[Federal Register Volume 63, Number 59 (Friday, March 27, 1998)]
[Rules and Regulations]
[Pages 15006-15033]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-6999]



[[Page 15005]]

_______________________________________________________________________

Part II





Environmental Protection Agency





_______________________________________________________________________



40 CFR Parts 9 and 63



Aerospace Manufacturing and Rework Facilities; National Emission 
Standards for Hazardous Air Pollutants and Control Techniques Guideline 
Document for Source Categories; Final and Proposed Rules

  Federal Register / Vol. 63, No. 59 / Friday, March 27, 1998 / Rules 
and Regulations  

[[Page 15006]]



ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9 and 63

[AD-FRL-5978-4]
RIN 2060-AE02


National Emission Standards for Hazardous Air Pollutants and 
Control Techniques Guideline Document for Source Categories: Aerospace 
Manufacturing and Rework Facilities

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule and release of final control techniques guideline 
(CTG) document.

-----------------------------------------------------------------------

SUMMARY: This action finalizes several amendments to the national 
emission standards for hazardous air pollutants (NESHAP) for aerospace 
manufacturing and rework facilities proposed in the Federal Register on 
October 29, 1996 (61 FR 55842). The amendments include: Corrections to 
several references in the rule; revisions and additions to definitions; 
clarification of the applicability of the cleaning operations 
standards; clarification of the applicability of the rule to space 
vehicles; addition of standards for Type I chemical milling maskants; 
addition of a test method for determining the filtration efficiency of 
dry particulate filters; revision of standards for new and existing 
sources using dry particulate filters to control emissions from topcoat 
and primer application and depainting operations; addition of an 
exemption for certain water-reducible coatings; addition of an 
exemption from inorganic HAP requirements for hand-held spray can 
applications; addition of an essential use exemption for cleaning 
solvents; clarification of compliance dates; clarification of the 
applicability of new source MACT to spray booths; clarification and 
addition of emissions averaging provisions; revision of the 
requirements for new and existing primer and topcoat application 
operations; clarification of monitoring requirements for dry 
particulate filter usage; revision of the standard for depainting 
operations; addition of a cross reference to requirements in the 
General Provisions in subpart A of part 63; addition of appendix A to 
this subpart containing definitions for specialty coatings; 
miscellaneous changes to the proposed amendatory language; and minor 
technical corrections, including correction of the OMB tracking number 
in 40 CFR part 9 (Section 9.1), that were not part of the October 29, 
1996 proposal. Today's action takes final action on all of these 
amendments.

EFFECTIVE DATE: March 27, 1998.

ADDRESSES: Control Techniques Guideline. Copies of the final CTG may be 
obtained from the U. S. EPA Library (MD-35), Research Triangle Park, NC 
27711; telephone (919) 541-2777.
    An electronic version of documents from the Office of Air and 
Radiation (OAR) are available through EPA's OAR Technology Transfer 
Network Web site (TTNWeb). The TTNWeb is a collection of related Web 
sites containing information about many areas of air pollution science, 
technology, regulation, measurement, and prevention. The TTNWeb is 
directly accessible from the Internet via the World Wide Web at the 
following address, ``http://www.epa.gov/ttn''. Electronic versions of 
this preamble and rule are located under the OAR Policy and Guidance 
Information Web site, ``http://www.epa.gov/ttn/oarpg/'', under the 
Recently Signed Rules section. If more information on the TTNWeb is 
needed, contact the Systems Operator at (919) 541-5384.

FOR FURTHER INFORMATION CONTACT: For information concerning this notice 
and analyses performed in developing this rule, contact Ms. Barbara 
Driscoll, Policy Planning and Standards Group, Emission Standards 
Division (MD-13), U. S. Environmental Protection Agency, Research 
Triangle Park, NC 27711; telephone number (919) 541-0164. For 
implementation issues (guidance documents), contact Ms. Ingrid Ward, 
Program Review Group, Information Transfer and Program Integration 
Division (MD-12), U. S. Environmental Protection Agency, Research 
Triangle Park, NC 27711, telephone number (919) 541-0300. For 
information concerning applicability and rule determinations, contact 
your State or local representative or the appropriate EPA regional 
representative. For a listing of EPA regional contacts, see the 
following SUPPLEMENTARY INFORMATION section.

SUPPLEMENTARY INFORMATION:

Regulated Entities

    Entities potentially regulated by this action are owners or 
operators of facilities that are engaged, either in part or in whole, 
in the manufacturing or rework of commercial, civil, or military 
aerospace vehicles or components and that are major sources as defined 
in Sec. 63.2 of this part. Regulated categories include:

------------------------------------------------------------------------
           Category                  Examples of regulated entities     
------------------------------------------------------------------------
Industry.....................  Facilities that are major sources of     
                                hazardous air pollutants and            
                                manufacture, rework, or repair aircraft 
                                such as airplanes, helicopters,         
                                missiles, rockets, and space vehicles.  
Federal Government...........  Federal facilities that are major sources
                                of hazardous air pollutants and         
                                manufacture, rework, or repair aircraft 
                                such as airplanes, helicopters,         
                                missiles, rockets, and space vehicles.  
------------------------------------------------------------------------

This table is not intended to be exhaustive, but rather it provides a 
guide for readers regarding entities that EPA is now aware could 
potentially be regulated by this action. Other types of entities not 
listed in the table could also be regulated. To determine whether your 
facility [company, business, organization, etc.] is regulated by this 
action, you should carefully examine the applicability criteria in 
Sec. 63.741 of the NESHAP for aerospace manufacturing and rework 
facilities promulgated in the Federal Register on September 1, 1995 (60 
FR 45948). If you have questions regarding the applicability of this 
action to a particular entity, contact the appropriate regional 
representative:

Region I

NESHAP (MACT) Coordinator, U.S. EPA Region I, John F. Kennedy Federal 
Building, One Congress Street, Boston, MA 02203-001, (617) 565-3438

Region II

Umesh Dholakia or Yue-On Chiu, U.S. EPA Region II, 290 Broadway Street, 
New York, NY 10007-1866, (212) 637-4023 (Umesh), (212) 637-4065 (Yue-
On)

Region III

Bernard Turlinski, U.S. EPA Region III, 841 Chestnut Building, 
Philadelphia, PA 19107, (215) 566-2150

Region IV

Leonardo Ceron, U.S. EPA Region IV, Atlanta Federal Center, 61 Forsyth 
Street SW, Atlanta, GA 30303-3104, (404) 562-9129

[[Page 15007]]

Region V

Emmett Keegan, U.S. EPA Region V, 77 West Jackson Boulevard, Chicago, 
IL 60604-3507, (312) 886-0678

Region VI

Elvia Evering, U.S. EPA Region VI, First Interstate Bank Tower, @ 
Fountain Place, 1445 Ross Avenue, 12th Floor, Suite 1200, Dallas, TX 
75202-2733, (214) 665-7575

Region VII

Richard Tripp, U.S. EPA Region VII, Air Toxics Coordinator, 726 
Minnesota Avenue, Kansas City, KS 66101, (913) 551-7566

Region VIII

Heather Rooney, U.S. EPA Region VIII, Air Toxics Coordinator, 999 18th 
Street, Suite 500, Denver, CO 80202-2466, (303) 312-6971

Region IX

Nikole Reaksecker, U.S. EPA Region IX, Air Division-6, 75 Hawthorne 
Street, San Francisco, CA 94105, (415) 744-1187

Region X

Andrea Wullenweber, U.S. EPA Region X, Air Toxics Coordinator, 1200 
Sixth Avenue, Seattle, WA 98101, (206) 553-8760

    These amendments to the rule will not change the basic control 
requirements of the rule or the level of health protection it provides. 
The rule requires new and existing major sources to control emissions 
of hazardous air pollutants to the level reflecting application of the 
maximum achievable control technology.
    In addition, the EPA announces the availability of a final control 
techniques guideline (CTG) document for control of volatile organic 
compound (VOC) emissions from aerospace manufacturing and rework 
facilities. This document has been prepared in accordance with section 
183(b)(3) of the Clean Air Act Amendments of 1990 (the ``Act'') to 
assist States in analyzing and determining reasonably available control 
technology (RACT) for stationary sources of VOC emissions located 
within ozone national ambient air quality standard nonattainment areas. 
The final document recommends RACT for industries included in, but not 
limited to, 10 Standard Industrial Classification (SIC) codes: SIC 
3720, Aircraft and Parts; SIC 3721, Aircraft; SIC 3724, Aircraft 
Engines and Engine Parts; SIC 3728, Aircraft Parts and Equipment; SIC 
3760, Guided Missiles, Space Vehicles, and Parts; SIC 3761, Guided 
Missiles and Space Vehicles; SIC 3764, Space Propulsion Units and 
Parts; SIC 3769, Space Vehicle Equipment; SIC 4512, Scheduled Air 
Transportation; and SIC 4581, Airports, Flying Fields, and Services.
    (As of January 1, 1997, a new numerical coding system for 
classifying industries has been implemented by the U.S. Census Bureau. 
The new system is called the North American Industrial Classification 
System--NAICS. The following list of affected industries was developed 
as a cross-reference to the above SIC codes: NAICS 336411, Aircraft 
Manufacturing; NAICS 336412, Aircraft Engine and Engine Parts 
Manufacturing; NAICS 336413, Other Aircraft Part and Auxiliary 
Equipment Manufacturing; NAICS 336414, Guided Missile and Space Vehicle 
Manufacturing; NAICS 336419, Other Guided Missile and Space Vehicle 
Parts and Auxiliary Equipment Manufacturing; NAICS 481111, Scheduled 
Passenger Air Transportation; and NAICS 481112, Scheduled Freight Air 
Transportation.)
    The information presented below is organized as follows:

I. Background
    A. Public Comment on the October 29, 1996 Proposal
    B. Judicial Review
II. Summary of Major Comments and Changes to the Proposed Amendments 
to the Rule
    A. Corrections to References
    B. Definitions
    C. Cleaning Operations
    D. Applicability to Space Vehicles
    E. Standards for Type I Maskants
    F. Test Method for Determining Filtration Efficiency
    G. Standards for Dry Particulate Filters
    H. Exemption for Waterborne Coatings
    I. Exemption From Inorganic HAP Requirements for Hand-Held Spray 
Can Applications
    J. Essential Use Exemption for Cleaning Solvents
    K. Compliance Dates
    L. Requirements for New Affected Sources (Spray Booths)
    M. Emissions Averaging
    N. Requirements for New and Existing Primer and Topcoat 
Application Operations
    O. Monitoring Requirements for Dry Particulate Filter Usage
    P. Depainting Operations
    Q. Applicability of General Provisions
    R. Specialty Coatings
    S. Miscellaneous Changes
    T. Technical Corrections
III. Control Techniques Guideline
IV. Administrative Requirements
    A. Docket
    B. Paperwork Reduction Act
    C. Executive Order 12866
    D. Regulatory Flexibility Act
    E. Submission to Congress
    F. Unfunded Mandates Reform Act

I. Background

    National emission standards for hazardous air pollutants for 
aerospace manufacturing and rework facilities were proposed under 
Section 112(d) of the Clean Air Act Amendments of 1990 (the ``Act'') in 
the Federal Register on June 6, 1994 (59 FR 29216). Public comments 
were received regarding the standards and the final NESHAP was 
promulgated in the Federal Register on September 1, 1995 (60 FR 45948). 
After promulgation of the final rule, several issues were raised by 
various industry representatives and affected parties. Based on 
discussions with the commenters, the Agency proposed actions to amend 
Secs. 63.741, 63.742, 63.743, 63.744, 63.745, 63.746, 63.747, 63.749, 
63.750, 63.751, 63.752 and 63.753 of subpart GG of 40 CFR part 63. 
These sections deal with applicability, definitions, general standards, 
cleaning operations, topcoat and primer application operations, 
depainting operations, chemical milling maskant application operations, 
compliance dates and determinations, test methods and procedures, 
monitoring requirements, recordkeeping requirements, and reporting 
requirements. These changes provide additional flexibility to the 
regulated community and in several instances, clarify/correct errors in 
the regulatory text.

A. Public Comment on the October 29, 1996 Proposal

    Eighteen comment letters were received on the October 29, 1996 
Federal Register document that proposed changes to the rule. The 
proposed changes covered a variety of issues and many of the comment 
letters were supportive of the amendments. A few other comment letters 
also included suggested editorial revisions to further clarify some 
aspects of the proposed amendments or to address oversights in the 
proposed amendments. The EPA considered these suggestions and, where 
appropriate, made changes to the proposed amendments. The significant 
issues raised and the changes to the proposed amendments are summarized 
in this preamble. More detailed responses are provided in an addendum 
to the background information document (BID) volume II which can be 
found in Docket A-92-20, document No. EPA 453/R-97-003b. Some of the 
comment letters also included numerous issues not covered in the 
October 29, 1996 proposal. The EPA reviewed and responded to each of 
these in the addendum to the BID; any resulting changes to the final 
rule will

[[Page 15008]]

be proposed in a future Federal Register notice.

B. Judicial Review

    Under section 307(b)(1) of the Act, judicial review of today's 
amendments to the NESHAP for aerospace manufacturing and rework 
facilities is available only on the filing of a petition for review in 
the U.S. Court of Appeals for the District of Columbia Circuit within 
60 days of today's publication of this final rule. Under section 
307(b)(2) of the CAA, the requirements that are subject to today's 
notice may not be challenged later in civil or criminal proceedings 
brought by the EPA to enforce these requirements.

II. Summary of Major Comments and Changes to the Proposed 
Amendments to the Rule

A. Corrections to References

    In the September 1995 promulgated rule, there were several 
references to Sec. 63.751(b)(7)(iii), which only existed in an earlier 
draft of the promulgated rule. The EPA proposed the following revisions 
in October 1996: Sec. 63.751(b)(6)(ii)(A) of the promulgated rule 
references (b)(7)(iii)(A)(3), but should reference paragraph 
(b)(6)(iii)(A)(2); Sec. 63.751(b)(6)(iii) references (b)(7)(iii)(A), 
and (b)(7)(iii) (B) or (C), but should reference paragraphs 
(b)(6)(iii)(A), and (b)(6)(iii) (B) or (C); 
Sec. 63.751(b)(6)(iii)(A)(2) references (b)(7)(iii)(A)(1), but should 
reference paragraph (b)(6)(iii)(A)(1); Sec. 63.751(b)(6)(iii)(D) 
references (b)(7)(iii) (B) or (C), but should reference paragraph 
(b)(6)(iii) (B) or (C). There were no comments on these proposed 
revisions.

B. Definitions

    The October 29, 1996 Federal Register notice contained several 
definitions to be added to Sec. 63.742 and several to be revised, based 
on additional information submitted to the Agency after promulgation of 
the final rule. These changes are summarized below.
    The definition of cleaning solvent in the promulgated rule stated 
that ``cleaning solvent'' did not include solutions that contained 
``no'' HAP or VOC. Many aqueous cleaners contain negligible amounts of 
HAP or VOC. The EPA wants to encourage the use of these aqueous 
cleaners. Therefore, in October 1996 the EPA proposed the following 
language to exclude cleaners containing de minimis levels of HAP or VOC 
from the definition of cleaning solvent: ``Cleaning solvent means a 
liquid material used for hand-wipe, spray gun, or flush cleaning. This 
definition does not include solutions that contain HAP and VOC below 
the de minimis levels specified in Sec. 63.741(f) (e.g., water or 
acetone).'' The EPA also proposed to change the applicable portion of 
Sec. 63.741(f) to read: ``The requirements of this subpart also do not 
apply to primers, topcoats, chemical milling maskants, strippers, and 
cleaning solvents containing HAP and VOC at a concentration less than 
0.1 percent for carcinogens or 1.0 percent for noncarcinogens, as 
determined from manufacturer's representations.'' One commenter stated 
that not all HAP's are VOC's, nor are all VOC's HAP's. If the ``and'' 
is used, then one could read Sec. 63.741(f) to require both VOC's and 
HAP's to be present for an exemption to apply. The commenter 
recommended using ``and/or'' which is unacceptable because it would 
create an exemption when both HAP and VOC were present, but only one 
was below the specified level. It is not the Agency's position that 
both HAP and VOC need be present for the exemption described in 
Sec. 63.741(f) to apply.
    The proposed definition also contained a parenthetical reference to 
water or acetone as examples of substances that might be present at a 
de minimis level. One commenter stated the parenthetical reference to 
water or acetone is confusing and should be deleted. The EPA agreed and 
has revised the definition as follows:

    Cleaning solvent means a liquid material used for hand-wipe, 
spray gun, or flush cleaning. This definition does not include 
solutions that contain HAP and VOC below the de minimis levels 
specified in Sec. 63.741(f).

    The Agency also proposed adding a definition for antique aerospace 
vehicle or component so that these vehicles and components would be 
exempted from the regulation. One commenter supported the proposed 
definition. Another commenter suggested revising the definition to 
include those nonflight worthy aircraft intended for permanent display, 
or used for static manufacturing technology demonstrations. The 
commenter indicated that the definition in 14 CFR 45.22 is limited to 
operational, flight worthy aircraft used in exhibitions (motion 
pictures, television productions or air shows). The EPA believes that 
the passage to which the commenter refers actually concerns 
``exhibition'' rather than ``antique'' aircraft. It was not EPA's 
intent to add an exemption for exhibition aircraft that do not meet the 
``antique aircraft'' definition. In addition, EPA believes that it is 
not necessary to expand the scope of the ``antique aircraft'' 
definition because the Agency interprets the definition as including 
aircraft built at least 30 years ago that are not currently 
flightworthy. Therefore, EPA is promulgating the definition of antique 
aircraft as set forth in the proposal with some clarification (i.e., 
simplification) as follows:

    Antique aerospace vehicle or component means an aircraft or 
component thereof that was built at least 30 years ago. An antique 
aerospace vehicle would not routinely be in commercial or military 
service in the capacity for which it was designed.

    Due to the proposed addition of a standard for Type I chemical 
milling maskants, EPA proposed revising the definition for chemical 
milling maskant. One commenter noted that in the proposed definition, 
listed examples should be made identical to the listed names for these 
maskants found in appendix A to subpart GG. Another commenter raised 
the issue of exempting chemical milling maskants used for two different 
types of chemical milling applications. The commenter stated the same 
maskant can be used in aluminum chemical milling and titanium chemical 
milling, but these applications are not used on the same part or 
subassembly. A maskant used for both aluminum chemical milling and 
titanium chemical milling could not meet the low VOC content limits. In 
an existing plating shop which uses the same maskant tanks for two 
chemical milling applications, the proposed definition and associated 
maskant limits would require the addition of a new maskant tank to meet 
the low VOC maskant limit and another tank to meet the critical use 
applications. This might result in an increase in emissions since the 
surface area of the maskant in the tanks would double. The EPA agreed 
that the commenters' changes are reasonable because the purpose of the 
rule is to reduce HAP emissions and that adding a new maskant tank 
would likely increase HAP emissions in the aggregate. The definition 
has been revised as follows:

    Chemical milling maskant means a coating that is applied 
directly to aluminum components to protect surface areas when 
chemical milling the component with a Type I or Type II etchant. 
Type I chemical milling maskants are used with a Type I etchant and 
Type II chemical milling maskants are used with a Type II etchant. 
This definition does not include bonding maskants, critical use and 
line sealer maskants, and seal coat maskants. Additionally, maskants 
that must be used with a combination of Type I or Type II etchants 
and any of the above types of maskants (i.e., bonding, critical use 
and line sealer, and seal coat) are also exempt from this subpart. 
(See also Type I and Type II etchant definitions.)


[[Page 15009]]


    To further clarify the types of chemical milling maskants that are 
covered by the final rule, the Agency is providing the following 
separate definitions for Type I and Type II etchants:

    Type I etchant means a chemical milling etchant that contains 
varying amounts of dissolved sulfur and does not contain amines.
    Type II etchant means a chemical milling etchant that is a 
strong sodium hydroxide solution containing amines.

    A commenter provided example scenarios in which the current 
definition of self-priming topcoat is overly restrictive. The commenter 
further stated that self-priming topcoats should be recognized as 
topcoats and the topcoat VOC/HAP limits should apply, not the primer 
limits. The Agency did not agree that the described scenarios are 
likely to present any problems in determining the appropriate coating 
category. However, the Agency did agree that removing the last sentence 
from the definition which stated: ``The coating is not subsequently 
topcoated with any other product formulation'' does clarify the 
definition of self-priming topcoat and makes it more consistent with 
the definition of topcoat.
    Based on additional information received from industry, the EPA 
proposed in October 1996 to change or add the following definitions:

    Aircraft transparency means the aircraft windshield, canopy, 
passenger windows, lenses, and other components that are constructed 
of transparent materials.
    Chemical milling maskant application operation means application 
of chemical milling maskant for use with Type I or Type II chemical 
milling etchants.
    Closed-cycle depainting system means a dust-free, automated 
process that removes permanent coating in small sections at a time, 
and maintains a continuous vacuum around the area(s) being depainted 
to capture emissions.
    High volume low pressure (HVLP) spray equipment means spray 
equipment that is used to apply coating by means of a spray gun that 
operates at 10.0 psig of atomizing air pressure or less at the air 
cap.
    Specialty coating means a coating that, even though it meets the 
definition of a primer, topcoat, or self-priming topcoat, has 
additional performance criteria beyond those of primers, topcoats, 
and self-priming topcoats for specific applications. These 
performance criteria may include, but are not limited to, 
temperature or fire resistance, substrate compatibility, 
antireflection, temporary protection or marking, sealing, adhesively 
joining substrates, or enhanced corrosion protection. Individual 
specialty coatings are defined in appendix A to this subpart and in 
the CTG for Aerospace Manufacturing and Rework Operations (Document 
No. EPA 453/R-97-004).
    Waterborne (water-reducible) coating means any coating that 
contains more than 5 percent water by weight as applied in its 
volatile fraction.

No comments were received on these proposed definitions.
    Section 63.741(f) has also been modified to include Sec. 63.742 
(Definitions) in the list of additional specific exemptions from 
regulatory coverage.

C. Cleaning Operations

    Under the promulgated rule, the standards for cleaning operations 
could be read to apply to all cleaning operations at a facility, not 
only to cleaning operations that involve aerospace vehicles, 
components, or coating equipment. In order to clarify the applicability 
of the standards for cleaning operations, the Agency proposed to revise 
Sec. 63.741(c) to limit the applicability of the final rule to the 
manufacture or rework of aerospace vehicles or components. Other 
nonaerospace activities (e.g., general facility cleaning) are not 
subject to the requirements of this rule. No comments were received on 
this issue and EPA is promulgating the revisions as proposed.
    The EPA proposed to replace the word ``solvent'' with the defined 
term ``cleaning solvent'' for clarity and consistency in Sec. 63.744, 
paragraphs (a), (b), (c), and (e). The EPA has also changed the 
cleaning rag storage requirement by rewording the first sentence of 
Sec. 63.744(a)(1) as follows:

    Place cleaning solvent-laden cloth, paper, or any other 
absorbent applicators used for cleaning in bags or other closed 
containers upon completing their use.

    As originally promulgated, this NESHAP required that cleaning rags 
be stored immediately after use. In October 1996, EPA proposed to 
remove the word ``immediately'' from the sentence to make the rule more 
consistent from a temporal standpoint with the storage requirements 
contained in the California SIP-approved rules that were the basis for 
this requirement. No comments were received on these revisions. 
Accordingly, EPA decided to promulgate this change.
    In addition, the EPA has changed the requirements for flush 
cleaning to cover the situation in which an operator is cleaning 
multiple items at the same station, without leaving the station. The 
change to Sec. 63.744(d) is as follows: ``* * * empty the used cleaning 
solvent each time aerospace parts or assemblies, or components of a 
coating unit (with the exception of spray guns) are flush cleaned * * * 
.'' This change will better carry out the Agency's intent in regulating 
flush cleaning. No comments were received on this change.
    Based on information from industry, the EPA proposed a modification 
to the exemption in Sec. 63.744(e)(10). The revised text reads as 
follows:
    Cleaning of aircraft transparencies, polycarbonate, or glass 
substrates.
No comments were received on this revision.

D. Applicability to Space Vehicles

    Space vehicles (i.e., vehicles designed to travel beyond the limit 
of the earth's atmosphere) are specifically exempted from the 
requirements of this rule, except for the standards for depainting 
operations. The EPA proposed (1) removing the reference to these 
vehicles in Sec. 63.741(f) and (2) adding an additional specific 
exemption in a new paragraph, Sec. 63.741(h), to clarify the exemption. 
The EPA proposed Sec. 63.741(h) as follows:

    Regulated activities associated with space vehicles designed to 
travel beyond the limit of the earth's atmosphere, including but not 
limited to satellites, space stations, and the Space Shuttle System 
(including orbiter, external tanks, and solid rocket boosters), are 
exempt from the requirements of this subpart, except for depainting 
operations found in Sec. 63.746.

One commenter concurred with this revision as an important 
clarification of the applicability of the rule for aerospace 
organizations. The EPA decided to promulgate this change to the final 
rule.

E. Standards for Type I Maskants

    The EPA proposed to establish an emission limitation for Type I 
maskants and to include Type I maskants within the definition of 
chemical milling maskants. Pursuant to section 114 of the Act, 
information regarding maskants was requested from nine companies that 
own or operate aerospace manufacturing and rework facilities. 
Information was requested for all types of maskants, including total 
quantity used, formulation data, VOC and organic HAP content as 
received and as applied, substrate category and the composition of the 
metal alloy on which the maskant is applied, a listing of the type of 
parts or specific aircraft surfaces on which the maskant is used, VOC 
and HAP emissions from maskant application operations, and type(s) of 
controls (if any). The information received on Type I maskants was used 
to calculate a MACT floor. The MACT floor was determined to be the 
weighted (by usage volume) average HAP emissions from the sources, 622 
grams per liter [g/L] (5.2 pounds per gallon [lb/gal]).

[[Page 15010]]

    The EPA proposed revising Sec. 63.747(c) to include organic HAP and 
VOC content limits of 622 grams per liter (g/L) (5.2 pounds per gallon 
[lb/gal]) as the standard for uncontrolled Type I chemical milling 
maskants. The EPA proposed revising paragraphs (c)(1) and (2) to 
specify that the organic HAP and VOC limits of 160 g/L (1.3 lb/gal) 
apply only to Type II chemical milling maskants. One commenter 
supported EPA's proposed limits and stated the proposed Type I limit 
recognizes that some chemical etching applications require the use of 
solvent-based maskants, while still achieving a significant reduction 
in VOC and HAP emissions from masking operations.
    Due to the addition of a standard for Type I chemical milling 
maskants, EPA also proposed removing the definition of Type I maskants 
from the list of specialty coatings in appendix A of this subpart and 
revising the definition for chemical milling maskant in Sec. 63.742 of 
the promulgated rule. No comments were received on deletion of the 
definition for Type I maskants from Appendix A, and comments received 
on the definition for chemical milling maskant are discussed under 
definitions in Section II.B of this preamble.

F. Test Method for Determining Filtration Efficiency

    The Agency proposed a test method, Method 319, for the 
determination of filtration efficiency for paint overspray arresters 
(also referred to as particulate filters). The Agency proposed that 
this method be used by filter manufacturers to certify their filter 
efficiency. Commenters raised several issues related to the technical 
validity of proposed Method 319 and who could run the test. Based on 
these comments, the Agency has modified Sec. 63.750(o) to state that 
this method can be used by filter manufacturers or distributors, paint/
depainting booth suppliers, or owners or operators of affected sources 
to certify the efficiency of their filters for meeting the dry 
particulate filter requirements in today's amendments.
    The EPA also proposed filter efficiency tables (Tables 1, 2, 3, and 
4 of Sec. 63.745) and one commenter recommended adding descriptive 
language to the table headings. The EPA added ``for existing sources'' 
or ``for new sources'' to each of the table headings in response to the 
comment.

Table 1 of Sec.  63.745.--Two-Stage Arrestor; Liquid Phase Challenge for
                            Existing Sources                            
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>90........................................  >5.7                       
>50........................................  >4.1                       
>10........................................  >2.2                       
------------------------------------------------------------------------


 Table 2 of Sec.  63.745.--Two-Stage Arrestor; Solid Phase Challenge for
                            Existing Sources                            
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>90........................................  >8.1                       
>50........................................  >5.0                       
>10........................................  >2.6                       
------------------------------------------------------------------------


 Table 3 of Sec.  63.745.--Three-Stage Arrestor; Liquid Phase Challenge 
                             for New Sources                            
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>95........................................  >2.0                       
>80........................................  >1.0                       
>65........................................  >0.42                      
------------------------------------------------------------------------


  Table 4 of Sec.  63.745.--Three-Stage Arrestor; Solid Phase Challenge 
                             for New Sources                            
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>95........................................  >2.5                       
>85........................................  >1.1                       
>75........................................  >0.70                      
------------------------------------------------------------------------

    Three commenters raised several issues related to test Method 319 
and disagreed with specifics of the test method. All of the issues are 
addressed in the Agency's documented responses in Section 2.9 of the 
Addendum to the BID (Volume II), Document No. EPA 453/R-97-003b. In 
summary, Method 319 will retain use of oleic acid and potassium 
chloride (KCl) challenge aerosols. By selecting oleic acid and KCl as 
simulants for wet and dry overspray, the amount of testing needed is 
reduced because only two challenge materials are used, particle sizing 
accuracy is maintained, and safety and handling issues associated with 
volatile paint components are avoided.
    The method has been revised to allow additional flexibility for 
alternate duct configurations. The 180 degree bend in the duct has been 
made optional thereby allowing use of a straight duct. Also, the 
measurement procedures have been revised to allow the use of two 
particle counters to allow simultaneous sampling (one sampling upstream 
and one sampling downstream). Additionally, the NESHAP retains equal 
requirements for ``paint overspray arrestors'' under Sec. 63.745 Primer 
and Topcoat Application Operations, and ``particulate'' filters under 
Sec. 63.746 Depainting Operations.

G. Standards for Dry Particulate Filters

    The Agency proposed to revise MACT requirements for the control of 
inorganic particulates from certain primer, topcoat, and depainting 
operations. Based on a review of the available data, the EPA proposed 
requiring existing sources using particulate filters in depainting as 
well as topcoat and primer operations, in which any of the coatings 
contain inorganic HAP, to meet the filtration efficiency established 
for the two-stage system that was tested. Specifically, the Agency 
proposed requiring owners or operators of existing sources to use 
particulate filters that are certified under Sec. 63.750(o) to meet or 
exceed the efficiency data in Tables 1 and 2 of Sec. 63.745 (developed 
from the two-stage filter testing). The Agency has modified this 
language to indicate certification must be consistent with 
Sec. 63.750(o); therefore, this method can be used by filter 
manufacturers or distributors, paint/depainting booth suppliers, and/or 
owners or operators of affected sources to certify the efficiency of 
their filters.
    The Agency also proposed that new sources meet the filtration 
efficiency data points for the three-stage system that was tested. 
Specifically, the Agency proposed requiring owners or operators of new 
sources to use particulate filters that are certified under 
Sec. 63.750(o) to meet or exceed the efficiency data in Tables 3 and 4 
of Sec. 63.745 (developed from the three-stage filter testing). These 
new filtration requirements reflect a performance based standard rather 
than specified equipment, thus allowing more flexibility for affected 
sources to comply with the NESHAP.
    One commenter believed that test Method 319 is flawed and therefore 
questioned the filter efficiency limits

[[Page 15011]]

developed using testing based on Method 319. The Agency disagrees with 
the commenter and believes the filter efficiency limits to be 
technically based as equivalent to MACT. The test method is based on 
several years of work performed for EPA and culminated in testing of 
the two- and three-stage paint arrestors determined to represent MACT 
for the aerospace industry.
    In announcing these revised MACT requirements for particulate 
emissions, the Agency realizes that there are unique circumstances in 
which owners and operators have commenced construction or 
reconstruction of a new spray booth or hangar after the proposed 
regulation (June 4, 1994) and have had to comply with the requirements 
in the promulgated rule (September 1, 1995). For these owners or 
operators of aerospace manufacturing or rework operations who have 
commenced construction or reconstruction of new spray booth or hanger 
for inorganic HAP depainting operations, primer, or topcoat operations 
after June 4, 1994 but prior to October 29, 1996, the EPA has provided 
the flexibility to meet either the requirements for new sources under 
Sec. 63.745(g)(2)(ii) of the amendments to the final regulation found 
in today's notice or the requirements for new sources under 
Sec. 63.45(g)(2)(iv) of the September 1, 1995 promulgated rule which 
are found in Sec. 63.745(g)(2)(iii) in the amended rule. Sources that 
commenced construction prior to June 4, 1994 are still required to meet 
the existing source requirements for depainting operations and painting 
(topcoat or primer application) operations found in the final amended 
rule.

H. Exemption for Waterborne Coatings

    The EPA proposed that any waterborne coating for which the 
manufacturer's supplied data demonstrate that the coating meets the 
organic HAP and VOC content limits for its coating type as specified in 
the regulation be exempt from many of the organic HAP and VOC related 
requirements of this regulation. If the manufacturer's supplied data 
indicate that the waterborne coating meets the organic HAP and VOC 
content emission limits for its coating type, as specified in 
Secs. 63.745(c) and 63.747(c), then the owner or operator would not be 
required to demonstrate compliance for these coatings using the test 
method specified in Sec. 63.750(c). However, the owner or operator 
would still be required to maintain purchase records and manufacturer's 
supplied data sheets for exempt coatings. Owners or operators of 
facilities using waterborne coatings would also be required to handle 
and transfer these coatings in a manner that minimizes spills, apply 
these coatings using one or more of the specified application 
techniques, and comply with inorganic HAP emission requirements. This 
exemption was added as Sec. 63.741(i) as follows:

    Any waterborne coating for which the manufacturer's supplied 
data demonstrate that organic HAP and VOC contents are less than or 
equal to the organic HAP and VOC content limits for its coating 
type, as specified in Secs. 63.745(c) and 63.747(c), is exempt from 
the following requirements of this subpart: Secs. 63.745(d)-(e), 
63.747(d)-(e), 63.749(d) and (h), 63.750(c)-(h) and (k)-(m), 
63.752(c) and (f), and 63.753(c) and (e). A facility shall maintain 
the manufacturer's supplied data and annual purchase records for 
each exempt waterborne coating readily available for inspection and 
review, and shall retain these data for 5 years.

Section 63.741(f) was also modified to include Sec. 63.741(i) in the 
list of additional specific exemptions from regulatory coverage.
    The Agency proposed this exemption to streamline and simplify the 
requirements for owners and operators of facilities using these 
coatings and to encourage the use of waterborne coatings which may 
result in lower emissions than other coating types. No comments were 
received on this issue and EPA decided to promulgate this change.

I. Exemption From Inorganic HAP Requirements for Hand-Held Spray Can 
Applications

    Two commenters noted that the final rule created a point of 
confusion over the absence of an exemption from inorganic HAP 
requirements for the use of hand-held spray cans used outside a paint 
booth or hangar (i.e., touch-up operations). The Agency noted that such 
an exemption currently exists under Sec. 63.745(f)(3)(v) for primers 
and topcoats containing organic HAP or VOC, and the requirements for 
touch-up operations would also provide an exemption for these 
activities when conducted outside of the hangar or paint booth. 
However, the Agency agreed with the commenters that potential confusion 
could result in the absence of a clear exemption under the inorganic 
HAP requirements. Therefore, the Agency has added the following 
paragraph (x) to the list of operations in Sec. 63.745(g)(4) not 
subject to the requirements of paragraphs 63.745 (g)(1) through (g)(3):

    (x) The use of hand-held spray can application methods.

J. Essential Use Exemption for Cleaning Solvents

    In accordance with the Montreal Protocol on Substances that Deplete 
the Ozone Layer (``Montreal Protocol''), EPA has granted essential use 
allowances for limited applications of ozone depleting substances 
(ODS's). The EPA proposed that an essential use exemption be added to 
this rule for cleaning operations that have been identified as 
essential uses. The proposed language has been revised slightly for 
greater consistency with the stratospheric ozone regulations. The 
exemption was added as Sec. 63.744(e)(13) as follows:

    Cleaning operations identified as essential uses under the 
Montreal Protocol for which the Administrator has allocated 
essential use allowances or exemptions in 40 CFR 82.4.

One commenter concurred with EPA on this added exemption and EPA 
decided to promulgate this change.

K. Compliance Dates

    The EPA wishes to clarify an inconsistency between the preamble to 
the final rule and the regulation. The preamble to the final aerospace 
NESHAP states, ``Owners or operators of new commercial, civil, or 
military aerospace OEM and rework operations with initial startup after 
September 1, 1998 will be required to comply with all requirements upon 
startup.'' This statement is incorrect. The text of the promulgated 
regulation correctly states that new sources, with initial startup on 
or after September 1, 1995, must comply with all requirements upon 
startup. In October 1996, the EPA also proposed to clarify that the 
deadline for approval of an alternate control device is 120 days prior 
to the compliance date. This clarification, mistakenly omitted from the 
published final rule, is now reflected in Sec. 63.743(c). No comments 
were received on this issue and, thus, EPA decided to promulgate this 
change.

L. Requirements for New Affected Sources (Spray Booths)

    The Agency has clarified the requirements for new affected sources. 
An affected source is an emission unit, process, or operation 
identified in the NESHAP that is part of the entire facility, but is 
not necessarily a major source. In today's action the Agency is 
clarifying its intent that for inorganic HAP emissions, each spray 
booth or hangar that contains a primer or topcoat application operation 
subject to Sec. 63.745(g) or a depainting operation

[[Page 15012]]

subject to Sec. 63.746(b)(4) is considered an affected source and has 
added this description under Sec. 63.741(c). To avoid any 
inconsistency, the Agency has also added the words ``For organic HAP or 
VOC emissions'' at the beginning of Sec. 63.741(c) (2), (3), and (4). 
If such an affected source is constructed or reconstructed after 
October 29, 1996, then that spray booth or hangar must comply with the 
applicable inorganic HAP control requirements. Construction or 
reconstruction of a new spray booth or hangar at a facility with an 
existing coating or depainting operation will not cause the existing 
operation to be subject to any other new source standards; only the new 
spray booth or hangar will be subject to the applicable new source 
requirements for inorganic HAP and will need to comply upon the 
effective date of the requirements or startup, whichever is later. The 
EPA is also making this clarification in Sec. 63.749(a), the compliance 
dates and determinations section of the final rule.
    In addition, EPA also clarified that Sec. 63.5(b)(3) of the General 
Provisions, which requires advance notice and approval by the Agency 
prior to construction or reconstruction of a major affected source, 
shall apply to the construction or reconstruction of a new spray booth 
or hangar at a facility for an existing coating or depainting operation 
only if the booth or hangar has the potential to emit 10 tons/yr or 
more of an individual inorganic HAP or 25 tons/yr or more of all 
inorganic HAP combined. Owners or operators of an existing coating or 
depainting operation who construct or reconstruct a new booth or hangar 
that emit or have the potential to emit less than 10/25 tons/yr of 
inorganic HAP's will only be required to submit an annual notification 
on or before March 1 of each year. This annual notification shall 
include all of the information required in Sec. 63.5(b)(4) for each 
such booth or hangar constructed or reconstructed in the prior calendar 
year, except that the information shall be limited to the inorganic 
HAP's from the new booth or hangar. Of course, any owner or operator 
that constructs or reconstructs a new spray booth or hangar at a 
facility at which there is no existing coating or depainting operation 
will be required to comply with all of the applicable notice and 
advance approval requirements of Sec. 63.5.

M. Emissions Averaging

    Under the September 1, 1995 promulgated rule the averaging of 
emissions was permitted to occur within coating types (i.e., topcoats, 
primers, or maskants). The EPA also indicated at that time in the 1995 
background information document that EPA would be investigating options 
with respect to implementing a broad-based averaging scheme as a 
compliance option for the Aerospace NESHAP. Based on additional 
discussion in roundtable meetings, the EPA proposed in the October 29, 
1996 amendments to consolidate the language dealing with the averaging 
of emissions as it applies to the aerospace industry. Paragraphs 
63.745(e)(2) and 63.747(e)(2) were consolidated into a new 
Sec. 63.743(d), which, if promulgated as proposed, would have permitted 
averaging across coating types.
    In response to the October 1996 proposal, the EPA received two 
comments that supported the changes to the averaging provisions. One 
commenter indicated that introductory text was needed to clarify the 
intent of Sec. 63.743(d), which is where the averaging provisions are 
now located. The EPA agrees with the commenter and has added 
introductory language to Sec. 63.743(d). Another commenter wanted the 
averaging provisions to be expanded to include controlled operations 
(i.e., those with control devices). The EPA believes that as currently 
allowed, the averaging of uncontrolled coatings will encourage 
development and use of lower HAP and VOC content coatings in the 
aerospace industry. In order to preserve the environmental benefit of 
pollution prevention, EPA will not extend the averaging system to 
include controlled coatings.
    With regards to an expanded emissions averaging scheme, the EPA 
looked at various ways to expand the averaging provisions in the 
September 1995 promulgated rule so as to allow averaging between 
certain coating types. In designing emissions trading and averaging 
systems, EPA believes that it is important to consider the effect that 
trading or averaging is likely to have on facilities' actual emissions, 
as well as the effect on facilities' maximum allowable emissions. A 
workable scheme for averaging across coating types was not developed 
because the format of the coating limits in the rule as originally 
promulgated creates inherent difficulties in making equitable 
comparisons/calculations of actual emissions from coating categories 
with different limits. In order to include effective emissions 
averaging provisions for different coating categories (e.g., primers, 
topcoats, and maskants) or other emission sources, the format of the 
entire rule would have to be overhauled. Such changes are now beyond 
the scope of the work involved in finalizing these amendments to the 
aerospace rule.

N. Requirements for New and Existing Primer and Topcoat Application 
Operations

    The September 1, 1995 promulgated NESHAP requires owners or 
operators of primer and topcoat application operations who wish to use 
an alternative application method (other than HVLP or electrostatic 
spray) to demonstrate that the emissions generated during the initial 
30-day period, the period of time required to apply primer to five 
completely assembled aircraft, or a time period approved by the 
permitting agency are less than or equal to the emissions generated 
using HVLP or electrostatic spray application methods. Since 
promulgation, the Agency has received comments from industry concerning 
the test method for alternative spray equipment application requiring 
actual production trials. Those concerns involved the use of 
ineffective application equipment on actual production parts or 
assemblies which could lead to product quality and safety issues with 
significant cost to the manufacturer. The Agency has acknowledged those 
concerns and provided additional flexibility to owners or operators of 
primer and topcoat application operations seeking to use alternative 
application methods.
    The October 1996, proposed amendments to the final NESHAP in 
Sec. 63.750(i)(2)(ii) allowed owners or operators an alternative 
approach whereby the proposed application method is tested against 
either HVLP or electrostatic spray application methods in a laboratory 
or pilot production area, using parts and coatings representative of 
the process(es) in which the alternative method is to be used. Under 
this alternative, the laboratory test will use the same part 
configuration(s) and the same number of parts for both the proposed 
method and the HVLP or electrostatic spray application methods. The 
Agency intended to make the laboratory test an additional option 
instead of replacing the production evaluation in the final rule. 
Therefore, since no comments were received on the proposed revision to 
Sec. 63.750(i)(2)(ii), the Agency decided to promulgate this change by 
designating the proposed Sec. 63.750(i)(2)(ii) as 
Sec. 63.750(i)(2)(iii). For consistency, this change has also been made 
to Sec. 63.749 (d)(3)(iii)(B) and (d)(4)(iii)(B).

O. Monitoring Requirements for Dry Particulate Filter Usage

    The Agency proposed to clarify the monitoring requirements for 
owners or operators of depainting and painting

[[Page 15013]]

operations using dry particulate filters and HEPA filters to comply 
with this NESHAP. The EPA proposed to add language to Sec. 63.751(c)(1) 
to clarify that owners or operators are required to read and record 
monitoring (i.e., pressure drop) data only once per shift.
    One commenter requested that the phrase ``continuously monitor'' in 
Sec. 63.745(g)(2)(v) be changed to ``monitor once per shift'' to avoid 
confusion with the Agency's clarification of monitoring requirements in 
other sections of the final rule. Past experience with such control 
systems indicates that reading the designated operating parameter once 
per shift is sufficient for this system to be considered continuously 
monitored. The Agency believes that the systems should be continuously 
monitored by some mechanism, but that reading and recording the data 
should be required only once per shift. Therefore, the EPA has changed 
the cited text in Sec. 63.745 (g)(2)(iv)(C) and (g)(2)(v) to match 
monitoring requirements in other sections of the final rule.

P. Depainting Operations

    Based on numerous comments on the depainting operation standard, 
the EPA proposed a clarification to Sec. 63.746. The promulgated 
standard was presented in terms of volume (gallons) of organic HAP-
containing chemical strippers per aircraft. Because the NESHAP is 
specific to HAP, in October 1996 the EPA proposed changing the units of 
the standard and stating the requirements in terms of weight (pounds) 
of organic HAP per aircraft. The proposed standard was meant to be 
equivalent in terms of actual HAP emissions to the atmosphere and was 
based on assumptions concerning typical HAP contents of chemical 
strippers. The proposed limits allowed greater flexibility to the owner 
or operator of a new or existing depainting operation in selecting 
materials to perform spot stripping and decal removal.
    Based on comments involving technical arguments both for and 
against the different units for the spot stripping and decal removal 
allowance, the EPA decided to include both types of units and allow 
operators to decide which units they want to use and document their 
decision in their initial notification and/or operating permit. 
Accordingly, the EPA is promulgating the spot stripping and decal 
removal allowance in Sec. 63.746(b)(3) as follows:

    Each owner or operator of a new or existing depainting operation 
shall not, on an annual average basis, use more than 26 gallons of 
organic-HAP containing chemical strippers or alternatively 190 
pounds of organic HAP per commercial aircraft depainted; or more 
than 50 gallons of organic HAP-containing chemical strippers or 
alternatively 365 pounds of organic HAP per military aircraft 
depainted for spot stripping and decal removal.

    One commenter noted an apparent error in the proposed revision of 
Equation 20 and provided corrected definitions for the revised terms in 
the corrected equation. The EPA has incorporated those corrections in 
the final rule, as well as provided both equations to calculate the 
average annual volume of organic HAP-containing chemical stripper 
(Equation 20) or average annual weight of organic HAP (newly designated 
Equation 21) used for spot stripping and decal removal.
    Accordingly, the EPA has also revised Equation 21 in 
Sec. 63.750(j)(3) as follows:
[GRAPHIC] [TIFF OMITTED] TR27MR98.000

Where:

C=annual average weight (lb per aircraft) of organic HAP (chemical 
stripper) used for spot stripping and decal removal.
m=number of organic HAP contained in each chemical stripper, as 
applied.
n=number of organic HAP-containing chemical strippers used in the 
annual period.
Whi=weight fraction (expressed as a decimal) of each organic 
HAP (i) contained in the chemical stripper, as applied, for each 
aircraft depainted.
Dhi=density (lb/gal) of each organic HAP-containing chemical 
stripper (i) used in the annual period.
Vsi=volume (gal) of organic HAP-containing chemical stripper 
(i) used during the annual period.
A=number of aircraft for which depainting operations began during the 
annual period.

    Another commenter noted a typographical error in the proposed 
revision to the spot stripping and decal removal allowance in 
Sec. 63.749(f)(3)(ii)(A). The Agency has incorporated the corrected 
text into the final amendment.

Q. Applicability of General Provisions

    The EPA proposed in October 1996 the addition of Table 1: General 
Provisions' Applicability to subpart GG, in order to clarify the 
applicability of the General Provisions to this rule. Table 1 is 
referenced in Sec. 63.741 and is located at the end of the final rule 
text. No comments were provided on this issue.

R. Specialty Coatings

    In appendix A to this subpart, the EPA proposed to revise the last 
sentence of the definition of adhesive bonding primer to state: ``There 
are two categories of adhesive bonding primers: primers with a design 
cure at 250 deg.F or below and primers with a design cure above 
250 deg.F.'' This revision is a clarification that was omitted in the 
final rule.
    Two commenters suggested that the specialty coating definitions be 
reviewed and one of the commenters further suggested that the following 
specialty coating categories be added:

    Bearing coating--a coating applied to an antifriction bearing, a 
bearing housing, or the area adjacent to such a bearing in order to 
facilitate bearing function or to protect base material from 
excessive wear. A material shall not be classified as a bearing 
coating if it can also be classified as a dry lubricative material 
or a solid film lubricant.
    Dry lubricative material--a coating consisting of lauric acid, 
cetyl alcohol, waxes, or other non-cross linked or resin-bound 
materials which acts as a dry lubricant.
    Caulking and smoothing compounds--semi-solid materials which are 
applied by hand application methods and are used to aerodynamically 
smooth exterior vehicle surfaces or fill cavities such as bolt hole 
accesses. A material shall not be classified as a caulking and 
smoothing compound if it can also be classified as a sealant.

    These coating categories have been used by the San Diego and/or 
South Coast (California) Air Quality Management Districts in their 
aerospace coating regulations. Therefore, the Agency has incorporated 
these definitions into appendix A to subpart GG (and has also 
incorporated the suggested definitions and the corresponding VOC limits 
into the final CTG document). The Agency has also deleted the 
definitions for conformal coatings, protective oils/waxes, and space 
vehicle coatings from appendix A to subpart GG to be consistent with 
the CTG. Other commenters found typographical errors or areas for 
clarification involving the definitions of ``electric or radiation-
effect coating,'' ``pretreatment coatings,'' and ``wet fastener 
installation coating'' which have been corrected in these final 
amendments.

S. Miscellaneous Changes

    The EPA also made a number of minor changes to several sections of 
the October 1996 proposal based on public comments. One commenter 
requested the removal of the prohibition on use of ozone-depleting 
substances from Sec. 63.744. The control of HAP and ozone-depleting 
substances are under two

[[Page 15014]]

separate programs; hence, the EPA has deleted the reference to ozone-
depleting substances in Table 1 of Sec. 63.744.
    Another commenter noted that the table numbering in proposed 
Sec. 63.750(o) was incorrect. The Agency has corrected the text to 
state ``* * * found in Tables 1 and 2, or 3 and 4 of Sec. 63.745 for 
existing and new sources respectively.''
    Two commenters noted there should be a reference to the term 
``Hi'' in Sec. 63.750(k) since Sec. 63.749(h)(3)(i) cites 
this section for the method to determine Hi. The Agency has 
clarified Sec. 63.750(k) by adding the term Hi to the stated 
definition at the end of the paragraph.

T. Technical Corrections

    The following amendments are technical corrections that were not 
part of the October 29, 1996 proposal. These changes are being made as 
part of today's action as a matter of efficiency in rulemaking. 
Furthermore, these changes are noncontroversial and do not 
substantively change the requirements of the rule. By promulgating 
these technical corrections directly as a final rule, the EPA is 
foregoing an opportunity for public comment on a notice of proposed 
rulemaking. Section 553(b) of title V of the United States Code and 
section 307(b) of the CAA permit an agency to forego notice and comment 
when ``the agency for good cause finds (and incorporates the finding 
and a brief statement of reasons therefore in the rules issued) that 
notice and public procedure thereon are impracticable, unnecessary, or 
contrary to the public interest.'' The EPA finds that notice and 
comment regarding these technical corrections are unnecessary due to 
their noncontroversial nature and because they do not change the 
requirements of the final rule. The EPA finds that this constitutes 
good cause under 5 U.S.C. Sec. 553(b) for a determination that the 
issuance of a notice of proposed rulemaking is unnecessary.
1. Clarification of the Definition of Coating
    The word ``protective'' was added to the definition of ``coating'' 
in Sec. 63.742 to be consistent with other surface coating regulations 
and CTG's.
2. Addition of the Definition of Recovery Device
    Two commenters requested that the term ``dedicated solvent recovery 
device'' be defined in the rule so that proper test procedures may be 
followed. The Agency has included the following definition for 
``recovery device'' in Sec. 63.742 which is based on the definition 
from the HON:

    Recovery device means an individual unit of equipment capable of 
and normally used for the purpose of recovering chemicals for fuel 
value, use, or reuse. Examples of equipment that may be recovery 
devices include absorbers, carbon adsorbers, condensers, oil-water 
separators, or organic-water separator or organic removal devices 
such as decanters, strippers, or thin-film evaporation units.

A dedicated solvent recovery device refers to such control equipment 
(as described/defined above) that is specific to a given process or 
control system.
3. Correction of Cited Reference to Table 1 of this Section in 
Sec. 63.744(a), (b)(1), and (d)
    The numbering format for several tables in the promulgated rule was 
erroneous and confusing. The table reference in Sec. 63.744(a),(b)(1), 
and (d) has been corrected to read: ``Table 1 of this section.''
4. Clarification of Requirements in Sec. 63.744(c)
    Several questions have been raised related to spray gun cleaning 
using water as the cleaning solvent. Language was added to the 
introductory text at the end of Sec. 63.744(c) stating that spray gun 
cleaning operations using cleaning solvent solutions that contain HAP 
and VOC below the de minimis levels specified in Sec. 63.741(f) are 
exempt from the subsequent requirements in paragraphs (c)(1) through 
(c)(4).
5. Clarifications to Sec. 63.745(e) and (f)
    All references to topcoat(s) or topcoat application operations 
include self-priming topcoats. The parenthetical phrase ``(including 
self-priming topcoats)'' was added to all applicable paragraphs in 
Sec. 63.745 (e) and (f) for clarification and consistency with 
Sec. 63.745(c)(3) and (c)(4). In Sec. 63.745(f)(1), the reference to 
application techniques specified in paragraphs (f)(1)(i) through 
(f)(1)(viii) has been corrected to read ``(f)(1)(i) through 
(f)(1)(ix).''
6. Clarification to Sec. 63.746(a)
    The words ``or rework'' were added to the last sentence in 
Sec. 63.746(a) to clarify that all aerospace facilities (manufacturing 
or rework) that depaint six or less completed aerospace vehicles in a 
calendar year are exempt from this section.
7. Clarification of Language in Sec. 63.746(c)(1)
    The wording in Sec. 63.746(c)(1) was changed to three separate 
paragraphs (paragraphs (c) (2) and (3) were added) to clarify the 
procedures to be used in determining compliance with the control 
efficiency (95 percent) for new control systems. The 
language has been clarified to describe how the control efficiencies 
are determined involving the capture and destruction or removal 
efficiencies and may take into account the volume of chemical stripper 
used (relative to baseline applications) and is consistent with the 
example provided.
8. Correction of Equation to Determine the Composite Vapor Pressure in 
Sec. 63.750(b)(2)
    A summation sign was added in front of the second term of the 
denominator (involving ``We'') of the equation used to 
determine the composite vapor pressure of hand-wipe cleaning solvents.
9. Correction of OMB Tracking Number
    In compliance with the Paperwork Reduction Act (PRA), this 
technical correction amends the table that lists the Office of 
Management and Budget (OMB) control numbers issued under the PRA for 
this final rule.
    The EPA is today amending the table in 40 CFR part 9 (Section 9.1) 
of currently approved information collection request (ICR) control 
numbers issued by OMB for various regulations. The affected regulations 
are codified at 40 CFR part 63 subpart GG, sections 63.752 and 63.753 
(recordkeeping and reporting requirements, respectively). The correct 
OMB control (tracking) number for this final rule is 2060-0314.
    This ICR was previously subject to public notice and comment prior 
to OMB approval. As a result, EPA finds that there is ``good cause'' 
under section 553(b)(B) of the Administrative Procedure Act (5 U.S.C. 
553(b)(B)) to amend this table without prior notice and comment. Due to 
the technical nature of the table, further notice and comment would be 
unnecessary.

III. Control Techniques Guideline

    Today's action includes the final issuance of the control 
techniques guideline(CTG) whose availability in draft form was 
announced in the Federal Register on October 29, 1996 (61 FR 55842). 
There were several comments involving the draft CTG submitted with 
other comments on the proposed NESHAP amendments. Most of those 
comments involved specialty coating category definitions and their 
associated VOC limits. One commenter who suggested adding three new 
coating category definitions (discussed previously in section Q) also 
raised several other concerns involving the proposed definitions and/or 
associated limits for clear coatings, lacquers, and specialized 
function coatings. Since the specialty coating limits are meant to

[[Page 15015]]

reflect baseline levels nationwide, and will have no significant impact 
on emission reductions, the EPA has decided to maintain the proposed 
definitions and associated limits for these coating categories.
    Under the Clean Air Act, as amended in 1990 (the ``Act''), State 
implementation plans (SIP's) for ozone nonattainment areas (except 
marginal areas) must be revised to require reasonably available control 
technology (RACT) for sources for which the EPA publishes a CTG between 
November 15, 1990 and the date an area achieves attainment status (the 
Act, Sec. 182(b)(2), (c), (d), (e)). The EPA has defined RACT as ``the 
lowest emission limitation that a particular source is capable of 
meeting by the application of control technology that is reasonably 
available considering technological and economic feasibility'' (44 FR 
53761, 53762, September 17, 1979).
    The CTG's review current knowledge and data concerning the 
technology and costs of various emissions control techniques. The CTG's 
are intended to provide State and local air pollution authorities with 
an information base for proceeding with their own analyses of RACT to 
meet statutory requirements.
    Each CTG contains a ``presumptive norm'' for RACT for a specific 
source category, based on the EPA's evaluation of the capabilities and 
problems general to the category. Where applicable, the EPA recommends 
that States adopt requirements consistent with the presumptive norm. 
However, the presumptive norm is only a recommendation. States may 
choose to develop their own RACT requirements on a case-by-case basis, 
considering the emission reductions needed to achieve the national 
ambient air quality standards and the economic and technical 
circumstances of the individual source.
    This CTG is issued pursuant to Clean Air Act Sec. 183(b)(3), which 
requires issuance of a CTG to reduce VOC emissions from aerospace 
coatings and solvents. It addresses RACT for control of VOC emissions 
from aerospace manufacturing and rework facilities. Volatile organic 
compound emissions from primer, topcoat, and ``specialty'' coating 
applications, maskant applications, sealing, adhesives, and cleaning 
operations are addressed. Emission limits for processes also addressed 
in the NESHAP are identical to the NESHAP limits. Those revisions to 
the NESHAP amendments described in this preamble and relevant to the 
CTG have been incorporated into the final CTG document. Many of the 
steps in aerospace manufacturing and rework operations involve the use 
of organic solvents and are sources of VOC emissions. The sources, 
mechanisms, and control of these VOC emissions are described in the 
CTG.
    The coating category VOC limits, application techniques, and 
equipment requirements identified as RACT in the CTG were assumed to 
represent RACT requirements 1 year after the major sources have met the 
NESHAP (MACT) requirements, and therefore, will be effective on 
September 1, 1999. (The NESHAP compliance date for existing sources is 
September 1, 1998). The EPA estimates that State and local regulations 
developed pursuant to this CTG will affect about 2,869 facilities. 
Since the only new requirements in the CTG (requirements that are not 
included in the NESHAP) concern sealants, adhesives, and specialty 
coatings, which represent only about 3 percent of all VOC emissions 
from aerospace operations, the additional costs and emission reductions 
resulting from the CTG will be negligible. Further information on costs 
is presented in the CTG document and in the July 1995 BID on the NESHAP 
for Aerospace Manufacturing and Rework Facilities.

IV. Administrative Requirements

A. Docket

    The docket is an organized and complete file of all of the 
information submitted to or otherwise considered by the EPA in the 
development of this rulemaking. The docket is a dynamic file, since 
material is added throughout the rulemaking development. The docketing 
system is intended to allow members of the public and the involved 
industries to readily identify and locate documents so that they can 
effectively participate in the rulemaking process. Along with the 
statement of basis and purpose of the proposed and promulgated 
standards and the EPA responses to significant comments, the content of 
the docket will serve as the record in case of judicial review (except 
for interagency review materials) (section 307(d)(7)(A) of the Act).

B. Paperwork Reduction Act

    The amendments do not impose any new information collection 
requirements and result in no change to the currently approved 
collection. The Office of Management and Budget (OMB) has approved the 
information collection requirements contained in the NESHAP for 
aerospace manufacturing and rework facilities under the provisions of 
the Paperwork Reduction Act, 44 U.S.C. 3501 et seq., and has assigned 
OMB control No. 2060-0314. (EPA ICR No. 1687.03). A copy of the 
Information Collection Request (ICR) may be obtained from Sandy Farmer, 
Regulatory Information Division; EPA; 401 M Street, S.W., (Mail Code 
2137); Washington, D.C. 20460 or by calling (202) 260-2740.
    Burden means the total time, effort, or financial resources 
expended by person to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data searches; complete and review the collection of 
information; and transmit or otherwise disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulation are listed in 40 CFR Part 9 and 48 CFR Chapter 15.
    Today's amendments should have no impact on the information 
collection burden estimates made previously. Today's action does not 
impose any additional information collection requirements. The reduced 
recordkeeping associated with cleaning solvents used for nonaerospace 
manufacturing/rework activities represents a 6 percent reduction in the 
burden estimated for the final rule. Consequently, the ICR has not been 
revised for purposes of today's action.

C. Executive Order 12866

    Under Executive Order (E.O.) 12866 (58 FR 51735 [October 4, 1993]), 
the EPA is required to determine whether a regulation is 
``significant'' and therefore subject to OMB review and the 
requirements of this E.O. to prepare a regulatory impact analysis 
(RIA). The E.O. defines ``significant regulatory action'' as one that 
is likely to result in a rule that may (1) have an annual effect on the 
economy of $100 million or more, or adversely affect in a material way 
the economy, a sector of the economy, productivity, competition, jobs, 
the environment, public health or safety, or State, local, or Tribal 
governments or communities; (2) create a serious inconsistency or 
otherwise interfere with an action taken or

[[Page 15016]]

planned by another agency; (3) materially alter the budgetary impact of 
entitlements, grants, user fees, or loan programs or the rights and 
obligations of recipients thereof; or (4) raise novel legal or policy 
issues arising out of legal mandates, the President's priorities, or 
the principles set forth in the E.O.
    Pursuant to the terms of Executive Order 12866, it has been 
determined that this action is not a ``significant regulatory action'' 
within the meaning of the E.O.
    Under E.O. 12866, the final CTG document for aerospace 
manufacturing and rework facilities is not considered a ``regulatory 
action,'' defined as ``any substantive action by an agency * * * that 
promulgates or is expected to lead to the promulgation of a final rule 
or regulation.'' This CTG document is not a regulatory action by EPA, 
rather it provides information to States to aid them in developing 
rules.

D. Regulatory Flexibility Act

    The EPA has determined that it is not necessary to prepare a 
regulatory flexibility analysis in connection with this final rule. The 
EPA has also determined that this rule will not have a significant 
impact on a substantial number of small entities. This final rule makes 
minor amendments to the Aerospace NESHAP, including changes to 
definitions, applicability provisions, and several minor changes to the 
standards (emission limits) and the monitoring, recordkeeping, and 
reporting requirements. In addition, this notice includes a standard 
for Type I chemical milling maskants and a test method for determining 
filtration efficiency of dry particulate filters. The overall impact of 
these amendments is a net decrease in requirements on all entities 
affected by this rule, including small entities. Therefore these 
amendments will not have a significant economic impact on a substantial 
number of small entities.

E. Submission to Congress

    Under 5 U.S.C. 801(a)(1)(A) as added by the Small Business 
Regulatory Enforcement Fairness Act of 1996, EPA submitted a report 
containing this rule and other required information to the U.S. Senate, 
the U.S. House of Representatives, and the Comptroller General of the 
General Accounting Office prior to publication of the rule in today's 
Federal Register. This rule is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

F. Unfunded Mandates Reform Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (``Unfunded 
Mandates Act'') (signed into law on March 22, 1995) requires that the 
Agency prepare a budgetary impact statement before promulgating a rule 
that includes a Federal mandate that may result in expenditure by 
State, local, and Tribal governments, in aggregate, or by the private 
sector, of $100 million or more in any 1 year. Section 203 requires the 
Agency to establish a plan for obtaining input from and informing, 
educating, and advising any small governments that may be significantly 
or uniquely affected by a proposed intergovernmental mandate. Section 
204 requires the Agency to develop a process to allow elected state, 
local, and Tribal government officials to provide input in the 
development of any proposal containing a significant Federal 
intergovernmental mandate.
    Under section 205 of the Unfunded Mandates Act, the Agency must 
identify and consider a reasonable number of regulatory alternatives 
before promulgating a rule for which a budgetary impact statement must 
be prepared. The Agency must select from those alternatives the least 
costly, most cost-effective, or least burdensome alternative that 
achieves the objectives of the rule, unless the Agency explains why 
this alternative is not selected or the selection of this alternative 
is inconsistent with law. The EPA has determined that these amendments 
do not include a Federal mandate that may result in expenditure by 
State, local, and Tribal governments, in aggregate, or by the private 
sector, of $100 million or more in any 1 year. Small governments will 
not be uniquely impacted by these amendments. Therefore, the 
requirements of the Unfunded Mandates Act do not apply to this action.

List of Subjects

40 CFR Part 9

    Environmental protection, Reporting and recordkeeping requirements.

40 CFR Part 63

    Environmental protection, Air pollution control, Hazardous 
substances, Reporting and recordkeeping requirements.

    Dated: March 10, 1998.
Carol M. Browner,
Administrator.
    For reasons set out in the preamble, parts 9 and 63 of title 40, 
chapter I, of the Code of Federal Regulations are amended as follows:

PART 9--[AMENDED]

    1. The authority citation for part 9 continues to read as follows:

    Authority: 7 U.S.C. 135 et seq., 136-136y; 15 U.S.C. 2001, 2003, 
2005, 2006, 2601-2671; 21 U.S.C. 331j, 346a, 348; 31 U.S.C. 9701; 33 
U.S.C. 1251 et seq., 1311, 1313d, 1314, 1318, 1321, 1326, 1330, 
1342, 1344, 1345 (d) and (e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 
1971-1975 Comp. p. 973; 42 U.S.C. 241, 242b, 243, 246, 300f, 300g, 
300g-1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-1, 300j-2, 
300j-3, 300j-4, 300j-9 1857 et seq., 6901-6992k, 7401-7671g, 7542, 
9601-9657, 11023, 11048.

    2. In Sec. 9.1 the table is amended by revising the entry ``63.752-
63.753'' to read as follows:


Sec. 9.1  OMB approvals under the Paperwork Reduction Act.

* * * * *

------------------------------------------------------------------------
                                                             OMB control
                      40 CFR citation                            No.    
------------------------------------------------------------------------
                                                                        
                         *    *    *    *    *                          
  National Emission Standards for Hazardous Air Pollutants for Source   
Categories                                                              
                                                                        
                          *    *    *    *    *                         
63.752-63.753..............................................    2060-0314
                                                                        
                          *    *    *    *    *                         
------------------------------------------------------------------------

PART 63--[AMENDED]

    3. The authority citation for part 63 continues to read as follows:

    Authority: 42 U.S.C. 7401 et seq.

Subpart GG--[Amended]

    4. Section 63.741 is amended by revising paragraph (b), paragraph 
(c) introductory text, paragraphs (c)(2), (c)(3), (c)(4), and the last 
three sentences of paragraph (f); and adding paragraphs (c)(7), (h), 
(i), and (j) to read as follows:


Sec. 63.741  Applicability and designation of affected sources.

* * * * *
    (b) The owner or operator of an affected source shall comply with 
the requirements of this subpart and of subpart A of this part, except 
as specified in Sec. 63.743(a) and Table 1 of this subpart.
    (c) Affected sources. The affected sources to which the provisions 
of this subpart apply are specified in paragraphs (c)(1) through (7) of 
this section. The activities subject to this subpart are limited to the 
manufacture or rework of aerospace vehicles or components as defined in 
this subpart. Where a dispute arises relating to the applicability of 
this subpart to a specific activity, the owner or operator shall 
demonstrate whether or not the activity is regulated under this 
subpart.
* * * * *

[[Page 15017]]

    (2) For organic HAP or VOC emissions, each primer application 
operation, which is the total of all primer applications at the 
facility.
    (3) For organic HAP or VOC emissions, each topcoat application 
operation, which is the total of all topcoat applications at the 
facility.
    (4) For organic HAP or VOC emissions, each depainting operation, 
which is the total of all depainting at the facility.
* * * * *
    (7) For inorganic HAP emissions, each spray booth or hangar that 
contains a primer or topcoat application operation subject to 
Sec. 63.745(g) or a depainting operation subject to Sec. 63.746(b)(4).
* * * * *
    (f) * * * These requirements also do not apply to parts and 
assemblies not critical to the vehicle's structural integrity or flight 
performance. The requirements of this subpart also do not apply to 
primers, topcoats, chemical milling maskants, strippers, and cleaning 
solvents containing HAP and VOC at concentrations less than 0.1 percent 
for carcinogens or 1.0 percent for noncarcinogens, as determined from 
manufacturer's representations. Additional specific exemptions from 
regulatory coverage are set forth in paragraphs (e), (g), (h), (i) and 
(j) of this section and Secs. 63.742, 63.744(a)(1), (b), (e), 
63.745(a), (f)(3), (g)(4), 63.746(a), (b)(5), 63.747(c)(3), and 
63.749(d).
* * * * *
    (h) Regulated activities associated with space vehicles designed to 
travel beyond the limit of the earth's atmosphere, including but not 
limited to satellites, space stations, and the Space Shuttle System 
(including orbiter, external tanks, and solid rocket boosters), are 
exempt from the requirements of this subpart, except for depainting 
operations found in Sec. 63.746.
    (i) Any waterborne coating for which the manufacturer's supplied 
data demonstrate that organic HAP and VOC contents are less than or 
equal to the organic HAP and VOC content limits for its coating type, 
as specified in Secs. 63.745(c) and 63.747(c), is exempt from the 
following requirements of this subpart: Secs. 63.745(d)-(e), 63.747(d)-
(e), 63.749(d) and (h), 63.750(c)-(h) and (k)-(m), 63.752(c) and (f), 
and 63.753(c) and (e). A facility shall maintain the manufacturer's 
supplied data and annual purchase records for each exempt waterborne 
coating readily available for inspection and review and shall retain 
these data for 5 years.
    (j) This subpart does not apply to rework operations performed on 
antique aerospace vehicles or components.
    5. Section 63.742 is amended by revising the definitions for 
``aircraft transparency,'' ``chemical milling maskant,'' ``chemical 
milling maskant application operation,'' ``cleaning solvent,'' 
``coating,'' ``high volume low pressure (HVLP) spray equipment,'' and 
``specialty coating''; by removing the parenthetical text from the end 
of the definition of ``Type II etchant''; by removing the last sentence 
from the definition of ``self-priming topcoat''; and by adding in 
alphabetical order definitions for ``antique aerospace vehicle or 
component,'' ``closed-cycle depainting system,'' ``recovery device,'' 
``Type I etchant,'' and ``waterborne (water-reducible) coating'' to 
read as follows:


Sec. 63.742  Definitions.

* * * * *
    Aircraft transparency means the aircraft windshield, canopy, 
passenger windows, lenses, and other components which are constructed 
of transparent materials.
    Antique aerospace vehicle or component means an aircraft or 
component thereof that was built at least 30 years ago. An antique 
aerospace vehicle would not routinely be in commercial or military 
service in the capacity for which it was designed.
* * * * *
    Chemical milling maskant means a coating that is applied directly 
to aluminum components to protect surface areas when chemical milling 
the component with a Type I or Type II etchant. Type I chemical milling 
maskants are used with a Type I etchant and Type II chemical milling 
maskants are used with a Type II etchant. This definition does not 
include bonding maskants, critical use and line sealer maskants, and 
seal coat maskants. Additionally, maskants that must be used with a 
combination of Type I or II etchants and any of the above types of 
maskants (i.e., bonding, critical use and line sealer, and seal coat) 
are also exempt from this subpart. (See also Type I and Type II etchant 
definitions.)
    Chemical milling maskant application operation means application of 
chemical milling maskant for use with Type I or Type II chemical 
milling etchants.
* * * * *
    Cleaning solvent means a liquid material used for hand-wipe, spray 
gun, or flush cleaning. This definition does not include solutions that 
contain HAP and VOC below the de minimis levels specified in 
Sec. 63.741(f).
    Closed-cycle depainting system means a dust-free, automated process 
that removes permanent coating in small sections at a time and 
maintains a continuous vacuum around the area(s) being depainted to 
capture emissions.
    Coating means a material that is applied to the surface of an 
aerospace vehicle or component to form a decorative, protective, or 
functional solid film, or the solid film itself.
* * * * *
    High volume low pressure (HVLP) spray equipment means spray 
equipment that is used to apply coating by means of a spray gun that 
operates at 10.0 psig of atomizing air pressure or less at the air cap.
* * * * *
    Recovery device means an individual unit of equipment capable of 
and normally used for the purpose of recovering chemicals for fuel 
value, use, or reuse. Examples of equipment that may be recovery 
devices include absorbers, carbon adsorbers, condensers, oil-water 
separators, or organic-water separators or organic removal devices such 
as decanters, strippers, or thin-film evaporation units.
* * * * *
    Specialty coating means a coating that, even though it meets the 
definition of a primer, topcoat, or self-priming topcoat, has 
additional performance criteria beyond those of primers, topcoats, and 
self-priming topcoats for specific applications. These performance 
criteria may include, but are not limited to, temperature or fire 
resistance, substrate compatibility, antireflection, temporary 
protection or marking, sealing, adhesively joining substrates, or 
enhanced corrosion protection. Individual specialty coatings are 
defined in appendix A to this subpart and in the CTG for Aerospace 
Manufacturing and Rework Operations (EPA 453/R-97-004).
* * * * *
    Type I etchant means a chemical milling etchant that contains 
varying amounts of dissolved sulfur and does not contain amines.
* * * * *
    Waterborne (water-reducible) coating means any coating that 
contains more than 5 percent water by weight as applied in its volatile 
fraction.
* * * * *
    6. Section 63.743 is amended by revising paragraphs (a) 
introductory text, (b) introductory text, and (c), and by adding 
paragraphs (a)(10) and (d) to read as follows:


Sec. 63.743  Standards: General.

    (a) Except as provided in paragraphs (a)(4) through (a)(10) of this 
section and in Table 1 of this subpart, each owner

[[Page 15018]]

or operator of an affected source subject to this subpart is also 
subject to the following sections of subpart A of this part:
* * * * *
    (10) For the purposes of compliance with the requirements of 
Sec. 63.5(b)(4) of the General Provisions and this subpart, owners or 
operators of existing primer or topcoat application operations and 
depainting operations who construct or reconstruct a spray booth or 
hangar that does not have the potential to emit 10 tons/yr or more of 
an individual inorganic HAP or 25 tons/yr or more of all inorganic HAP 
combined shall only be required to notify the Administrator of such 
construction or reconstruction on an annual basis. Notification shall 
be submitted on or before March 1 of each year and shall include the 
information required in Sec. 63.5(b)(4) for each such spray booth or 
hangar constructed or reconstructed during the prior calendar year, 
except that such information shall be limited to inorganic HAP's. No 
advance notification or written approval from the Administrator 
pursuant to Sec. 63.5(b)(3) shall be required for the construction or 
reconstruction of such a spray booth or hangar unless the booth or 
hangar has the potential to emit 10 tons/yr or more of an individual 
inorganic HAP or 25 tons/yr or more of all inorganic HAP combined.
    (b) Startup, shutdown, and malfunction plan. Each owner or operator 
that uses an air pollution control device or equipment to control HAP 
emissions shall prepare and operate in accordance with a startup, 
shutdown, and malfunction plan in accordance with Sec. 63.6. Dry 
particulate filter systems operated per the manufacturer's instructions 
are exempt from a startup, shutdown, and malfunction plan. A startup, 
shutdown, and malfunction plan shall be prepared for facilities using 
locally prepared operating procedures. In addition to the information 
required in Sec. 63.6, this plan shall also include the following 
provisions:
* * * * *
    (c) An owner or operator who uses an air pollution control device 
or equipment not listed in this subpart shall submit a description of 
the device or equipment, test data verifying the performance of the 
device or equipment in controlling organic HAP and/or VOC emissions, as 
appropriate, and specific operating parameters that will be monitored 
to establish compliance with the standards to the Administrator for 
approval not later than 120 days prior to the compliance date.
    (d) Instead of complying with the individual coating limits in 
Secs. 63.745 and 63.747, a facility may choose to comply with the 
averaging provisions specified in paragraphs (d)(1) through (d)(6) of 
this section.
    (1) Each owner or operator of a new or existing source shall use 
any combination of primers, topcoats (including self-priming topcoats), 
Type I chemical milling maskants, or Type II chemical milling maskants 
such that the monthly volume-weighted average organic HAP and VOC 
contents of the combination of primers, topcoats, Type I chemical 
milling maskants, or Type II chemical milling maskants, as determined 
in accordance with the applicable procedures set forth in Sec. 63.750, 
complies with the specified content limits in Secs. 63.745(c) and 
63.747(c), unless the permitting agency specifies a shorter averaging 
period as part of an ambient ozone control program.
    (2) Averaging is allowed only for uncontrolled primers, topcoats 
(including self-priming topcoats), Type I chemical milling maskants, or 
Type II chemical milling maskants.
    (3) Averaging is not allowed between primers and topcoats 
(including self-priming topcoats).
    (4) Averaging is not allowed between Type I and Type II chemical 
milling maskants.
    (5) Averaging is not allowed between primers and chemical milling 
maskants, or between topcoats and chemical milling maskants.
    (6) Each averaging scheme shall be approved in advance by the 
permitting agency and adopted as part of the facility's title V permit.
    7. Section 63.744 is amended by revising the text of paragraph (a) 
introductory text, and paragraphs (a)(1), (a)(2), (b) introductory 
text, (b)(1), (c)(1)(ii), (c)(2), (c)(4), (d), (e)(1), (e)(2), (e)(9), 
(e)(10), and (e)(11) and by removing the period at the end of paragraph 
(e)(12) and replacing it with ``; and''; by adding a sentence to (6) 
introductory text, and paragraph (e)(13); and by redesignating Table 3 
as Table 1 and revising it and transferring it from paragraph (a) to 
the end of this section as follows:


Sec. 63.744  Standards: Cleaning operations.

    (a) Housekeeping measures. Each owner or operator of a new or 
existing cleaning operation subject to this subpart shall comply with 
the requirements in these paragraphs unless the cleaning solvent used 
is identified in Table 1 of this section or contains HAP and VOC below 
the de minimis levels specified in Sec. 63.741(f).
    (1) Place cleaning solvent-laden cloth, paper, or any other 
absorbent applicators used for cleaning in bags or other closed 
containers upon completing their use. Ensure that these bags and 
containers are kept closed at all times except when depositing or 
removing these materials from the container. Use bags and containers of 
such design so as to contain the vapors of the cleaning solvent. 
Cotton-tipped swabs used for very small cleaning operations are exempt 
from this requirement.
    (2) Store fresh and spent cleaning solvents, except semi-aqueous 
solvent cleaners, used in aerospace cleaning operations in closed 
containers.
* * * * *
    (b) Hand-wipe cleaning. Each owner or operator of a new or existing 
hand-wipe cleaning operation (excluding cleaning of spray gun equipment 
performed in accordance with paragraph (c) of this section) subject to 
this subpart shall use cleaning solvents that meet one of the 
requirements specified in paragraphs (b)(1), (b)(2), and (b)(3) of this 
section. Cleaning solvent solutions that contain HAP and VOC below the 
de minimis levels specified in Sec. 63.741(f) are exempt from the 
requirements in paragraphs (b)(1), (b)(2), and (b)(3) of this section.
    (1) Meet one of the composition requirements in Table 1 of this 
section;
* * * * *
    (c) * * * Spray gun cleaning operations using cleaning solvent 
solutions that contain HAP and VOC below the de minimis levels 
specified in Sec. 63.741(f) are exempt from the requirements in 
paragraphs (c)(1) through (c)(4) of this section.
    (1) * * *
    (ii) If leaks are found during the monthly inspection required in 
Sec. 63.751(a), repairs shall be made as soon as practicable, but no 
later than 15 days after the leak was found. If the leak is not 
repaired by the 15th day after detection, the cleaning solvent shall be 
removed, and the enclosed cleaner shall be shut down until the leak is 
repaired or its use is permanently discontinued.
    (2) Nonatomized cleaning. Clean the spray gun by placing cleaning 
solvent in the pressure pot and forcing it through the gun with the 
atomizing cap in place. No atomizing air is to be used. Direct the 
cleaning solvent from the spray gun into a vat, drum, or other waste 
container that is closed when not in use.
* * * * *
    (4) Atomizing cleaning. Clean the spray gun by forcing the cleaning 
solvent through the gun and direct the resulting atomized spray into a 
waste

[[Page 15019]]

container that is fitted with a device designed to capture the atomized 
cleaning solvent emissions.
    (d) Flush cleaning. Each owner or operator of a flush cleaning 
operation subject to this subpart (excluding those in which Table 1 or 
semi-aqueous cleaning solvents are used) shall empty the used cleaning 
solvent each time aerospace parts or assemblies, or components of a 
coating unit (with the exception of spray guns) are flush cleaned into 
an enclosed container or collection system that is kept closed when not 
in use or into a system with equivalent emission control.
    (e) * * *
    (1) Cleaning during the manufacture, assembly, installation, 
maintenance, or testing of components of breathing oxygen systems that 
are exposed to the breathing oxygen;
    (2) Cleaning during the manufacture, assembly, installation, 
maintenance, or testing of parts, subassemblies, or assemblies that are 
exposed to strong oxidizers or reducers (e.g., nitrogen tetroxide, 
liquid oxygen, or hydrazine);
* * * * *
    (9) Cleaning of metallic and nonmetallic materials used in 
honeycomb cores during the manufacture or maintenance of these cores, 
and cleaning of the completed cores used in the manufacture of 
aerospace vehicles or components;
    (10) Cleaning of aircraft transparencies, polycarbonate, or glass 
substrates;
    (11) Cleaning and cleaning solvent usage associated with research 
and development, quality control, and laboratory testing;
* * * * *
    (13) Cleaning operations identified as essential uses under the 
Montreal Protocol for which the Administrator has allocated essential 
use allowances or exemptions in 40 CFR 82.4.

------------------------------------------------------------------------
    Cleaning solvent type               Composition requirements        
------------------------------------------------------------------------
Aqueous......................  Cleaning solvents in which water is the  
                                primary ingredient (80       
                                percent of cleaning solvent solution as 
                                applied must be water). Detergents,     
                                surfactants, and bioenzyme mixtures and 
                                nutrients may be combined with the water
                                along with a variety of additives, such 
                                as organic solvents (e.g., high boiling 
                                point alcohols), builders, saponifiers, 
                                inhibitors, emulsifiers, pH buffers, and
                                antifoaming agents. Aqueous solutions   
                                must have a flash point greater than 93 
                                deg.C (200  deg.F) (as reported by the  
                                manufacturer), and the solution must be 
                                miscible with water.                    
Hydrocarbon-based............  Cleaners that are composed of            
                                photochemically reactive hydrocarbons   
                                and oxygenated hydrocarbons and have a  
                                maximum vapor pressure of 7 mm Hg at 20 
                                deg.C (3.75 in. H2O at 68  deg.F). These
                                cleaners also contain no HAP.           
------------------------------------------------------------------------

    8. Section 63.745 is amended by revising paragraphs (e)(1), (e)(2), 
(f) introductory text, (f)(1) introductory text, the first sentence of 
(f)(2), (g)(2)(i), (g)(2)(ii), and (g)(2)(iii); removing paragraph 
(g)(2)(iv); redesignating paragraphs (g)(2)(v) and (g)(2)(vi) as 
(g)(2)(iv) and (g)(2)(v), respectively; revising the newly designated 
paragraphs (g)(2)(iv) and (g)(2)(v); removing the word ``and'' at the 
end of paragraph (g)(4)(viii); revising the punctuation ``.'' at the 
end of paragraph (g)(4)(ix) to read ``; and''; and adding paragraph 
(g)(4)(x) to read as follows:


Sec. 63.745  Standards: Primer and topcoat application operations.

* * * * *
    (e) * * *
    (1) Use primers and topcoats (including self-priming topcoats) with 
HAP and VOC content levels equal to or less than the limits specified 
in paragraphs (c)(1) through (c)(4) of this section; or
    (2) Use the averaging provisions described in Sec. 63.743(d).
    (f) Application equipment. Except as provided in paragraph (f)(3) 
of this section, each owner or operator of a new or existing primer or 
topcoat (including self-priming topcoat) application operation subject 
to this subpart in which any of the coatings contain organic HAP or VOC 
shall comply with the requirements specified in paragraphs (f)(1) and 
(f)(2) of this section.
    (1) All primers and topcoats (including self-priming topcoats) 
shall be applied using one or more of the application techniques 
specified in paragraphs (f)(1)(i) through (f)(1)(ix) of this section. * 
* *
* * * * *
    (2) All application devices used to apply primers or topcoats 
(including self-priming topcoats) shall be operated according to 
company procedures, local specified operating procedures, and/or the 
manufacturer's specifications, whichever is most stringent, at 
alltimes. * * *
* * * * *
    (g) * * *
    (2) * * *
    (i) For existing sources, the owner or operator must choose one of 
the following:
    (A) Before exhausting it to the atmosphere, pass the air stream 
through a dry particulate filter system certified using the methods 
described in Sec. 63.750(o) to meet or exceed the efficiency data 
points in Tables 1 and 2 of this section; or

    Table 1.--Two-Stage Arrestor; Liquid Phase Challenge for Existing   
                                 Sources                                
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>90........................................  >5.7                       
>50........................................  >4.1                       
>10........................................  >2.2                       
------------------------------------------------------------------------


Table 2.--Two-Stage Arrestor; Solid Phase Challenge for Existing Sources
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>90........................................  >8.1                       
>50........................................  >5.0                       
>10........................................  >2.6                       
------------------------------------------------------------------------

    (B) Before exhausting it to the atmosphere, pass the air stream 
through a waterwash system that shall remain in operation during all 
coating application operations; or
    (C) Before exhausting it to the atmosphere, pass the air stream 
through an air pollution control system that meets or exceeds the 
efficiency data points in Tables 1 and 2 of this section

[[Page 15020]]

and is approved by the permitting authority.
    (ii) For new sources, either:
    (A) Before exhausting it to the atmosphere, pass the air stream 
through a dry particulate filter system certified using the methods 
described in Sec. 63.750(o) to meet or exceed the efficiency data 
points in Tables 3 and 4 of this section; or

 Table 3.--Three-Stage Arrestor; Liquid Phase Challenge for New Sources 
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>95........................................  >2.0                       
>80........................................  >1.0                       
>65........................................  >0.42                      
------------------------------------------------------------------------


  Table 4.--Three-Stage Arrestor; Solid Phase Challenge for New Sources 
------------------------------------------------------------------------
                                              Aerodynamic particle size 
    Filtration efficiency requirement, %          range, m     
------------------------------------------------------------------------
>95........................................  >2.5                       
>85........................................  >1.1                       
>75........................................  >0.70                      
------------------------------------------------------------------------

    (B) Before exhausting it to the atmosphere, pass the air stream 
through an air pollution control system that meets or exceeds the 
efficiency data points in Tables 3 and 4 of this section and is 
approved by the permitting authority.
    (iii) Owners or operators of new sources that have commenced 
construction or reconstruction after June 6, 1994 but prior to October 
29, 1996 may comply with the following requirements in lieu of the 
requirements in paragraph (g)(2)(ii) of this section:
    (A) Pass the air stream through either a two-stage dry particulate 
filter system or a waterwash system before exhausting it to the 
atmosphere.
    (B) If the primer or topcoat contains chromium or cadmium, control 
shall consist of a HEPA filter system, three-stage filter system, or 
other control system equivalent to the three stage filter system as 
approved by the permitting agency.
    (iv) If a dry particulate filter system is used, the following 
requirements shall be met:
    (A) Maintain the system in good working order;
    (B) Install a differential pressure gauge across the filter banks;
    (C) Continuously monitor the pressure drop across the filter and 
read and record the pressure drop once per shift; and
    (D) Take corrective action when the pressure drop exceeds or falls 
below the filter manufacturer's recommended limit(s).
    (v) If a waterwash system is used, continuously monitor the water 
flow rate and read and record the water flow rate once per shift.
* * * * *
    (4) * * *
    (x) The use of hand-held spray can application methods.
    9. Section 63.746 is amended by revising the last sentence of 
paragraph (a) introductory text, (b)(1), (b)(3), (b)(4)(i), (b)(4)(ii), 
(b)(4)(iii)(C), (b)(4)(iv), the second sentence of paragraph (b)(4)(v), 
and (c)(1); and adding paragraphs (c)(2) and (c)(3) to read as follows:


Sec. 63.746  Standards: Depainting operations.

    (a) * * * This section does not apply to an aerospace manufacturing 
or rework facility that depaints six or less completed aerospace 
vehicles in a calendar year.
* * * * *
    (b)(1) HAP emissions--non-HAP chemical strippers and technologies. 
Except as provided in paragraphs (b)(2) and (b)(3) of this section, 
each owner or operator of a new or existing aerospace depainting 
operation subject to this subpart shall emit no organic HAP from 
chemical stripping formulations and agents or chemical paint softeners.
* * * * *
    (3) Each owner or operator of a new or existing depainting 
operation shall not, on an annual average basis, use more than 26 
gallons of organic HAP-containing chemical strippers or alternatively 
190 pounds of organic HAP per commercial aircraft depainted; or more 
than 50 gallons of organic HAP-containing chemical strippers or 
alternatively 365 pounds of organic HAP per military aircraft depainted 
for spot stripping and decal removal.
    (4) * * *
    (i) Perform the depainting operation in an enclosed area, unless a 
closed-cycle depainting system is used.
    (ii)(A) For existing sources pass any air stream removed from the 
enclosed area or closed-cycle depainting system through a dry 
particulate filter system, certified using the method described in 
Sec. 63.750(o) to meet or exceed the efficiency data points in Tables 1 
and 2 of Sec. 63.745, through a baghouse, or through a waterwash system 
before exhausting it to the atmosphere.
    (B) For new sources pass any air stream removed from the enclosed 
area or closed-cycle depainting system through a dry particulate filter 
system certified using the method described in Sec. 63.750(o) to meet 
or exceed the efficiency data points in Tables 3 and 4 of Sec. 63.745 
or through a baghouse before exhausting it to the atmosphere.
    (iii) * * *
    (C) Continuously monitor the pressure drop across the filter, and 
read and record the pressure drop once per shift; and
* * * * *
    (iv) If a waterwash system is used, continuously monitor the water 
flow rate, and read and record the water flow rate once per shift.
    (v) * * * If the water path in the waterwash system fails the 
visual continuity/flow characteristics check, as recorded pursuant to 
Sec. 63.752(e)(7), or the water flow rate, as recorded pursuant to 
Sec. 63.752(d)(2), exceeds the limit(s) specified by the booth 
manufacturer or in locally prepared operating procedures, or the booth 
manufacturer's or locally prepared maintenance procedures for the 
filter or waterwash system have not been performed as scheduled, shut 
down the operation immediately and take corrective action. * * *
* * * * *
    (c) * * *
    (1) All organic HAP emissions from the operation shall be reduced 
by the use of a control system. Each control system that was installed 
before the effective date shall reduce the operations' organic HAP 
emissions to the atmosphere by 81 percent or greater, taking into 
account capture and destruction or removal efficiencies.
    (2) Each control system installed on or after the effective date 
shall reduce organic HAP emissions to the atmosphere by 95 percent or 
greater. Reduction shall take into account capture and destruction or 
removal efficiencies, and may take into account the volume of chemical 
stripper used relative to baseline levels (e.g., the 95 percent 
efficiency may be achieved by controlling emissions at 81 percent 
efficiency with a control system and using 74 percent less stripper 
than in baseline applications). The baseline shall be calculated using 
data from 1996 and 1997, which shall be on a usage per aircraft or 
usage per square foot of surface basis.
    (3) The capture and destruction or removal efficiencies are to be

[[Page 15021]]

determined using the procedures in Sec. 63.750(g) when a carbon 
adsorber is used and those in Sec. 63.750(h) when a control device 
other than a carbon adsorber is used.
    10. Section 63.747 is amended by revising paragraphs (c)(1), (c)(2) 
and (e)(2) to read as follows:


Sec. 63.747  Standards: Chemical milling maskant application 
operations.

* * * * *
    (c) * * *
    (1) Organic HAP emissions from chemical milling maskants shall be 
limited to organic HAP content levels of no more than 622 grams of 
organic HAP per liter (5.2 lb/gal) of Type I chemical milling maskant 
(less water) as applied, and no more than 160 grams of organic HAP per 
liter (1.3 lb/gal) of Type II chemical milling maskant (less water) as 
applied.
    (2) VOC emissions from chemical milling maskants shall be limited 
to VOC content levels of no more than 622 grams of VOC per liter (5.2 
lb/gal) of Type I chemical milling maskant (less water and exempt 
solvents) as applied, and no more than 160 grams of VOC per liter (1.3 
lb/gal) of Type II chemical milling maskant (less water and exempt 
solvents) as applied.
* * * * *
    (e) * * *
    (2) Use the averaging provisions described in Sec. 63.743(d).
    11. Section 63.749 is amended by revising paragraphs (a), (b), 
(d)(3)(iii)(B), (d)(4)(iii), (f)(3)(ii)(A), and (h)(3)(i) to read as 
follows:


Sec. 63.749  Compliance dates and determinations.

    (a) Compliance dates. (1) Each owner or operator of an existing 
affected source subject to this subpart shall comply with the 
requirements of this subpart by September 1, 1998, except as specified 
in paragraph (a)(2) of this section. Owners or operators of new 
affected sources subject to this subpart shall comply on the effective 
date or upon startup, whichever is later. In addition, each owner or 
operator shall comply with the compliance dates specified in 
Sec. 63.6(b) and (c).
    (2) Owners or operators of existing primer or topcoat application 
operations and depainting operations who construct or reconstruct a 
spray booth or hangar must comply with the new source requirements for 
inorganic HAP specified in Secs. 63.745(g)(2)(ii) and 63.746(b)(4) for 
that new spray booth or hangar upon startup. Such sources must still 
comply with all other existing source requirements by September 1, 
1998.
    (b) General. Each facility subject to this subpart shall be 
considered in noncompliance if the owner or operator fails to submit a 
startup, shutdown, and malfunction plan as required by Sec. 63.743(b) 
or uses a control device other than one specified in this subpart that 
has not been approved by the Administrator, as required by 
Sec. 63.743(c).
* * * * *
    (d) * * *
    (3) * * *
    (iii) * * *
    (B) Uses an alternative application technique, as allowed under 
Sec. 63.745(f)(1)(ix), such that the emissions of both organic HAP and 
VOC for the implementation period of the alternative application method 
are less than or equal to the emissions generated using HVLP or 
electrostatic spray application methods as determined using the 
procedures specified in Sec. 63.750(i).
* * * * *
    (4) * * *
    (iii) * * *
    (A) Uses an application technique specified in Sec. 63.745 
(f)(1)(i) through (f)(1)(viii); or
    (B) Uses an alternative application technique, as allowed under 
Sec. 63.745(f)(1)(ix), such that the emissions of both organic HAP and 
VOC for the implementation period of the alternative application method 
are less than or equal to the emissions generated using HVLP or 
electrostatic spray application methods as determined using the 
procedures specified in Sec. 63.750(i).
* * * * *
    (f) * * *
    (3) * * *
    (ii) * * *
    (A) For any spot stripping and decal removal, the value of C, as 
determined using the procedures specified in Sec. 63.750(j), is less 
than or equal to 26 gallons of organic HAP-containing chemical stripper 
or 190 pounds of organic HAP per commercial aircraft depainted 
calculated on a yearly average; and is less than or equal to 50 gallons 
of organic HAP-containing chemical stripper or 365 pounds of organic 
HAP per military aircraft depainted calculated on a yearly average; and
* * * * *
    (h) * * *
    (3) * * *
    (i) For all uncontrolled chemical milling maskants, all values of 
Hi and Ha (as determined using the procedures 
specified in Sec. 63.750 (k) and (l)) are less than or equal to 622 
grams of organic HAP per liter (5.2 lb/gal) of Type I chemical milling 
maskant as applied (less water), and 160 grams of organic HAP per liter 
(1.3 lb/gal) of Type II chemical milling maskant as applied (less 
water). All values of Gi and Ga (as determined 
using the procedures specified in Sec. 63.750 (m) and (n)) are less 
than or equal to 622 grams of VOC per liter (5.2 lb/gal) of Type I 
chemical milling maskant as applied (less water and exempt solvents), 
and 160 grams of VOC per liter (1.3 lb/gal) of Type II chemical milling 
maskant (less water and exempt solvents) as applied.
* * * * *
    12. Section 63.750 is amended by revising the equation in paragraph 
(b)(2); paragraphs (c)(1), (e)(1), equation 7 (``Eq. 7'') in (e)(2), 
(g)(3)(ii), (g)(9)(i), (i)(1), (i)(2)(iii), (j) introductory text, 
(j)(1), (j)(3), (k) introductory text, (k)(1), (l)(4), and (n)(3); and 
by adding paragraphs (i)(2)(iv) and (o) to read as follows:


Sec. 63.750  Test methods and procedures.

* * * * *
    (b) * * *
    (2) * * *
    [GRAPHIC] [TIFF OMITTED] TR27MR98.001
    
* * * * *
    (c) * * *
    (1) For coatings that contain no exempt solvents, determine the 
total organic HAP content using manufacturer's supplied data or Method 
24 of 40 CFR part 60, appendix A, to determine the VOC content. The VOC 
content shall be used as a surrogate for total HAP content for coatings 
that contain no exempt solvent. If there is a discrepancy between the 
manufacturer's formulation data and the results of the Method 24 
analysis, compliance shall be based on the results from the Method 24 
analysis.
* * * * *
    (e) * * *
    (1) Determine the VOC content of each formulation (less water and 
exempt solvents) as applied using manufacturer's supplied data or 
Method 24 of 40 CFR part 60, appendix A, to determine the VOC content. 
The VOC content shall be used as a surrogate for total HAP content for 
coatings that contain no exempt solvent. If there is a discrepancy 
between the manufacturer's formulation data and the results of the 
Method 24 analysis, compliance shall be based on the results from the 
Method 24 analysis.

[[Page 15022]]

    (2) * * *
    [GRAPHIC] [TIFF OMITTED] TR27MR98.002
    
 * * * * *
    (g) * * *
    (3) * * *
    (ii) Assure that all HAP emissions from the affected HAP emission 
point(s) are segregated from gaseous emission points not affected by 
this subpart and that the emissions can be captured for measurement, as 
described in paragraphs (g)(2)(ii) (A) and (B) of this section;
* * * * *
    (9) * * *
    (i) When either EPA Method 18 or EPA Method 25A is to be used in 
the determination of the efficiency of a fixed-bed carbon adsorption 
system with a common exhaust stack for all the individual carbon 
adsorber vessels pursuant to paragraph (g) (2) or (4) of this section, 
the test shall consist of three separate runs, each coinciding with one 
or more complete sequences through the adsorption cycles of all of the 
individual carbon adsorber vessels.
* * * * *
    (i)(1) Alternative application method--primers and topcoats. Each 
owner or operator seeking to use an alternative application method (as 
allowed in Sec. 63.745(f)(1)(ix)) in complying with the standards for 
primers and topcoats shall use the procedures specified in paragraphs 
(i)(2)(i) and (i)(2)(ii) or (i)(2)(iii) of this section to determine 
the organic HAP and VOC emission levels of the alternative application 
technique as compared to either HVLP or electrostatic spray application 
methods.
    (2) * * *
    (iii) Test the proposed application method against either HVLP or 
electrostatic spray application methods in a laboratory or pilot 
production area, using parts and coatings representative of the 
process(es) where the alternative method is to be used. The laboratory 
test will use the same part configuration(s) and the same number of 
parts for both the proposed method and the HVLP or electrostatic spray 
application methods.
    (iv) Whenever the approach in either paragraph (i)(2)(ii) or 
(i)(2)(iii) of this section is used, the owner or operator shall 
calculate both the organic HAP and VOC emission reduction using 
equation:
[GRAPHIC] [TIFF OMITTED] TR27MR98.003

where:

P=organic HAP or VOC emission reduction, percent.
Eb=organic HAP or VOC emissions, in pounds, before the 
alternative application technique was implemented, as determined under 
paragraph (i)(2)(i) of this section.
Ea=organic HAP of VOC emissions, in pounds, after the 
alternative application technique was implemented, as determined under 
paragraph (i)(2)(ii) of this section.
* * * * *
    (j) Spot stripping and decal removal. Each owner or operator 
seeking to comply with Sec. 63.746(b)(3) shall determine the volume of 
organic HAP-containing chemical strippers or alternatively the weight 
of organic HAP used per aircraft using the procedure specified in 
paragraphs (j)(1) through (j)(3) of this section.
    (1) For each chemical stripper used for spot stripping and decal 
removal, determine for each annual period the total volume as applied 
or the total weight of organic HAP using the procedure specified in 
paragraph (d)(2) of this section.
* * * * *
    (3) Calculate the annual average volume of organic HAP-containing 
chemical stripper or weight of organic HAP used for spot stripping and 
decal removal per aircraft using equation 20 (volume) or equation 21 
(weight):
[GRAPHIC] [TIFF OMITTED] TR27MR98.004

where:

C=annual average volume (gal per aircraft) of organic HAP-containing 
chemical stripper used for spot stripping and decal removal.
n=number of organic HAP-containing chemical strippers used in the 
annual period.
Vsi=volume (gal) of organic HAP-containing chemical stripper 
(i) used during the annual period.
A=number of aircraft for which depainting operations began during the 
annual period.
[GRAPHIC] [TIFF OMITTED] TR27MR98.005

where:

C = annual average weight (lb per aircraft) of organic HAP (chemical 
stripper) used for spot stripping and decal removal.
m = number of organic HAP contained in each chemical stripper, as 
applied.
n = number of organic HAP-containing chemical strippers used in the 
annual period.
Whi = weight fraction (expressed as a decimal) of each 
organic HAP (i) contained in the chemical stripper, as applied, for 
each aircraft depainted.
Dhi = density (lb/gal) of each organic HAP-containing 
chemical stripper (i), used in the annual period.
Vsi = volume (gal) of organic HAP-containing chemical 
stripper (i) used during the annual period.
A = number of aircraft for which depainting operations began during the 
annual period.

    (k) Organic HAP content level determination--compliant chemical 
milling maskants. For those uncontrolled chemical milling maskants 
complying with the chemical milling maskant organic HAP content limit 
specified in Sec. 63.747(c)(1) without being averaged, the following 
procedures shall be used to determine the mass of organic HAP emitted 
per unit volume of coating (chemical milling maskant) i as applied 
(less water), Hi (lb/gal).
    (1) For coatings that contain no exempt solvents, determine the 
total organic HAP content using manufacturer's supplied data or Method 
24 of 40 CFR part 60, appendix A to determine the VOC content. The VOC 
content shall be used as a surrogate for total HAP content for coatings 
that contain no exempt solvent. If there is a discrepancy between the 
manufacturer's formulation data and the results of the Method 24 
analysis, compliance shall be based on the results from the Method 24 
analysis.
* * * * *
    (l) * * *
    (4) Calculate the volume-weighted average mass of organic HAP 
emitted per unit volume (lb/gal) of chemical milling maskant (less 
water) as applied for all chemical milling maskants during each 30-day 
period using equation 22:
[GRAPHIC] [TIFF OMITTED] TR27MR98.006

* * * * *
    (n) * * *
    (3) Calculate the volume-weighted average mass of VOC emitted per 
unit volume (lb/gal) of chemical milling maskant (less water and exempt 
solvents) as applied during each 30-day period using equation 23:

[[Page 15023]]

[GRAPHIC] [TIFF OMITTED] TR27MR98.007


* * * * *
    (o) Inorganic HAP emissions--dry particulate filter certification 
requirements. Dry particulate filters used to comply with 
Sec. 63.745(g)(2) or Sec. 63.746(b)(4) must be certified by the filter 
manufacturer or distributor, paint/depainting booth supplier, and/or 
the facility owner or operator using method 319 in appendix A of 
subpart A of this part, to meet or exceed the efficiency data points 
found in Tables 1 and 2, or 3 and 4 of Sec. 63.745 for existing or new 
sources respectively.
    13. Section 63.751 is amended by revising the first sentence of 
paragraph (b)(6)(ii)(A), (b)(6)(iii) introductory text, and the first 
sentence of paragraph (b)(6)(iii)(A)(2) introductory text and 
paragraphs (b)(6)(iii)(D), (c)(1), (c)(2) and (d) to read as follows:


Sec. 63.751  Monitoring requirements.

* * * * *
    (b) * * *
    (6) * * *
    (ii) * * *
    (A) Except as allowed by paragraph (b)(6)(iii)(A)(2) of this 
section, all continuous emission monitors shall comply with performance 
specification (PS) 8 or 9 in 40 CFR part 60, appendix B, as appropriate 
depending on whether VOC or HAP concentration is being measured. * * *
* * * * *
    (iii) Owners or operators complying with Sec. 63.745(d), 
Sec. 63.746(c), or Sec. 63.747(d) through the use of a control device 
and establishing a site-specific operating parameter in accordance with 
paragraph (b)(1) of this section shall fulfill the requirements of 
paragraph (b)(6)(iii)(A) of this section and paragraph (b)(6)(iii)(B) 
or (C) of this section, as appropriate.
    (A) * * *
    (2) For owners or operators using a nonregenerative carbon 
adsorber, in lieu of using continuous emission monitors as specified in 
paragraph (b)(6)(iii)(A)(1) of this section, the owner or operator may 
use a portable monitoring device to monitor total HAP or VOC 
concentration at the inlet and outlet or the outlet of the carbon 
adsorber as appropriate. * * *
* * * * *
    (D) If complying with Sec. 63.745(d), Sec. 63.746(c), or 
Sec. 63.747(d) through the use of a nonregenerative carbon adsorber, in 
lieu of the requirements of paragraph (b)(6)(iii)(B) or (C) of this 
section, the owner or operator may replace the carbon in the carbon 
adsorber system with fresh carbon at a regular predetermined time 
interval as determined in accordance with paragraph (b)(2) of this 
section.
* * * * *
    (c) * * *
    (1) Each owner or operator using a dry particulate filter system to 
meet the requirements of Sec. 63.745(g)(2) shall, while primer or 
topcoat application operations are occurring, continuously monitor the 
pressure drop across the system and read and record the pressure drop 
once per shift following the recordkeeping requirements of 
Sec. 63.752(d).
    (2) Each owner or operator using a waterwash system to meet the 
requirements of Sec. 63.745(g)(2) shall, while primer or topcoat 
application operations are occurring, continuously monitor the water 
flow rate through the system, and read and record the water flow rate 
once per shift following the recordkeeping requirements of 
Sec. 63.752(d).
    (d) Particulate filters and waterwash booths--depainting 
operations. Each owner or operator using a dry particulate filter or 
waterwash system in accordance with the requirements of 
Sec. 63.746(b)(4) shall, while depainting operations are occurring, 
continuously monitor the pressure drop across the particulate filters 
or the water flow rate through the waterwash system and read and record 
the pressure drop or the water flow rate once per shift following the 
recordkeeping requirements of Sec. 63.752(e).
* * * * *
    14. Section 63.752 is amended by revising paragraphs (b)(1), 
(e)(1)(ii), (e)(6), and (f) introductory text; and by removing 
paragraph (d)(4) to read as follows:


Sec. 63.752  Recordkeeping requirements.

* * * * *
    (b) * * *
    (1) The name, vapor pressure, and documentation showing the organic 
HAP constituents of each cleaning solvent used for affected cleaning 
operations at the facility.
* * * * *
    (e) * * *
    (1) * * *
    (ii) Monthly volumes of each organic HAP containing chemical 
stripper used or monthly weight of organic HAP-material used for spot 
stripping and decal removal.
* * * * *
    (6) Spot stripping and decal removal. For spot stripping and decal 
removal, the volume of organic HAP-containing chemical stripper or 
weight of organic HAP used, the annual average volume of organic HAP-
containing chemical stripper or weight of organic HAP used per 
aircraft, the annual number of aircraft stripped, and all data and 
calculations used.
* * * * *
    (f) Chemical milling maskant application operations. Each owner or 
operator seeking to comply with the organic HAP and VOC content limits 
for the chemical milling maskant application operation, as specified in 
Sec. 63.747(c), or the control system requirements specified in 
Sec. 63.747(d), shall record the information specified in paragraphs 
(f)(1) through (f)(4) of this section, as appropriate.
* * * * *
    15. Section 63.753 is amended by revising paragraphs (a)(1) 
introductory text and (d)(2)(i) to read as follows:


Sec. 63.753  Reporting requirements.

    (a)(1) Except as provided in paragraphs (a)(2) and (a)(3) of this 
section, each owner or operator subject to this subpart shall fulfill 
the requirements contained in Sec. 63.9(a) through (e) and (h) through 
(j), Notification requirements, and Sec. 63.10(a), (b), (d), and (f), 
Recordkeeping and reporting requirements, of the General Provisions, 40 
CFR part 63, subpart A, and that the initial notification for existing 
sources required in Sec. 63.9(b)(2) shall be submitted not later than 
September 1, 1997. In addition to the requirements of Sec. 63.9(h), the 
notification of compliance status shall include:
* * * * *
    (d) * * *
    (2) * * *
    (i) The average volume per aircraft of organic HAP-containing 
chemical strippers or weight of organic HAP used for spot stripping and 
decal removal operations if it exceeds the limits specified in 
Sec. 63.746(b)(3); and
* * * * *
    16. Table 1 is added to the end of subpart GG to read as follows:

[[Page 15024]]



                Table 1 to Subpart GG of Part 63--General Provisions Applicability to Subpart GG                
----------------------------------------------------------------------------------------------------------------
              Reference                 Applies to affected sources in subpart GG             Comment           
----------------------------------------------------------------------------------------------------------------
63.1(a)(1)...........................  Yes                                                                      
63.1(a)(2)...........................  Yes                                                                      
63.1(a)(3)...........................  Yes                                                                      
63.1(a)(4)...........................  Yes                                                                      
63.1(a)(5)...........................  No........................................  Reserved.                    
63.1(a)(6)...........................  Yes                                                                      
63.1(a)(7)...........................  Yes                                                                      
63.1(a)(8)...........................  Yes                                                                      
63.1(a)(9)...........................  No........................................  Reserved.                    
63.1(a)(10)..........................  Yes                                                                      
63.1(a)(11)..........................  Yes                                                                      
63.1(a)(12)..........................  Yes                                                                      
63.1(a)(13)..........................  Yes                                                                      
63.1(a)(14)..........................  Yes                                                                      
63.1(b)(1)...........................  Yes                                                                      
63.1(b)(2)...........................  Yes                                                                      
63.1(b)(3)...........................  Yes                                                                      
63.1(c)(1)...........................  Yes                                                                      
63.1(c)(2)...........................  Yes.......................................  Subpart GG does not apply to 
                                                                                    area sources.               
63.1(c)(3)...........................  No........................................  Reserved.                    
63.1(c)(4)...........................  Yes                                                                      
63.1(c)(5)...........................  Yes                                                                      
63.1(d)..............................  No........................................  Reserved.                    
63.1(e)..............................  Yes                                                                      
63.2.................................  Yes                                                                      
63.3.................................  Yes                                                                      
63.4(a)(1)...........................  Yes                                                                      
63.4(a)(2)...........................  Yes                                                                      
63.4(a)(3)...........................  Yes                                                                      
63.4(a)(4)...........................  No........................................  Reserved.                    
63.4(a)(5)...........................  Yes                                                                      
63.4(b)..............................  Yes                                                                      
63.4(c)..............................  Yes                                                                      
63.5(a)..............................  Yes                                                                      
63.5(b)(1)...........................  Yes                                                                      
63.5(b)(2)...........................  No........................................  Reserved.                    
63.5(b)(3)...........................  Yes                                                                      
63.5(b)(4)...........................  Yes                                                                      
63.5(b)(5)...........................  Yes                                                                      
63.5(b)(6)...........................  Yes                                                                      
63.5(c)..............................  No........................................  Reserved.                    
63.5(d)(1)(i)........................  Yes                                                                      
63.5(d)(1)(ii)(A)-(H)................  Yes                                                                      
63.5(d)(1)(ii)(I)....................  No........................................  Reserved.                    
63.5(d)(1)(ii)(J)....................  Yes                                                                      
63.5(d)(1)(iii)......................  Yes                                                                      
63.5(d)(2)-(4).......................  Yes                                                                      
63.5(e)..............................  Yes                                                                      
63.5(f)..............................  Yes                                                                      
63.6(a)..............................  Yes                                                                      
63.6(b)(1)-(5).......................  Yes.......................................  Sec.  63.749(a) specifies    
                                                                                    compliance dates for new    
                                                                                    sources.                    
63.6(b)(6)...........................  No........................................  Reserved.                    
63.6(b)(7)...........................  Yes                                                                      
63.6(c)(1)...........................  Yes                                                                      
63.6(c)(2)...........................  No........................................  The standards in subpart GG  
                                                                                    are promulgated under       
                                                                                    section 112(d) of the Act.  
63.6(c)(3)-(4).......................  No........................................  Reserved.                    
63.6(c)(5)...........................  Yes                                                                      
63.6(d)..............................  No........................................  Reserved.                    
63.6(e)..............................  Yes.......................................  63.743(b) includes additional
                                                                                    provisions for the operation
                                                                                    and maintenance plan.       
63.6(f)..............................  Yes                                                                      
63.6(g)..............................  Yes                                                                      
63.6(h)..............................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.6(i)(1)-(3).......................  Yes                                                                      
63.6(i)(4)(i)(A).....................  Yes                                                                      
63.6(i)(4)(i)(B).....................  No........................................  Sec.  63.743(a)(4) specifies 
                                                                                    that requests for extension 
                                                                                    of compliance must be       
                                                                                    submitted no later than 120 
                                                                                    days before an affected     
                                                                                    source's compliance date.   
63.6(i)(4)(ii).......................  No........................................  The standards in subpart GG  
                                                                                    are promulgated under       
                                                                                    section 112(d) of the Act.  

[[Page 15025]]

                                                                                                                
63.6(i)(5)-(12)......................  Yes                                                                      
63.6(i)(13)..........................  Yes                                                                      
63.6(i)(14)..........................  Yes                                                                      
63.6(i)(15)..........................  No........................................  Reserved.                    
63.6(i)(16)..........................  Yes                                                                      
63.6(j)..............................  Yes                                                                      
63.7(a)(1)...........................  Yes                                                                      
63.7(a)(2)(i)-(vi)...................  Yes                                                                      
63.7(a)(2)(vii)-(viii)...............  No........................................  Reserved.                    
63.7(a)(2)(ix).......................  Yes                                                                      
63.7(a)(3)...........................  Yes                                                                      
63.7(b)..............................  Yes                                                                      
63.7(c)..............................  Yes                                                                      
63.7(d)..............................  Yes                                                                      
63.7(e)..............................  Yes                                                                      
63.7(f)..............................  Yes                                                                      
63.7(g)(1)...........................  Yes                                                                      
63.7(g)(2)...........................  No........................................  Reserved.                    
63.7(g)(3)...........................  Yes                                                                      
63.7(h)..............................  Yes                                                                      
63.8(a)(1)-(2).......................  Yes                                                                      
63.8(a)(3)...........................  No........................................  Reserved.                    
63.8(a)(4)...........................  Yes                                                                      
63.8(b)..............................  Yes                                                                      
63.8(c)..............................  Yes                                                                      
63.8(d)..............................  No                                                                       
63.8(e)(1)-(4).......................  Yes                                                                      
63.8(e)(5)(i)........................  Yes                                                                      
63.8(e)(5)(ii).......................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.8(f)(1)...........................  Yes                                                                      
63.8(f)(2)(i)-(vii)..................  Yes                                                                      
63.8(f)(2)(viii).....................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.8(f)(2)(ix).......................  Yes                                                                      
63.8(f)(3)-(6).......................  Yes                                                                      
63.8(g)..............................  Yes                                                                      
63.9(a)..............................  Yes                                                                      
63.9(b)(1)...........................  Yes                                                                      
63.9(b)(2)...........................  Yes.......................................  Sec.  63.753(a)(1) requires  
                                                                                    submittal of the initial    
                                                                                    notification at least 1 year
                                                                                    prior to the compliance     
                                                                                    date; Sec.  63.753(a)(2)    
                                                                                    allows a title V or part 70 
                                                                                    permit application to be    
                                                                                    substituted for the initial 
                                                                                    notification in certain     
                                                                                    circumstances.              
63.9(b)(3)...........................  Yes                                                                      
63.9(b)(4)...........................  Yes                                                                      
63.9(b)(5)...........................  Yes                                                                      
63.9(c)..............................  Yes                                                                      
63.9(d)..............................  Yes                                                                      
63.9(e)..............................  Yes                                                                      
63.9(f)..............................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.9(g)(1)...........................  No                                                                       
63.9(g)(2)...........................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.9(g)(3)...........................  No                                                                       
63.9(h)(1)-(3).......................  Yes.......................................  Sec.  63.753(a)(1) also      
                                                                                    specifies additional        
                                                                                    information to be included  
                                                                                    in the notification of      
                                                                                    compliance status.          
63.9(h)(4)...........................  No........................................  Reserved.                    
63.9(h)(5)-(6).......................  Yes                                                                      
63.9(i)..............................  Yes                                                                      
63.9(j)..............................  Yes                                                                      
63.10(a).............................  Yes                                                                      
63.10(b).............................  Yes                                                                      
63.10(c)(1)..........................  No                                                                       
63.10(c)(2)-(4)......................  No........................................  Reserved.                    
63.10(c)(5)-(8)......................  No                                                                       
63.10(c)(9)..........................  No........................................  Reserved.                    
63.10(c)(10)-(13)....................  No                                                                       
63.10(c)(14).........................  No........................................  Sec.  63.8(d) does not apply 
                                                                                    to this subpart.            
63.10(c)(15).........................  No                                                                       

[[Page 15026]]

                                                                                                                
63.10(d)(1)-(2)......................  Yes                                                                      
63.10(d)(3)..........................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.10(d)(4)..........................  Yes                                                                      
63.10(d)(5)..........................  Yes                                                                      
63.(10)(e)(1)........................  No                                                                       
63.10(e)(2)(i).......................  No                                                                       
63.10(e)(2)(ii)......................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.10(e)(3)..........................  No                                                                       
63.10(e)(4)..........................  No........................................  The standards in subpart GG  
                                                                                    do not include opacity      
                                                                                    standards.                  
63.10(f).............................  Yes                                                                      
63.11................................  Yes                                                                      
63.12................................  Yes                                                                      
63.13................................  Yes                                                                      
63.14................................  Yes                                                                      
63.15................................  Yes                                                                      
----------------------------------------------------------------------------------------------------------------

    17. Appendix A of subpart GG is added to read as follows:

Appendix A to Subpart GG of Part 63--Specialty Coating Definitions

    Ablative coating--A coating that chars when exposed to open 
flame or extreme temperatures, as would occur during the failure of 
an engine casing or during aerodynamic heating. The ablative char 
surface serves as an insulative barrier, protecting adjacent 
components from the heat or open flame.
    Adhesion promoter--A very thin coating applied to a substrate to 
promote wetting and form a chemical bond with the subsequently 
applied material.
    Adhesive bonding primer--A primer applied in a thin film to 
aerospace components for the purpose of corrosion inhibition and 
increased adhesive bond strength by attachment. There are two 
categories of adhesive bonding primers: primers with a design cure 
at 250 deg.F or below and primers with a design cure above 
250 deg.F.
    Aerosol coating--A hand-held, pressurized, nonrefillable 
container that expels an adhesive or a coating in a finely divided 
spray when a valve on the container is depressed.
    Antichafe coating--A coating applied to areas of moving 
aerospace components that may rub during normal operations or 
installation.
    Bearing coating--A coating applied to an antifriction bearing, a 
bearing housing, or the area adjacent to such a bearing in order to 
facilitate bearing function or to protect base material from 
excessive wear. A material shall not be classified as a bearing 
coating if it can also be classified as a dry lubricative material 
or a solid film lubricant.
    Bonding maskant--A temporary coating used to protect selected 
areas of aerospace parts from strong acid or alkaline solutions 
during processing for bonding.
    Caulking and smoothing compounds--Semi-solid materials which are 
applied by hand application methods and are used to aerodynamically 
smooth exterior vehicle surfaces or fill cavities such as bolt hole 
accesses. A material shall not be classified as a caulking and 
smoothing compound if it can also be classified as a sealant.
    Chemical agent-resistant coating (CARC)--An exterior topcoat 
designed to withstand exposure to chemical warfare agents or the 
decontaminants used on these agents.
    Clear coating--A transparent coating usually applied over a 
colored opaque coating, metallic substrate, or placard to give 
improved gloss and protection to the color coat. In some cases, a 
clearcoat refers to any transparent coating without regard to 
substrate.
    Commercial exterior aerodynamic structure primer--A primer used 
on aerodynamic components and structures that protrude from the 
fuselage, such as wings and attached components, control surfaces, 
horizontal stabilizers, vertical fins, wing-to-body fairings, 
antennae, and landing gear and doors, for the purpose of extended 
corrosion protection and enhanced adhesion.
    Commercial interior adhesive--Materials used in the bonding of 
passenger cabin interior components. These components must meet the 
FAA fireworthiness requirements.
    Compatible substrate primer--Includes two categories: compatible 
epoxy primer and adhesive primer. Compatible epoxy primer is primer 
that is compatible with the filled elastomeric coating and is epoxy 
based. The compatible substrate primer is an epoxy-polyamide primer 
used to promote adhesion of elastomeric coatings such as impact-
resistant coatings. Adhesive primer is a coating that (1) inhibits 
corrosion and serves as a primer applied to bare metal surfaces or 
prior to adhesive application, or (2) is applied to surfaces that 
can be expected to contain fuel. Fuel tank coatings are excluded 
from this category.
    Corrosion prevention system--A coating system that provides 
corrosion protection by displacing water and penetrating mating 
surfaces, forming a protective barrier between the metal surface and 
moisture. Coatings containing oils or waxes are excluded from this 
category.
    Critical use and line sealer maskant--A temporary coating, not 
covered under other maskant categories, used to protect selected 
areas of aerospace parts from strong acid or alkaline solutions such 
as those used in anodizing, plating, chemical milling and processing 
of magnesium, titanium, high-strength steel, high-precision aluminum 
chemical milling of deep cuts, and aluminum chemical milling of 
complex shapes. Materials used for repairs or to bridge gaps left by 
scribing operations (i.e. line sealer) are also included in this 
category.
    Cryogenic flexible primer--A primer designed to provide 
corrosion resistance, flexibility, and adhesion of subsequent 
coating systems when exposed to loads up to and surpassing the yield 
point of the substrate at cryogenic temperatures (-275 deg.F and 
below).
    Cryoprotective coating--A coating that insulates cryogenic or 
subcooled surfaces to limit propellant boil-off, maintain structural 
integrity of metallic structures during ascent or re-entry, and 
prevent ice formation.
    Cyanoacrylate adhesive--A fast-setting, single component 
adhesive that cures at room temperature. Also known as ``super 
glue.''
    Dry lubricative material--A coating consisting of lauric acid, 
cetyl alcohol, waxes, or other non-cross linked or resin-bound 
materials which act as a dry lubricant.
    Electric or radiation-effect coating--A coating or coating 
system engineered to interact, through absorption or reflection, 
with specific regions of the electromagnetic energy spectrum, such 
as the ultraviolet, visible, infrared, or microwave regions. Uses 
include, but are not limited to, lightning strike protection, 
electromagnetic pulse (EMP) protection, and radar avoidance. 
Coatings that have been designated as ``classified'' by the 
Department of Defense are exempt.
    Electrostatic discharge and electromagnetic interference (EMI) 
coating--A coating applied to space vehicles, missiles, aircraft 
radomes, and helicopter blades to disperse static energy or reduce 
electromagnetic interference.

[[Page 15027]]

    Elevated-temperature Skydrol-resistant commercial primer--A 
primer applied primarily to commercial aircraft (or commercial 
aircraft adapted for military use) that must withstand immersion in 
phosphate-ester (PE) hydraulic fluid (Skydrol 500b or equivalent) at 
the elevated temperature of 150 deg.F for 1,000 hours.
    Epoxy polyamide topcoat--A coating used where harder films are 
required or in some areas where engraving is accomplished in 
camouflage colors.
    Fire-resistant (interior) coating--For civilian aircraft, fire-
resistant interior coatings are used on passenger cabin interior 
parts that are subject to the FAA fireworthiness requirements. For 
military aircraft, fire-resistant interior coatings are used on 
parts subject to the flammability requirements of MIL-STD-1630A and 
MIL-A-87721. For space applications, these coatings are used on 
parts subject to the flammability requirements of SE-R-0006 and SSP 
30233.
    Flexible primer--A primer that meets flexibility requirements 
such as those needed for adhesive bond primed fastener heads or on 
surfaces expected to contain fuel. The flexible coating is required 
because it provides a compatible, flexible substrate over bonded 
sheet rubber and rubber-type coatings as well as a flexible bridge 
between the fasteners, skin, and skin-to-skin joints on outer 
aircraft skins. This flexible bridge allows more topcoat flexibility 
around fasteners and decreases the chance of the topcoat cracking 
around the fasteners. The result is better corrosion resistance.
    Flight test coating--A coating applied to aircraft other than 
missiles or single-use aircraft prior to flight testing to protect 
the aircraft from corrosion and to provide required marking during 
flight test evaluation.
    Fuel tank adhesive--An adhesive used to bond components exposed 
to fuel and that must be compatible with fuel tank coatings.
    Fuel tank coating--A coating applied to fuel tank components to 
inhibit corrosion and/or bacterial growth and to assure sealant 
adhesion in extreme environmental conditions.
    High temperature coating--A coating designed to withstand 
temperatures of more than 350  deg.F.
    Insulation covering--Material that is applied to foam insulation 
to protect the insulation from mechanical or environmental damage.
    Intermediate release coating--A thin coating applied beneath 
topcoats to assist in removing the topcoat in depainting operations 
and generally to allow the use of less hazardous depainting methods.
    Lacquer--A clear or pigmented coating formulated with a 
nitrocellulose or synthetic resin to dry by evaporation without a 
chemical reaction. Lacquers are resoluble in their original solvent.
    Metalized epoxy coating--A coating that contains relatively 
large quantities of metallic pigmentation for appearance and/or 
added protection.
    Mold release--A coating applied to a mold surface to prevent the 
molded piece from sticking to the mold as it is removed.
    Nonstructural adhesive--An adhesive that bonds nonload bearing 
aerospace components in noncritical applications and is not covered 
in any other specialty adhesive categories.
    Optical anti-reflection coating--A coating with a low 
reflectance in the infrared and visible wavelength ranges, which is 
used for anti-reflection on or near optical and laser hardware.
    Part marking coating--Coatings or inks used to make identifying 
markings on materials, components, and/or assemblies. These markings 
may be either permanent or temporary.
    Pretreatment coating--An organic coating that contains at least 
0.5 percent acids by weight and is applied directly to metal or 
composite surfaces to provide surface etching, corrosion resistance, 
adhesion, and ease of stripping.
    Rain erosion-resistant coating--A coating or coating system used 
to protect the leading edges of parts such as flaps, stabilizers, 
radomes, engine inlet nacelles, etc. against erosion caused by rain 
impact during flight.
    Rocket motor bonding adhesive--An adhesive used in rocket motor 
bonding applications.
    Rocket motor nozzle coating--A catalyzed epoxy coating system 
used in elevated temperature applications on rocket motor nozzles.
    Rubber-based adhesive--Quick setting contact cements that 
provide a strong, yet flexible, bond between two mating surfaces 
that may be of dissimilar materials.
    Scale inhibitor--A coating that is applied to the surface of a 
part prior to thermal processing to inhibit the formation of scale.
    Screen print ink--Inks used in screen printing processes during 
fabrication of decorative laminates and decals.
    Seal coat maskant--An overcoat applied over a maskant to improve 
abrasion and chemical resistance during production operations.
    Sealant--A material used to prevent the intrusion of water, 
fuel, air, or other liquids or solids from certain areas of 
aerospace vehicles or components. There are two categories of 
sealants: extrudable/rollable/brushable sealants and sprayable 
sealants.
    Silicone insulation material--Insulating material applied to 
exterior metal surfaces for protection from high temperatures caused 
by atmospheric friction or engine exhaust. These materials differ 
from ablative coatings in that they are not ``sacrificial.''
    Solid film lubricant--A very thin coating consisting of a binder 
system containing as its chief pigment material one or more of the 
following: molybdenum, graphite, polytetrafluoroethylene (PTFE), or 
other solids that act as a dry lubricant between faying surfaces.
    Specialized function coatings--Coatings that fulfill extremely 
specific engineering requirements that are limited in application 
and are characterized by low volume usage. This category excludes 
coatings covered in other Specialty Coating categories.
    Structural autoclavable adhesive--An adhesive used to bond load-
carrying aerospace components that is cured by heat and pressure in 
an autoclave.
    Structural nonautoclavable adhesive--An adhesive cured under 
ambient conditions that is used to bond load-carrying aerospace 
components or for other critical functions, such as nonstructural 
bonding in the proximity of engines.
    Temporary protective coating--A coating applied to provide 
scratch or corrosion protection during manufacturing, storage, or 
transportation. Two types include peelable protective coatings and 
alkaline removable coatings. These materials are not intended to 
protect against strong acid or alkaline solutions. Coatings that 
provide this type of protection from chemical processing are not 
included in this category.
    Thermal control coating--Coatings formulated with specific 
thermal conductive or radiative properties to permit temperature 
control of the substrate.
    Touch-up and Repair Coating--A coating used to cover minor 
coating imperfections appearing after the main coating operation.
    Wet fastener installation coating--A primer or sealant applied 
by dipping, brushing, or daubing to fasteners that are installed 
before the coating is cured.
    Wing coating--A corrosion-resistant topcoat that is resilient 
enough to withstand the flexing of the wings.

    18. Appendix A to Part 63 is amended by adding method 319 in 
numerical order to read as follows:

Appendix A to Part 63--Test Methods

* * * * *

Method 319: Determination of Filtration Efficiency for Paint Overspray 
Arrestors

    1.0  Scope and Application.
    1.1  This method applies to the determination of the initial, 
particle size dependent, filtration efficiency for paint arrestors 
over the particle diameter range from 0.3 to 10 m. The 
method applies to single and multiple stage paint arrestors or paint 
arrestor media. The method is applicable to efficiency 
determinations from 0 to 99 percent. Two test aerosols are used--one 
liquid phase and one solid phase. Oleic acid, a low-volatility 
liquid (CAS Number 112-80-1), is used to simulate the behavior of 
wet paint overspray. The solid-phase aerosol is potassium chloride 
salt (KCl, CAS Number 7447-40-7) and is used to simulate the 
behavior of a dry overspray. The method is limited to determination 
of the initial, clean filtration efficiency of the arrestor. Changes 
in efficiency (either increase or decrease) due to the accumulation 
of paint overspray on and within the arrestor are not evaluated.
    1.2  Efficiency is defined as 1--Penetration (e.g., 70 percent 
efficiency is equal to 0.30 penetration). Penetration is based on 
the ratio of the downstream particle concentration to the upstream 
concentration. It is often more useful, from a mathematical or 
statistical point of view, to discuss the upstream and downstream 
counts in terms of penetration rather than the derived efficiency 
value. Thus, this document uses both penetration and efficiency as 
appropriate.
    1.3  For a paint arrestor system or subsystem which has been 
tested by this method, adding additional filtration devices

[[Page 15028]]

to the system or subsystem shall be assumed to result in an 
efficiency of at least that of the original system without the 
requirement for additional testing. (For example, if the final stage 
of a three-stage paint arrestor system has been tested by itself, 
then the addition of the other two stages shall be assumed to 
maintain, as a minimum, the filtration efficiency provided by the 
final stage alone. Thus, in this example, if the final stage has 
been shown to meet the filtration requirements of Table 1 of 
Sec. 63.745 of subpart GG, then the final stage in combination with 
any additional paint arrestor stages also passes the filtration 
requirements.)
    2.0  Summary of Method.
    2.1  This method applies to the determination of the fractional 
(i.e., particle-size dependent) aerosol penetration of several types 
of paint arrestors. Fractional penetration is computed from aerosol 
concentrations measured upstream and downstream of an arrestor 
installed in a laboratory test rig. The aerosol concentrations 
upstream and downstream of the arrestors are measured with an 
aerosol analyzer that simultaneously counts and sizes the particles 
in the aerosol stream. The aerosol analyzer covers the particle 
diameter size range from 0.3 to 10 m in a minimum of 12 
contiguous sizing channels. Each sizing channel covers a narrow 
range of particle diameters. For example, Channel 1 may cover from 
0.3 to 0.4 m, Channel 2 from 0.4 to 0.5 m, * * * 
By taking the ratio of the downstream to upstream counts on a 
channel by channel basis, the penetration is computed for each of 
the sizing channels.
    2.2  The upstream and downstream aerosol measurements are made 
while injecting the test aerosol into the air stream upstream of the 
arrestor (ambient aerosol is removed with HEPA filters on the inlet 
of the test rig). This test aerosol spans the particle size range 
from 0.3 to 10 m and provides sufficient upstream 
concentration in each of the optical particle counter (OPC) sizing 
channels to allow accurate calculation of penetration, down to 
penetrations of approximately 0.01 (i.e., 1 percent penetration; 99 
percent efficiency). Results are presented as a graph and a data 
table showing the aerodynamic particle diameter and the 
corresponding fractional efficiency.
    3.0  Definitions.
    Aerodynamic Diameter--diameter of a unit density sphere having 
the same aerodynamic properties as the particle in question.
    Efficiency is defined as equal to 1--Penetration.
    Optical Particle Counter (OPC)--an instrument that counts 
particles by size using light scattering. An OPC gives particle 
diameters based on size, index of refraction, and shape.
    Penetration--the fraction of the aerosol that penetrates the 
filter at a given particle diameter. Penetration equals the 
downstream concentration divided by the upstream concentration.
    4.0  Interferences.
    4.1  The influence of the known interferences (particle losses) 
are negated by correction of the data using blanks.
    5.0  Safety.
    5.1  There are no specific safety precautions for this method 
above those of good laboratory practice. This standard does not 
purport to address all of the safety problems, if any, associated 
with its use. It is the responsibility of the user of this method to 
establish appropriate safety and health practices and determine the 
applicability of regulatory limitations prior to use.
    6.0  Equipment and Supplies.
    6.1  Test Facility. A schematic diagram of a test duct used in 
the development of the method is shown in Figure 319-1.

BILLING CODE 6560-50-P

[[Page 15029]]

[GRAPHIC] [TIFF OMITTED] TR27MR98.008



BILLING CODE 6560-50-C

[[Page 15030]]

    6.1.1  The test section, paint spray section, and attached 
transitions are constructed of stainless and galvanized steel. The 
upstream and downstream ducting is 20 cm diameter polyvinyl chloride 
(PVC). The upstream transition provides a 7 deg. angle of expansion 
to provide a uniform air flow distribution to the paint arrestors. 
Aerosol concentration is measured upstream and downstream of the 
test section to obtain the challenge and penetrating aerosol 
concentrations, respectively. Because the downstream ducting runs 
back under the test section, the challenge and penetrating aerosol 
taps are located physically near each other, thereby facilitating 
aerosol sampling and reducing sample-line length. The inlet nozzles 
of the upstream and downstream aerosol probes are designed to yield 
isokinetic sampling conditions.
    6.1.2  The configuration and dimensions of the test duct can 
deviate from those of Figure 319-1 provided that the following key 
elements are maintained: the test duct must meet the criteria 
specified in Table 319-1; the inlet air is HEPA filtered; the blower 
is on the upstream side of the duct thereby creating a positive 
pressure in the duct relative to the surrounding room; the challenge 
air has a temperature between 50 deg. and 100 deg.F and a relative 
humidity of less than 65 percent; the angle of the upstream 
transition (if used) to the paint arrestor must not exceed 7 deg.; 
the angle of the downstream transition (if used) from the paint 
arrestor must not exceed 30 deg.; the test duct must provide a means 
for mixing the challenge aerosol with the upstream flow (in lieu of 
any mixing device, a duct length of 15 duct diameters fulfills this 
requirement); the test duct must provide a means for mixing any 
penetrating aerosol with the downstream flow (in lieu of any mixing 
device, a duct length of 15 duct diameters fulfills this 
requirement); the test section must provide a secure and leak-free 
mounting for single and multiple stage arrestors; and the test duct 
may utilize a 180 deg. bend in the downstream duct.

                     Table 319-1.--QC Control Limits                    
------------------------------------------------------------------------
                                  Frequency and                         
                                   description         Control limits   
------------------------------------------------------------------------
OPC zero count..............  Each Test. OPC        <50 counts per      
                               samples HEPA-         minute.            
                               filtered air.                            
OPC sizing accuracy check...  Daily. Sample         Peak of distribution
                               aerosolized PSL       should be in       
                               spheres.              correct OPC        
                                                     channel.           
Minimum counts per channel    Each Test...........  Minimum total of 500
 for challenge aerosol.                              particle counts per
                                                     channel.           
Maximum particle              Each Test. Needed to  <10% of             
 concentration.                ensure OPC is not     manufacturer's     
                               overloaded.           claimed upper limit
                                                     corresponding to a 
                                                     10% count error.   
Standard Deviation of         Computed for each     <0.10 for 0.3 to 3  
 Penetration.                  test based on the     m         
                               CV of the upstream    diameter.          
                               and downstream       <0.30 for >3 m diameter.      
0% Penetration..............  Monthly.............  <0.01.              
100% Penetration--KCl.......  Triplicate tests      0.3 to 1 m:
                               performed             0.90 to 1.10.      
                               immediately before,  1 to 3 m:  
                               during, or after      0.75 to 1.25.      
                               triplicate arrestor  3 to 10 m: 
                               tests.                0.50 to 1.50.      
100% Penetration--Oleic Acid  Triplicate tests      0.3 to 1 m:
                               performed             0.90 to 1.10.      
                               immediately before,  1 to 3 m:  
                               during, or after      0.75 to 1.25.      
                               triplicate arrestor  3 to 10 m: 
                               tests.                0.50 to 1.50.      
------------------------------------------------------------------------

    6.2  Aerosol Generator. The aerosol generator is used to produce 
a stable aerosol covering the particle size range from 0.3 to 10 
m diameter. The generator used in the development of this 
method consists of an air atomizing nozzle positioned at the top of 
a 0.30-m (12-in.) diameter, 1.3-m (51-in.) tall, acrylic, 
transparent, spray tower. This tower allows larger sized particles, 
which would otherwise foul the test duct and sample lines, to fall 
out of the aerosol. It also adds drying air to ensure that the KCl 
droplets dry to solid salt particles. After generation, the aerosol 
passes through an aerosol neutralizer (Kr85 radioactive source) to 
neutralize any electrostatic charge on the aerosol (electrostatic 
charge is an unavoidable consequence of most aerosol generation 
methods). To improve the mixing of the aerosol with the air stream, 
the aerosol is injected counter to the airflow. Generators of other 
designs may be used, but they must produce a stable aerosol 
concentration over the 0.3 to 10 m diameter size range; 
provide a means of ensuring the complete drying of the KCl aerosol; 
and utilize a charge neutralizer to neutralize any electrostatic 
charge on the aerosol. The resultant challenge aerosol must meet the 
minimum count per channel and maximum concentration criteria of 
Table 319-1.
    6.3  Installation of Paint Arrestor. The paint arrestor is to be 
installed in the test duct in a manner that precludes air bypassing 
the arrestor. Since arrestor media are often sold unmounted, a 
mounting frame may be used to provide back support for the media in 
addition to sealing it into the duct. The mounting frame for 20 in. 
x 20 in. arrestors will have minimum open internal dimensions of 18 
in. square. Mounting frames for 24 in. x 24 in. arrestors will have 
minimum open internal dimensions of 22 in. square. The open internal 
dimensions of the mounting frame shall not be less than 75 percent 
of the approach duct dimensions.
    6.4  Optical Particle Counter. The upstream and downstream 
aerosol concentrations are measured with a high-resolution optical 
particle counter (OPC). To ensure comparability of test results, the 
OPC shall utilize an optical design based on wide-angle light 
scattering and provided a minimum of 12 contiguous particle sizing 
channels from 0.3 to 10m diameter (based on response to 
PSL) where, for each channel, the ratio of the diameter 
corresponding to the upper channel bound to the lower channel bound 
must not exceed 1.5.
    6.5  Aerosol Sampling System. The upstream and downstream sample 
lines must be made of rigid electrically-grounded metallic tubing 
having a smooth inside surface, and they must be rigidly secured to 
prevent movement during testing. The upstream and downstream sample 
lines are to be nominally identical in geometry. The use of a short 
length (100 mm maximum) of straight flexible tubing to make the 
final connection to the OPC is acceptable. The inlet nozzles of the 
upstream and downstream probes must be sharp-edged and of 
appropriate entrance diameter to maintain isokinetic sampling within 
20 percent of the air velocity.
    6.5.1  The sampling system may be designed to acquire the 
upstream and downstream samples using (a) sequential upstream-
downstream sampling with a single OPC, (b) simultaneous upstream and 
downstream sampling with two OPC's, or (c) sequential upstream-
downstream sampling with two OPC's.
    6.5.2  When two particle counters are used to acquire the 
upstream and downstream counts, they must be closely matched in 
flowrate and optical design.
    6.6  Airflow Monitor. The volumetric airflow through the system 
shall be measured with a calibrated orifice plate, flow nozzle, or 
laminar flow element. The measurement device must have an accuracy 
of 5 percent or better.
    7.0  Reagents and Standards.
    7.1  The liquid test aerosol is reagent grade, 98 percent pure, 
oleic acid (Table 319-2). The solid test aerosol is KCl aerosolized 
from a solution of KCl in water. In addition to the test aerosol, a 
calibration aerosol of monodisperse polystyrene latex (PSL) spheres 
is used to verify the calibration of the OPC.

[[Page 15031]]



                                              Table 319-2.--Properties of the Test and Calibration Aerosols                                             
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                        Density,  g/                                                    
                                                        Refractive index                   cm \3\                           Shape                       
--------------------------------------------------------------------------------------------------------------------------------------------------------
Oleic Acid (liquid-phase challenge        1.46 nonabsorbing...........................         0.89  Spherical.                                         
 aerosol).                                                                                                                                              
KCl (solid-phase challenge aerosol).....  1.49........................................         1.98  Cubic or agglomerated cubes.                       
PSL (calibration aerosol)...............  1.59 nonabsorbing...........................         1.05  Spherical.                                         
--------------------------------------------------------------------------------------------------------------------------------------------------------

    8.0  Sample Collection, Preservation, and Storage.
    8.1  In this test, all sampling occurs in real-time, thus no 
samples are collected that require preservation or storage during 
the test. The paint arrestors are shipped and stored to avoid 
structural damage or soiling. Each arrestor may be shipped in its 
original box from the manufacturer or similar cardboard box. 
Arrestors are stored at the test site in a location that keeps them 
clean and dry. Each arrestor is clearly labeled for tracking 
purposes.
    9.0  Quality Control.
    9.1  Table 319-1 lists the QC control limits.
    9.2  The standard deviation () of the penetration (P) 
for a given test at each of the 15 OPC sizing channels is computed 
from the coefficient of variation (CV, the standard deviation 
divided by the mean) of the upstream and downstream measurements as:
[GRAPHIC] [TIFF OMITTED] TR27MR98.009

 For a properly operating system, the standard deviation of the 
penetration is < 0.10 at particle diameters from 0.3 to 3 m 
and less than 0.30 at diameters > 3 m.
    9.3  Data Quality Objectives (DQO).
    9.3.1  Fractional Penetration. From the triplicate tests of each 
paint arrestor model, the standard deviation for the penetration 
measurements at each particle size (i.e., for each sizing channel of 
the OPC) is computed as:
[GRAPHIC] [TIFF OMITTED] TR27MR98.010

where Pi represents an individual penetration 
measurement, and P the average of the 3 (n = 3) individual 
measurements.
    9.3.2  Bias of the fractional penetration values is determined 
from triplicate no-filter and HEPA filter tests. These tests 
determine the measurement bias at 100 percent penetration and 0 
percent penetration, respectively.
    9.3.3  PSL-Equivalent Light Scattering Diameter. The precision 
and bias of the OPC sizing determination are based on sampling a 
known diameter of PSL and noting whether the particle counts peak in 
the correct channel of the OPC. This is a pass/fail measurement with 
no calculations involved.
    9.3.4  Airflow. The precision of the measurement must be within 
5 percent of the set point.
    10.0  Calibration and Standardization.
    10.1  Optical Particle Counter. The OPC must have an up-to-date 
factory calibration. Check the OPC zero at the beginning and end of 
each test by sampling HEPA-filtered air. Verify the sizing accuracy 
on a daily basis (for days when tests are performed) with 1-size PSL 
spheres.
    10.2  Airflow Measurement. Airflow measurement devices must have 
an accuracy of 5 percent or better. Manometers used in conjunction 
with the orifice plate must be inspected prior to use for proper 
level, zero, and mechanical integrity. Tubing connections to the 
manometer must be free from kinks and have secure connections.
    10.3  Pressure Drop. Measure pressure drop across the paint 
arrestor with an inclined manometer readable to within 0.01 in. 
H2O. Prior to use, the level and zero of the manometer, 
and all tubing connections, must be inspected and adjusted as 
needed.
    11.0  Procedure.
    11.1  Filtration Efficiency. For both the oleic acid and KCl 
challenges, this procedure is performed in triplicate using a new 
arrestor for each test.
    11.1.1  General Information and Test Duct Preparation
    11.1.1.1  Use the ``Test Run Sheet'' form (Figure 319-2) to 
record the test information.

Run Sheet

Part 1. General Information

Date and Time:---------------------------------------------------------

Test Operator:---------------------------------------------------------

Test #:----------------------------------------------------------------

Paint Arrestor:
  Brand/Model----------------------------------------------------------

  Arrestor Assigned ID #-----------------------------------------------
    Condition of arrestor (i.e., is there any damage? Must be new 
condition to proceed):

----------------------------------------------------------------------
    Manometer zero and level confirmed?

----------------------------------------------------------------------

Part 2. Clean Efficiency Test

Date and Time:---------------------------------------------------------
Optical Particle Counter:
  20 min. warm up------------------------------------------------------

  Zero count (< 50 counts/min)-----------------------------------------

  Daily PSL check------------------------------------------------------

    PSL Diam: ______ m

  File name for OPC data:----------------------------------------------

Test Conditions:
    Air Flow: ______

    Temp & RH: Temp ______  deg.F RH ______ %

    Atm. Pressure: ______in. Hg
(From mercury barometer)

Aerosol Generator: (record all operating parameters)

----------------------------------------------------------------------

----------------------------------------------------------------------

----------------------------------------------------------------------

----------------------------------------------------------------------

Test Aerosol:
  (Oleic acid or KCl)--------------------------------------------------
Arrestor:
    Pressure drop: at start ______ in. H2O

    at end ______ in. H2O

    Condition of arrestor at end of test (note any physical 
deterioration):

----------------------------------------------------------------------

----------------------------------------------------------------------

Figure 319-2. Test Run Sheet

    Other report formats which contain the same information are 
acceptable.
    11.1.1.2  Record the date, time, test operator, Test #, paint 
arrestor brand/model and its assigned ID number. For tests with no 
arrestor, record none.
    11.1.1.3  Ensure that the arrestor is undamaged and is in 
``new'' condition.
    11.1.1.4  Mount the arrestor in the appropriate frame. Inspect 
for any airflow leak paths.
    11.1.1.5  Install frame-mounted arrestor in the test duct. 
Examine the installed arrestor to verify that it is sealed in the 
duct. For tests with no arrestor, install the empty frame.
    11.1.1.6  Visually confirm the manometer zero and level. Adjust 
as needed.
    11.1.2  Clean Efficiency Test.

[[Page 15032]]

    11.1.2.1  Record the date and time upon beginning this section.
    11.1.2.2  Optical Particle Counter.
    11.1.2.2.1  General: Operate the OPC per the manufacturer's 
instructions allowing a minimum of 20 minutes warm up before making 
any measurements.
11.1.2.2.2  Overload: The OPC will yield inaccurate data if the 
aerosol concentration it is attempting to measure exceeds its 
operating limit. To ensure reliable measurements, the maximum 
aerosol concentration will not exceed 10 percent of the 
manufacturer's claimed upper concentration limit corresponding to a 
10 percent count error. If this value is exceeded, reduce the 
aerosol concentration until the acceptable conditions are met.
    11.1.2.2.3  Zero Count: Connect a HEPA capsule to the inlet of 
the OPC and obtain printouts for three samples (each a minimum of 1-
minute each). Record maximum cumulative zero count. If the count 
rate exceeds 50 counts per minute, the OPC requires servicing before 
continuing.
    11.1.2.2.4  PSL Check of OPC Calibration: Confirm the 
calibration of the OPC by sampling a known size PSL aerosol. 
Aerosolize the PSL using an appropriate nebulizer. Record whether 
the peak count is observed in the proper channel. If the peak is not 
seen in the appropriate channel, have the OPC recalibrated.
    11.1.2.3  Test Conditions:
    11.1.2.3.1  Airflow: The test airflow corresponds to a nominal 
face velocity of 120 FPM through the arrestor. For arrestors having 
nominal 20 in. x 20 in. face dimensions, this measurement 
corresponds to an airflow of 333 cfm. For arrestors having nominal 
face dimensions of 24 in. x 24 in., this measurement corresponds to 
an airflow of 480 cfm.
    11.1.2.3.2  Temperature and Relative Humidity: The temperature 
and relative humidity of the challenge air stream will be measured 
to within an accuracy of +/-2 deg.F and +/-10 percent RH. To protect 
the probe from fouling, it may be removed during periods of aerosol 
generation.
    11.1.2.3.3  Barometric Pressure: Use a mercury barometer. Record 
the atmospheric pressure.
    11.1.2.4  Upstream and Downstream Background Counts.
    11.1.2.4.1  With the arrestor installed in the test duct and the 
airflow set at the proper value, turn on the data acquisition 
computer and bring up the data acquisition program.
    11.1.2.4.2  Set the OPC settings for the appropriate test sample 
duration with output for both printer and computer data collection.
    11.1.2.4.3  Obtain one set of upstream-downstream background 
measurements.
    11.1.2.4.4  After obtaining the upstream-downstream 
measurements, stop data acquisition.
    11.1.2.5  Efficiency Measurements:
    11.1.2.5.1  Record the arrestor pressure drop.
    11.1.2.5.2  Turn on the Aerosol Generator. Begin aerosol 
generation and record the operating parameters.
    11.1.2.5.3  Monitor the particle counts. Allow a minimum of 5 
minutes for the generator to stabilize.
    11.1.2.5.4  Confirm that the total particle count does not 
exceed the predetermined upper limit. Adjust generator as needed.
    11.1.2.5.5  Confirm that a minimum of 50 particle counts are 
measured in the upstream sample in each of the OPC channels per 
sample. (A minimum of 50 counts per channel per sample will yield 
the required minimum 500 counts per channel total for the 10 
upstream samples as specified in Table 319-1.) Adjust generator or 
sample time as needed.
    11.1.2.5.6  If you are unable to obtain a stable concentration 
within the concentration limit and with the 50 count minimum per 
channel, adjust the aerosol generator.
    11.1.2.5.7  When the counts are stable, perform repeated 
upstream-downstream sampling until 10 upstream-downstream 
measurements are obtained.
    11.1.2.5.8  After collection of the 10 upstream-downstream 
samples, stop data acquisition and allow 2 more minutes for final 
purging of generator.
    11.1.2.5.9  Obtain one additional set of upstream-downstream 
background samples.
    11.1.2.5.10  After obtaining the upstream-downstream background 
samples, stop data acquisition.
    11.1.2.5.11  Record the arrestor pressure drop.
    11.1.2.5.12  Turn off blower.
    11.1.2.5.13  Remove the paint arrestor assembly from the test 
duct. Note any signs of physical deterioration.
    11.1.2.5.14  Remove the arrestor from the frame and place the 
arrestor in an appropriate storage bag.
    11.2  Control Test: 100 Percent Penetration Test. A 100 percent 
penetration test must be performed immediately before each 
individual paint arrestor test using the same challenge aerosol 
substance (i.e., oleic acid or KCl) as to be used in the arrestor 
test. These tests are performed with no arrestor installed in the 
test housing. This test is a relatively stringent test of the 
adequacy of the overall duct, sampling, measurement, and aerosol 
generation system. The test is performed as a normal penetration 
test except the paint arrestor is not used. A perfect system would 
yield a measured penetration of 1 at all particle sizes. Deviations 
from 1 can occur due to particle losses in the duct, differences in 
the degree of aerosol uniformity (i.e., mixing) at the upstream and 
downstream probes, and differences in particle transport efficiency 
in the upstream and downstream sampling lines.
    11.3  Control Test: 0 Percent Penetration. One 0 percent 
penetration test must be performed at least monthly during testing. 
The test is performed by using a HEPA filter rather than a paint 
arrestor. This test assesses the adequacy of the instrument response 
time and sample line lag.
    12.0  Data Analysis and Calculations.
    12.1  Analysis. The analytical procedures for the fractional 
penetration and flow velocity measurements are described in Section 
11. Note that the primary measurements, those of the upstream and 
downstream aerosol concentrations, are performed with the OPC which 
acquires the sample and analyzes it in real time. Because all the 
test data are collected in real time, there are no analytical 
procedures performed subsequent to the actual test, only data 
analysis.
    12.2  Calculations.
    12.2.1  Penetration.

Nomenclature

U = Upstream particle count
D = Downstream particle count
Ub = Upstream background count
Db = Downstream background count
P100 = 100 percent penetration value determined 
immediately prior to the arrestor test computed for each channel as:
[GRAPHIC] [TIFF OMITTED] TR27MR98.011

P = Penetration of the arrestor corrected for P100
o = Sample standard deviation
CV = Coefficient of variation = o/mean
E = Efficiency.

    Overbar denotes arithmetic mean of quantity.
    Analysis of each test involves the following quantities:
     P100 value for each sizing channel from the 
100 percent penetration control test,
     2 upstream background values,
     2 downstream background values,
     10 upstream values with aerosol generator on, and
     10 downstream values with aerosol generator on.
    Using the values associated with each sizing channel, the 
penetration associated with each particle-sizing channel is 
calculated as:
[GRAPHIC] [TIFF OMITTED] TR27MR98.012

[GRAPHIC] [TIFF OMITTED] TR27MR98.013

    Most often, the background levels are small compared to the 
values when the aerosol generator is on.
    12.3  The relationship between the physical diameter 
(DPhysical) as measured by the OPC to the aerodynamic 
diameter (DAero) is given by:

[[Page 15033]]

[GRAPHIC] [TIFF OMITTED] TR27MR98.014


Where:

pO = unit density of 1 g/cm3.
pParticle = the density of the particle, 0.89 g/
cm3 for oleic acid.
CCFPhysical = the Cunningham Correction Factor at 
DPhysical.
CCFAero = the Cunningham Correction Factor at 
DAero.

    12.4  Presentation of Results. For a given arrestor, results 
will be presented for:
     Triplicate arrestor tests with the liquid-phase 
challenge aerosol,
     Triplicate arrestor tests with the solid-phase 
challenge aerosol,
     Triplicate 100 percent penetration tests with the 
liquid-phase challenge aerosol,
     Triplicate 100 percent penetration tests with the 
solid-phase challenge aerosol, and
     One 0 percent filter test (using either the liquid-
phase or solid-phase aerosol and performed at least monthly).
    12.4.1  Results for the paint arrestor test must be presented in 
both graphical and tabular form. The X-axis of the graph will be a 
logarithmic scale of aerodynamic diameter from 0.1 to 100 
m. The Y-axis will be efficiency (%) on a linear scale from 
0 to 100. Plots for each individual run and a plot of the average of 
triplicate solid-phase and of the average triplicate liquid-phase 
tests must be prepared. All plots are to be based on point-to-point 
plotting (i.e., no curve fitting is to be used). The data are to be 
plotted based on the geometric mean diameter of each of the OPC's 
sizing channels.
    12.4.2  Tabulated data from each test must be provided. The data 
must include the upper and lower diameter bound and geometric mean 
diameter of each of the OPC sizing channels, the background particle 
counts for each channel for each sample, the upstream particle 
counts for each channel for each sample, the downstream particle 
counts for each channel for each sample, the 100 percent penetration 
values computed for each channel, and the 0 percent penetration 
values computed for each channel.
    13.0  Pollution Prevention.
    13.1  The quantities of materials to be aerosolized should be 
prepared in accord with the amount needed for the current tests so 
as to prevent wasteful excess.
    14.0  Waste Management.
    14.1  Paint arrestors may be returned to originator, if 
requested, or disposed of with regular laboratory waste.
    15.0  References.
    1. Hanley, J.T., D.D. Smith and L. Cox. ``Fractional Penetration 
of Paint Overspray Arrestors, Draft Final Report,'' EPA Cooperative 
Agreement CR-817083-01-0, January 1994.
    2. Hanley, J.T., D.D. Smith, and D.S. Ensor. ``Define a 
Fractional Efficiency Test Method that is Compatible with 
Particulate Removal Air Cleaners Used in General Ventilation,'' 
Final Report, 671-RP, American Society of Heating, Refrigerating, 
and Air-Conditioning Engineers, Inc., December 1993.
    3. ``Project Work and Quality Assurance Plan: Fractional 
Penetration of Paint Overspray Arrestors, Category II,'' EPA 
Cooperative Agreement No. CR-817083, July 1994.

[FR Doc. 98-6999 Filed 3-26-98; 8:45 am]
BILLING CODE 6560-50-P