[Federal Register Volume 68, Number 175 (Wednesday, September 10, 2003)]
[Proposed Rules]
[Pages 53314-53320]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-22808]


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DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration

49 CFR Parts 171, 173 and 180

[Docket No. RSPA-03-14405 (HM-220F)]
RIN 2137-AD78


Hazardous Materials Regulations: Aluminum Cylinders Manufactured 
of Aluminum Alloy 6351-T6 Used in SCUBA, SCBA, and Oxygen Service--
Revised Requalification and Use Criteria

AGENCY: Research and Special Programs Administration (RSPA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: RSPA proposes to amend requirements in the Hazardous Materials 
Regulations (HMR; 49 CFR Parts 171-180) pertaining to aluminum 
cylinders manufactured using aluminum alloy 6351-T6. The purpose of 
this rulemaking initiative is to enhance safety, minimize the potential 
for personal injury and property damage during the cylinder filling 
process, and adopt a standard for early detection of sustained load 
cracking (SLC) to reduce the risk of a cylinder rupture.

DATES: Comments must be received by November 10, 2003.

ADDRESSES: You may submit comments by any of the following methods:
    [sbull] Web Site: http://dms.dot.gov. Follow the instructions for 
submitting comments on the DOT electronic docket site.
    [sbull] Fax: 1-202-493-2251.
    [sbull] Mail: Docket Management System; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-001.
    [sbull] Hand Delivery: To the Docket Management System; Room PL-401 
on the plaza level of the Nassif Building, 400 Seventh Street, SW., 
Washington, DC between 9:00 am and 5:00 pm, Monday through Friday, 
except Federal Holidays.
    Instructions: You must include the agency name and docket number 
RSPA -03-14405 (HM-220F) or the Regulatory Identification Number (RIN) 
for this notice at the beginning of your comment. For detailed 
instructions on submitting comments and additional information on the 
rulemaking process, see the Public Participation section of this 
document. Note that all comments received will be posted without change 
to http://dms.dot.gov including any personal information provided. 
Please see the Privacy Act section of this document.
    Docket: You may view the public docket through the Internet at 
http://dms.dot.gov or in person at the Docket Management System office 
at the above address.

FOR FURTHER INFORMATION CONTACT: Mark Toughiry, Office of Hazardous 
Materials Technology, (202) 366-4545, or Charles E. Betts, Office of 
Hazardous Materials Standards, (202) 366-8553; RSPA, U.S. Department of 
Transportation, 400 Seventh Street SW., Washington, DC 20590-0001.

SUPPLEMENTARY INFORMATION: 

Contents

I. Background
II. Public Participation
III. Section-By-Section Review
IV. Regulatory Analyses and Notices
    A. Executive Order 12866 and DOT Regulatory Polices and 
Procedures
    B. Executive Order 13132
    C. Executive Order 13175
    D. Regulatory Flexibility Act, Executive Order 13272, and DOT 
Procedures and Policies
    E. Paperwork Reduction Act
    F. Regulation Identifier Number (RIN)
    G. Unfunded Mandates Reform Act
    H. Environmental Assessment
    I. Privacy Act

I. Background

    Cylinders made of aluminum alloy 6351-T6 are known to be 
susceptible to sustained load cracking (SLC) in the neck and shoulder 
area of the cylinder. The majority of the SLC-related ruptures have 
occurred in self-contained underwater breathing apparatus (SCUBA), 
self-contained breathing apparatus (SCBA), and oxygen services. Since 
1994, the Research and Special Programs Administration (RSPA, we) has 
been notified of twelve suspected SLC ruptures of cylinders 
manufactured of aluminum alloy 6351-T6. Five of the twelve ruptures 
resulted in serious injuries. RSPA's review of manufacturers' data 
revealed that there have been several thousand cylinders

[[Page 53315]]

that leaked, and many additional cylinders have been found with cracks 
in the cylinder's neck during the normal requalification process. 
Manufacturers of cylinders made from the 6351-T6 alloy have performed 
research, testing and analysis to determine whether there is any 
correlation between SLC and the probability of a cylinder rupture. The 
data indicated that the cylinders would leak but not rupture when 
operated at marked service pressure. It was also found that the 
probability of cracking increases with an increase in stress levels. We 
performed additional metallurgical analysis on several ruptured 
cylinders to verify the cause of failure and failure mode. (See the 
metallurgical analysis reports at http://hazmat.dot.gov/3al_cyls_info.htm.) Those metallurgical analyses revealed that SLC caused the 
cylinder ruptures, but the results were inconclusive as to why the 
cylinders abruptly ruptured instead of leaked. United States 
manufacturers discontinued using aluminum alloy 6351-T6 in mid-1990, 
replacing it with aluminum alloy 6061-T6, which is not susceptible to 
SLC. We estimate that approximately four million U.S. cylinders 
manufactured from aluminum alloy 6351-T6 are in use in SCUBA, SCBA, and 
oxygen services.
    The primary domestic manufacturers of DOT 3AL cylinders currently 
in service are Luxfer USA; Walter Kidde Co.; Cliff Impact Division of 
Parker Hannifin Corporation; and Catalina Cylinders. The majority of 
the cylinders are being used in six major services: (1) SCUBA, (2) 
SCBA, (3) carbon dioxide, (4) oxygen, (5) industrial gases, and (6) 
fire extinguishers.
    Cylinders manufactured of aluminum alloy 6351-T6 prior to July 1990 
include seamless aluminum cylinders marked ``DOT 3AL'', including those 
marked with ``DOT 3AL'' above or near one of the following exemption or 
special permit numbers: 6498, 7042, 8107, 8364, and 8422. In addition, 
unless determined otherwise, affected individuals should assume that a 
DOT 3AL or DOT-E 7235 cylinder manufactured outside the United States 
is constructed of aluminum alloy 6351-T6.
    On August 8, 2002, we published a final rule (Docket HM-220D, 67 FR 
51626) that amended the requirements of the HMR applicable to the 
maintenance, requalification, repair, and use of DOT specification 
cylinders. In that final rule, we added the following amendments 
pertaining to DOT specification cylinders made with aluminum alloy 
6351-T6:
    [sbull] We removed the authorization for the manufacture of DOT 
specification cylinders from aluminum alloy 6351-T6 because cylinders 
manufactured with this aluminum alloy have a greater risk of failure 
than other aluminum cylinders.
    [sbull] We prohibited these cylinders for Hazard Zone A materials 
effective on October 1, 2002. After that date, cylinders made of 
aluminum alloy 6351-T6 may not be filled and offered for transportation 
in toxic inhalation hazard service.
    [sbull] We prohibited the use of cylinders manufactured of aluminum 
alloy 6351-T6 for gases having pyrophoric properties.
    [sbull] We required a DOT specification or exemption cylinder made 
of aluminum allow 6351-T6 to be inspected for evidence of sustained 
load cracking in the neck and shoulder area.
    As stated earlier, the majority of the SLC-related ruptures 
occurred in SCUBA, SCBA and oxygen services. Additionally, for these 
services, the probability of cracking increases due to the increased 
frequency with which cylinders in these services are filled. We 
recognize that cylinders used in beverage service are also filled on a 
frequent basis. However, beverage service cylinders typically are 
filled to lower pressures than cylinders used in SCUBA, SCBA, and 
oxygen services, thereby reducing the stress levels to which beverage 
service cylinders are subjected. Moreover, in SCUBA and SCBA services, 
the cylinder is attached to the back of a diver or firefighter, which 
substantially increases the risk of injury or fatality in the event of 
a rupture. Similarly, an oxygen cylinder may be placed close to a 
patient in the hospital or home. SLC could also result in an oxygen 
leak that may cause an explosion. Therefore, because of the higher risk 
in SCUBA, SCBA and oxygen services, this rulemaking (HM-220F) proposes 
to adopt a standard for early detection of SLC to reduce the risk of a 
cylinder rupture.
    We performed an analysis of costs associated with operating 
cylinders manufactured of aluminum alloy 6351-T6. The economic 
evaluation considered and compared the costs of three possible 
alternatives: (1) Leaving the cylinder in service without taking any 
additional measures to reduce the risk, (2) removing all cylinders made 
of aluminum alloy 6351-T6 from service, or (3) performing a non-
destructive examination (NDE) at the time of the cylinder's periodic 
requalification and requiring additional operational controls (OC) 
during the cylinder filling process. Estimating the societal cost of 
injuries or fatalities that would otherwise be avoided if SLC were 
eliminated is complicated. The uncertainties due to the 
unpredictability at which ruptures occur and the likelihood that aging 
cylinders may be progressively more prone to SLC makes option three to 
most prudent of the three options. It also addresses a known safety 
problem without imposing excessive costs.
    DOT 3AL cylinders must be requalified every five years (twelve 
years for fire extinguishers) in accordance with Sec.  180.205 of the 
HMR. The requalification performed under Sec.  180.205 includes a 
visual inspection (internal and external) and a volumetric expansion 
test. The requalification does not include a specific NDE of the 
cylinder neck or crown areas for detection of SLC. However, we 
understand that in addition to the visual inspection and volumetric 
expansion test, many users and requalifiers are currently performing an 
eddy current examination. Approximately 2,000 eddy current devices have 
been purchased by various cylinder requalifiers to examine aluminum 
cylinders for SLC. Cylinder manufacturers report that a large number of 
affected cylinders have been removed from service because of flaws 
discovered during eddy current examinations.
    We evaluated three NDE methods--visual examination (VT), eddy 
current examination (ET), and ultrasonic examination (UT)--to detect a 
critical-size crack. A cylinder with a critical-size crack must be 
removed from service upon detection of the crack. Under the direction 
of RSPA, Texas Research Institute (TRI) evaluated these three NDE (VT, 
ET, UT) methods by performing blind examinations that were applied by 
individuals of varying skill levels (See the Nondestructive Inspection 
of High Pressure Aluminum Gas Cylinder, Final Report, dated September 
2000, at http://hazmat.dot.gov/ohmforms.htm#other). TRI determined that 
each NDE method was capable of detecting SLC, but the detectability 
using VT was limited by external factors, such as the inspector's eye 
sight, lighting, position of the crack, and alertness of the examiner. 
TRI also determined that UT must be applied by a certified technician 
to produce accurate results in detecting SLC. TRI concluded that ET 
combined with a visual inspection (VT) provides the most accurate and 
practical examination for detecting SLC. Both ET and VT can be 
conducted by a requalifier with minimal training.
    In this NPRM, we propose to require cylinders manufactured of 
aluminum alloy 6351-T6 used in SCUBA (diving), SCBA (firefighting), and 
oxygen service

[[Page 53316]]

to undergo a combined visual and eddy current examination (referred to 
as ``VE'' in this rulemaking) in order to requalify the cylinders in 
accordance with Sec.  180.205. We propose to add a new Appendix C to 
part 180, to specify the procedure to be used to conduct the ET 
examination. No person may requalify a DOT specification or exemption 
cylinder in accordance with Sec.  180.209 of this chapter unless that 
person has been issued a requalifier identification number (RIN) as 
provided in Sec.  107.805(d). Each person who holds a valid RIN and 
performs an ET in accordance with Sec.  180.205 must notify RSPA in 
writing in accordance with the procedural requirements in Sec.  
107.805. We are also proposing that suitable safeguards be provided to 
protect personnel and facilities should failure occur during the 
filling of cylinders manufactured of aluminum alloy 6351-T6 used in 
SCUBA, SCBA, and oxygen services. Additionally, we are recommending 
that only individuals essential to the filling process be allowed in 
the vicinity of the cylinder during the filling process.
    Although we believe that the twelve reported SLC suspected ruptures 
under-represent the extent of the SLC issue, we do not have sufficient 
data to determine whether the SLC related ruptures extend beyond those 
services discussed above. Therefore, we are requesting additional 
information from manufactures and users who are aware of the rupture of 
any DOT 3AL cylinder or any other cylinder manufactured from aluminum 
alloy 6351-T6, whether the incident was domestic or foreign, to submit 
the information in their comments to this rulemaking. More broadly, we 
invite commenters to address the issue of whether the new inspection 
requirements proposed in this NPRM should apply to cylinders 
manufactured of aluminum alloy 6351-T6 and used in services other than 
SCUBA, SCBA, or oxygen.

II. Public Participation

    You should identify the docket number RSPA-03-14405 (HM-220F) at 
the beginning of your comments. You should submit two copies of your 
comments, if you submit them by mail. If you wish to receive 
confirmation that RSPA received your comments, you should include a 
self-addressed stamped postcard. Internet users may access all comments 
received by DOT at http://dms.dot.gov.

III. Section-by-Section Review

Part 171

Section 171.7

    As a result of RSPA's proposal to require cylinders manufactured of 
aluminum alloy 6351-T6 used in SCUBA, SCBA, and oxygen service to 
undergo an NDE, we are proposing to revise the incorporation by 
reference entry CGA Pamphlet C-6.1, ``Standards for Visual Inspection 
of High Pressure Aluminum Compressed Gas Cylinders, 1995,'' under the 
Compressed Gas Association, Inc., to incorporate by reference the 2002 
edition of this pamphlet. The 2002 edition of the standard has 
provisions discussing cleaning methods that may result in the removal 
of cylinder wall material. It also contains a new requirement that all 
aluminum cylinders be internally inspected for cracks in the neck 
region. Persons who may be affected by these changes should review the 
standard to determine any potential impacts on their operations.

Part 173

Section 173.302

    We are proposing to revise this section by adding a new paragraph 
(e) to require that operational controls must be in place during the 
filling process, for cylinders manufactured of aluminum alloy 6351-T6. 
The operational controls will reduce the risk of injury and property 
damage during the filling process.

Part 180

Section 180.209

    We are proposing to revise in paragraph (a), the entry for the DOT 
3AL cylinder in the ``Requalification of Cylinders'' table to add a 
reference to the new paragraph (m). In addition, we are proposing to 
add a new paragraph (m) to include a non-destructive examination for 
cylinders manufactured of aluminum alloy 6351-T6. The non-destructive 
examination will be used to detect sustained load cracking in the neck 
and shoulder area.

Section 180.213

    We are proposing to revise paragraph (d) and to add a new paragraph 
(f)(8) to specify the requalification marking requirements for those 
aluminum cylinders that successfully pass the combined eddy current 
examination and visual inspection.

IV. Regulatory Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and Procedures

    This proposed rule is not considered a significant regulatory 
action under section 3(f) of Executive Order 12866 and, therefore, was 
not reviewed by the Office of Management and Budget. The proposed rule 
is not considered a significant rule under the Regulatory Policies and 
Procedures of the Department of Transportation [44 FR 11034]. A 
regulatory analysis is available for review in the docket.
    The compliance costs associated with this rule are minimal. The 
regulatory analysis revealed the increased cost for performing an NDE 
and OC to be small compared to the cost and safety risks of ``doing 
nothing,'' and it is significantly less than the cost of ``removing all 
cylinders from service.'' The economic evaluation data were based on 
information obtained from cylinder manufacturers, industrial gas 
companies, cylinder inspectors, and on metallurgical evaluation of the 
ruptured cylinders. We determined that the removal of cylinders 
manufactured of aluminum alloy 6351-T6 will result in a significant 
economic impact to cylinder owners and may cause a serious shortage of 
breathing air cylinders used in fire fighting and medical applications. 
Therefore, based on the risk assessment and regulatory analysis, we 
conclude that a requirement to perform an eddy current examination 
combined with a visual inspection at the required five-year 
requalification period is the best alternative. Since the NDE would 
take place at the time of the currently required five-year 
requalification period, the cost would be reduced substantially. We 
estimate the cost of volumetric expansion test and internal visual 
inspection that is required under the current regulation to be $5.00 
per cylinder every five years. We estimate that the eddy current 
examination combined with the current volumetric expansion test and 
visual inspection to be $7.25 per cylinder every five years. The 
estimated $7.25 per cylinder includes the initial start-up cost (e.g., 
training and cost of purchasing eddy current equipment). Therefore, we 
estimate the additional annual cost of the eddy current examination 
combined with the visual inspection to be $0.45 per cylinder. The 
average annual cost of this examination is the annual cost per cylinder 
multiplied by the number of cylinders, or $1,800,000. The cost of 
additional operational controls is nominal.

[[Page 53317]]

    While researching a viable NDE method that could accurately detect 
SLC, we made a significant effort to reduce the risk of injury by 
educating cylinder users regarding the risk of using cylinders 
manufactured of aluminum alloy 6351-T6. As a result of this effort, we 
published the following safety advisory notices in the Federal Register 
between 1983 and 1999, concerning SLC in cylinders manufactured of 
aluminum alloy 6351-T6:
Aug. 11, 1983; Vol. 48, No. 156; pg. 36559
Feb. 27, 1984; Vol. 49, No. 39; pg. 7182
Nov. 01, 1984; Vol. 49, No. 213; pg. 44047
Jul. 17, 1985; Vol. 50, No. 137; pg. 29037
Aug. 15, 1985; Vol. 50, No. 158; pg. 32944
Jul. 10, 1987; Vol. 52, No. 132; pg. 26027
Mar. 24, 1993; Vol. 58, No. 55; pg. 15895
Aug. 10, 1993; Vol. 58, No. 152; pg. 42620
Jul. 26, 1994; Vol. 59, No. 142; pg. 38028
Dec. 14, 1998; Vol. 63, No. 239; pg. 68819
Oct. 18, 1999; Vol. 64, No. 2001; pg. 56243

B. Executive Order 13132

    This proposed rule has been analyzed in accordance with the 
principles and criteria contained in Executive Order 13132 
(``Federalism''). This proposed rule would preempt State, local and 
Indian tribe requirements, but does not propose any regulation that has 
direct effects on the States, the relationship between the national 
government and the States, or the distribution of power and 
responsibilities among the various levels of government. Therefore, the 
consultation and funding requirements of Executive Order 13132 do not 
apply.
    The Federal hazardous material transportation law, 49 U.S.C. 5101-
5127, contains an express preemption provision (49 U.S.C. 5125(b)) that 
preempts State, local, and Indian tribe requirements on certain covered 
subjects. Covered subjects are:
    (1) The designation, description, and classification of hazardous 
material;
    (2) the packing, repacking, handling, labeling, marking, and 
placarding of hazardous material;
    (3) the preparation, execution, and use of shipping documents 
related to hazardous material and requirements related to the number, 
contents, and placement of those documents;
    (4) the written notification, recording, and reporting of the 
unintentional release in transportation of hazardous material; or
    (5) the design, manufacturing, fabricating, marking, maintenance, 
reconditioning, repairing, or testing of a packaging or container 
represented, marked, certified, or sold as qualified for use in 
transporting hazardous material.
    This proposed rule covers items 2 and 5 and would preempt any 
State, local, or Indian tribe requirements not meeting the 
``substantively the same'' standard.
    Federal hazardous materials transportation law provides at Sec.  
5125(b)(2) that, if the Secretary of Transportation issues a regulation 
concerning any of the covered subjects, the Secretary must determine 
and publish in the Federal Register the effective date of Federal 
preemption. The effective date may not be earlier than the 90th day 
following the date of issuance of the final rule and not later than two 
years after the date of issuance. We propose that the effective date of 
Federal preemption will be 90 days from publication of a final rule in 
the Federal Register.

C. Executive Order 13175

    This proposed rule has been analyzed in accordance with the 
principles and criteria contained in Executive Order 13175 
(``Consultation and Coordination with Indian Tribal Governments''). 
Because this proposed rule does not have tribal implications, does not 
impose substantial direct compliance costs, and is not required by 
statute, the funding and consultation requirements of Executive Order 
13175 do not apply.

D. Regulatory Flexibility Act, Executive Order 13272, and DOT 
Procedures and Policies

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires an 
agency to review regulations to assess their impact on small entities 
unless the agency determines a rule is not expected to have a 
significant economic impact on a substantial number of small entities. 
This rule imposes only minimal new costs of compliance on the regulated 
industry. Based on the assessment in the regulatory evaluation, I 
hereby certify that while this rule applies to a substantial number of 
small entities, there will not be a significant economic impact on 
those small entities. A detailed Regulatory Flexibility analysis is 
available for review in the docket.
    This proposed rule has been developed in accordance with Executive 
Order 13272 (``Proper Consideration of Small Entities in Agency 
Rulemaking'') and DOT's procedures and policies to promote compliance 
with the Regulatory Flexibility Act to ensure that potential impacts of 
draft rules on small entities are properly considered.

E. Paperwork Reduction Act

    This proposed rule may result in a modest increase in annual burden 
and costs based on a new information collection requirement. These 
proposals regarding the shipment of aluminum cylinders which result in 
a new information collection requirement will be submitted to OMB for 
review and approval. RSPA currently has an approved information 
collection under OMB Control No. 2137-0022, ``Testing, Inspection, and 
Marking Requirements for Cylinders.''
    Section 1320.8(d), Title 5, Code of Federal Regulations requires 
that RSPA provide interested members of the public and affected 
agencies an opportunity to comment on information collection and 
recordkeeping requests. This notice identifies a new information 
collection request that RSPA will submit to OMB for approval based on 
the requirements in this proposed rule. RSPA has developed burden 
estimates to reflect changes in this proposed rule. RSPA estimates that 
the total information collection and recordkeeping burden as proposed 
in this rule would be as follows:
    OMB No. 2137-0022:
    Total Annual Number of Respondents: 139,352.
    Total Annual Responses: 153,287.
    Total Annual Burden Hours: 271,461.
    Total Annual Burden Cost: $2,615,515.
    Total One-Time Start-Up Cost: $964,000.
    RSPA specifically requests comments on the information collection 
and recordkeeping burdens associated with developing, implementing, and 
maintaining these requirements for approval under this proposed rule.
    Direct your requests for a copy of the information collection to 
Deborah Boothe or T. Glenn Foster, Office of Hazardous Materials 
Standards (DHM-10), Research and Special Programs Administration, Room 
8102, 400 Seventh Street, SW., Washington, DC 20590-0001, Telephone 
(202) 366-8553.
    Address written comments to the Dockets Unit as identified in the 
ADDRESSES section of this rulemaking. We must receive your comments 
prior to the close of comment period identified in the DATES section of 
this rulemaking. Under the Paperwork Reduction Act of 1995, no person 
is required to respond to an information collection unless it displays 
a valid OMB control number. If these proposed requirements are adopted 
in a final rule, RSPA will submit the revised information collection 
and recordkeeping requirements to the

[[Page 53318]]

Office of Management and Budget for approval.

F. Regulation Identifier Number (RIN)

    A regulation identifier number (RIN) is assigned to each regulatory 
action listed in the Unified Agenda of Federal Regulations. The 
Regulatory Information Service Center publishes the Unified Agenda in 
April and October of each year. The RIN number contained in the heading 
of this document can be used to cross-reference this action with the 
Unified Agenda.

G. Unfunded Mandates Reform Act

    This proposed rule does not impose unfunded mandates under the 
Unfunded Mandates Reform Act of 1995. It does not result in costs of 
$100 million or more to either State, local or tribal governments, in 
the aggregate, or to the private sector, and is the least burdensome 
alternative that achieves the objective of the rule.

H. Environmental Assessment

    The National Environmental Policy Act of 1969 (NEPA), as amended 
(42 U.S.C. 4321-4347), requires Federal agencies to consider the 
consequences of major federal actions and prepare a detailed statement 
on actions significantly affecting the quality of the human 
environment. There are no significant environmental impacts associated 
with this proposed rule. RSPA proposes to amend requirements in the HMR 
pertaining to DOT 3AL aluminum cylinders. The purpose of this 
rulemaking initiative is to minimize personal injury during the 
cylinder filling process and to adopt a standard for early detection of 
sustained load cracking in order to reduce the risk of a cylinder 
rupture. Adopting a standard for early detection of sustained load 
cracking in order to reduce the risk of a cylinder rupture has no 
potential for environmental damage or contamination.

I. Privacy Act

    Anyone is able to search the electronic form of all comments 
received into any of our dockets by the name of the individual 
submitting the comment (or signing the comment, if submitted on behalf 
of an association, business, labor union, etc.). You may review DOT's 
complete Privacy Act Statement in the Federal Register published on 
April 11, 2000 (Volume 65, Number 70; Pages 19477-78) or you may visit 
http://dms.dot.gov.

List of Subjects

49 CFR Part 171

    Exports, Hazardous materials transportation, Hazardous waste, 
Imports, Incorporation by reference, Reporting and recordkeeping 
requirements.

49 CFR Part 173

    Hazardous materials transportation, Incorporation by reference, 
Packaging and containers, Radioactive materials, Reporting and 
recordkeeping requirements, Uranium.

49 CFR Part 180

    Hazardous materials transportation, Incorporation by reference, 
Motor vehicle safety, Packaging and containers, Reporting and 
recordkeeping requirements.

    In consideration of the foregoing, we propose to amend 49 CFR 
Chapter I, Subchapter C, as follows:

PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS

    1. The authority citation for part 171 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.

    2. In Sec.  171.7, in the table in paragraph (a)(3), the entry for 
pamphlet C-6.1 under the Compressed Gas Association, Inc., is revised 
to read as follows:


Sec.  171.7  Reference material.

    (a) * * *
* * * * *
    (3) Table of material incorporated by reference.

----------------------------------------------------------------------------------------------------------------
         Source and name of material                                   49 CFR reference
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
Compressed Gas Association, Inc.,
 
                                                  * * * * * * *
CGA Pamphlet C-6.1, Standards for Visual      180.205; 180.209; Appendix C to part 180.
 Inspection of High Pressure Aluminum
 Compressed Gas Cylinders, 2002.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENT AND PACKAGES

    3. The authority citation for part 173 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127, 44701; 49 CFR 1.45, 1.53

    4. In Sec.  173.302, paragraph (e) is added to read as follows:


Sec.  173.302  Filling of cylinders with nonliquefied (permanent) 
compressed gases.

* * * * *
    (e) Aluminum cylinders manufactured of 6351-T6 aluminum alloy. 
Suitable safeguards must be provided to protect personnel and 
facilities should failure occur while filling cylinders manufactured of 
aluminum alloy 6351-T6 used in self-contained underwater breathing 
apparatus (SCUBA), self-contained breathing apparatus (SCBA), and 
oxygen services. The cylinder filler should allow only those 
individuals essential to the filling process to be in the vicinity of 
the cylinder during the filling process.

PART 180--CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS

    5. The authority citation for part 180 continues to read as 
follows:

    Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53.

    6. In Sec.  180.209 in paragraph (a), in the ``Requalification of 
Cylinders table'' the entry ``DOT 3AL'' is revised, and a new paragraph 
(m) is added to read as follows:


Sec.  180.209  Requirements for requalification of specification 
cylinders.

* * * * *
    (a) * * *

[[Page 53319]]



               Table 1.--Requalification of Cylinders \1\
------------------------------------------------------------------------
                                     Minimum test
    Specification under which      pressure (psig.)     Requalification
        cylinder was made                 \2\           period (years)
------------------------------------------------------------------------
 
                              * * * * * * *
DOT 3AL.........................  5/3 times service   5 or 12 (see Sec.
                                   pressure.            180.209(j) and
                                                       Sec.   180.209(m)
                                                       \3\).
 
                             * * * * * * *
------------------------------------------------------------------------
\1\ Any cylinder not exceeding 2 inches outside diameter and less than 2
  feet in length is excepted from volumetric expansion test.
\2\ For cylinders not marked with a service pressure, see Sec.
  173.301(e)(1) of this subchapter.
\3\ This provision does not apply to aluminum cylinders used in fire
  extinguisher service.

* * * * *
    (m) Aluminum cylinders manufactured of 6351-T6 aluminum alloy. In 
addition to the periodic requalification and marking described in Sec.  
180.205, cylinders manufactured of aluminum alloy 6351-T6 used in self-
contained underwater breathing apparatus (SCUBA), self-contained 
breathing apparatus (SCBA), and oxygen service must be requalified and 
inspected for sustained load cracking in accordance with the non-
destructive examination method described in the following table. 
Cylinders with sustained load cracking that has expanded into the neck 
threads must be condemned in accordance with Sec.  180.205(i). This 
provision does not apply to aluminum cylinders used in fire 
extinguisher service and to cylinders used to transport carbon dioxide 
or industrial gases. Requalification and inspection of the aluminum 
cylinders must conform to the following table.

 Requalification and Inspection of Aluminum Cylinders Made of Aluminum Alloy 6351-T6 Manufactured Prior to July
                                                      1990
----------------------------------------------------------------------------------------------------------------
                                                                     Sustained load cracking    Requalification
      Requalification requirement        Examination procedure \1\    rejection criteria \2\     period (years)
----------------------------------------------------------------------------------------------------------------
Eddy current examination combined with   In accordance with         2 threads long...........                 5
 visual inspection.                       Appendix C of this part.
                                          Visual inspection--In
                                          accordance with CGA
                                          Pamphlet C-6.1 (IBR; see
                                          Sec.   171.1 of this
                                          subchapter).
----------------------------------------------------------------------------------------------------------------
\1\ The requalifier performing eddy current must be familiar with the eddy current equipment and standardize
  (calibrate) the system in accordance with the requirements provided in Appendix C to this part. The
  requalifier must perform the visual inspection of the cylinder neck and shoulder in accordance with CGA
  Pamphlet C-6.1 (IBR; see Sec.   171.7 of this subchapter).
\2\ The eddy current must be applied from the inside of the cylinder's neck to detect any sustained load
  cracking that has expanded into the neck threads.

    7. In Sec.  180.213, paragraph (d) is revised and a new paragraph 
(f)(8) is added to read as follows:


Sec.  180.213  Requalification markings.

* * * * *
    (d) Requalification markings. Each cylinder that has successfully 
passed requalification must be marked with the RIN set in a square 
pattern, between the month and year of the requalification date. The 
first character of the RIN must appear in the upper left corner of the 
square pattern; the second in the upper right; the third in the lower 
right; and the fourth in the lower left. Example: A cylinder 
requalified in September 1998, and approved by a person who has been 
issued RIN ``A123'', would be marked plainly and permanently into the 
metal of the cylinder in accordance with location requirements of the 
cylinder specification or on a metal plate permanently secured to the 
cylinder in accordance with paragraph (b) of this section. An example 
of the markings prescribed in this paragraph (d) is a follows:
[GRAPHIC] [TIFF OMITTED] TP10SE03.000

Where:

``9'' is the month of requalification
``A123'' is the RIN
``98'' is the year of requalification, and
``X'' represents the symbols described in paragraphs (f)(2) through 
(f)(8) of this section.
* * * * *
    (f) * * *
* * * * *
    (8) For designation of the eddy current examination combined with a 
visual inspection, the marking is as illustrated in paragraph (d) of 
this section, except that the ``X'' is replaced with the letters 
``VE''.
    8. In Part 180, Appendix C is added to read as follows:

Appendix C to Part 180--Acceptable Eddy Current Examination for 
Cylinders Manufactured of Aluminum Alloy 6351-T6

    1. This examination procedure is designed to detect critical 
size cracks in cylinders made of aluminum alloy 6351-T6.
    2. Eddy Current Equipment--Equipment, such as Visual Plus, 
Visual Eddy, or equivalent non-destructive testing equipment must be 
capable of detecting the notches on the standard reference ring.
    3. Eddy Current Reference Ring--The reference ring must be 
produced to represent the outer diameter (O.D.) of each cylinder to 
be tested. The reference ring must include artificial notches that 
will simulate a neck crack. The size of the artificial notch (depth 
and length) must be obtained from the eddy current equipment 
manufacturer. The standard reference must have a drawing that 
includes the depth of each notch, diameter and alloy.
    4. Eddy Current Equipment Standardization--Each day prior to 
testing, the eddy current equipment must be standardized for each 
size (O.D.) of aluminum cylinder, using the reference ring described 
in item number 3 above. The minimum standardization requirements of 
the eddy current equipment are as follows:

[[Page 53320]]

    (i) Screw reference ring onto the probe until the base of the 
reference ring is flush with the probe bottom, then back off two 
turns.
    (ii) Warm the equipment for at least 20 minutes.
    (iii) Set up the system between 150-215 kHz.
    (iv) Locate the line \1/4\ from the screen bottom.
    (v) Rotate the reference ring counterclockwise and observe the 
spike signal on the screen. Adjust the gain (using gain control) 
until the spike peaks to \3/4\ of the screen height (from home 
position to \1/4\ of screen from the top).
    (vi) When spike signals break the centerline the threshold light 
must come on.
    5. Eddy Current Examination and Visual Inspection--A written 
examination procedure for performing the eddy current examination 
and visual inspection must be kept at each facility that performs 
examinations under this procedure. The visual inspection procedure 
must be in accordance with CGA pamphlet C-6.1 (IBR; see Sec.  171.1 
of this subchapter).
    At a minimum, the written examination procedure for performing 
the eddy current must include the following instructions:
    (i) Remove the probe from the reference ring and screw probe 
clockwise half-way into cylinder's neck and press the sweep (e.g. 
NULL) button.
    (ii) Continue rotating the probe clockwise until the threshold 
line moves off top of the screen, indicating probe is inside 
shoulder area (probe is in air).
    (iii) Rotate probe counterclockwise towards the outlet of the 
cylinder until the threshold line appears on the screen indicating 
the probe is in the cylinder's neck.
    (iv) Press the sweep (e.g. NULL) button to ensure that the line 
is positioned on screen, preferably at home position.
    (v) Watch for spike signals indicating cracks. Mark positions 
with a grease pencil. When the spike occurs rotate the probe 360 
degrees.
    (vi) Check for successive indications at same angle indicating 
multiple cracks. Two successive spikes that break the threshold at 
the same angle indicate a two thread crack. A two thread crack is 
the rejection criteria.
    (vii) Perform the visual inspection for confirmation.
    6. Examination equipment records.
    Records of eddy current inspection shall contain the following 
information:
    (i) Equipment manufacturer, model number and serial number.
    (ii) Probe description and unique identification (e.g., serial 
number, part number, etc.).
    7. Eddy current examination reporting and record retention 
requirements.
    Daily records of eddy current examinations must be maintained by 
the person who performs the requalification until either the 
expiration of the requalification period or until the cylinder is 
again requalified, whichever occurs first. These records must be 
made available for inspection by a representative of the Department 
on request. Eddy current examination records shall contain the 
following information:
    (i) Specification of each standard reference ring used to 
perform the eddy current examination.
    (ii) DOT specification or exemption number, manufacturer's name 
or symbol, owner's name or symbol and date of manufacture.
    (iii) Name of test operator performing the eddy current 
examination.
    (iv) Date of eddy current examination.
    (v) Location and type of defect on the cylinder crown or the 
threaded neck (e.g., 5 threads).
    (vi) Acceptance/rejection results (e.g. pass or fail).
    (vii) Legible identification of test operator.

    Issued in Washington, DC on September 3, 2003, under authority 
delegated in 49 CFR part 106.
Frits Wybenga,
Deputy Associate Administrator for Hazardous Materials Safety.

[FR Doc. 03-22808 Filed 9-9-03; 8:45 am]
BILLING CODE 4910-60-P