective protection, a respirator must fit your
face and head snugly. The respirator should not be loosened or removed
in work situations where its use is required. DBCP does not have a
detectable odor except at 1,000 times or more above the permissible
exposure limit. If you can smell DBCP while wearing a respirator, the
respirator is not working correctly; go immediately to fresh air. If you
experience difficulty breathing while wearing a respirator, tell your
employer.
B. Protective clothing. When working with DBCP you must wear for
your protection impermeable work clothing provided by your employer.
(Standard rubber and neoprene
[[Page 316]]
protective clothing do not offer adequate protection).
DBCP must never be allowed to remain on the skin. Clothing and shoes
must not be allowed to become contaminated with DBCP, and if they do,
they must be promptly removed and not worn again until completely free
of DBCP. Turn in impermeable clothing that has developed leaks for
repair or replacement.
C. Eye protection. You must wear splash-proof safety goggles where
there is any possibility of DBCP liquid or dust contacting your eyes.
v. Precautions for Safe Use, Handling, and Storage
A. DBCP must be stored in tightly closed containers in a cool, well-
ventilated area.
B. If your work clothing may have become contaminated with DBCP, or
liquids or dusts containing DBCP, you must change into uncontaminated
clothing before leaving the work premises.
C. You must promptly remove any protective clothing that becomes
contaminated with DBCP. This clothing must not be reworn until the DBCP
is removed from the clothing.
D. If your skin becomes contaminated with DBCP, you must immediately
and thoroughly wash or shower with soap or mild detergent and water to
remove any DBCP from your skin.
E. You must not keep food, beverages, cosmetics, or smoking
materials, nor eat or smoke, in regulated areas.
F. If you work in a regulated area, you must wash your hands
thoroughly with soap or mild detergent and water, before eating, smoking
or using toilet facilities.
G. If you work in a regulated area, you must remove any protective
equipment or clothing before leaving the regulated area.
H. Ask your supervisor where DBCP is used in your work area and for
any additional safety and health rules.
vi. Access to Information
A. Each year, your employer is required to inform you of the
information contained in this Substance Safety Data Sheet for DBCP. In
addition, your employer must instruct you in the safe use of DBCP,
emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being
exposed to DBCP. You or your representative have the right to observe
employee exposure measurements and to record the result obtained. Your
employer is required to inform you of your exposure. If your employer
determines that you are being overexposed, he is required to inform you
of the actions which are being taken to reduce your exposure.
C. Your employer is required to keep records of your exposure and
medical examinations. Your employer is required to keep exposure and
medical data for at least 40 years or the duration of your employment
plus 20 years, whichever is longer.
D. Your employer is required to release exposure and medical records
to you, your physician, or other individual designated by you upon your
written request.
Appendix B toSec. 1910.1044--Substance Technical Guidelines for DBCP
i. Physical and Chemical Data
A. Substance Identification
1. Synonyms: 1,2-dibromo-3-chloropropane; DBCP, Fumazone; Nemafume;
Nemagon; Nemaset; BBC 12; OS 1879. DBCP is also included in agricultural
pesticides and fumigants which include the phrase ``Nema--'' in their
name.
2. Formula: C3H5Br2 C1.
3. Molecular Weight: 236.
B. Physical Data:
1. Boiling point (760 mm HG): 195C (383F)
2. Specific gravity (water=1): 2.093.
3. Vapor density (air=1 at boiling point of DBCP): Data not
available.
4. Melting point: 6C (43F).
5. Vapor pressure at 20C (68F): 0.8 mm Hg
6. Solubility in water: 1000 ppm.
7. Evaporation rate (Butyl Acetate=1): very much less than 1.
8. Appearance and odor: Dense yellow or amber liquid with a pungent
odor at high concentrations. Any detectable odor of DBCP indicates
overexposure.
ii. Fire Explosion and Reactivity Hazard Data
A. Fire
1. Flash point: 170F (77C)
2. Autoignition temperature: Data not available.
3. Flammable limits in air, percent by volume: Data not available.
4. Extinguishing media: Carbon dioxide, dry chemical.
5. Special fire-fighting procedures: Do not use a solid stream of
water since a stream will scatter and spread the fire. Use water spray
to cool containers exposed to a fire.
6. Unusual fire and explosion hazards: None known.
7. For purposes of complying with the requirements ofSec.
1910.106, liquid DBCP is classified as a Category 4 flammable liquid.
8. For the purpose of complying withSec. 1910.309, the
classification of hazardous locations as described in article 500 of the
National Electrical Code for DBCP shall be Class I, Group D.
9. For the purpose of compliance withSec. 1910.157, DBCP is
classified as a Class B fire hazard.
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10. For the purpose of compliance withSec. 1910.178, locations
classified as hazardous locations due to the presence of DBCP shall be
Class I, Group D.
11. Sources of ignition are prohibited where DBCP presents a fire or
explosion hazard.
B. Reactivity
1. Conditions contributing to instability: None known.
2. Incompatibilities: Reacts with chemically active metals, such as
aluminum, magnesium and tin alloys.
3. Hazardous decomposition products: Toxic gases and vapors (such as
HBr, HCl and carbon monoxide) may be released in a fire involving DBCP.
4. Special precautions: DBCP will attack some rubber materials and
coatings.
iii. Spill, Leak and Disposal Procedures
A. If DBCP is spilled or leaked, the following steps should be
taken:
1. The area should be evacuated at once and re-entered only after
thorough ventilation.
2. Ventilate area of spill or leak.
3. If in liquid form, collect for reclamation or absorb in paper,
vermiculite, dry sand, earth or similar material.
4. If in solid form, collect spilled material in the most convenient
and safe manner for reclamation or for disposal.
B. Persons not wearing protective equipment must be restricted from
areas of spills or leaks until cleanup has been completed.
C. Waste Disposal Methods:
1. For small quantities of liquid DBCP, absorb on paper towels,
remove to a safe place (such as a fume hood) and burn the paper. Large
quantities can be reclaimed or collected and atomized in a suitable
combustion chamber equipped with an appropriate effluent gas cleaning
device. If liquid DBCP is absorbed in vermiculite, dry sand, earth or
similar material and placed in sealed containers it may be disposed of
in a State-approved sanitary landfill.
2. If in solid form, for small quantities, place on paper towels,
remove to a safe place (such as a fume hood) and burn. Large quantities
may be reclaimed. However, if this is not practical, dissolve in a
flammable solvent (such as alcohol) and atomize in a suitable combustion
chamber equipped with an appropriate effluent gas cleaning device. DBCP
in solid form may also be disposed in a state-approved sanitary
landfill.
iv. Monitoring and Measurement Procedures
A. Exposure above the permissible exposure limit.
1. Eight Hour Exposure Evaluation: Measurements taken for the
purpose of determining employee exposure under this section are best
taken so that the average 8-hour exposure may be determined from a
single 8-hour sample or two (2) 4-hour samples. Air samples should be
taken in the employee's breathing zone (air that would most nearly
represent that inhaled by the employee).
2. Monitoring Techniques: The sampling and analysis under this
section may be performed by collecting the DBCP vapor on petroleum based
charcoal absorption tubes with subsequent chemical analyses. The method
of measurement chosen should determine the concentration of airborne
DBCP at the permissible exposure limit to an accuracy of plus or minus
25 percent. If charcoal tubes are used, a total volume of 10 liters
should be collected at a flow rate of 50 cc. per minute for each tube.
Analyze the resultant samples as you would samples of halogenated
solvent.
B. Since many of the duties relating to employee protection are
dependent on the results of monitoring and measuring procedures,
employers should assure that the evaluation of employee exposures is
performed by a competent industrial hygienist or other technically
qualified person.
v. Protective Clothing
Employees should be required to wear appropriate protective clothing
to prevent any possibility of skin contact with DBCP. Because DBCP is
absorbed through the skin, it is important to prevent skin contact with
both liquid and solid forms of DBCP. Protective clothing should include
impermeable coveralls or similar fullbody work clothing, gloves,
headcoverings, and workshoes or shoe coverings. Standard rubber and
neoprene gloves do not offer adequate protection and should not be
relied upon to keep DBCP off the skin. DBCP should never be allowed to
remain on the skin. Clothing and shoes should not be allowed to become
contaminated with the material, and if they do, they should be promptly
removed and not worn again until completely free of the material. Any
protective clothing which has developed leaks or is otherwise found to
be defective should be repaired or replaced. Employees should also be
required to wear splash-proof safety goggles where there is any
possibility of DBCP contacting the eyes.
vi. Housekeeping and Hygiene Facilities
1. The workplace must be kept clean, orderly and in a sanitary
condition;
2. Dry sweeping and the use of compressed air is unsafe for the
cleaning of floors and other surfaces where DBCP dust or liquids are
found. To minimize the contamination of air with dust, vacuuming with
either portable or permanent systems must be used. If a portable unit is
selected, the exhaust must be attached to the general workplace exhaust
ventilation system, or collected within
[[Page 318]]
the vacuum unit equipped with high efficiency filters or other
appropriate means of contamination removal and not used for other
purposes. Units used to collect DBCP must be labeled.
3. Adequate washing facilities with hot and cold water must be
provided, and maintained in a sanitary condition. Suitable cleansing
agents should also be provided to assure the effective removal of DBCP
from the skin.
4. Change or dressing rooms with individual clothes storage
facilities must be provided to prevent the contamination of street
clothes with DBCP. Because of the hazardous nature of DBCP, contaminated
protective clothing must be stored in closed containers for cleaning or
disposal.
vii. Miscellaneous Precautions
A. Store DBCP in tightly closed containers in a cool, well
ventilated area.
B. Use of supplied-air suits or other impervious clothing (such as
acid suits) may be necessary to prevent skin contact with DBCP.
Supplied-air suits should be selected, used, and maintained under the
supervision of persons knowlegeable in the limitations and potential
life-endangering characteristics of supplied-air suits.
C. The use of air-conditioned suits may be necessary in warmer
climates.
D. Advise employees of all areas and operations where exposure to
DBCP could occur.
viii. Common Operations
Common operations in which exposure to DBCP is likely to occur are:
during its production; and during its formulation into pesticides and
fumigants.
Appendix C toSec. 1910.1044--Medical Surveillance Guidelines For DBCP
i. Route of Entry
Inhalation; skin absorption
ii. Toxicology
Recent data collected on workers involved in the manufacture and
formulation of DBCP has shown that DBCP can cause sterility at very low
levels of exposure. This finding is supported by studies showing that
DBCP causes sterility in animals. Chronic exposure to DBCP resulted in
pronounced necrotic action on the parenchymatous organs (i.e., liver,
kidney, spleen) and on the testicles of rats at concentrations as low as
5 ppm. Rats that were chronically exposed to DBCP also showed changes in
the composition of the blood, showing low RBC, hemoglobin, and WBC, and
high reticulocyte levels as well as functional hepatic disturbance,
manifesting itself in a long prothrombin time. Reznik et al. noted a
single dose of 100 mg produced profound depression of the nervous system
of rats. Their condition gradually improved. Acute exposure also
resulted in the destruction of the sex gland activity of male rats as
well as causing changes in the estrous cycle in female rats. Animal
studies have also associated DBCP with an increased incidence of
carcinoma. Olson, et al. orally administered DBCP to rats and mice 5
times per week at experimentally predetermined maximally tolerated doses
and at half those doses. As early as ten weeks after initiation of
treatment, DBCP induced a high incidence of squamous cell carcinomas of
the stomach with metastases in both species. DBCP also induced mammary
adenocarcinomas in the female rats at both dose levels.
iii. Signs and Symptoms
A. Inhalation: Nausea, eye irritation, conjunctivitis, respiratory
irritation, pulmonary congestion or edema, CNS depression with apathy,
sluggishness, and ataxia.
B. Dermal: Erythema or inflammation and dermatitis on repeated
exposure.
iv. Special Tests
A. Semen analysis: The following information excerpted from the
document ``Evaluation of Testicular Function'', submitted by the
Corporate Medical Department of the Shell Oil Company (exhibit 39-3),
may be useful to physicians conducting the medical surveillance program;
In performing semen analyses certain minimal but specific criteria
should be met:
1. It is recommended that a minimum of three valid semen analyses be
obtained in order to make a determination of an individual's average
sperm count.
2. A period of sexual abstinence is necessary prior to the
collection of each masturbatory sample. It is recommended that
intercourse or masturbation be performed 48 hours before the actual
specimen collection. A period of 48 hours of abstinence would follow;
then the masturbatory sample would be collected.
3. Each semen specimen should be collected in a clean, widemouthed,
glass jar (not necessarily pre-sterilized) in a manner designated by the
examining physician. Any part of the seminal fluid exam should be
initialed only after liquifaction is complete, i.e., 30 to 45 minutes
after collection.
4. Semen volume should be measured to the nearest \1/10\ of a cubic
centimeter.
5. Sperm density should be determined using routine techniques
involving the use of a white cell pipette and a hemocytometer chamber.
The immobilizing fluid most effective and most easily obtained for this
process is distilled water.
6. Thin, dry smears of the semen should be made for a morphologic
classification of the sperm forms and should be stained with either
hematoxalin or the more difficult, yet more precise, Papanicolaou
technique. Also
[[Page 319]]
of importance to record is obvious sperm agglutination, pyospermia,
delayed liquifaction (greater than 30 minutes), and hyperviscosity. In
addition, pH, using nitrazine paper, should be determined.
7. A total morphology evaluation should include percentages of the
following:
a. Normal (oval) forms,
b. Tapered forms,
c. Amorphous forms (include large and small sperm shapes),
d. Duplicated (either heads or tails) forms, and
e. Immature forms.
8. Each sample should be evaluated for sperm viability (percent
viable sperm moving at the time of examination) as well as sperm
motility (subjective characterization of ``purposeful forward sperm
progression'' of the majority of those viable sperm analyzed) within two
hours after collection, ideally by the same or equally qualified
examiner.
B. Serum determinations: The following serum determinations should
be performed by radioimmuno-assay techniques using National Institutes
of Health (NIH) specific antigen or antigen preparations of equivalent
sensitivity:
1. Serum follicle stimulating hormone (FSH);
2. Serum luteinizing hormone (LH); and
3. Serum total estrogen (females only).
v. Treatment
Remove from exposure immediately, give oxygen or artificial
resuscitation if indicated. Contaminated clothing and shoes should be
removed immediately. Flush eyes and wash contaminated skin. If swallowed
and the person is conscious, induce vomiting. Recovery from mild
exposures is usually rapid and complete.
vi. Surveillance and Preventive Considerations
A. Other considerations. DBCP can cause both acute and chronic
effects. It is important that the physician become familiar with the
operating conditions in which exposure to DBCP occurs. Those with
respiratory disorders may not tolerate the wearing of negative pressure
respirators.
B. Surveillance and screening. Medical histories and laboratory
examinations are required for each employee subject to exposure to DBCP.
The employer should screen employees for history of certain medical
conditions (listed below) which might place the employee at increased
risk from exposure.
1. Liver disease. The primary site of biotransformation and
detoxification of DBCP is the liver. Liver dysfunctions likely to
inhibit the conjugation reactions will tend to promote the toxic actions
of DBCP. These precautions should be considered before exposing persons
with impaired liver function to DBCP.
2. Renal disease. Because DBCP has been associated with injury to
the kidney it is important that special consideration be given to those
with possible impairment of renal function.
3. Skin desease. DBCP can penetrate the skin and can cause erythema
on prolonged exposure. Persons with pre-existing skin disorders may be
more susceptible to the effects of DBCP.
4. Blood dyscrasias. DBCP has been shown to decrease the content of
erythrocytes, hemoglobin, and leukocytes in the blood, as well as
increase the prothrombin time. Persons with existing blood disorders may
be more susceptible to the effects of DBCP.
5. Reproductive disorders. Animal studies have associated DBCP with
various effects on the reproductive organs. Among these effects are
atrophy of the testicles and changes in the estrous cycle. Persons with
pre-existing reproductive disorders may be at increased risk to these
effects of DBCP.
References
1. Reznik, Ya. B. and Sprinchan, G. K.: Experimental Data on the
Gonadotoxic effect of Nemagon, Gig. Sanit., (6), 1975, pp. 101-102,
(translated from Russian).
2. Faydysh, E. V., Rakhmatullaev, N. N. and Varshavskii, V. A.: The
Cytotoxic Action of Nemagon in a Subacute Experiment, Med. Zh.
Uzbekistana, (No. 1), 1970, pp. 64-65, (translated from Russian).
3. Rakhmatullaev, N. N.: Hygienic Characteristics of the Nematocide
Nemagon in Relation to Water Pollution Control, Hyg. Sanit., 36(3),
1971, pp. 344-348, (translated from Russian).
4. Olson, W. A. et al.: Induction of Stomach Cancer in Rats and Mice
by Halogenated Aliphatic Fumigants, Journal of the National Cancer
Institute, (51), 1973, pp. 1993-1995.
5. Torkelson, T. R. et al.: Toxicologic Investigations of 1,2-
Dibromo-3-chloropropane, Toxicology and Applied Pharmacology, 3, 1961
pp. 545-559.
[43 FR 11527, Mar. 17, 1978, as amended at 45 FR 35283, May 23, 1980; 49
FR 18295, Apr. 30, 1984; 54 FR 24334, June 7, 1989; 58 FR 35310, June
30, 1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1291, Jan. 8, 1998; 70 FR
1142, Jan. 5, 2005; 71 FR 16772, Apr. 3, 2006; 71 FR 50189, Aug. 24,
2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR
17782, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013]
Sec. 1910.1045 Acrylonitrile.
(a) Scope and application. (1) This section applies to all
occupational exposures to acrylonitrile (AN), Chemical Abstracts Service
Registry No.
[[Page 320]]
000107131, except as provided in paragraphs (a)(2) and (a)(3) of this
section.
(2) This section does not apply to exposures which result solely
from the processing, use, and handling of the following materials:
(i) ABS resins, SAN resins, nitrile barrier resins, solid nitrile
elastomers, and acrylic and modacrylic fibers, when these listed
materials are in the form of finished polymers, and products fabricated
from such finished polymers;
(ii) Materials made from and/or containing AN for which objective
data is reasonably relied upon to demonstrate that the material is not
capable of releasing AN in airborne concentrations in excess of 1 ppm as
an eight (8)-hour time-weighted average, under the expected conditions
of processing, use, and handling which will cause the greatest possible
release; and
(iii) Solid materials made from and/or containing AN which will not
be heated above 170 [deg]F during handling, use, or processing.
(3) An employer relying upon exemption under paragraph (a)(2)(ii)
shall maintain records of the objective data supporting that exemption,
and of the basis of the employer's reliance on the data, as provided in
paragraph (q) of this section.
(b) Definitions. Acrylonitrile or AN means acrylonitrile monomer,
chemical formula CH2=CHCN.
Action level means a concentration of AN of 1 ppm as an eight (8)-
hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for
Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the
employer whose duties require the person to enter a regulated area, or
any person entering such an area as a designated representative of
employees for the purpose of exercising the opportunity to observe
monitoring procedures under paragraph (r) of this section.
Decontamination means treatment of materials and surfaces by water
washdown, ventilation, or other means, to assure that the materials will
not expose employees to airborne concentrations of AN above 1 means the
Director, National Institute for Occupational Safety and Health, U.S.
Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to,
equipment failure, rupture of containers, or failure of control
equipment, which results in an unexpected massive release of AN.
Liquid AN means AN monomer in liquid form, and liquid or semiliquid
polymer intermediates, including slurries, suspensions, emulsions, and
solutions, produced during the polymerization of AN.
OSHA Area Office means the Area Office of the Occupational Safety
and Health Administration having jurisdiction over the geographic area
where the affected workplace is located.
(c) Permissible exposure limits--(1) Inhalation. (i) Time weighted
average limit (TWA). The employer shall assure that no employee is
exposed to an airborne concentration of acrylonitrile in excess of two
(2) parts acrylonitrile per million parts of air (2 ppm) as an eight
(8)-hour time-weighted average.
(ii) Ceiling limit. The employer shall assure that no employee is
exposed to an airborne concentration of acrylonitrile in excess of ten
(10) ppm as averaged over any fifteen (15)-minute period during the work
day.
(2) Dermal and eye exposure. The employer shall assure that no
employee is exposed to skin contact or eye contact with liquid AN.
(d) [Reserved]
(e) Exposure monitoring--(1) General. (i) Determinations of airborne
exposure levels shall be made from air samples that are representative
of each employee's exposure to AN over an eight (8)-hour period.
(ii) For the purposes of this section, employee exposure is that
exposure which would occur if the employee were not using a respirator.
(2) Initial monitoring. Each employer who has a place of employment
in which AN is present shall monitor each such workplace and work
operation to accurately determine the airborne concentrations of AN to
which employees may be exposed.
(3) Frequency. (i) If the monitoring required by this section
reveals employee
[[Page 321]]
exposure to be below the action level, the employer may discontinue
monitoring for that employee.
(ii) If the monitoring required by this section reveals employee
exposure to be at or above the action level but at or below the
permissible exposure limits, the employer must repeat such monitoring
for each such employee at least every 6 months. The employer must
continue these measurements every 6 months until at least two
consecutive measurements taken at least seven (7) days a part, are below
the action level, and thereafter the employer may discontinue monitoring
for that employee.
(iii) If the monitoring required by this section reveals employee
exposure to be in excess of the permissible exposure limits, the
employer must repeat these determinations for each such employee at
least quarterly. The employer must continue these quarterly measurements
until at least two consecutive measurements, taken at least seven (7)
days apart, are at or below the permissible exposure limits, and
thereafter the employer must monitor at least every 6 months.
(4) Additional monitoring. Whenever there has been a production,
process, control, or personnel change which may result in new or
additional exposures to AN, or whenever the employer has any other
reason to suspect a change which may result in new or additional
exposures to AN, additional monitoring which complies with this
paragraph shall be conducted.
(5) Employee notification. (i) The employer must, within 15 working
days after the receipt of the results of any monitoring performed under
this section, notify each affected employee of these results either
individually in writing or by posting the results in an appropriate
location that is accessible to employees.
(ii) Whenever the results indicate that the representative employee
exposure exceeds the permissible exposure limits, the employer shall
include in the written notice a statement that the permissible exposure
limits were exceeded and a description of the corrective action being
taken to reduce exposure to or below the permissible exposure limits.
(6) Accuracy of measurement. The method of measurement of employee
exposures shall be accurate to a confidence level of 95 percent, to
within plus or minus 35 percent for concentrations of AN at or above the
permissible exposure limits, and plus or minus 50 percent for
concentrations of AN below the permissible exposure limits.
(f) Regulated areas. (1) The employer shall establish regulated
areas where AN concentrations are in excess of the permissible exposure
limits.
(2) Regulated areas shall be demarcated and segregated from the rest
of the workplace, in any manner that minimizes the number of persons who
will be exposed to AN.
(3) Access to regulated areas shall be limited to authorized persons
or to persons otherwise authorized by the act or regulations issued
pursuant thereto.
(4) The employer shall assure that food or beverages are not present
or consumed, tobacco products are not present or used, and cosmetics are
not applied in the regulated area.
(g) Methods of compliance--(1) Engineering and work practice
controls. (i) By November 2, 1980, the employer shall institute
engineering and work practice controls to reduce and maintain employee
exposures to AN, to or below the permissible exposure limits, except to
the extent that the employer establishes that such controls are not
feasible.
(ii) Wherever the engineering and work practice controls which can
be instituted are not sufficient to reduce employee exposures to or
below the permissible exposure limits, the employer shall nonetheless
use them to reduce exposures to the lowest levels achievable by these
controls, and shall supplement them by the use of respiratory protection
which complies with the requirements of paragraph (h) of this section.
(2) Compliance program. (i) The employer shall establish and
implement a written program to reduce employee exposures to or below the
permissible exposure limits solely by means of engineering and work
practice controls, as required by paragraph (g)(1) of this section.
[[Page 322]]
(ii) Written plans for these compliance programs shall include at
least the following:
(A) A description of each operation or process resulting in employee
exposure to AN above the permissible exposure limits;
(B) An outline of the nature of the engineering controls and work
practices to be applied to the operation or process in question;
(C) A report of the technology considered in meeting the permissible
exposure limits;
(D) A schedule for implementation of engineering and work practice
controls for the operation or process, which shall project completion no
later than November 2, 1980; and
(E) Other relevant information.
(iii) The employer shall complete the steps set forth in the
compliance program by the dates in the schedule.
(iv) Written plans shall be submitted upon request to the Assistant
Secretary and the Director, and shall be available at the worksite for
examination and copying by the Assistant Secretary, the Director, or any
affected employee or representative.
(v) The plans required by this paragraph must be revised and updated
at least annually to reflect the current status of the program.
(h) Respiratory protection--(1) General. For employees who use
respirators required by this section, the employer must provide each
employee an appropriate respirator that complies with the requirements
of this paragraph. Respirators must be used during:
(i) Periods necessary to install or implement feasible engineering
and work-practice controls.
(ii) Work operations, such as maintenance and repair activities or
reactor cleaning, for which the employer establishes that engineering
and work-practice controls are not feasible.
(iii) Work operations for which feasible engineering and work-
practice controls are not yet sufficient to reduce employee exposure to
or below the permissible exposure limits.
(iv) Emergencies.
(2) Respirator program. (i) The employer must implement a
respiratory protection program in accordance withSec. 1910.134(b)
through (d) (except (d)(1)(iii), (d)(3)(iii)(b)(1), and (2)), and (f)
through (m), which covers each employee required by this section to use
a respirator.
(ii) If air-purifying respirators (chemical-cartridge or chemical-
canister types) are used:
(A) The air-purifying canister or cartridge must be replaced prior
to the expiration of its service life or at the completion of each
shift, whichever occurs first.
(B) A label must be attached to the cartridge or canister to
indicate the date and time at which it is first installed on the
respirator.
(3) Respirator selection. Employers must:
(i) Select, and provide to employees, the appropriate respirators
specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134.
(ii) For escape, provide employees with any organic vapor respirator
or any self-contained breathing apparatus permitted for use under
paragraph (h)(3)(i) of this standard.
(i) Emergency situations--(1) Written plans. (i) A written plan for
emergency situations shall be developed for each workplace where liquid
AN is present. Appropriate portions of the plan shall be implemented in
the event of an emergency.
(ii) The plan shall specifically provide that employees engaged in
correcting emergency conditions shall be equipped as required in
paragraph (h) of this section until the emergency is abated.
(iii) Employees not engaged in correcting the emergency shall be
evacuated from the area and shall not be permitted to return until the
emergency is abated.
(2) Alerting employees. Where there is the possibility of employee
exposure to AN in excess of the ceiling limit, a general alarm shall be
installed and used to promptly alert employees of such occurrences.
(j) Protective clothing and equipment--(1) Provision and use. Where
eye or skin contact with liquid AN may occur, the employer shall provide
at no cost to the employee, and assure that employees wear, impermeable
protective clothing or other equipment to protect any area of the body
which may come
[[Page 323]]
in contact with liquid AN. The provision of Sec.Sec. 1910.132 and
1910.133 shall be complied with.
(2) Cleaning and replacement. (i) The employer shall clean, launder,
maintain, or replace protective clothing and equipment required by this
section as needed to maintain their effectiveness.
(ii) The employer shall assure that impermeable protective clothing
which contacts or is likely to have contacted liquid AN shall be
decontaminated before being removed by the employee.
(iii) The employer shall assure that an employee whose
nonimpermeable clothing becomes wetted with liquid AN shall immediately
remove that clothing and proceed to shower. The clothing shall be
decontaminated before it is removed from the regulated area.
(iv) The employer shall assure that no employee removes protective
clothing or equipment from the change room, except for those employees
authorized to do so for the purpose of laundering, maintenance, or
disposal.
(v) The employer shall inform any person who launders or cleans
protective clothing or equipment of the potentially harmful effects of
exposure to AN.
(k) Housekeeping. (1) All surfaces shall be maintained free of
visible accumulations of liquid AN.
(2) For operations involving liquid AN, the employer shall institute
a program for detecting leaks and spills of liquid AN, including regular
visual inspections.
(3) Where spills of liquid AN are detected, the employer shall
assure that surfaces contacted by the liquid AN are decontaminated.
Employees not engaged in decontamination activities shall leave the area
of the spill, and shall not be permitted in the area until
decontamination is completed.
(l) Waste disposal. AN waste, scrap, debris, bags, containers, or
equipment shall be decontaminated before being incorporated in the
general waste disposal system.
(m) Hygiene facilities and practices. (1) Where employees are
exposed to airborne concentrations of AN above the permissible exposure
limits, or where employees are required to wear protective clothing or
equipment pursuant to paragraph (j) of this section, the facilities
required by 29 CFR 1910.141, including clean change rooms and shower
facilities, shall be provided by the employer for the use of those
employees, and the employer shall assure that the employees use the
facilities provided.
(2) The employer shall assure that employees wearing protective
clothing or equipment for protection from skin contact with liquid AN
shall shower at the end of the work shift.
(3) The employer shall assure that, in the event of skin or eye
exposure to liquid AN, the affected employee shall shower immediately to
minimize the danger of skin absorption.
(4) The employer shall assure that employees working in the
regulated area wash their hands and faces prior to eating.
(n) Medical surveillance--(1) General. (i) The employer shall
institute a program of medical surveillance for each employee who is or
will be exposed to AN at or above the action level, without regard to
the use of respirators. The employer shall provide each such employee
with an opportunity for medical examinations and tests in accordance
with this paragraph.
(ii) The employer shall assure that all medical examinations and
procedures are performed by or under the supervision of a licensed
physician, and that they shall be provided without cost to the employee.
(2) Initial examinations. At the time of initial assignment, or upon
institution of the medical surveillance program, the employer shall
provide each affected employee an opportunity for a medical examination,
including at least the following elements:
(i) A work history and medical history with special attention to
skin, respiratory, and gastrointestinal systems, and those nonspecific
symptoms, such as headache, nausea, vomiting, dizziness, weakness, or
other central nervous system dysfunctions that may be associated with
acute or with chronic exposure to AN;
(ii) A complete physical examination giving particular attention to
the peripheral and central nervous system, gastrointestinal system,
respiratory system, skin, and thyroid;
[[Page 324]]
(iii) A 14- by 17-inch posteroanterior chest X-ray; and
(iv) Further tests of the intestinal tract, including fecal occult
blood screening, for all workers 40 years of age or older, and for any
other affected employees for whom, in the opinion of the physician, such
testing is appropriate.
(3) Periodic examinations. (i) The employer shall provide the
examinations specified in paragraph (n)(2) of this section at least
annually for all employees specified in paragraph (n)(1) of this
section.
(ii) If an employee has not had the examination specified in
paragraph (n)(2) of this section within 6 months preceding termination
of employment, the employer shall make such examination available to the
employee prior to such termination.
(4) Additional examinations. If the employee for any reason develops
signs or symptoms which may be associated with exposure to AN, the
employer shall provide an appropriate examination and emergency medical
treatment.
(5) Information provided to the physician. The employer shall
provide the following information to the examining physician:
(i) A copy of this standard and its appendixes;
(ii) A description of the affected employee's duties as they relate
to the employee's exposure;
(iii) The employee's representative exposure level;
(iv) The employee's anticipated or estimated exposure level (for
preplacement examinations or in cases of exposure due to an emergency);
(v) A description of any personal protective equipment used or to be
used; and
(vi) Information from previous medical examinations of the affected
employee, which is not otherwise available to the examining physician.
(6) Physician's written opinion. (i) The employer shall obtain a
written opinion from the examining physician which shall include:
(A) The results of the medical examination and test performed;
(B) The physician's opinion as to whether the employee has any
detected medical condition(s) which would place the employee at an
increased risk of material impairment of the employee's health from
exposure to AN;
(C) Any recommended limitations upon the employee's exposure to AN
or upon the use of protective clothing and equipment such as
respirators; and
(D) A statement that the employee has been informed by the physician
of the results of the medical examination and any medical conditions
which require further examination or treatment.
(ii) The employer shall instruct the physician not to reveal in the
written opinion specific findings or diagnoses unrelated to occupational
exposure to AN.
(iii) The employer shall provide a copy of the written opinion to
the affected employee.
(o) Employee information and training--(1) Training program. (i) The
employer shall train each employee exposed to AN above the action level,
each employee whose exposures are maintained below the action level by
engineering and work practice controls, and each employee subject to
potential skin or eye contact with liquid AN in accordance with the
requirements of this section. The employer shall institute a training
program and ensure employee participation in the program.
(ii) Training shall be provided at the time of initial assignment,
or upon institution of the training program, and at least annually
thereafter, and the employer shall assure that each employee is informed
of the following:
(A) The information contained in appendixes A and B;
(B) The quantity, location, manner of use, release, or storage of
AN, and the specific nature of operations which could result in exposure
to AN, as well as any necessary protective steps;
(C) The purpose, proper use, and limitations of respirators and
protective clothing;
(D) The purpose and a description of the medical surveillance
program required by paragraph (n) of this section;
(E) The emergency procedures developed, as required by paragraph (i)
of this section;
[[Page 325]]
(F) Engineering and work practice controls, their function, and the
employee's relationship to these controls; and
(G) A review of this standard.
(2) Access to training materials. (i) The employer shall make a copy
of this standard and its appendixes readily available to all affected
employees.
(ii) The employer shall provide, upon request, all materials
relating to the employee information and training program to the
Assistant Secretary and the Director.
(p) Communication of hazards--(1) Hazard communication--general. (i)
Chemical manufacturers, importers, distributors and employers shall
comply with all requirements of the Hazard Communication Standard (HCS)
(Sec. 1910.1200) for AN and AN-based materials not exempted under
paragraph (a)(2) of this section.
(ii) In classifying the hazards of AN and AN-based materials at
least the following hazards are to be addressed: Cancer; central nervous
system effects; liver effects; skin sensitization; skin, respiratory,
and eye irritation; acute toxicity effects; and flammability.
(iii) Employers shall include AN and AN-based materials in the
hazard communication program established to comply with the HCS (Sec.
1910.1200). Employers shall ensure that each employee has access to
labels on containers of AN and AN-based materials and to safety data
sheets, and is trained in accordance with the requirements of HCS and
paragraph (o) of this section.
(iv) The employer shall ensure that no statement appears on or near
any sign or label required by this paragraph (p) that contradicts or
detracts from the required sign or label.
(2) Signs. (i) The employer shall post signs to clearly indicate all
workplaces where AN concentrations exceed the permissible exposure
limits. The signs shall bear the following legend:
DANGER
ACRYLONITRILE (AN)
MAY CAUSE CANCER
RESPIRATORY PROTECTION MAY BE REQURED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
(ii) The employer shall ensure that signs required by this paragraph
(p)(2) are illuminated and cleaned as necessary so that the legend is
readily visible.
(iii) Prior to June 1, 2016, employers may use the following legend
in lieu of that specified in paragraph (p)(2)(i) of this section:
DANGER
ACRYLONITRILE (AN)
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS MAY BE REQUIRED
(3) Labels. (i) The employer shall ensure that precautionary labels
are in compliance with paragraph (p)(1)(i) of this section and are
affixed to all containers of liquid AN and AN-based materials not
exempted under paragraph (a)(2) of this section. The employer shall
ensure that the labels remain affixed when the materials are sold,
distributed, or otherwise leave the employer's workplace.
(ii) Prior to June 1, 2015, employers may include the following
information on precautionary labels required by this paragraph (p)(3) in
lieu of the labeling requirements in paragraph (p)(1) of this section:
DANGER
CONTAINS ACRYLONITRILE (AN)
CANCER HAZARD
(iii) The employer shall ensure that the precautionary labels
required by this paragraph (p)(3) are readily visible and legible.
(q) Recordkeeping--(1) Objective data for exempted operations. (i)
Where the processing, use, and handling of materials made from or
containing AN are exempted pursuant to paragraph (a)(2)(ii) of this
section, the employer shall establish and maintain an accurate record of
objective data reasonably relied upon in support of the exemption.
(ii) This record shall include at least the following information:
(A) The material qualifying for exemption;
(B) The source of the objective data;
(C) The testing protocol, results of testing, and/or analysis of the
material for the release of AN;
(D) A description of the operation exempted and how the data
supports the exemption; and
[[Page 326]]
(E) Other data relevant to the operations, materials, and processing
covered by the exemption.
(iii) The employer shall maintain this record for the duration of
the employer's reliance upon such objective data.
(2) Exposure monitoring. (i) The employer shall establish and
maintain an accurate record of all monitoring required by paragraph (e)
of this section.
(ii) This record shall include:
(A) The dates, number, duration, and results of each of the samples
taken, including a description of the sampling procedure used to
determine representative employee exposure;
(B) A description of the sampling and analytical methods used and
the data relied upon to establish that the methods used meet the
accuracy and precision requirements of paragraph (e)(6) of this section;
(C) Type of respiratory protective devices worn, if any; and
(D) Name, social security number, and job classification of the
employee monitored and of all other employees whose exposure the
measurement is intended to represent.
(iii) The employer shall maintain this record for at least forty
(40) years, or for the duration of employment plus twenty (20) years,
whichever is longer.
(3) Medical surveillance. (i) The employer shall establish and
maintain an accurate record for each employee subject to medical
surveillance as required by paragraph (n) of this section.
(ii) This record shall include:
(A) A copy of the physician's written opinions;
(B) Any employee medical complaints related to exposure to AN;
(C) A copy of the information provided to the physician as required
by paragraph (n)(5) of this section; and
(D) A copy of the employee's medical and work history.
(iii) The employer shall assure that this record be maintained for
at least forty (40) years, or for the duration of employment plus twenty
(20) years, whichever is longer.
(4) Availability. (i) The employer shall make all records required
to be maintained by this section available, upon request, to the
Assistant Secretary and the Director for examination and copying.
(ii) Records required by paragraphs (q)(1) through (q)(3) of this
section shall be provided upon request to employees, designated
representatives, and the Assistant Secretary in accordance with 29 CFR
1910.1020 (a) through (e) and (q) through (i). Records required by
paragraph (q)(1) shall be provided in the same manner as exposure
monitoring records.
(5) Transfer of records. (i) Whenever the employer ceases to do
business, the successor employer shall receive and retain all records
required to be maintained by this section for the prescribed period.
(ii) The employer shall also comply with any additional requirements
involving transfer of records set forth in 29 CFR 1910.1020(h).
(r) Observation of monitoring--(1) Employee observation. The
employer shall provide affected employees, or their designated
representatives, an opportunity to observe any monitoring of employee
exposure to AN conducted pursuant to paragraph (e) of this section.
(2) Observation procedures. (i) Whenever observation of the
monitoring of employee exposure to AN requires entry into an area where
the use of protective clothing or equipment is required, the employer
shall provide the observer with personal protective clothing and
equipment required to be worn by employees working in the area, assure
the use of such clothing and equipment, and require the observer to
comply with all other applicable safety and health procedures.
(ii) Without interfering with the monitoring, observers shall be
entitled:
(A) To receive an explanation of the measurement procedures;
(B) To observe all steps related to the measurement of airborne
concentrations of AN performed at the place of exposure; and
(C) To record the results obtained.
(s) [Reserved]
(t) Appendixes. The information contained in the appendixes is not
intended, by itself, to create any additional obligation not otherwise
imposed, or to detract from any obligation.
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Appendix A toSec. 1910.1045--Substance Safety Data Sheet for
Acrylonitrile
i. Substance Identification
A. Substance: Acrylonitrile (CH2 CHCN).
B. Synonyms: Propenenitrile; vinyl cyanide; cyanoethylene; AN; VCN;
acylon; carbacryl; fumigrian; ventox.
C. Acrylonitrile can be found as a liquid or vapor, and can also be
found in polymer resins, rubbers, plastics, polyols, and other polymers
having acrylonitrile as a raw or intermediate material.
D. AN is used in the manufacture of acrylic and modiacrylic fibers,
acrylic plastics and resins, speciality polymers, nitrile rubbers, and
other organic chemicals. It has also been used as a fumigant.
E. Appearance and odor: Colorless to pale yellow liquid with a
pungent odor which can only be detected at concentrations above the
permissible exposure level, in a range of 13-19 parts AN per million
parts of air (13-19 ppm).
F. Permissible exposure: Exposure may not exceed either:
1. Two parts AN per million parts of air (2 ppm) averaged over the
8-hour workday; or
2. Ten parts AN per million parts of air (10 ppm) averaged over any
15-minute period in the workday.
3. In addition, skin and eye contact with liquid AN is prohibited.
ii. Health Hazard Data
A. Acrylonitrile can affect your body if you inhale the vapor
(breathing), if it comes in contact with your eyes or skin, or if you
swallow it. It may enter your body through your skin.
B. Effects of overexposure: 1. Short-term exposure: Acrylonitrile
can cause eye irritation, nausea, vomiting, headache, sneezing,
weakness, and light-headedness. At high concentrations, the effects of
exposure may go on to loss of consciousness and death. When
acrylonitrile is held in contact with the skin after being absorbed into
shoe leather or clothing, it may produce blisters following several
hours of no apparent effect. Unless the shoes or clothing are removed
immediately and the area washed, blistering will occur. Usually there is
no pain or inflammation associated with blister formation.
2. Long-term exposure: Acrylonitrile has been shown to cause cancer
in laboratory animals and has been associated with higher incidences of
cancer in humans. Repeated or prolonged exposure of the skin to
acrylonitrile may produce irritation and dermatitis.
3. Reporting signs and symptoms: You should inform your employer if
you develop any signs or symptoms and suspect they are caused by
exposure to acrylonitrile.
iii. Emergency First Aid Procedures
A. Eye exposure: If acrylonitrile gets into your eyes, wash your
eyes immediately with large amounts of water, lifting the lower and
upper lids occasionally. Get medical attention immediately. Contact
lenses should not be worn when working with this chemical.
B. Skin exposure: If acrylonitrile gets on your skin, immediately
wash the contaminated skin with water. If acrylonitrile soaks through
your clothing, especially your shoes, remove the clothing immediately
and wash the skin with water. If symptoms occur after washing, get
medical attention immediately. Thoroughly wash the clothing before
reusing. Contaminated leather shoes or other leather articles should be
discarded.
C. Inhalation: If you or any other person breathes in large amounts
of acrylonitrile, move the exposed person to fresh air at once. If
breathing has stopped, perform artificial respiration. Keep the affected
person warm and at rest. Get medical attention as soon as possible.
D. Swallowing: When acrylonitrile has been swallowed, give the
person large quantities of water immediately. After the water has been
swallowed, try to get the person to vomit by having him touch the back
of his throat with his finger. Do not make an unconscious person vomit.
Get medical attention immediately.
E. Rescue: Move the affected person from the hazardous exposure. If
the exposed person has been overcome, notify someone else and put into
effect the established emergency procedures. Do not become a casualty
yourself. Understand your emergency rescue procedures and know the
location of the emergency equipment before the need arises.
F. Special first aid procedures: First aid kits containing an
adequate supply (at least two dozen) of amyl nitrite pearls, each
containing 0.3 ml, should be maintained at each site where acrylonitrile
is used. When a person is suspected of receiving an overexposure to
acrylonitrile, immediately remove that person from the contaminated area
using established rescue procedures. Contaminated clothing must be
removed and the acrylonitrile washed from the skin immediately.
Artificial respiration should be started at once if breathing has
stopped. If the person is unconscious, amyl nitrite may be used as an
antidote by a properly trained individual in accordance with established
emergency procedures. Medical aid should be obtained immediately.
iv. Respirators and Protective Clothing
A. Respirators. You may be required to wear a respirator for
nonroutine activities, in emergencies, while your employer is in the
process of reducing acrylonitrile exposures through engineering
controls, and in
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areas where engineering controls are not feasible. If respirators are
worn, they must have a label issued by the National Institute for
Occupational Safety and Health under the provisions of 42 CFR part 84
stating that the respirators have been approved for use with organic
vapors. For effective protection, respirators must fit your face and
head snugly. Respirators must not be loosened or removed in work
situations where their use is required.
Acrylonitrile does not have a detectable odor except at levels above
the permissible exposure limits. Do not depend on odor to warn you when
a respirator cartridge or canister is exhausted. Cartridges or canisters
must be changed daily or before the end-of-service-life, whichever comes
first. Reuse of these may allow acrylonitrille to gradually filter
through the cartridge and cause exposures which you cannot detect by
odor. If you can smell acrylonitrile while wearing a respirator, proceed
immediately to fresh air. If you experience difficulty breathing while
wearing a respirator, tell your employer.
B. Supplied-air suits: In some work situations, the wearing of
supplied-air suits may be necessary. Your employer must instruct you in
their proper use and operation.
C. Protective clothing: You must wear impervious clothing, gloves,
face shield, or other appropriate protective clothing to prevent skin
contact with liquid acrylonitrile. Where protective clothing is
required, your employer is required to provide clean garments to you as
necessary to assume that the clothing protects you adequately.
Replace or repair impervious clothing that has developed leaks.
Acrylonitrile should never be allowed to remain on the skin.
Clothing and shoes which are not impervious to acrylonitrile should not
be allowed to become contaminated with acrylonitrile, and if they do the
clothing and shoes should be promptly removed and decontaminated. The
clothing should be laundered or discarded after the AN is removed. Once
acrylonitrile penetrates shoes or other leather articles, they should
not be worn again.
D. Eye protection: You must wear splashproof safety goggles in areas
where liquid acrylonitrile may contact your eyes. In addition, contact
lenses should not be worn in areas where eye contact with acrylonitrile
can occur.
v. Precautions for Safe Use, Handling, and Storage
A. Acrylonitrile is a flammable liquid, and its vapors can easily
form explosive mixtures in air.
B. Acrylonitrile must be stored in tightly closed containers in a
cool, well-ventilated area, away from heat, sparks, flames, strong
oxidizers (especially bromine), strong bases, copper, copper alloys,
ammonia, and amines.
C. Sources of ignition such as smoking and open flames are
prohibited wherever acrylonitrile is handled, used, or stored in a
manner that could create a potential fire or explosion hazard.
D. You should use non-sparking tools when opening or closing metal
containers of acrylonitrile, and containers must be bonded and grounded
when pouring or transferring liquid acrylonitrile.
E. You must immediately remove any non-impervious clothing that
becomes wetted with acrylonitrile, and this clothing must not be reworn
until the acrylonitrile is removed from the clothing.
F. Impervious clothing wet with liquid acrylonitrile can be easily
ignited. This clothing must be washed down with water before you remove
it.
G. If your skin becomes wet with liquid acrylonitrile, you must
promptly and thoroughly wash or shower with soap or mild detergent to
remove any acrylonitrile from your skin.
H. You must not keep food, beverages, or smoking materials, nor are
you permitted to eat or smoke in regulated areas where acrylonitrile
concentrations are above the permissible exposure limits.
I. If you contact liquid acrylonitrile, you must wash your hands
thoroughly with soap or mild detergent and water before eating, smoking,
or using toilet facilities.
J. Fire extinguishers and quick drenching facilities must be readily
available, and you should know where they are and how to operate them.
K. Ask your supervisor where acrylonitrile is used in your work area
and for any additional plant safety and health rules.
vi. Access to Information
A. Each year, your employer is required to inform you of the
information contained in this Substance Safety Data Sheet for
acrylonitrile. In addition, you employer must instruct you in the proper
work practices for using acrylonitrile, emergency procedures, and the
correct use of protective equipment.
B. Your employer is required to determine whether you are being
exposed to acrylonitrile. You or your representative has the right to
observe employee measurements and to record the results obtained. Your
employer is required to inform you of your exposure. If your employer
determines that you are being overexposed, he or she is required to
inform you of the actions which are being taken to reduce your exposure
to within permissible exposure limits.
C. Your employer is required to keep records of your exposures and
medical examinations. These records must be kept by the employer for at
least forty (40) years or for the period of your employment plus twenty
(20) years, whichever is longer.
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D. Your employer is required to release your exposure and medical
records to you or your representative upon your request.
Appendix B toSec. 1910.1045--Substance Technical Guidelines for
Acrylonitrile
i. Physical and Chemical Data
A. Substance identification: 1. Synonyms: AN; VCN; vinyl cyanide;
propenenitrile; cyanoethylene; Acrylon; Carbacryl; Fumigrain; Ventox.
2. Formula: CH2=CHCN.
3. Molecular weight: 53.1.
B. Physical data: 1. Boiling point (760 mm Hg): 77.3 [deg]C (171
[deg]F);
2. Specific gravity (water=1): 0.81 (at 20 [deg]C or 68 [deg]F);
3. Vapor density (air=1 at boiling point of acrylonitrile): 1.83;
4. Melting point: -83 [deg]C (-117 [deg]F);
5. Vapor pressure (@20 [deg]F): 83 mm Hg;
6. Solubility in water, percent by weight @20 [deg]C (68 [deg]F):
7.35;
7. Evaporation rate (Butyl Acetate=1): 4.54; and
8. Appearance and odor: Colorless to pale yellow liquid with a
pungent odor at concentrations above the permissible exposure level. Any
detectable odor of acrylonitrile may indicate overexposure.
ii. Fire, Explosion, and Reactivity Hazard Data
A. Fire: 1. Flash point: -1 [deg]C (30 [deg]F) (closed cup).
2. Autoignition temperature: 481 [deg]C (898 [deg]F).
3. Flammable limits air, percent by volume: Lower: 3, Upper: 17.
4. Extinguishing media: Alcohol foam, carbon dioxide, and dry
chemical.
5. Special fire-fighting procedures: Do not use a solid stream of
water, since the stream will scatter and spread the fire. Use water to
cool containers exposed to a fire.
6. Unusual fire and explosion hazards: Acrylonitrile is a flammable
liquid. Its vapors can easily form explosive mixtures with air. All
ignition sources must be controlled where acrylonitrile is handled,
used, or stored in a manner that could create a potential fire or
explosion hazard. Acrylonitrile vapors are heavier than air and may
travel along the ground and be ignited by open flames or sparks at
locations remote from the site at which acrylonitrile is being handled.
7. For purposes of compliance with the requirements of 29 CFR
1910.106, acrylonitrile is classified as a class IB flammable liquid.
For example, 7,500 ppm, approximately one-fourth of the lower flammable
limit, would be considered to pose a potential fire and explosion
hazard.
8. For purposes of compliance with 29 CFR 1910.157, acrylonitrile is
classified as a Class B fire hazard.
9. For purpose of compliance with 29 CFR 1919.309, locations
classified as hazardous due to the presence of acrylonitrile shall be
Class I, Group D.
B. Reactivity:
1. Conditions contributing to instability: Acrylonitrile will
polymerize when hot, and the additional heat liberated by the
polymerization may cause containers to explode. Pure AN may self-
polymerize, with a rapid build-up of pressure, resulting in an explosion
hazard. Inhibitors are added to the commercial product to prevent self-
polymerization.
2. Incompatibilities: Contact with strong oxidizers (especially
bromine) and strong bases may cause fires and explosions. Contact with
copper, copper alloys, ammonia, and amines may start serious
decomposition.
3. Hazardous decompostion products: Toxic gases and vapors (such as
hydrogen cyanide, oxides of nitrogen, and carbon monoxide) may be
released in a fire involving acrylonitrile and certain polymers made
from acrylonitrile.
4. Special precautions: Liquid acrylonitrile will attack some forms
of plastics, rubbers, and coatings.
iii. Spill, Leak, and Disposal Procedures
A. If acrylonitrile is spilled or leaked, the following steps should
be taken:
1. Remove all ignition sources.
2. The area should be evacuated at once and re-entered only after
the area has been thoroughly ventilated and washed down with water.
3. If liquid acrylonitrile or polymer intermediate, collect for
reclamation or absorb in paper, vermiculite, dry sand, earth, or similar
material, or wash down with water into process sewer system.
B. Persons not wearing protective equipment should be restricted
from areas of spills or leaks until clean-up has been completed.
C. Waste disposal methods: Waste material shall be disposed of in a
manner that is not hazardous to employees or to the general population.
Spills of acrylonitrile and flushing of such spills shall be channeled
for appropriate treatment or collection for disposal. They shall not be
channeled directly into the sanitary sewer system. In selecting the
method of waste disposal, applicable local, State, and Federal
regulations should be consulted.
iv. Monitoring and Measurement Procedures
A. Exposure above the Permissible Exposure Limit:
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1. Eight-hour exposure evaluation: Measurements taken for the
purpose of determining employee exposure under this section are best
taken so that the average 8-hour exposure may be determined from a
single 8-hour sample or two (2) 4-hour samples. Air samples should be
taken in the employee's breathing zone (air that would most nearly
represent that inhaled by the employee.)
2. Ceiling evaluation: Measurements taken for the purpose of
determining employee exposure under this section must be taken during
periods of maximum expected airborne concentrations of acrylonitrile in
the employee's breathing zone. A minimum of three (3) measurements
should be taken on one work shift. The average of all measurements taken
is an estimate of the employee's ceiling exposure.
3. Monitoring techniques: The sampling and analysis under this
section may be performed by collecting the acrylonitrile vapor on
charcoal adsorption tubes or other composition adsorption tubes, with
subsequent chemical analysis. Sampling and analysis may also be
performed by instruments such as real-time continuous monitoring
systems, portable direct-reading instruments, or passive dosimeters.
Analysis of resultant samples should be by gas chromatograph.
Appendix D lists methods of sampling and analysis which have been
tested by NIOSH and OSHA for use with acrylonitrile. NIOSH and OSHA have
validated modifications of NIOSH Method S-156 (See appendix D) under
laboratory conditions for concentrations below 1 ppm. The employer has
the obligation of selecting a monitoring method which meets the accuracy
and precision requirements of the standard under his unique field
conditions. The standard requires that methods of monitoring must be
accurate, to a 95-percent confidence level, to 35-
percent for concentrations of AN at or above 2 ppm, and to 50-percent for concentrations below 2 ppm. In addition
to the methods described in appendix D, there are numerous other methods
available for monitoring for AN in the workplace. Details on these other
methods have been submitted by various companies to the rulemaking
record, and are available at the OSHA Docket Office.
B. Since many of the duties relating to employee exposure are
dependent on the results of monitoring and measuring procedures,
employers shall assure that the evaluation of employee exposures is
performed by a competent industrial hygienist or other technically
qualified person.
v. Protective Clothing
Employees shall be provided with and required to wear appropriate
protective clothing to prevent any possibility of skin contact with
liquid AN. Because acrylonitrile is absorbed through the skin, it is
important to prevent skin contact with liquid AN. Protective clothing
shall include impermeable coveralls or similar full-body work clothing,
gloves, head-coverings, as appropriate to protect areas of the body
which may come in contact with liquid AN.
Employers should ascertain that the protective garmets are
impermeable to acrylonitrile. Non-impermeable clothing and shoes should
not be allowed to become contaminated with liquid AN. If permeable
clothing does become contaminated, it should be promptly removed, placed
in a regulated area for removal of the AN, and not worn again until the
AN is removed. If leather footwear or other leather garments become wet
from acrylonitrile, they should be replaced and not worn again, due to
the ability of leather to absorb acrylonitrile and hold it against the
skin. Since there is no pain associated with the blistering which may
result from skin contact with liquid AN, it is essential that the
employee be informed of this hazard so that he or she can be protected.
Any protective clothing which has developed leaks or is otherwise
found to be defective shall be repaired or replaced. Clean protective
clothing shall be provided to the employee as necessary to assure its
protectiveness. Whenever impervious clothing becomes wet with liquid AN,
it shall be washed down with water before being removed by the employee.
Employees are also required to wear splash-proof safety goggles where
there is any possibility of acrylonitrile contacting the eyes.
vi. Housekeeping and Hygiene Facilities
For purposes of complying with 29 CFR 1910.141, the following items
should be emphasized:
A. The workplace should be kept clean, orderly, and in a sanitary
condition. The employer is required to institute a leak and spill
detection program for operations involving liquid AN in order to detect
sources of fugitive AN emissions.
B. Dry sweeping and the use of compressed air is unsafe for the
cleaning of floors and other surfaces where liquid AN may be found.
C. Adequate washing facilities with hot and cold water are to be
provided, and maintained in a sanitary condition. Suitable cleansing
agents are also to be provided to assure the effective removal of
acrylonitrile from the skin.
D. Change or dressing rooms with individual clothes storage
facilities must be provided to prevent the contamination of street
clothes with acrylonitrile. Because of the hazardous nature of
acrylonitrile, contaminated protective clothing should be placed in a
regulated area designated by the employer for removal of the AN before
the clothing is laundered or disposed of.
[[Page 331]]
vii. Miscellaneous Precautions
A. Store acrylonitrile in tightly-closed containers in a cool, well-
ventilated area and take necessary precautions to avoid any explosion
hazard.
B. High exposures to acrylonitrile can occur when transferring the
liquid from one container to another.
C. Non-sparking tools must be used to open and close metal
acrylonitrile containers. These containers must be effectively grounded
and bonded prior to pouring.
D. Never store uninhibited acrylonitrile.
E. Acrylonitrile vapors are not inhibited. They may form polymers
and clog vents of storage tanks.
F. Use of supplied-air suits or other impervious coverings may be
necessary to prevent skin contact with and provide respiratory
protection from acrylonitrile where the concentration of acrylonitrile
is unknown or is above the ceiling limit. Supplied-air suits should be
selected, used, and maintained under the immediate supervision of
persons knowledgeable in the limitations and potential life-endangering
characteristics of supplied-air suits.
G. Employers shall advise employees of all areas and operations
where exposure to acrylonitrile could occur.
viii. Common Operations
Common operations in which exposure to acrylonitrile is likely to
occur include the following: Manufacture of the acrylonitrile monomer;
synthesis of acrylic fibers, ABS, SAN, and nitrile barrier plastics and
resins, nitrile rubber, surface coatings, specialty chemicals, use as a
chemical intermediate, use as a fumigant and in the cyanoethylation of
cotton.
Appendix C toSec. 1910.1045--Medical Surveillance Guidelines for
Acrylonitrile
i. route of entry
Inhalation; skin absorption; ingestion.
ii. toxicology
Acrylonitrile vapor is an asphyxiant due to inhibitory action on
metabolic enzyme systems. Animals exposed to 75 or 100 ppm for 7 hours
have shown signs of anoxia; in some animals which died at the higher
level, cyanomethemoglobin was found in the blood. Two human fatalities
from accidental poisioning have been reported; one was caused by
inhalation of an unknown concentration of the vapor, and the other was
thought to be caused by skin absorption or inhalation. Most cases of
intoxication from industrial exposure have been mild, with rapid onset
of eye irritation, headache, sneezing, and nausea. Weakness,
lightheadedness, and vomiting may also occur. Exposure to high
concentrations may produce profound weakness, asphyxia, and death. The
vapor is a severe eye irritant. Prolonged skin contract with the liquid
may result in absorption with systemic effects, and in the formation of
large blisters after a latent period of several hours. Although there is
usually little or no pain or inflammation, the affected skin resembles a
second-degree thermal burn. Solutions spilled on exposed skin, or on
areas covered only by a light layer of clothing, evaporate rapidly,
leaving no irritation, or, at the most, mild transient redness. Repeated
spills on exposed skin may result in dermatitis due to solvent effects.
Results after 1 year of a planned 2-year animal study on the effects
of exposure to acrylonitrile have indicated that rats ingesting as
little as 35 ppm in their drinking water develop tumors of the central
nervous system. The interim results of this study have been supported by
a similar study being conducted by the same laboratory, involving
exposure of rats by inhalation of acrylonitrile vapor, which has shown
similar types of tumors in animals exposed to 80 ppm.
In addition, the preliminary results of an epidemiological study
being performed by duPont on a cohort of workers in their Camden, S.C.
acrylic fiber plant indicate a statistically significant increase in the
incidence of colon and lung cancers among employees exposed to
acrylonitrile.
iii. signs and symptoms of acute overexposure
Asphyxia and death can occur from exposure to high concentrations of
acrylonitrile. Symptoms of overexposure include eye irritation,
headache, sneezing, nausea and vomiting, weakness, and light-headedness.
Prolonged skin contact can cause blisters on the skin with appearance of
a second-degree burn, but with little or no pain. Repeated skin contact
may produce scaling dermatits.
iv. treatment of acute overexposure
Remove employee from exposure. Immediately flush eyes with water and
wash skin with soap or mild detergent and water. If AN has been
swallowed, and person is conscious, induce vomiting. Give artificial
resuscitation if indicated. More severe cases, such as those associated
with loss of consciousness, may be treated by the intravenous
administration of sodium nitrite, followed by sodium thiosulfate,
although this is not as effective for acrylonitrile poisoning as for
inorganic cyanide poisoning.
v. surveillance and preventive considerations
A. As noted above, exposure to acrylonitrile has been linked to
increased incidence of cancers of the colon and lung in employees of the
duPont acrylic fiber plant in
[[Page 332]]
Camden, S.C. In addition, the animal testing of acrylonitrile has
resulted in the development of cancers of the central nervous system in
rats exposed by either inhalation or ingestion. The physician should be
aware of the findings of these studies in evaluating the health of
employees exposed to acrylonitrile.
Most reported acute effects of occupational exposure to
acrylonitrile are due to its ability to cause tissue anoxia and
asphyxia. The effects are similar to those caused by hydrogen cyanide.
Liquid acrylonitrile can be absorbed through the skin upon prolonged
contact. The liquid readily penetrates leather, and will produce burns
of the feet if footwear contaminated with acrylonitrile is not removed.
It is important for the physician to become familiar with the
operating conditions in which exposure to acrylonitrile may occur. Those
employees with skin diseases may not tolerate the wearing of whatever
protective clothing may be necessary to protect them from exposure. In
addition, those with chronic respiratory disease may not tolerate the
wearing of negative-pressure respirators.
B. Surveillance and screening. Medical histories and laboratory
examinations are required for each employee subject to exposure to
acrylonitrile above the action level. The employer must screen employees
for history of certain medical conditions which might place the employee
at increased risk from exposure.
1. Central nervous system dysfunction. Acute effects of exposure to
acrylonitrile generally involve the central nervous system. Symptoms of
acrylonitrile exposure include headache, nausea, dizziness, and general
weakness. The animal studies cited above suggest possible carcinogenic
effects of acrylonitrile on the central nervous system, since rats
exposed by either inhalation or ingestion have developed similar CNS
tumors.
2. Respiratory disease. The du Pont data indicate an increased risk
of lung cancer among employees exposed to acrylonitrile.
3. Gastrointestinal disease. The du Pont data indicate an increased
risk of cancer of the colon among employees exposed to acrylonitrile. In
addition, the animal studies show possible tumor production in the
stomachs of the rats in the ingestion study.
4. Skin disease. Acrylonitrile can cause skin burns when prolonged
skin contact with the liquid occurs. In addition, repeated skin contact
with the liquid can cause dermatitis.
5. General. The purpose of the medical procedures outlined in the
standard is to establish a baseline for future health monitoring.
Persons unusually susceptible to the effects of anoxia or those with
anemia would be expected to be at increased risk. In addition to
emphasis on the CNS, respiratory and gastro-intestinal systems, the
cardiovascular system, liver, and kidney function should also be
stressed.
Appendix D toSec. 1910.1045--Sampling and Analytical Methods for
Acrylonitrile
There are many methods available for monitoring employee exposures
to acrylonitrile. Most of these involve the use of charcoal tubes and
sampling pumps, with analysis by gas chromatograph. The essential
differences between the charcoal tube methods include, among others, the
use of different desorbing solvents, the use of different lots of
charcoal, and the use of different equipment for analysis of the
samples.
Besides charcoal, considerable work has been performed on methods
using porous polymer sampling tubes and passive dosimeters. In addition,
there are several portable gas analyzers and monitoring units available
on the open market.
This appendix contains details for the methods which have been
tested at OSHA Analytical Laboratory in Salt Lake City, and NIOSH in
Cincinnati. Each is a variation on NIOSH Method S-156, which is also
included for reference. This does not indicate that these methods are
the only ones which will be satisfactory. There also may be workplace
situations in which these methods are not adequate, due to such factors
as high humidity. Copies of the other methods available to OSHA are
available in the rulemaking record, and may be obtained from the OSHA
Docket Office. These include, the Union Carbide, Monsanto, Dow Chemical
and Dow Badische methods, as well as NISOH Method P & CAM 127.
Employers who note problems with sample breakthrough should try
larger charcoal tubes. Tubes of larger capacity are available, and are
often used for sampling vinyl chloride. In addition, lower flow rates
and shorter sampling times should be beneficial in minimizing
breakthrough problems.
Whatever method the employer chooses, he must assure himself of the
method's accuracy and precision under the unique conditions present in
his workplace.
NIOSH Method S-156 (Unmodified)
Analyte: Acrylonitrile.
Matrix: Air.
Procedure: Absorption on charcoal, desorption with methanol, GC.
1. Principle of the method (Reference 11.1).
1.1 A known volume of air is drawn through a charcoal tube to trap
the organic vapors present.
1.2 The charcoal in the tube is transferred to a small, stoppered
sample container, and the analyte is desorbed with methanol.
1.3 An aliquot of the desorbed sample is injected into a gas
chromatograph.
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1.4 The area of the resulting peak is determined and compared with
areas obtained for standards.
2. Range and sensitivity.
2.1 This method was validated over the range of 17.5-70.0 mg/cu m at
an atmospheric temperature and pressure of 22 [deg]C and 760 MM Hg,
using a 20-liter sample. Under the conditions of sample size (20-liters)
the probable useful range of this method is 4.5-135 mg-cu m. The method
is capable of measuring much smaller amounts if the desorption
efficiency is adequate. Desorption efficiency must be determined over
the range used.
2.2 The upper limit of the range of the method is dependent on the
adsorptive capacity of the charcoal tube. This capacity varies with the
concentrations of acrylonitrile and other substances in the air. The
first section of the charcoal tube was found to hold at least 3.97 mg of
acrylonitrile when a test atmosphere containing 92.0 mg/cu m of
acrylonitrile in air was sampled 0.18 liter per minute for 240 minutes;
at that time the concentration of acrylonitrile in the effluent was less
than 5 percent of that in the influent. (The charcoal tube consists of
two sections of activated charcoal separated by a section of urethane
foam. See section 6.2.) If a particular atmosphere is suspected of
containing a large amount of contaminant, a smaller sampling volume
should be taken.
3. Interference.
3.1 When the amount of water in the air is so great that
condensation actually occurs in the tube, organic vapors will not be
trapped efficiently. Preliminary experiments using toluene indicate that
high humidity severely decreases the breakthrough volume.
3.2 When interfering compounds are known or suspected to be present
in the air, such information, including their suspected identities,
should be transmitted with the sample.
3.3 It must be emphasized that any compound which has the same
retention time as the analyte at the operating conditions described in
this method is an interference. Retention time data on a single column
cannot be considered proof of chemical identity.
3.4 If the possibility of interference exists, separation conditions
(column packing, temperature, etc.) must be changed to circumvent the
problem.
4. Precision and accuracy.
4.1 The Coefficient of Variation (CVT) for the total
analytical and sampling method in the range of 17.5-70.0 mg/cu m was
0.073. This value corresponds to a 3.3 mg/cu m standard deviation at the
(previous) OSHA standard level (20 ppm). Statistical information and
details of the validation and experimental test procedures can be found
in Reference 11.2.
4.2 On the average the concentrations obtained at the 20 ppm level
using the overall sampling and analytical method were 6.0 percent lower
than the ``true'' concentrations for a limited number of laboratory
experiments. Any difference between the ``found'' and ``true''
concentrations may not represent a bias in the sampling and analytical
method, but rather a random variation from the experimentally determined
``true'' concentration. Therefore, no recovery correction should be
applied to the final result in section 10.5.
5. Advantages and disadvantages of the method.
5.1 The sampling device is small, portable, and involves no liquids.
Interferences are minimal, and most of those which do occur can be
eliminated by altering chromatographic conditions. The tubes are
analyzed by means of a quick, instrumental method.
The method can also be used for the simultaneous analysis of two or
more substances suspected to be present in the same sample by simply
changing gas chromatographic conditions.
5.2 One disadvantage of the method is that the amount of sample
which can be taken is limited by the number of milligrams that the tube
will hold before overloading. When the sample value obtained for the
backup section of the charcoal tube exceeds 25 percent of that found on
the front section, the possibility of sample loss exists.
5.3 Furthermore, the precision of the method is limited by the
reproducibility of the pressure drop across the tubes. This drop will
affect the flow rate and cause the volume to be imprecise, because the
pump is usually calibrated for one tube only.
6. Apparatus.
6.1 A calibrated personal sampling pump whose flow can be determined
within 5 percent at the recommended flow rate.
(Reference 11.3).
6.2 Charcoal tubes: Glass tubes with both ends flame sealed, 7 cm
long with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40
mesh activated charcoal separated by a 2-mm portion of urethane foam.
The activated charcoals prepared from coconut shells and is fired at 600
[deg]C prior to packing. The adsorbing section contains 100 mg of
charcoal, the backup section 50 mg. A 3-mm portion of urethane foam is
placed between the outlet end of the tube and the backup section. A plug
of silicated glass wool is placed in front of the adsorbing section. The
pressure drop across the tube must be less than 1 inch of mercury at a
flow rate of 1 liter per minute.
6.3 Gas chromatograph equipped with a flame ionization detector.
6.4 Column (4-ftx\1/4\-in stainless steel) packed with 50/80 mesh
Poropak, type Q.
6.5 An electronic integrator or some other suitable method for
measuring peak areas.
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6.6 Two-milliliter sample containers with glass stoppers or Teflon-
lined caps. If an automatic sample injector is used, the associated
vials may be used.
6.7 Microliter syringes: 10-microliter and other convenient sizes
for making standards.
6.8 Pipets: 1.0-ml delivery pipets.
6.9 Volumetric flask: 10-ml or convenient sizes for making standard
solutions.
7. Reagents.
7.1 Chromatographic quality methanol.
7.2 Acrylonitrile, reagent grade.
7.3 Hexane, reagent grade.
7.4 Purified nitrogen.
7.5 Prepurified hydrogen.
7.6 Filtered compressed air.
8. Procedure.
8.1 Cleaning of equipment. All glassware used for the laboratory
analysis should be detergent washed and thoroughly rinsed with tap water
and distilled water.
8.2 Calibration of personal pumps. Each personal pump must be
calibrated with a representative charcoal tube in the line. This will
minimize errors associated with uncertainties in the sample volume
collected.
8.3 Collection and shipping of samples.
8.3.1 Immediately before sampling, break the ends of the tube to
provide an opening at least one-half the internal diameter of the tube
(2 mm).
8.3.2 The smaller section of charcoal is used as a backup and should
be positioned nearest the sampling pump.
8.3.3 The charcoal tube should be placed in a vertical direction
during sampling to minimize channeling through the charcoal.
8.3.4 Air being sampled should not be passed through any hose or
tubing before entering the charcoal tube.
8.3.5 A maximum sample size of 20 liters is recommended. Sample at a
flow of 0.20 liter per minute or less. The flow rate should be known
with an accuracy of at least 5 percent.
8.3.6 The temperature and pressure of the atmosphere being sampled
should be recorded. If pressure reading is not available, record the
elevation.
8.3.7 The charcoal tubes should be capped with the supplied plastic
caps immediately after sampling. Under no circumstances should rubber
caps be used.
8.3.8 With each batch of 10 samples submit one tube from the same
lot of tubes which was used for sample collection and which is subjected
to exactly the same handling as the samples except that no air is drawn
through it. Label this as a blank.
8.3.9 Capped tubes should be packed tightly and padded before they
are shipped to minimize tube breakage during shipping.
8.3.10 A sample of the bulk material should be submitted to the
laboratory in a glass container with a Teflon-lined cap. This sample
should not be transported in the same container as the charcoal tubes.
8.4 Analysis of samples.
8.4.1 Preparation of samples. In preparation for analysis, each
charcoal tube is scored with a file in front of the first section of
charcoal and broken open. The glass wool is removed and discarded. The
charcoal in the first (larger) section is transferred to a 2-ml
stoppered sample container. The separating section of foam is removed
and discarded; the second section is transferred to another stoppered
container. These two sections are analyzed separately.
8.4.2 Desorption of samples. Prior to analysis, 1.0 ml of methanol
is pipetted into each sample container. Desorption should be done for 30
minutes. Tests indicate that this is adequate if the sample is agitated
occasionally during this period. If an automatic sample injector is
used, the sample vials should be capped as soon as the solvent is added
to minimize volatilization.
8.4.3 GC conditions. The typical operating conditions for the gas
chromatograph are:
1. 50 ml/min (60 psig) nitrogen carrier gas flow.
2. 65 ml/min (24 psig) hydrogen gas flow to detector.
3. 500 ml/min (50 psig) air flow to detector.
4. 235 [deg]C injector temperature.
5. 255 [deg]C manifold temperature (detector).
6. 155 [deg]C column temperature.
8.4.4 Injection. The first step in the analysis is the injection of
the sample into the gas chromatograph. To eliminate difficulties arising
from blowback or distillation within the syringe needle, one should
employ the solvent flush injection technique. The 10-microliter syringe
is first flushed with solvent several times to wet the barrel and
plunger. Three microliters of solvent are drawn into the syringe to
increase the accuracy and reproducibility of the injected sample volume.
The needle is removed from the solvent, and the plunger is pulled back
about 0.2 microliter to separate the solvent flush from the sample with
a pocket of air to be used as a marker. The needle is then immersed in
the sample, and a 5-microliter aliquot is withdrawn, taking into
consideration the volume of the needle, since the sample in the needle
will be completely injected. After the needle is removed from the sample
and prior to injection, the plunger is pulled back 1.2 microliters to
minimize evaporation of the sample from the tip of the needle. Observe
that the sample occupies 4.9-5.0 microliters in the barrel of the
syringe. Duplicate injections of each sample and standard should be
made. No more than a 3 percent difference in area is to be expected. An
automatic sample injector can be used if it is shown to give
reproducibility at least as good as the solvent flush method.
8.4.5 Measurement of area. The area of the sample peak is measured
by an electronic integrator or some other suitable form of area
measurement, and preliminary results are
[[Page 335]]
read from a standard curve prepared as discussed below.
8.5 Determination of desorption efficiency.
8.5.1 Importance of determination. The desorption efficiency of a
particular compound can vary from one laboratory to another and also
from one batch of charcoal to another. Thus, it is necessary to
determine at least once the percentage of the specific compound that is
removed in the desorption process, provided the same batch of charcoal
is used.
8.5.2 Procedure for determining desorption efficiency. Activated
charcoal equivalent to the amount in the first section of the sampling
tube (100 mg) is measured into a 2.5 in, 4-mm I.D. glass tube, flame
sealed at one end. This charcoal must be from the same batch as that
used in obtaining the samples and can be obtained from unused charcoal
tubes. The open end is capped with Parafilm. A known amount of hexane
solution of acrylonitrile containing 0.239 g/ml is injected directly
into the activated charcoal with a microliter syringe, and tube is
capped with more Parafilm. When using an automatic sample injector, the
sample injector vials, capped with Teflon-faced septa, may be used in
place of the glass tube.
The amount injected is equivalent to that present in a 20-liter air
sample at the selected level.
Six tubes at each of three levels (0.5X, 1X, and 2X of the standard)
are prepared in this manner and allowed to stand for at least overnight
to assure complete adsorption of the analyte onto the charcoal. These
tubes are referred to as the sample. A parallel blank tube should be
treated in the same manner except that no sample is added to it. The
sample and blank tubes are desorbed and analyzed in exactly the same
manner as the sampling tube described in section 8.4.
Two or three standards are prepared by injecting the same volume of
compound into 1.0 ml of methanol with the same syringe used in the
preparation of the samples. These are analyzed with the samples.
The desorption efficiency (D.E.) equals the average weight in mg
recovered from the tube divided by the weight in mg added to the tube,
or
[GRAPHIC] [TIFF OMITTED] TC15NO91.035
The desorption efficiency is dependent on the amount of analyte
collected on the charcoal. Plot the desorption efficiency versus weight
of analyte found. This curve is used in section 10.4 to correct for
adsorption losses.
9. Calibration and standards.
It is convenient to express concentration of standards in terms of
mg/1.0 ml methanol, because samples are desorbed in this amount of
methanol. The density of the analyte is used to convert mg into
microliters for easy measurement with a microliter syringe. A series of
standards, varying in concentration over the range of interest, is
prepared and analyzed under the same GC conditions and during the same
time period as the unknown samples. Curves are established by plotting
concentration in mg/1.0 ml versus peak area.
Note: Since no internal standard is used in the method, standard
solutions must be analyzed at the same time that the sample analysis is
done. This will minimize the effect of known day-to-day variations and
variations during the same day of the FID response.
10. Calculations.
10.1 Read the weight, in mg, corresponding to each peak area from
the standard curve. No volume corrections are needed, because the
standard curve is based on mg/1.0 ml methanol and the volume of sample
injected is identical to the volume of the standards injected.
10.2 Corrections for the bank must be made for each sample.
mg = mg sample-mg blank
Where:
mg sample = mg found in front section of sample tube.
mg sample = mg found in front section of blank tube.
A similar procedure is followed for the backup sections.
10.3 Add the weights found in the front and backup sections to get
the total weight in the sample.
10.4 Read the desorption efficiency from the curve (see sec. 8.5.2)
for the amount found in the front section. Divide the total weight by
this desorption efficiency to obtain the corrected mg/sample.
[GRAPHIC] [TIFF OMITTED] TC15NO91.036
10.5 The concentration of the analyte in the air sampled can be
expressed in mg/cu m.
[GRAPHIC] [TIFF OMITTED] TC15NO91.037
[[Page 336]]
10.6 Another method of expressing concentration is ppm.
ppm =m mg/cu x 24.45/M.W. x 760/Px T. + 273/298
Where:
P = Pressure (mm Hg) of air sampled.
T = Temperature ([deg]C) of air sampled.
24.45 = Molar volume (liter/mole) at 25 [deg]C and 760 mm Hg.
M.W. = Molecular weight (g/mole) of analyte.
760 = Standard pressure (mm Hg).
298 = Standard temperature ([deg]K).
11. References.
11.1 White, L. D. et al., ``A Convenient Optimized Method for the
Analysis of Selected Solvent Vapors in the Industrial Atmosphere,''
Amer. Ind. Hyg. Assoc. J., 31:225 (1970).
11.2 Documentation of NIOSH Validation Tests, NIOSH Contract No.
CDC-99-74-45.
11.3 Final Report, NIOSH Contract HSM-99-71-31, ``Personal Sampler
Pump for Charcoal Tubes,'' September 15, 1972.
NIOSH Modification of NIOSH Method S-156
The NIOSH recommended method for low levels for acrylonitrile is a
modification of method S-156. It differs in the following respects:
(1) Samples are desorbed using 1 ml of 1 percent acetone in
CS2 rather than methanol.
(2) The analytical column and conditions are:
Column: 20 percent SP-1000 on 80/100 Supelcoport 10 feet x \1/8\
inch S.S.
Conditions:
Injector temperature: 200 [deg]C.
Detector temperature: 100 [deg]C.
Column temperature: 85 [deg]C.
Helium flow: 25 ml/min.
Air flow: 450 ml/min.
Hydrogen flow: 55 ml/min.
(3) A 2 [micro]l injection of the desorbed analyte is used.
(4) A sampling rate of 100 ml/min is recommended.
OSHA Laboratory Modification of NIOSH Method S-156
Analyte: Acrylonitrile.
Matrix: Air.
Procedure: Adsorption on charcoal, desorption with methanol, GC.
1. Principle of the Method (Reference 1).
1.1 A known volume of air is drawn through a charcoal tube to trap
the organic vapors present.
1.2 The charcoal in the tube is transferred to a small, stoppered
sample vial, and the analyte is desorbed with methanol.
1.3 An aliquot of the desorbed sample is injected into a gas
chromatograph.
1.4 The area of the resulting peak is determined and compared with
areas obtained for standards.
2. Advantages and disadvantages of the method.
2.1 The sampling device is small, portable, and involves no liquids.
Interferences are minimal, and most of those which do occur can be
eliminated by altering chromatographic conditions. The tubes are
analyzed by means of a quick, instrumental method.
2.2 This method may not be adequate for the simultaneous analysis of
two or more substances.
2.3 The amount of sample which can be taken is limited by the number
of milligrams that the tube will hold before overloading. When the
sample value obtained for the backup section of the charcoal tube
exceeds 25 percent of that found on the front section, the possibility
of sample loss exists.
2.4 The precision of the method is limited by the reproducibility of
the pressure drop across the tubes. This drop will affect the flow rate
and cause the volume to be imprecise, because the pump is usually
calibrated for one tube only.
3. Apparatus.
3.1 A calibrated personal sampling pump whose flow can be determined
within 5 percent at the recommended flow rate.
3.2 Charcoal tubes: Glass tube with both ends flame sealed, 7 cm
long with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40
mesh activated charcoal separated by a 2-mm portion of urethane foam.
The activated charcoal is prepared from coconut shells and is fired at
600 [deg]C prior to packing. The adsorbing section contains 100 mg of
charcoal, the back-up section 50 mg. A 3-mm portion of urethane foam is
placed between the outlet end of the tube and the back-up section. A
plug of sililated glass wool is placed in front of the adsorbing
section. The pressure drop across the tube must be less than one inch of
mercury at a flow rate of 1 liter per minute.
3.3 Gas chromatograph equipped with a nitrogen phosphorus detector.
3.4 Column (10-ft x 1/8