Hazardous Materials: Miscellaneous Amendments Pertaining to DOT-Specification Cylinders (RRR)

Federal Register, Volume 81 Issue 143 (Tuesday, July 26, 2016)

Federal Register Volume 81, Number 143 (Tuesday, July 26, 2016)

Proposed Rules

Pages 48977-49022

From the Federal Register Online via the Government Publishing Office www.gpo.gov

FR Doc No: 2016-16689

Page 48977

Vol. 81

Tuesday,

No. 143

July 26, 2016

Part III

Department of Transportation

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Pipeline and Hazardous Materials Safety Administration

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49 CFR Parts 107, 171, 172, et al.

Hazardous Materials: Miscellaneous Amendments Pertaining to DOT-

Specification Cylinders (RRR); Proposed Rule

Page 48978

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DEPARTMENT OF TRANSPORTATION

Pipeline and Hazardous Materials Safety Administration

49 CFR Parts 107, 171, 172, 173, 178 and 180

Docket No. PHMSA-2011-0140 (HM-234)

RIN 2137-AE80

Hazardous Materials: Miscellaneous Amendments Pertaining to DOT-

Specification Cylinders (RRR)

AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Pipeline and Hazardous Materials Safety Administration (PHMSA) is proposing to amend the Hazardous Materials Regulations to revise certain requirements applicable to the manufacture, use, and requalification of DOT-specification cylinders. PHMSA is taking this action in response to petitions for rulemaking submitted by stakeholders and to agency review of the compressed gas cylinders regulations. Specifically, PHMSA is proposing to incorporate by reference or update the references to several Compressed Gas Association publications, amend the filling requirements for compressed and liquefied gases, expand the use of salvage cylinders, and revise and clarify the manufacture and requalification requirements for cylinders.

DATES: Comments must be submitted by September 26, 2016. To the extent possible, PHMSA will consider late-filed comments as a final rule is developed.

ADDRESSES: You may submit comments identified by the docket number PHMSA-2011-0140 (HM-234) by any of the following methods:

Federal eRulemaking Portal: http://www.regulations.gov. Follow the instructions for submitting comments.

Fax: 1-202-493-2251.

Mail: Docket Management System; U.S. Department of Transportation, West Building, Ground Floor, Room W12-140, Routing Symbol M-30, 1200 New Jersey Avenue SE., Washington, DC 20590.

Hand Delivery: To the Docket Management System; Room W12-

140 on the ground floor of the West Building, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Instructions: All submissions must include the agency name and docket number for this NPRM at the beginning of the comment. To avoid duplication, please use only one of these four methods. All comments received will be posted without change to the Federal Docket Management System (FDMS), including any personal information.

Docket: For access to the dockets to read background documents or comments received, go to http://www.regulations.gov or DOT's Docket Operations Office (see ADDRESSES). To access and review the ASME material proposed for incorporation by reference in this rulemaking, please refer to the following Web site: http://go.asme.org/PHMSA-ASME-PRM. To access and review the CGA materials proposed for incorporation by reference in this rulemaking, please refer to the following Web site: https://www.cganet.com/customer/dot.aspx.

Privacy Act: Anyone is able to search the electronic form of any written communications and comments received into any of our dockets by the name of the individual submitting the document (or signing the document, 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 (65 FR 19477), or you may visit http://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Eileen Edmonson, Standards and Rulemaking Division, and Mark Toughiry, Mechanical Engineer, Engineering and Research Division, Pipeline and Hazardous Materials Safety Administration, U.S. Department of Transportation, 1200 New Jersey Avenue SE., Washington, DC 20590, at (202) 366-8553.

SUPPLEMENTARY INFORMATION:

1. Executive Summary

2. ANPRM Background

3. Petitions for Rulemaking and Comments Received

4. Special Permits

5. Agency Initiated Editorial Corrections

6. Section-by-Section Review

7. Regulatory Analyses and Notices

   1. Statutory/Legal Authority for This NPRM

   2. Executive Order 12866, Executive Order 13563, and DOT Regulatory Policies and Procedures

   3. Executive Order 13132

   4. Executive Order 13175

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

   6. Paperwork Reduction Act

   7. Regulation Identifier Number (RIN)

   8. Unfunded Mandates Reform Act of 1995

1. Environmental Assessment

   10. Privacy Act

   11. International Trade Analysis

1. Executive Summary

   Cylinders filled with a Class 2 hazardous material (gas) and offered for transportation must comply with various subparts of the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180). These include 49 CFR part 173, subpart G, which sets forth the requirements for preparing and packaging gases; 49 CFR part 178, subpart C, which sets forth the specifications for cylinders (i.e., how they should be constructed); and 49 CFR part 180, subpart C, which sets forth the requirements for continued qualification, maintenance, and periodic requalification of cylinders. Additionally, cylinders must meet other requirements in the HMR, such as regulations that address the modal effects on cylinders in transportation including general handling, loading, unloading, and stowage.

   PHMSA (also ``we'' or ``us''), in response to petitions for rulemaking submitted by stakeholders and an agency initiated review of the regulations, is proposing changes to the HMR, including but not limited to the following: Incorporating by reference or updating references to several Compressed Gas Association (CGA) publications; amending the filling requirements for compressed and liquefied gases; expanding the use of salvage cylinders; revising and clarifying the manufacture and requalification requirements for cylinders; and adopting a special permit (DOT-SP 14237). This NPRM is also presenting minor and miscellaneous regulatory editorial corrections. Further, PHMSA is addressing the comments received from a previous Advance Notice of Proposed Rulemaking (ANPRM; 77 FR 31551), and proposing additional revisions that have been requested in petitions received since the ANPRM's 2012 publication. These proposed revisions intend to reduce regulatory burdens while maintaining or enhancing the existing level of safety. In this NPRM, PHMSA is responding to 20 petitions for rulemaking submitted by stakeholders.

2. ANPRM Background

   On May 29, 2012 77 FR 31551, PHMSA published an ANPRM to obtain public comment from those likely to be affected by the possible incorporation of 10 petitions for rulemaking and 3 special permits into the HMR. These include cylinder manufacturers (approximately 568 companies); cylinder requalifiers; independent

   Page 48979

   inspection agencies; commercial establishments that own and use DOT-

   specification cylinders and UN pressure receptacles; and individuals who export non-UN/ISO compressed gas cylinders. Incorporating these petitions for rulemaking and special permits would update and expand the use of currently authorized industry consensus standards; revise the construction, marking, and testing requirements of DOT-4 series cylinders; clarify the filling requirements for cylinders; discuss the handling of cylinders used in fire suppression system; and revise the requalification and condemnation requirements for cylinders.

   The ANPRM comment period closed on August 27, 2012. PHMSA received comments from 13 stakeholders, including compressed gas and/or cylinder manufacturers, cylinder testers, and trade associations representing the compressed gas industry or shippers of hazardous materials. Most comments either answered questions PHMSA posed in the ANPRM or responded to multiple petitions and/or special permits. Regarding the petitions, the comments received were mostly supporting for all but one--P-1515. PHMSA received four comments regarding special permits, and all supported their adoption into the HMR. A list of the commenters, along with the related Docket ID Number, is shown in Table 1 below:

   Table 1--ANPRM Commenters and Associated Comments Docket Nos.

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   Company Docket ID No.

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   Air Products and Chemicals, Inc.. PHMSA-2011-0140-0004

   PHMSA-2011-0140-0008

   PHMSA-2011-0140-0018

   Bancroft Hinchley................ PHMSA-2011-0149-0024

   Barlen and Associates, Inc....... PHMSA-2011-0140-0019

   City Carbonic, LLC............... PHMSA-2011-0140-0029

   Compressed Gas Association....... PHMSA-2011-0140-0005

   PHMSA-2011-0140-0012

   PHMSA-2011-0140-0013

   PHMSA-2011-0140-0020

   Council on Safe Transportation of PHMSA-2011-0140-0026

   Hazardous Articles, Inc.

   CTC Certified Training........... PHMSA-2011-0140-0001

   PHMSA-2011-0140-0023

   PHMSA-2011-0140-0030

   HMT Associates................... PHMSA-2011-0140-0002

   PHMSA-2011-0140-0021

   Hydro-Test Products, Inc......... PHMSA-2011-0140-0017

   Manchester Tank.................. PHMSA-2011-0140-0016

   Norris Cylinder.................. PHMSA-2011-0140-0025

   SodaStream USA, Inc.............. PHMSA-2011-0140-0027

   Worthington Cylinder Corporation. PHMSA-2011-0140-0028

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3. Petitions for Rulemaking and Comments Received

   Table 2 lists the petitions included in the docket for this proceeding. This NPRM addresses 20 total petitions. Ten petitions are associated with the ANPRM, and 10 additional petitions have been included since its publication. This table provides the petition number, the petitioner's name, the docket number on www.regulations.gov, a brief summary of the petitioner's requests, the affected sections, and whether or not we are proposing to adopt the petition:

   Table 2--Petition Summary

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   Proposed

   Petition No. Petitioner Docket No. Summary affected Proposing to

   sections adopt?

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   P-1499........... Compressed Gas PHMSA-2007-28485........ Replace the Sec. Sec. Yes.

   Association. incorporated 171.7; 172.102

   by reference (SP 338);

   (IBR) Seventh 173.3(d)(9);

   Edition of the 173.198(a);

   CGA C-6 180.205(f)(1);

   Standards for 180.209(c),

   Visual (b)(1)(iii),

   Inspection of (d), (f), (g),

   Steel (m);

   Compressed Gas 180.211(d)(1)(

   Cylinders with ii);

   the revised 180.411(b);

   Tenth Edition 180.510(c).

   and update the

   appropriate

   references

   throughout the

   HMR.

   P-1501........... Compressed Gas PHMSA-2007-28759........ Revise the Sec. Sec. Yes, in part.

   Association. specification 178.50,

   requirements 178.51,

   for 4B, 4BA, 178.61, 178.68.

   4BW, and 4E

   cylinders to

   provide

   clarity.

   P-1515........... Certified PHMSA-2008-0101......... Adopt changes Sec. Sec. Yes, except

   Training to the 180.203, those changes

   Company. requalificatio 180.205, not necessary

   n process 180.207, because of IBR

   designed to 180.209, of CGA C-1

   clarify the 180.211, under P-1626.

   regulations in 180.212,

   the event CGA 180.213,

   Standard C-1, 180.215,

   Methods of appendix C to

   Pressure part 180,

   Testing appendix E to

   Compressed Gas part 180.

   Cylinders, is

   not

   incorporated.

   Page 48980

   P-1521........... Compressed Gas PHMSA-2008-0152......... Allow the use Sec. Yes.

   Association. of labels 172.400a(a)(1)

   described in (i).

   CGA C-7-2004

   on a cylinder

   contained in

   an overpack.

   P-1538........... The Wicks Group, PHMSA-2009-0138......... Allow Sec. Sec. Sec. No.

   representing 173.306(a)(1) 171.8,

   Jetboil Inc. to permit 173.306(a)(1).

   camping stove

   cylinders

   containing

   liquefied

   petroleum gas

   in amounts

   less than four

   (4) ounces to

   be shipped as

   consumer

   commodity (ORM-

   D). Define

   ``capacity''

   in Sec.

   171.8.

   P-1539........... Matheson Tri-Gas PHMSA-2009-0140......... Allow DOT 3A, Sec. No.

   3AA, 3AL 180.209(a).

   cylinders in

   Division 2.2

   Services to be

   retested every

   15 years.

   Allow DOT 3A,

   3AA, and 3AL

   cylinders

   packaged with

   Division 2.1

   materials to

   be requalified

   every 10

   years..

   P-1540........... Compressed Gas PHMSA-2009-0146......... Require newly Sec. Yes.

   Association. manufactured 178.35(f).

   DOT 4B, 4BA,

   4BW, and 4E

   cylinders to

   be marked with

   the mass

   weight, tare

   weight, and

   water capacity.

   P-1546........... GSI Training PHMSA-2009-0250......... Allow cylinders Sec. Yes.

   Services, Inc. used as a 173.309(a).

   component of a

   fixed fire

   suppression

   system to be

   transported

   under the

   exceptions

   applicable to

   fire

   extinguishers.

   P-1560........... Air Products and PHMSA-2010-0176......... Modify the Sec. No. Addressed

   Chemicals, Inc. maximum 173.304a(a)(2). by revisions

   permitted made under

   filling rulemaking HM-

   densities for 233F 81 FR

   carbon dioxide 3635.

   and nitrous

   oxide to

   include 70.3%,

   73.2%, and

   74.5% in DOT

   3A, 3AA, 3AX,

   3AAX, and 3T

   cylinders.

   P-1563........... Regulatory PHMSA-2010-0208......... Authorize an Sec. 173.301 Uncertain. We

   Affairs ``overpack'' (a)(9). are asking for

   Management as a strong further

   Center--3M outer package comment.

   Package for cylinders

   Engineering, listed in the

   Global section,

   Dangerous Goods. except

   aerosols

   ``2P'' and

   ``2Q,'' marked

   with the

   phrase ``inner

   packagings

   conform to the

   prescribed

   specifications

   ''.

   P-1572........... Barlen and PHMSA-2011-0017......... Revise the Sec. Sec. Yes, in part.

   Associates, filling ratio 173.301(g)(1)(

   Inc. for liquefied ii) and

   compressed 173.312.

   gases in MEGCs

   consistent

   with Packing

   Instruction

   (P200) of the

   United Nations

   (UN)--Model

   Regulations

   (17th ed.

   2011), as

   specified in

   Sec.

   173.304b; and

   prohibit

   liquefied

   compressed

   gases in

   manifolded DOT

   cylinders from

   exceeding the

   filling

   densities

   specified in

   Sec.

   173.304a(a)(2).

   P-1580........... HMT Associates.. PHMSA-2011-0123......... Require the Sec. Sec. Yes.

   burst pressure 173.301(f)(4),

   of the rupture 173.302(f)(2),

   disc on a 173.304(f)(2).

   cylinder

   ``shall not

   exceed 80% of

   the minimum

   cylinder burst

   pressure and

   shall not be

   less than 105%

   of the

   cylinder test

   pressure''.

   P-1582........... Water Systems PHMSA-2011-0135......... Revise the Sec. Yes.

   Council. limited 173.306(g).

   quantity

   exception for

   water pump

   system tanks

   to authorize

   transport of

   tanks

   manufactured

   to American

   National

   Standards

   Institute's

   Water Systems

   Council

   Standard PST-

   2000-2005(2009

   ).

   Page 48981

   P-1592........... Compressed Gas PHMSA-2012-0173......... IBR CGA S-1.1, Sec. Sec. Yes.

   Association. 2011 Pressure 173.301(c),

   Relief Device (f) and (g),

   Standards, 173.304a(e),

   Part 1, 178.75(f).

   Cylinder for

   Compressed

   Gas,

   Fourteenth

   Edition.

   P-1596........... Chemically PHMSA-2012-0200......... Add Class 4 and Sec. Yes.

   Speaking, LLC. Class 5 173.3(d)(2).

   hazardous

   materials to

   the hazard

   classes in an

   authorized

   salvage

   cylinders.

   P-1622........... Worthington PHMSA-2013-0210......... Restrict the Sec. Sec. Yes.

   Cylinders internal 173.304a and

   Corporation. volume of 173.304a(a)(3).

   hazardous

   materials

   shipped in a

   DOT-

   specification

   39 cylinder to

   not exceed 75

   cubic inches.

   P-1626........... Compressed Gas PHMSA-2013-0265......... IBR CGA C-1- Sec. Sec. Yes.

   Association. 2009, Methods 171.7, 178.36,

   for Pressure 178.37,

   Testing 178.38,

   Compressed Gas 178.39,

   Cylinders, 178.42,

   Tenth Edition 178.44,

   (C-1, 2009) as 178.45,

   a reference in 178.46,

   49 CFR, and 178.47,

   provide for 178.50,

   specific 178.51,

   language for 178.53,

   sections 178.55,

   affected. 178.56,

   178.57,

   178.58,

   178.59,

   178.60,

   178.61,

   178.65,

   178.68,

   180.205,

   180.209.

   P-1628........... Compressed Gas PHMSA-2013-0278......... IBR CGA C-3- Sec. Sec. Yes.

   Association. 2005, 171.7, 178.47,

   Reaffirmed 178.50,

   2011, 178.51,

   Standards for 178.53,

   Welding on 178.55,

   Thin-Walled, 178.56,

   Steel 178.57,

   Cylinders, 178.58,

   Seventh 178.59,

   Edition. 178.60,

   178.61,

   178.65,

   178.68,

   180.211.

   P-1629........... Compressed Gas PHMSA-2014-0012......... IBR CGA C-14- Sec. Sec. Yes.

   Association. 2005, 171.7,

   Reaffirmed 173.301,

   2010, 173.323.

   Procedures for

   Fire Testing

   of DOT

   Cylinder

   Pressure

   Relief Device

   Systems,

   Fourth

   Edition, as a

   reference in

   49 CFR.

   P-1630........... Compressed Gas PHMSA-2014-0027......... Add the term Sec. Sec. Yes.

   Association. ``recondition' 180.203,

   ' for DOT-4L 180.211(c),

   welded and 180.211(e).

   insulated

   cylinders and

   revise

   language to

   clarify when a

   hydrostatic

   test must be

   performed on

   the inner

   containment

   vessel after

   the DOT-4L

   welded

   insulated

   cylinder has

   undergone

   repair.

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   P-1499

   The CGA submitted P-1499 requesting that PHMSA replace the currently incorporated by reference C-6 Standards for Visual Inspection of Steel Compressed Gas Cylinders, Seventh Edition with the revised Tenth Edition and update the appropriate references throughout the HMR. The Tenth Edition provides enhanced guidance for cylinder requalifiers--including guidance on the inspection of Multiple-Element Gas Containers (MEGCs) and the requirements for thread inspection for cylinders used in corrosive gas service--and clarifies maximum allowable depths and measuring techniques for various types of corrosion.

   PHMSA identified approximately 5,000 companies that would be subject to this standard, with the majority being classified as small businesses using the Small Business Administration (SBA) size standards (1.0% of the prescribed test pressure of any cylinder tested that day.'' This interpretation attempts to declare a test invalid due to a 2 psi drop in pressure at 3000 psi. The pressure indicating device has already been defined as having a 1% resolution and 1% accuracy. According to the definition of the device, it can deviate by 30 psi at 3000 psi (30 psi = 1% of 3000 psi). This interpretation violates the definition of the device as stated in these two paragraphs.

   Furthermore, many special permits, such as DOT-SP 10915 and 10945, recognize that different materials (such as the carbon-fiber wrapped, aluminum lined cylinders referenced in these special permits) take even longer than 30 seconds to completely deform under the load of test pressure, and therefore require a hold time of 60 seconds. According to this interpretation, these special permits would require a hold time of 60 seconds (or longer), until the cylinder completed its expansion, and then an additional 60 seconds of hold time, wherein the pressure could not drop by even 2 psi. This, obviously, is not the intention of these special permits when they state, ``. . . for a minimum test time of one minute.''

   Industry standard CGA C-1, Seventh Edition 1996, ``Methods for Hydrostatic Testing of Compressed Gas Cylinders,'' in paragraph 4.4(g) states, ``when the desired

   Page 48984

   value is reached, stop the pressurization and hold for 30 seconds.'' And, ``the expansion and pressure should remain stable during the entire 30 seconds. If either the pressure or expansion do not stabilize within 1%, see 4.5 Troubleshooting.'' Thus, the 30-second hold begins when the pump stops, and deviation during the hold time is allowed up to the defined accuracy of the device, that is, 1% of the test pressure, and 1% of the total expansion.

   Manufacturers of hydrostatic test equipment specify in their manuals and the software controlling automated equipment that the 30-second hold time begins when the test pressure is reached and the pump is turned off.

   The CTC further states: ``This interpretation declares virtually every test performed on cylinders in the past century to be invalid, since every cylinder tested (as well as the hoses on the machine) will continue to expand after the pump is stopped. Therefore the pressure will drop. The only issue is whether or not the device is capable of detecting such a minute drop in pressure.'' The CTC believes this interpretation is based on two misunderstandings:

   1. Closed loop hydraulics vs. open system. In a closed loop hydraulic system (such as the controls on an aircraft), any drop in pressure is unacceptable. This does not apply to an open system where the pressure will drop (e.g., a cylinder expanding during a test).

   2. Higher precision digital devices vs. analog devices. There has always been a slight drop in pressure during the hold time. On an analog device, it was not visible. It is now visible on a digital device, but that does not simply invalidate the test.

      PHMSA agrees with the CTC that the language in Reference No. 05-

      0087 is misleading and believes the IBR of CGA C-1 into Sec. 180.205, in conjunction with additional changes to the regulations proposed consistent with petition P-1626, will resolve any issue the CTC may have with this letter of interpretation. We invite comment on this conclusion. PHMSA also plans to retract Reference No. 05-0087.

      P-1521

      The CGA submitted P-1521 requesting that PHMSA modify the provision in Sec. 172.400a(a)(1)(i) to remove the limitation that only allows the use of the neckring markings if a cylinder is not overpacked. The petition would still require the overpack to display the labels in conformance with 49 CFR part 172, subpart E.

      The HMR permit the use of a neckring marking, under certain conditions, in conformance with the CGA C-7, Guide to Preparation of Precautionary Labeling and Marking of Compressed Gas Containers, Appendix A, Eighth Edition (2004) under Sec. 172.400a. This neckring marking identifies the contents of a cylinder by displaying the proper shipping name, the UN identification number, and the hazard class or division label within a single marking. Section 172.400a(a)(1) permits the use of this marking in lieu of required labels on a Dewar flask meeting the requirements in Sec. 173.320 or a cylinder containing Division 2.1, 2.2, and 2.3 material that is not overpacked. This requirement should provide flexibility in hazard communication for cylinders, especially small cylinders.

      The marking prescribed in appendix A to CGA C-7 provides useful information in a clear and consistent manner, and its widespread use on cylinders has enhanced its recognition. CGA's proposed change would provide greater flexibility for shipments of overpacked cylinders while ensuring adequate hazard communication. If cylinders are contained in an overpack, the overpack must display the appropriate markings and labels.

      PHMSA identified approximately 86 entities engaged in Industrial Gas Manufacturing, of which 74 are classed as small entities ( What is the average total cost per cylinder to complete these markings (i.e., is an estimated cost of $0.10 per character for new markings accurate)?

      What is the estimated quantity of newly manufactured 4B, 4BA, 4BW and 4E cylinders each year? Furthermore, how many of these cylinders already display tare weight and water capacity markings in compliance with NFPA 58 or other codes?

      How many manufacturers of the cylinders mentioned above are considered small businesses by the SBA?

      PHMSA sought to identify: (1) The frequency of which the mass weight or tare weight, and water capacity markings are already permissively applied to cylinders, (2) the costs associated with applying these marks, (3) the safety benefits associated with the additional markings, and (4) the alternate methods or safeguards against overfilling of cylinders currently being implemented.

      Air Products and Chemicals supports the petition with no additional comments. The CGA supports the inclusions of tare weight, mass weight, and water capacity requirements on newly constructed DOT 4B, 4BA, 4BW, and 4E specification cylinders at the time of manufacture but does not support--and strongly disagrees with--PHMSA's consideration of modifying Sec. 178.35 to require all DOT-specification cylinders suitable for the transport of liquefied gases to be marked with the cylinder's tare weight and water capacity. The CGA also believes that the 49 CFR must further clarify that no cylinder must be filled with a liquefied gas unless a mass or tare weight is marked on the cylinder, providing the following justification:

      At the time of manufacture, the manufacturer would not know whether the DOT 3 series cylinders are or are not be used in a liquefied gas service;

      Marking all cylinders, as suggested by DOT, would include every cylinder manufactured in conformance with the specifications set forth in the HMR, which would therefore require cylinders that have been designed and manufactured for a specific permanent gas application be marked for tare weight and water capacity just because the cylinder could be used (at some time) for liquefiable gas;

      There would be instances on small 3-series cylinders where the additional marking would not fit onto the dome of the cylinder; and

      The economic impact estimated for marking all cylinders is significantly greater than the estimates submitted by PHMSA.

      Manchester Tank expresses concern that numerous variations in stamped weights could cause confusion in the field among fillers. They state that adding mass weight stamping to a cylinder that already has tare weight stamped could lead to incorrect filling if the wrong figure is used. They ask PHMSA for specific clarification of the language to assign the duty to mark tare weight to the valve installer and indicate that there are many cylinders that are not valved by the manufacturer, further declared that those cylinders can be marked correctly with mass weight--but not with tare weight, since the weight of the appurtenance may not be known to the manufacturer of the vessel. In addition, Manchester Tank notes that available space for stamping is limited on some vessels and increased stamping will not allow significant space for retest marking information.

      In this NPRM, PHMSA is proposing to revise Sec. 178.35(f) to require that tare weight or mass weight, and water capacity be marked on certain DOT 4-series specification cylinders used for the transport of liquefied gases as petitioned by the CGA. We stress that while cylinder markings are important to ensure the safe filling of liquefied compressed gas, they do not take the place of adequate personnel training, procedures to ensure proper filling, and continued requalification and maintenance of cylinders in preventing incidents. PHMSA seeks additional comment on expanding this marking requirement to other DOT-specification cylinders and the costs and benefits as well as the safety implications of doing so.

      P-1546

      GSI Training Services submitted P-1546 requesting that PHMSA allow cylinders that form a component of fire suppression systems to use the proper shipping name ``Fire extinguishers'' when offered for transportation. The Hazardous Materials Table (HMT) in Sec. 172.101 provides a shipping description for cylinders used as fire extinguishers (i.e., ``UN1044, Fire extinguishers, 2.2'') and references Sec. 173.309 for exceptions and non-bulk packaging requirements. Fire extinguishers charged with a limited quantity of compressed gas are excepted from labeling, placarding, and shipping paper requirements under certain conditions if the cylinder is packaged and offered for transportation in conformance with Sec. 173.309.\3\ Additionally, fire extinguishers filled in conformance with the requirements of Sec. 173.309 may use non-specification cylinders (i.e., cylinders not manufactured to specifications in part 178). Part 180 also provides special requirements for cylinders used as fire extinguishers (e.g., Sec. 180.209(j) includes different requalification intervals).

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      \3\ Note that the format of Sec. 173.309 was changed under a final rule published January 7, 2013 (HM-215K; 78 FR 1101) such that the exceptions for limited quantities has been relocated to paragraph (d) of Sec. 173.309.

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      PHMSA has written several letters of clarification regarding the applicability of Sec. 173.309 to fire extinguishers. Notably on March 9, 2005, PHMSA wrote a letter (Reference No. 04-0202) to Safecraft Safety Equipment regarding non-specification stainless steel cylinders used as a component in a fire suppression system for installation in vehicles and stated that the cylinders used in the fire suppression system appeared to meet the requirements of Sec. 173.309. PHMSA issued another letter (Reference No. 06-0101) on May 30, 2008, to Buckeye Fire Equipment stating that the company could not use the shipping name ``Fire extinguishers'' for their cylinders, which served as a component of a kitchen fire suppression system, and must use the proper shipping name that best describes the material contained in the cylinder since these cylinders were not equipped to function as fire extinguishers. This latter clarification effectively required

      Page 48987

      cylinders that are part of a fixed fire suppression system to meet an appropriate DOT-specification.

      In response to Reference No. 06-0101, GSI Training Services submitted a petition for rulemaking requesting PHMSA to allow cylinders that form a component of fire suppression systems to use the proper shipping name ``Fire extinguishers'' when offered for transportation, stating that: (1) At least one company manufactured over 39,000 non-

      specification cylinders for use in fire suppression systems based on the information provided in the March 9, 2005 letter; and (2) the May 30, 2008 clarification effectively placed this company out of compliance. GSI Training Services further suggests that cylinders comprising a component of a fixed fire suppression system will provide an equal or greater level of safety than portable fire extinguishers since cylinders in fire suppression systems are typically installed in buildings where they are protected from damage and not handled on a regular basis.

      In this NPRM, PHMSA is proposing to revise the Sec. 173.309 introductory text to include cylinders used as part of a fire suppression system as a cylinder type authorized for transport in accordance with the HMT entry for fire extinguishers. The controls detailed in Sec. 173.309 provide an acceptable level of safety regardless of whether the cylinder is equipped for use as a handheld fire extinguisher or as a component of a fixed fire suppression system.

      P-1563

      3M Corporation submitted P-1563 requesting that PHMSA address the regulatory confusion between marking requirements for overpacks in Sec. 173.25 and outside packages for certain thin-walled cylinders specified in Sec. 173.301(a)(9). The petitioner notes that the differing marking requirements in Sec. Sec. 173.25 and 173.301(a)(9) create confusion and make training difficult. This petition requests modification of the HMR to permit materials packaged in conformance with Sec. 173.301(a)(9)--except aerosols ``2P'' and ``2Q''--to display the ``OVERPACK'' marking described in Sec. 173.25, in lieu of the current requirement for ``an indication that the inner packaging conforms to prescribed specifications.''

      In accordance with Sec. 173.301(a)(9), DOT-specification 2P, 2Q, 3E, 3HT, spherical 4BA, 4D, 4DA, 4DS, and 39 cylinders must be packed in strong non-bulk outer packagings. This configuration meets the definition of a combination package as indicated in paragraph (a)(9) and further, as defined in Sec. 171.8 of the HMR. Paragraph (a)(9) requires the outside of this combination packaging to be marked with an indication that the inner packagings conform to the prescribed specifications. The completed combination package is subject to marking and labeling, as appropriate; however, the inner packagings do not have to be marked or labeled. These combination packages cannot also then be considered ``overpacks.'' For each completed package bearing required marking(s) and label(s) that is placed in an overpack, for consolidation or ease of handling, the overpack must also display the appropriate marking(s) and label(s) unless visible through the overpack see Sec. 173.25(a)(2). The ``OVERPACK'' mark must be applied when specification packagings are required by the HMR to communicate that the overpack contains specification packagings in conformance with the HMR.

      The marking ``inside (inner) packages comply with the prescribed specifications'' for overpacks in Sec. 173.25 was changed in 2004 to ``OVERPACK'' in an effort to better align with global overpack requirements. The 3M Corporation accurately states that prior to 2004 both the overpack requirements in Sec. 173.25 and the requirement in Sec. 173.301(a)(9) to package certain DOT-specification cylinders in strong, non-bulk outer packagings used very similar language intended to inform package handlers that although not visible, the inner packages contained specification packagings that conformed to appropriate DOT or UN standards.

      PHMSA recognizes that differing marking requirements in Sec. Sec. 173.25 and 173.301(a)(9) to communicate the same intended meaning may be causing confusion without enhancing safety. In order to address the petition and provide for greater clarity, PHMSA is proposing to revise Sec. 173.301(a)(9) to authorize use of the ``OVERPACK'' marking as specified in Sec. 173.25(a)(3) as a method to satisfy the current requirement in paragraph (a)(1) to mark the completed package with an indication that the inner packagings conform to prescribed specifications for the listed cylinders. We agree with 3M that the issue is more complex for 2P and 2Q containers as specified in Sec. Sec. 173.304, 173.305, and 173.306 and, therefore, are not including 2P and 2Q in the allowance for the ``OVERPACK'' marking. The revision will also include instructional language that the combination package is not to be considered an ``overpack.'' PHMSA welcomes comments from affected entities regarding the following: potential consequences, safety and economic impacts, current level of difficulty and unnecessary confusion, need for change, quantity of shipments per year to be impacted, etc.

      P-1572

      Barlen and Associates submitted P-1572 requesting that PHMSA explicitly state in Sec. 173.312 that for liquefied compressed gases in Multiple-Element Gas Containers (MEGCs), the filling density of each pressure receptacle must not exceed the values contained in Packing Instruction P200 of the UN Model Regulations, as specified in Sec. 173.304b, and the contents of each DOT-specification cylinder cannot exceed the densities specified in Sec. 173.304a(a)(2).\4\

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

      \4\ Note that the petition specifically referenced the 17th ed. of the UN Model Regulations, however, we will propose a change that references the edition currently incorporated by reference in Sec. 171.7 because we biennially update the edition for harmonization with international standards.

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

      Requirements for shipping MEGCs are specified in Sec. 173.312. Specifically, Sec. 173.312(b) details the filling requirements for MEGCs and states,'' a MEGC may not be filled to a pressure greater than the lowest marked working pressure of any pressure receptacle and a MEGC may not be filled above its marked maximum permissible gross mass.'' The requirement that each pressure receptacle contained in the MEGC may not be filled above the working pressure of the lowest marked working pressure of any pressure receptacle is clear for permanent (non-liquefied compressed) gases, which are generally filled by pressure; however, Sec. 173.312(b) does not contain a corresponding requirement addressing pressure receptacles containing a liquefied compressed gas, which are most often filled by weight. This lack of specificity for MEGCs containing liquefied compressed gas has led to some confusion on methods for their proper filling. Therefore, in this NPRM, we propose to specify the filling ratio requirements for pressure receptacles.

      PHMSA does not anticipate this provision will impose any new burden, as this proposal would only emphasize an important safety requirement already stated in Sec. 173.304a for DOT-specification cylinders and Sec. 173.304b for UN pressure receptacles. PHMSA invites comments from affected entities regarding the following: Safety and economic impacts, level of difficulty and unnecessary confusion, need for change, etc.

      Page 48988

      P-1580

      HMT Associates submitted P-1580 requesting that PHMSA revise Sec. Sec. 173.302(f)(2) and 173.304(f)(2) to require that the burst pressure of a rupture disc coincide with CGA S-1.1 for DOT 39 cylinders offered for transportation after October 1, 2008; other DOT-

      specification cylinders with the first requalification due after October 1, 2008; and UN pressure receptacles prior to initial use. Specifically, as prescribed in 4.2.2 of CGA S-1.1, the required burst pressure of the rupture disc ``shall not exceed 80% of the minimum cylinder burst pressure and shall not be less than 105% of the cylinder test pressure.''

      Section 173.301(f) states that a cylinder filled with a compressed gas and offered for transportation ``must be equipped with one or more pressure relief devices (PRDs) sized and selected as to type, location and quantity and tested in conformance with CGA S-1.1 Pressure Relief Device Standards--Part 1--Cylinders for Compressed Gases, Fourteenth Edition (2005) and CGA S-7 Method for Selecting Pressure Relief Devices for Compressed Gas Mixtures in Cylinders (2005).'' Sections 172.302(f)(2) and 172.304(f)(2) specify that the rated burst pressure of a rupture disc for DOT 3A, 3AA, 3AL, 3E, and 39 cylinders, as well as that for UN ISO 9809-1, ISO 9809-2, ISO 9809-3, and ISO 7866 cylinders containing oxygen, compressed; compressed gas, oxidizing, n.o.s.; or nitrogen trifluoride, must be 100 percent of the cylinder minimum test pressure with a tolerance of `plus zero' to minus 10 percent.

      In response to PHMSA's NPRM entitled ``Hazardous Materials: Miscellaneous Amendments'' published on September 29, 2010 75 FR 60017 under Docket No. PHMSA-2009-0151 (HM-218F), HMT Associates submitted a late-filed comment that identified a potential discrepancy between the HMR and CGA S-1.1. Specifically, this commenter stated the HMR have different PRD settings than CGA S-1.1 for DOT 39 cylinders that make it virtually impossible to comply with both the HMR and CGA S-1.1. Sections 173.302(f)(2) and 173.304(f)(2) require the rated burst pressure of a rupture disc for DOT 3A, 3AA, 3AL, 3E, and DOT 39 cylinders to be 100 percent of the cylinder minimum test pressure with a tolerance of `plus zero' to minus 10 percent, whereas section 4.2.2 of CGA S-1.1 requires the rated burst pressure of the rupture disc on DOT 39 cylinders to be not less than 105 percent of the cylinder test pressure.

      In this NPRM, PHMSA proposes to revise Sec. 173.301(f) as it applies to DOT 39 cylinders to alleviate any confusion and conflict between the PRD requirements in Sec. 173.301(f) and those in Sec. Sec. 173.302(f)(2) and 173.304(f)(2) with respect to minimum burst pressure of pressure relief devices on a DOT 39 cylinder used for the transport of compressed and liquified oxidizing gases by air. PHMSA notes that the revision made to Sec. 173.301(f) was based on option 2 presented in HMT Associates comment to rulemaking HM-218F and submitted as petition P-1580. PHMSA requests comments from the compressed gas industry regarding this course of action.

      P-1582

      Water Systems Council submitted P-1582 requesting that PHMSA revise Sec. 173.306(g), which provides a limited quantity exception for water pump system tanks, by permitting tanks manufactured to American National Standards Institute (ANSI) and Water Systems Council (WSC) standard PST-2000-2005(2009) to be authorized for transport.

      ANSI and WSC standard PST-2000-2005 is an industry standard that prescribes minimum performance and construction requirements for pressurized storage tanks for service in water well systems with a maximum factory pre-charge pressure of 40 psig (280 kPa), to be operated in ambient air temperatures up to 120emsp14degF (49 degC), with maximum working pressures not less than 75 psig (520 kPa) and not greater than 150 psig (1,000 kPa) and tank volumes not exceeding 120 gallons (450 L). The standard was developed by a group of WSC members comprised of leading U.S. manufacturers of pressurized water storage tanks for water wells to define and promote--through voluntary written standards--minimum performance and construction requirements for pressurized water storage tanks for service in water well systems. Incorporating the standard into the HMR will provide minimum requirements for pressurized water storage tanks for water wells that provide at least an equivalent level of safety as currently provided in the HMR.

      PHMSA identified 38 U.S. based manufacturers or distributors of water pump system tanks, most of which would be classified as a small business using SBA size standards ( Added section to the testing criteria to employ the use of macro etch samples in lieu of weld guided bend test and weld tensile testing when the cylinder size would not permit securing of proper size specimens.

      Clarified the weld bend testing procedure, weld bend testing tooling, and proper clearances that are required in the tooling.

      Clarified definitions for the welding procedure qualification and the welding operator weld qualification.

      Added tolerance section to C-3-2005, Reaffirmed 2011 that indicates the plus and minus tolerances when a specific dimensional tolerance is indicated in the publication.

      Added drawings to the C-3-2005, Reaffirmed 2011 illustrating different weld joint designs.

      Reviewed C-3-2005, Reaffirmed 2011 for conditional wording and revised it for enforceable wording.

      PHMSA identified approximately 5,000 companies that would be subject to this standard, with the majority being classified as small businesses using SBA size standards ( Permitted the use of an alternate lading. If the intended lading would present an increased safety hazard during the test procedure (such as the use of poisonous or flammable gas), the cylinder may be charged with a typical liquefied or non-liquefied gas. Gases with essentially similar physical properties may be classified as typical.

      Added the Bonfire Test Method to the publication. This permitted the Board of Explosives (BOE) test method to be used to qualify pressure relief device systems. The Bonfire Test Method was successfully used to qualify pressure relief device systems for decades.

      Clarified what information is to be recorded before and during the actual test.

      Increased the water capacity of a cylinder that can be fire tested from 500 lb. water capacity to 1000 lbs. water capacity to permit a test method for all 4 series cylinders.

      Reviewed C-14-2005, Reaffirmed 2010 for conditional wording and modified it to replace conditional wording with enforceable wording, wherever appropriate.

      PHMSA identified approximately 5,000 companies that would be subject to this standard, with the majority being classified as small businesses using SBA size standards ( Replace the currently incorporated Seventh Edition of the CGA's publication C-6 Standards for Visual Inspection of Steel Compressed Gas Cylinders with the revised Tenth Edition and update the appropriate references throughout the HMR.

      Revise the manufacturing requirements for certain DOT-4 series cylinders.

      Revise the requirements for the requalification of DOT-

      specification cylinders by pressure testing found in 49 CFR part 180, subpart C.

      Allow the use of the labels described in the Eighth Edition of CGA's publication C-7 Guide to the Preparation of Precautionary Labeling and Marking of Compressed Gas Containers (currently IBR in the HMR) appendix A on cylinders contained in overpacks.

      Require manufacturers to mark newly manufactured cylinders suitable for the transport of liquefied compressed gas with the mass weight or tare weight, and water capacity.

      Allow non-specification cylinders used in a fixed fire suppression system to be transported under the same exceptions as those provided for fire extinguishers.

      Permit use of the OVERPACK marking for cylinders packed in conformance with Sec. 173.301(a)(9).

      Clarify filling limits for a liquefied compressed gas in a manifold or a multiple element gas container (MEGC).

      Clarify the requirements for filling non-specification cylinders for export or use on board a vessel.

      Add requirements for DOT-specification cylinders used to transport adsorbed gases.

   2. Alternatives Considered

      Alternative (1): Do nothing. Our goal is to update, clarify, and provide relief from certain existing regulatory requirements to promote safer transportation practices, eliminate unnecessary regulatory requirements, and facilitate international commerce. We rejected the do-nothing alternative.

      Alternative (2): Preferred choice. With this alternative, PHMSA will publish an NPRM seeking public comment on the issues raised in 20 petitions for rulemaking and the incorporation of one special permit; review the comments received on the amendments described in the ANPRM and their potential economic and safety implications; and use these comments to craft more specific proposals that are published in this NPRM. This is the selected alternative.

      Page 48999

   3. Environmental Impacts

      Hazardous materials are substances that may pose a threat to public safety or the environment during transportation because of their physical, chemical, or nuclear properties. The hazardous materials regulatory system is a risk management system that is prevention-

      oriented and focused on identifying a safety hazard and reducing the probability and quantity of a hazardous material release. Hazardous materials are categorized by hazard analysis and experience into hazard classes and packing groups. The regulations require each shipper to classify a material in accordance with these hazard classes and packing groups. The process of classifying a hazardous material is itself a form of hazard analysis. Further, the regulations require the shipper to communicate a material's hazards through the use of hazard class, packing group, and proper shipping name on the shipping paper and the use of labels on packages and placards on transport vehicles. Thus, the shipping paper, labels, and placards communicate the most significant findings of the shipper's hazard analysis. A hazardous material is assigned to one of three packing groups based upon its degree of hazard, from a high hazard material (Packing Group I) to a low hazard material (Packing Group III). The quality, damage resistance, and performance standards of the packaging in each packing group are appropriate for the hazards of the material transported.

      Under the HMR, hazardous materials are transported by aircraft, vessel, rail, and highway. The potential for environmental damage or contamination exists when packages of hazardous materials are involved in accidents or en route incidents resulting from cargo shifts, valve failures, package failures, loading, unloading, collisions, handling problems, or deliberate sabotage. The release of hazardous materials can cause the loss of ecological resources (e.g., wildlife habitats) and the contamination of air, aquatic environments, and soil. Contamination of soil can lead to the contamination of ground water. Compliance with the HMR substantially reduces the possibility of accidental release of hazardous materials.

      It is anticipated that the petitions and special permits discussed in this NPRM if adopted in a future rulemaking, would have minimal, if any, environmental consequences.

   4. Agencies Consulted

      Occupational Safety and Health Administration

      National Institute of Standards and Technology

      U.S. Environmental Protection Agency

   5. Conclusion

      PHMSA has conducted a technical review of the amendments discussed in this NPRM and determined that the amendments considered would provide protection against the release of hazardous materials based on sound scientific methods and would not result in unusual stresses on the cylinder or adversely impact human health or the environment. PHMSA welcomes any data or information related to environmental impacts, both positive and negative, that may result from a future rulemaking addressing the issues discussed in this NPRM.

      10. Privacy Act

          In accordance with 5 U.S.C. 553(c), DOT solicits comments from the public to better inform its rulemaking process. DOT posts these comments, without edit, including any personal information the commenter provides, to www.regulations.gov, as described in the system of records notice (DOT/ALL-14 FDMS), which can be reviewed at www.dot.gov/privacy.

      11. International Trade Analysis

          The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal agencies from establishing any standards or engaging in related activities that create unnecessary obstacles to the foreign commerce of the United States. Pursuant to these Acts, the establishment of standards is not considered an unnecessary obstacle to the foreign commerce of the United States, so long as the standards have a legitimate domestic objective, such as the protection of safety, and do not operate in a manner that excludes imports that meet this objective. The statute also requires consideration of international standards and, where appropriate, that they be the basis for U.S. standards. PHMSA notes the purpose is to ensure the safety of the American public and has assessed the effects of this NPRM to ensure that it does not exclude imports that meet this objective. As a result, this NPRM is not considered as creating an unnecessary obstacle to foreign commerce.

          List of Subjects

          49 CFR Part 107

          Administrative practice and procedure, Hazardous materials transportation, Penalties, Reporting and recordkeeping requirements.

          49 CFR Part 171

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

          49 CFR Part 172

          Education, Hazardous materials transportation, Hazardous waste, Incorporation by reference, Labeling, Markings, Packaging and containers, 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 178

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

          49 CFR Part 180

          Hazardous materials transportation, Motor carriers, Motor vehicle safety, Packaging and containers, Railroad safety, Reporting and recordkeeping requirements.

          In consideration of the foregoing, PHMSA is proposing to amend 49 CFR Chapter I as follows:

          PART 107--HAZARDOUS MATERIALS PROGRAM PROCEDURES

          0

   1. The authority citation for part 107 continues to read as follows:

      Authority: 49 U.S.C. 5101-5128, 44701; Pub. L. 101-410 section 4 (28 U.S.C. 2461 note); Pub. L. 104-121, sections 212-213; Pub. L. 104-134, section 31001; Pub. L. 112-141 section 33006; 49 CFR 1.81 and 1.97.

      0

   2. In Sec. 107.803, revise paragraph (c)(3) to read as follows:

      Sec. 107.803 Approval of an independent inspection agency (IIA).

      * * * * *

      (c) * * *

      (3) Detailed description of the applicant's qualifications and ability to perform the inspections and to verify the inspections required by part 178 and part 180 of this chapter; or those required under the terms of a special permit issued under this part.

      * * * * *

      0

   3. In Sec. 107.805, revise paragraphs (c)(3) and (c)(4), and add paragraph (c)(5) to read as follows:

      Page 49000

      Sec. 107.805 Approval of cylinder and pressure receptacle requalifiers.

      * * * * *

      (c) * * *

      (3) A certification that the facility will operate in compliance with the applicable requirements of subchapter C of this chapter;

      (4) The signature of the person making the certification and the date on which it was signed; and

      (5) For a mobile unit operation (as defined in Sec. 180.203 of subchapter C of this chapter), the type of equipment to be used, the specific vehicles to be used, the geographic area the applicant is requesting to operate within, and any differences between the mobile operation and the facility operation as described under paragraph (c)(2) of this section.

      * * * * *

      PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS

      0

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

      Authority: 49 U.S.C. 5101-5128, 44701; Pub. L. 101-410 section 4 (28 U.S.C. 2461 note); Pub. L. 104-121, sections 212-213; Pub. L. 104-134, section 31001; 49 CFR 1.81 and 1.97.

      0

   5. In Sec. 171.7, revise paragraphs (g)(1) and (n) to read as follows:

      Sec. 171.7 Reference material.

      * * * * *

      (g) * * *

      (1) 2015 ASME Boiler and Pressure Vessel Code (ASME Code), 2015 Edition, July 1, 2015 (as follows), into Sec. Sec. 172.102; 173.3; 173.5b; 173.24b; 173.302d; 173.306; 173.315; 173.318; 173.420; 178.255-

      1; 178.255-2; 178.255-14; 178.255-15; 178.273; 178.274; 178.276; 178.277; 178.320; 178.337-1; 178.337-2; 178.337-3; 178.337-4; 178.337-

      6; 178.337-16; 178.337-18; 178.338-1; 178.338-2; 178.338-3; 178.338-4; 178.338-5; 178.338-6; 178.338-13; 178.338-16; 178.338-18; 178.338-19; 178.345-1; 178.345-2; 178.345-3; 178.345-4; 178.345-7; 178.345-14; 178.345-15; 178.346-1; 178.347-1; 178.348-1; 179.400-3; 180.407.

      * * * * *

      (n) Compressed Gas Association (CGA), 1235 Jefferson Davis Highway, Arlington, VA 22202.

      (1) CGA C-1, Methods for Pressure Testing Compressed Gas Cylinders, 2016, into Sec. Sec. 178.36, 178.37, 178.38, 178.39, 178.42, 178.44, 178.45, 178.46, 178.47; 178.50; 178.51; 178.53; 178.55; 178.56; 178.57; 178.58; 178.59; 178.60; 178.61; 178.65; 178.68; 180.205, 180.209.

      (2) CGA C-3, Standards for Welding on Thin-Walled Steel Cylinders, 2005 (Reaffirmed 2011), into Sec. Sec. 178.47; 178.50; 178.51; 178.53; 178.55; 178.56; 178.57; 178.58; 178.59; 178.60; 178.61; 178.65; 178.68; 180.211.

      (3) CGA C-5, Cylinder Service Life--Seamless Steel High Pressure Cylinders, 1991 (Reaffirmed 1995), into Sec. 173.302a and 180.209.

      (4) CGA C-6, Standards for Visual Inspection of Steel Compressed Gas Cylinders, 2013, into Sec. Sec. 172.102, 173.3, 173.198, 173.302d, 180.205, 180.209, 180.211, 180.411, 180.519.

      (5) CGA C-6.1, Standards for Visual Inspection of High Pressure Aluminum Compressed Gas Cylinders, 2002, into Sec. Sec. 180.205; 180.209.

      (6) CGA C-6.2, Guidelines for Visual Inspection and Requalification of Fiber Reinforced High Pressure Cylinders, 1996, into Sec. 180.205.

      (7) CGA C-6.3, Guidelines for Visual Inspection and Requalification of Low Pressure Aluminum Compressed Gas Cylinders, 1991, into Sec. Sec. 180.205; 180.209.

      (8) CGA C-7, Guide to Preparation of Precautionary Labeling and Marking of Compressed Gas Containers, Appendix A, issued 2004, into Sec. 172.400a.

      (9) CGA C-8, Standard for Requalification of DOT-3HT Cylinder Design, 1985, into Sec. Sec. 180.205; 180.209.

      (10) CGA C-11, Recommended Practices for Inspection of Compressed Gas Cylinders at Time of Manufacture, 2001, into Sec. 178.35.

      (11) CGA C-12, Qualification Procedure for Acetylene Cylinder Design, 1994, into Sec. Sec. 173.301; 173.303; 178.59; 178.60.

      (12) CGA C-13, Guidelines for Periodic Visual Inspection and Requalification of Acetylene Cylinders, 2000, into Sec. Sec. 173.303; 180.205; 180.209.

      (13) CGA C-14, Procedures for Fire Testing of DOT Cylinder Pressure Relief Device Systems, 2005 (Reaffirmed 2010), into Sec. Sec. 173.301; 173.323.

      (14) CGA G-1.6, Standard for Mobile Acetylene Trailer Systems, 2011, in Sec. 173.301(g).

      (15) CGA G-2.2, Guideline Method for Determining Minimum of 0.2% Water in Anhydrous Ammonia, 1985, Reaffirmed 1997, into Sec. 173.315.

      (16) CGA G-4.1, Cleaning Equipment for Oxygen Service, 1985, into Sec. 178.338-15.

      (17) CGA P-20, Standard for the Classification of Toxic Gas Mixtures, 2003, Third Edition, into Sec. 173.115.

      (18) CGA S-1.1, Pressure Relief Device Standards--Part 1--Cylinders for Compressed Gases, (except paragraph 9.1.1), 2011, into Sec. Sec. 173.301; 173.304a; 178.75.

      (19) CGA S-1.2, Safety Relief Device Standards Part 2--Cargo and Portable Tanks for Compressed Gases, 1980, into Sec. Sec. 173.315; 173.318; 178.276; 178.277.

      (20) CGA S-7, Method for Selecting Pressure Relief Devices for Compressed Gas Mixtures in Cylinders, 2005, into Sec. 173.301.

      (21) CGA TB-2, Guidelines for Inspection and Repair of MC-330 and MC-331 Cargo Tanks, 1980, into Sec. Sec. 180.407; 180.413.

      (22) CGA TB-25, Design Considerations for Tube Trailers, 2008, into Sec. 173.301.

      * * * * *

      0

   6. In Sec. 171.23, revise paragraph (a)(4)(i) to read as follows:

      Sec. 171.23 Requirements for specific materials and packagings transported under the ICAO Technical Instructions, IMDG Code, Transport Canada TDG Regulations, or the IAEA Regulations.

      * * * * *

      (a) * * *

      (4) * * *

      (i) The cylinder has been requalified and marked in accordance with subpart C of part 180 of this subchapter, or has been requalified as authorized by the Associate Administrator;

      * * * * *

      PART 172--HAZARDOUS MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, TRAINING REQUIREMENTS, AND SECURITY PLANS

      0

   7. The authority citation for part 172 continues to read as follows:

      Authority: 49 U.S.C. 5101-5128, 44701; 49 CFR 1.81, 1.96 and 1.97.

      0

   8. In Sec. 172.400a, revise paragraph (a)(1) to read as follows:

      Sec. 172.400a Exceptions from labeling.

      * * * * *

      (a) * * *

      (1) A Dewar flask meeting the requirements in Sec. 173.320 of this subchapter, or a cylinder containing a Division 2.1, 2.2, or 2.3 material, that is durably and legibly marked in conformance with CGA C-

      7, appendix A (IBR; see Sec. 171.7 of this subchapter). However, if overpacked, marking (or appropriate labels) must be communicated on the exterior of the overpack unless visible from the outside in accordance with Sec. 173.25 of this subchapter.

      * * * * *

      Page 49001

      PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS

      0

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

      Authority: 49 U.S.C. 5101-5128, 44701; 49 CFR 1.81, 1.96 and 1.97.

      0

   10. In Sec. 173.3, revise paragraph (d)(1) to read as follows:

       Sec. 173.3 Packaging and exceptions.

       * * * * *

       (d) * * *

       (1) Except for Class 1, Class 7, or acetylene material, a cylinder containing a hazardous material may be overpacked in a salvage cylinder.

       * * * * *

       0

   11. In Sec. 173.301:

       0

       1. Revise paragraphs (a)(9) and (f)(4); and

          0

       2. In paragraphs (c) and (f), replace ``9.1.1.1'' with ``9.1.1'' in each place it appears.

          The revision reads as follows:

          Sec. 173.301 General requirements for shipment of compressed gases and other hazardous materials in cylinders, UN pressure receptacles and spherical pressure vessels.

          (a) * * *

          (9) Specification 2P, 2Q, 3E, 3HT, spherical 4BA, 4D, 4DA, 4DS, and 39 cylinders must be packed in strong non-bulk outer packagings. The outside of the combination package must be marked with an indication that the inner packagings conform to the prescribed specifications. Except for Specification 2P and 2Q containers, the ``OVERPACK'' marking in accordance with Sec. 173.25(a)(3) of this part may be used to satisfy the marking requirement of this paragraph. Display of the ``OVERPACK'' marking is not an indication that this combination package is an overpack.

          * * * * *

          (f) * * *

          (4) DOT 39 cylinders. (i) A pressure relief device is required on a DOT 39 cylinder regardless of cylinder size or filled pressure.

          (ii) A DOT 39 cylinder used for liquefied Division 2.1 materials must be equipped with a metal pressure relief device.

          (iii) Fusible pressure relief devices are not authorized on a DOT 39 cylinder containing a liquefied gas.

          (iv) Notwithstanding the requirements of paragraph (f)(1) of this section with respect to the minimum burst pressure of pressure relief devices, a pressure relief device on a DOT 39 cylinder used to transport compressed or liquefied oxidizing gases may have a minimum burst pressure within the range prescribed in Sec. Sec. 173.302(f)(2) or 173.304(f)(2), as appropriate.''

          * * * * *

          0

   12. In Sec. 173.302, revise paragraph (a)(2) to read as follows:

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

       (a) * * *

       (2) Adsorbed gas. A cylinder filled with an adsorbed gas must be offered for transportation in conformance with the requirements of paragraph (d) of this section and Sec. 173.301 of this subpart. In addition, UN pressure receptacles must meet the requirements in Sec. Sec. 173.301b, 173.302b, and 173.302c of this subpart, as applicable, and DOT-specification cylinders must meet the requirements of Sec. Sec. 173.301a, 173.302a and 173.302d, as applicable, of this subpart. Where more than one section applies to a cylinder, the most restrictive requirements must be followed.

       * * * * *

       0

   13. In Sec. 173.302a, revise paragraph (a)(3) to read as follows:

       Sec. 173.302a Additional requirements for shipment of nonliquefied (permanent) compressed gases in specification cylinders.

       (a) * * *

       (3) DOT 39 cylinders. When the cylinder is filled with a Division 2.1 flammable gas, the internal volume of the cylinder may not exceed 1.25 L (75 in\3\). For chemical under pressure (see Sec. 172.102, special provision 362 of this subchapter), the internal volume may not exceed 50 L (3050 in\3\).

       * * * * *

       0

   14. Add Sec. 173.302d to read as follows:

       Sec. 173.302d Additional requirements for the shipment of adsorbed gases in DOT-specification cylinders.

       (a) General. A cylinder filled with an adsorbed gas must be offered for transportation in DOT-specification cylinders subject to the requirements in this section, and Sec. Sec. 173.301 and 173.302 of this subpart.

       (b) Packaging. (1) DOT-3E1800, DOT-3AA2015, and DOT-3AA2265 cylinders must be used with a capacity between 0.4 and 7.3 liters.

       (2) Each cylinder authorized by this section must remain in dedicated product service for its entire life.

       (3) The maximum pressure inside each cylinder must be 0 psig at 70emsp14degF and 30 psig at 140emsp14degF.

       (4) The contents of the cylinders must be limited in pressure and volume so that if totally discharged into the overpack cylinder, the pressure in the overpack cylinder will not exceed \5/4\ of the MAWP at 55 degC (131emsp14degF).

       (5) The valve wheel of each cylinder must be secured by a strap that provides tension in the tightening direction. A plug must be placed in each valve and the cylinder and valve area must be shrink-

       wrapped before being placed in the overpack cylinder. A protective valve cap must be used on all pressure vessels except the DOT-3E1800 cylinder. Valves on the DOT-3E1800 cylinders must be protected in conformance with Sec. 173.40(d) of this part.

       (6) Prior to each shipment, the leak integrity of the overpack cylinder must be verified and have a leak rate no greater than 1 x 10-4 standard atmospheric cubic centimeters per second.

       (7) All closures of the overpack cylinder shall have a method to determine if they have been tampered with during transportation. The pressure indicating device on the overpack cylinder may be used to indicate tampering.

       (8) The shipper must instruct the carriers to reject or remove the overpack cylinder from transportation in the event that the pressure gauge drops below a pressure designated by the shipper.

       (9) Each overpack cylinder must be labeled for the hazardous material it contains.

       (10) Adsorbent material. Each cylinder is filled with a monolith solid microporous sorbent and/or bead-type sorbent onto which the gas is adsorbed. The gas remains adsorbed during transportation in essentially a solid state. The system is filled, operated, and transported at sub-atmospheric pressures and is described as a sub-

       atmospheric gas delivery system (SDS). The gas must be removed from the SDS using the input of external energy, such as a steady vacuum.

       (11) Overpack. (i) Cylinders authorized under this section must be transported in a non-DOT-specification full-opening, hinged-head or fully removable head, steel overpack cylinder. The overpack cylinder must be constructed to Section VIII, Division 1 of the ASME Code (IBR; see Sec. 171.7 of this subchapter) with a minimum design margin of 4 to 1. The minimum MAWP must be 75 psig. The maximum water capacity must be 450 L (119 gallons). The overpack cylinder must not be equipped with a pressure relief device. The cylinders must be securely positioned within the overpack to prevent excessive movement. The overpack cylinder must have gaskets, valves and fittings that are compatible

       Page 49002

       with the hazardous materials they contain. The overpack cylinder must have a pressure gauge clearly visible from the outside. The pressure gauge must be recessed into the overpack cylinder or otherwise protected from damage during transportation. The overpack cylinder must be pressurized to 3-5 psig with inert gas.

       (ii) Overpack testing. Each overpack cylinder must be visually inspected in conformance with CGA C-6 (IBR; see Sec. 171.7 of this subchapter) at least once every five years. In addition, each overpack must be pressure tested to a minimum test pressure of at least 1.5 times MAWP. The pressure must be maintained for at least 30 seconds. The cylinder must be examined under test pressure and removed from service if a leak or defect is found. The retest and inspection must be performed by a person trained and experienced in the use of the inspection and testing equipment.

       (iii) Overpack marking. Each overpack cylinder that is successfully requalified must be durably and legibly marked with the word ``Tested'' followed by the requalification date (month/year). The marking must be in letters and numbers at least 12 mm (0.5 inches) high. Stamping on the overpack sidewall is not permitted. The requalification marking may be placed on any portion of the upper end of the cylinder near the marking required by the following method, or on a metal plate permanently secured to the cylinder. The outside of each overpack cylinder must be plainly and durably marked on any portion of the upper end with ``OVERPACK CYLINDER'' (in lieu of the ``OVERPACK'' marking requirement of Sec. 173.25(a)(4) of this part), the proper shipping name of the hazardous material contained inside the overpack, the name and address of the consignee or consignor, and the name and address or registered symbol of the overpack manufacturer.

       (iv) Recordkeeping. The person who tested the overpack or that person's agent must retain a record of the most recent visual inspection and pressure test of the overpack until the cylinder is requalified. The records must be made available to a DOT representative upon request.

       (12) Sub-atmospheric gas delivery system (SDS) testing. Each cylinder, except DOT-3E cylinders, must be retested by persons trained to perform this procedure. DOT-3AA cylinders must be retested and marked in conformance with the requirements for DOT-3AA cylinders in 49 CFR part 180 or the requirements of a current DOT special permit for ultrasonic examination.

       (c) Gases. The gases permitted to be transported as adsorbed in DOT-specification cylinders in conformance with this section are:

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

       Proper shipping name/hazardous Hazard class/

       materials description division Identification No. Hazard zone

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

       Arsine.............................. 2.3 UN 2188..................... Zone A.

       Boron Trifluoride................... 2.3 UN 1008..................... Zone B.

       Hydrogen Selenide, Anhydrous........ 2.3 UN 2202..................... Zone A.

       Liquefied Gas, Toxic, Corrosive, 2.3 UN 3308.....................

       n.o.s. (Arsenic Pentafluoride).

       Liquefied Gas, Toxic, Corrosive, 2.3 UN 3308..................... Zone B.

       n.o.s. (Germanium Tetrafluoride).

       Liquefied Gas, Toxic, Corrosive, 2.3 UN 3308.....................

       n.o.s. (Phosphorus Trifluoride).

       Phosphine........................... 2.3 UN 2199..................... Zone A.

       Silicon Tetrafluoride............... 2.3 UN 1859..................... Zone B.

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

       0

   15. In Sec. 173.304a, add paragraph (a)(3) to read as follows:

       Sec. 173.304a Additional requirements for shipment of liquefied compressed gases in specification cylinders.

       (a) * * *

       (3) The internal volume of a DOT 39 cylinder may not exceed 1.23 liters (nominal 75 in\3\) for a liquefied flammable gas. This cylinder shall be equipped with a pressure relief device as defined by the commodity in CGA S-1.1 (IBR; see Sec. 171.7 of this subchapter). If the commodity is not listed in CGA S-1.1, a CG-7 pressure relief valve must be used.

       * * * * *

       0

   16. In Sec. 173.306, revise paragraph (g) to read as follows:

       Sec. 173.306 Limited quantities of compressed gases.

       * * * * *

       (g) Water pump system tank. A water pump system tank charged with compressed air or limited quantities of nitrogen or helium to not over 40 psig for single trip shipment to an installation site is excepted from labeling, and the specification packaging requirements of this subchapter when shipped under the following conditions. In addition, shipments of these tanks are not subject to subpart F (placarding) requirements of part 172 of this subchapter, and not subject to parts 174 (except Sec. 174.24) and 177 (except Sec. 177.817) of this subchapter.

       (1) The tank must be of steel or composite, with heads concave to pressure, having a rated water capacity not exceeding 120 gallons and with an outside diameter not exceeding 24 inches. Safety relief devices are not required.

       (2) The tank must be pneumatically tested to the manufacturer's specified maximum working pressure. The test pressure must be permanently marked on the tank.

       (3) The stress at prescribed pressure for steel tanks must not exceed 20,000 psi (or 25,000 psi for deep-draw steel), concave dome tanks using the formula:

       S = Pd/2t

       Where:

       S = wall stress in psi:

       P = prescribed pressure for the tank of at least three (3) times charged pressure at 70emsp14degF or 100 psig, whichever is greater;

       d = inside diameter in inches;

       t = minimum wall thickness, in inches.

       (4) For composite tanks, the minimum value of a hydrostatic leak test, per design, must be at least six (6) times the charge pressure at 70 degF or three (3) times the manufacturer's specified maximum working pressure, whichever is greater.

       (5) For steel and composite tanks, the burst pressure must be at least six (6) times the charge pressure at 70 degF or three (3) times the manufacturer's specified maximum working pressure, whichever is greater.

       (6) Each tank must be over-packed in a strong outer packaging in conformance with Sec. 173.301(h) of this part.

       (7) Transportation is limited to motor vehicle, railcar, and vessel. Transportation by aircraft is not authorized.

       * * * * *

       0

   17. In Sec. 173.309, revise the introductory text to read as follows:

       Page 49003

       Sec. 173.309 Fire extinguishers.

       This section applies to portable fire extinguishers for manual handling and operation, fire extinguishers for installation in aircraft, fire extinguishers for installation as part of a fire suppression system, and large fire extinguishers. Large fire extinguishers include fire extinguishers mounted on wheels for manual handling; fire extinguishing equipment or machinery mounted on wheels or wheeled platforms or units transported similar to (small) trailers; and fire extinguishers composed of a non-rollable pressure drum and equipment, and handled, for example, by forklift or crane when loaded or unloaded.

       * * * * *

       0

   18. In Sec. 173.312, revise paragraph (b)(1) to read as follows:

       Sec. 173.312 Requirements for shipment of MEGCs.

       * * * * *

       (b) * * *

       (1) An MEGC being filled with a liquefied compressed gas must have each cylinder filled separately by weight. Manifolding during filling is not authorized. The filling density for DOT-specification cylinders may not exceed the values contained in Sec. 173.304a(a)(2) of this subpart and for UN pressure receptacles may not exceed the values in accordance with Sec. 173.304b(b) of this subpart.

       * * * * *

       PART 178--SPECIFICATIONS FOR PACKAGINGS

       0

   19. The authority citation for part 178 continues to read as follows:

       Authority: 49 U.S.C. 5101-5128; 49 CFR 1.81 and 1.97.

       0

   20. In Sec. 178.35, add paragraph (f)(7) to read as follows:

       Sec. 178.35 General requirements for specification cylinders.

       * * * * *

       (f) * * *

       (7) Tare weight or mass weight, and water capacity marking. DOT-

       specification 4B, 4BA, 4BW, and 4E cylinders manufactured after January 1, 2017, must be marked with the tare weight or mass weight. Additionally, the cylinder must be permanently marked with the water capacity. The owner of the cylinder at the time of manufacture must ensure it is marked with the following information, as applicable:

       (i) Tare weight. The tare weight for a cylinder 25 pounds (11.34 kg) or less at the time of manufacture, with a lower tolerance of 3 percent and an upper tolerance of 1 percent; or for a cylinder exceeding 25 pounds (11.34 kg) at the time of manufacture, with a lower tolerance of 2 percent and an upper tolerance of 1 percent. The tare weight marking must be the actual weight of the fully assembled cylinder, including the valve(s) and other permanently affixed appurtenances. Removable protective cap(s) or cover(s) must not be included in the cylinder tare weight, or

       (ii) Mass weight. The mass weight for a cylinder 25 pounds (11.34 kg) or less at the time of manufacture, with a lower tolerance of 3 percent and an upper tolerance of 1 percent; or the mass weight marking for a cylinder exceeding 25 pounds (11.34 kg) at the time of manufacture, with a lower tolerance of 2 percent and an upper tolerance of 1 percent. The mass weight marking must be the actual weight of the fully assembled cylinder, excluding valve(s) and removable protective cap(s) or cover(s); and

       (iii) Water capacity. The water capacity for a cylinder 25 pounds (11.34 kg) water capacity or less, with a tolerance of minus 1 percent and no upper tolerance; or for a cylinder exceeding 25 pounds (11.34 kg) water capacity, with a tolerance of minus 0.5 percent and upper tolerance. The marked water capacity of the cylinder must be the capacity of the cylinder at the time of manufacture.

       * * * * *

       0

   21. In Sec. 178.36, revise paragraph (i) to read as follows:

       Sec. 178.36 Specification 3A and 3AX seamless steel cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of 5/3 times service pressure.

       (3) The minimum test pressure must be maintained for at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and previous to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error the test pressure cannot be maintained the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent, volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       * * * * *

       0

   22. In Sec. 178.37, revise paragraph (i) to read as follows:

       Sec. 178.37 Specification 3AA and 3AAX seamless steel cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of 5/3 times service pressure.

       (3) The minimum test pressure must be maintained for at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and previous to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error the test pressure cannot be maintained the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent, volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       * * * * *

       0

   23. In Sec. 178.38, revise paragraph (i) to read as follows:

       Sec. 178.38 Specification 3B seamless steel cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as defined in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA Pamphlet C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA Pamphlet C-1.

       (2) Cylinders must be tested as follows:

       (i) Each cylinder to at least two (2) times its service pressure; or

       (ii) One (1) cylinder out of each lot of 200 or fewer to at least three (3) times its service pressure.

       (3) When each cylinder is tested to the minimum test pressure, the minimum test pressure must be maintained at least 30 seconds and sufficiently longer to

       Page 49004

       ensure complete expansion. Any internal pressure applied after heat-

       treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       (5) When one (1) cylinder out of each lot of 200 or less is tested to at least 3 times service pressure, the balance of the lot must be pressure tested by the water-jacket, direct expansion or proof pressure test methods as defined in CGA C-1. The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. The cylinders must be subjected to at least 2 times service pressure and show no defect. Determination of expansion properties is not required.

       * * * * *

       0

   24. In Sec. 178.39, revise paragraph (i) to read as follows:

       Sec. 178.39 Specification 3BN seamless nickel cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGAC-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of at least two (2) times its service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       * * * * *

       0

   25. In Sec. 178.42, revise paragraph (f) to read as follows:

       Sec. 178.42 Specification 3E seamless steel cylinders.

       * * * * *

       (f) Pressure testing. Cylinders must withstand a pressure test as follows:

       (1) Lot Testing. One cylinder out of each lot of 500 or fewer must be subjected to a test pressure of 6,000 psig or higher. The testing equipment must be calibrated as prescribed in CGA Pamphlet C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA Pamphlet C-1

       (2) Pressure Testing. The remaining cylinders of the lot must be pressure tested by water jacket, direct expansion or proof pressure method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The cylinders must be examined under pressure of at least 3,000 psig and not to exceed 4,500 psig and show no defect. The test pressure must be maintained for at least 30 seconds and sufficiently longer to ensure complete examination.

       (3) Burst Testing. (i) The cylinder in paragraph (f)(1) of this section must burst at a pressure higher than 6,000 psig without fragmenting or otherwise showing lack of ductility, or must hold a pressure of 12,000 psig for 30 seconds without bursting. In which case, it must be subjected to a flattening test without cracking to six (6) times wall thickness between knife edges, wedge shaped 60-degree angle, rounded out to a half-inch radius. The inspector's report must be suitably changed to show results of latter alternate and flattening test.

       (ii) The cylinders in paragraph (f)(2) tested at a pressure in excess of 3,600 psig must burst at a pressure higher than 7,500 psig.

       * * * * *

       0

   26. In Sec. 178.44, revise paragraph (i) to read as follows:

       Sec. 178.44 Specification 3HT seamless steel cylinders for aircraft use.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to minimum of 5/3 times service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       * * * * *

       0

   27. In Sec. 178.45, revise paragraph (g) to read as follows:

       Sec. 178.45 Specification 3T seamless steel cylinder.

       * * * * *

       (g) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to minimum of 5/3 times service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       * * * * *

       0

   28. In Sec. 178.46, revise paragraph (g) to read as follows:

       Sec. 178.46 Specification 3AL seamless aluminum cylinders.

       * * * * *

       (g) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) The minimum test pressure must be the greater of the following:

       Page 49005

       (i) 450 psig regardless of service pressure;

       (ii) Two (2) times the service pressure for cylinders having service pressure less than 500 psig; or

       (iii) 5/3 times the service pressure for cylinders having a service pressure of 500 psig or greater.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower. If the test apparatus again fails to maintain the test pressure, the cylinder being tested must be condemned. Any internal pressure applied to the cylinder before any official test may not exceed 90 percent of the test pressure.

       (4) Permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       * * * * *

       0

   29. In Sec. 178.47, revise paragraph (j) to read as follows:

       Sec. 178.47 Specification 4DS welded stainless steel cylinders for aircraft use.

       * * * * *

       (j) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of at least two (2) times its service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (5) Cause for condemnation. Following the pressure test, the cylinder must be inspected. A cylinder with wall thickness less than that required by paragraph (f) of this section must be condemned. Bulges and cracks are cause for condemnation. Welded joint defects exceeding requirements of paragraph (k) of this section are cause for condemnation.

       * * * * *

       0

   30. Revise Sec. 178.50 to read as follows:

       Sec. 178.50 Specification 4B welded or brazed steel cylinders.

       (a) Type, size, pressure, and application. A DOT 4B is a welded or brazed steel cylinder with longitudinal seams that are forged lap-

       welded or brazed and with water capacity (nominal) not over 1,000 pounds and a service pressure of at least 150 but not over 500 psig. Cylinders closed in by spinning process are not authorized.

       (b) Steel. Open-hearth, electric or basic oxygen process steel of uniform quality must be used. Content percent may not exceed the following: carbon, 0.25; phosphorus, 0.045; sulphur, 0.050. The cylinder manufacturer must maintain a record of intentionally added alloying elements.

       (c) Identification of material. Pressure-retaining materials must be identified by any suitable method that does not compromise the integrity of the cylinder. Plates and billets for hotdrawn cylinders must be marked with the heat number.

       (d) Manufacture. Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart. No defect is permitted that is likely to weaken the finished cylinder appreciably. A reasonably smooth and uniform surface finish is required. Exposed bottom welds on cylinders over 18 inches long must be protected by footrings. Welding procedures and operators must be qualified in conformance with CGA C-3 (IBR, see Sec. 171.7 of this subchapter). Seams must be made as follows:

       (1) Brazing materials. Brazing materials must be by copper brazing, by copper alloy brazing, or by silver alloy brazing. Copper alloy composition must be: Copper, 95 percent minimum; Silicon, 1.5 percent to 3.85 percent; Manganese, 0.25 percent to 1.10 percent.

       (2) Brazed circumferential seams. Heads attached by brazing must have a driving fit with the shell, unless the shell is crimped, swedged, or curled over the skirt or flange of the head, and be thoroughly brazed until complete penetration by the brazing material of the brazed joint is secured. Depth of brazing of the joint must be at least four (4) times the minimum thickness of shell metal.

       (3) Welded circumferential seams. Circumferential seams are permitted by the welding process.

       (4) Longitudinal seams in shells. Longitudinal seams must be a forged lap joint design. When brazed, the plate edge must be lapped at least eight (8) times the thickness of the plate, laps being held in position, substantially metal to metal, by riveting or electric spot-

       welding; brazing must be done by using a suitable flux and by placing brazing material on one side of seam and applying heat until this material shows uniformly along the seam of the other side.

       (e) Welding or brazing. Only the attachment of neckrings, footrings, handles, bosses, pads, and valve protection rings to the tops and bottoms of cylinders by welding or brazing is authorized. Attachments and the portion of the cylinder to which they are attached must be made of weldable steel, the carbon content of which may not exceed 0.25 percent except in the case of 4130X steel, which may be used with proper welding procedure.

       (f) Wall thickness. The wall thickness of the cylinder must comply with the following requirements:

       (1) For cylinders with outside diameters over 6 inches, the minimum wall thickness must be 0.090 inch. In any case, the minimum wall thickness must be such that calculated wall stress at minimum test pressure (paragraph (i)(4) of this section) may not exceed the following values:

       (i) 24,000 psi for cylinders without longitudinal seam.

       (ii) 22,800 psig for cylinders having copper brazed or silver alloy brazed longitudinal seam.

       (iii) 18,000 psi for cylinders having forged lapped welded longitudinal seam.

       (2) Calculation must be made by the formula:

       S = P(1.3D\2\ + 0.4d\2\)/(D\2\ - d\2\)

       Where:

       S = wall stress in psi;

       P = minimum test pressure prescribed for water jacket test or 450 psig whichever is the greater;

       D = outside diameter in inches;

       d = inside diameter in inches.

       (g) Heat treatment. Cylinder heads, bodies or the completed cylinder, formed by drawing or pressing, must be uniformly and properly heat treated by an applicable method shown in table 1 of appendix A of this part before tests.

       (h) Opening in cylinders. Openings in cylinders must comply with the following:

       Page 49006

       (1) Any opening must be placed on other than a cylindrical surface.

       (2) Each opening in a spherical type of cylinder must be provided with a fitting, boss, or pad of weldable steel securely attached to the cylinder by fusion welding.

       (3) Each opening in a cylindrical type cylinder, except those for pressure relief devices, must be provided with a fitting, boss, or pad, securely attached to container by brazing or by welding.

       (4) If threads are used, they must comply with the following:

       (i) Threads must be clean cut, even without checks, and tapped to gauge.

       (ii) Taper threads must be of a length not less than as specified for American Standard taper pipe threads.

       (iii) Straight threads, must have at least four (4) engaged threads, must have tight fit and a calculated shear strength at least ten (10) times the test pressure of the cylinder; gaskets are required for straight threads and must be of sufficient quality to prevent leakage.

       (iv) A brass fitting may be brazed to the steel boss or flange on cylinders used as component parts of handheld fire extinguishers.

       (5) The closure of a fitting, boss, or pad must be adequate to prevent leakage.

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot testing. (i) At least one (1) cylinder randomly selected out of each lot of 200 or fewer must be tested by the water jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of 2 times service pressure.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (2) Pressure testing. (i) The remaining cylinders in the lot must be tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe as prescribed and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of at least two (2) times service pressure and show no defect.

       (j) Mechanical test. A mechanical test must be conducted to determine yield strength, tensile strength, elongation as a percentage, and reduction of area of material as a percentage as follows:

       (1) Testing is required on two (2) specimens removed from one (1) cylinder, or part thereof, heat-treated as required, as illustrated in appendix A to subpart C of this part. For lots of 30 or fewer, mechanical tests are authorized to be made on a ring at least 8 inches long removed from each cylinder and subjected to the same heat of material taken as the finished cylinder.

       (2) Specimens must comply with the following:

       (i) When a cylinder wall is \3/16\ inch thick or less, one the following gauge lengths is authorized: A gauge length of 8 inches with a width not over 1\1/2\ inches, a gauge length of 2 inches with a width not over 1\1/2\ inches, or a gauge length at least twenty-four (24) times the thickness with a width not over six (6) times the thickness.

       (ii) The specimen, exclusive of grip ends, may not be flattened. Grip ends may be flattened to within one inch of each end of the reduced section.

       (iii) When the size of a cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened or flattened cold, by pressure only, not by blows. When specimens are taken and prepared using this method, the inspector's report must show detailed information regarding such specimens in connection with the record of mechanical tests.

       (iv) Heating of a specimen for any purpose is not authorized.

       (3) The yield strength in tension must be the stress corresponding to a permanent strain of 0.2 percent of the gauge length. The following conditions apply:

       (i) The yield strength must be determined by either the ``offset'' method or the ``extension under load'' method as prescribed in ASTM E 8 (IBR, see Sec. 171.7 of this subchapter).

       (ii) In using the ``extension under load'' method, the total strain (or ``extension under load'') corresponding to the stress at which the 0.2 percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and adding thereto 0.2 percent of the gauge length. Elastic extension calculations must be based on an elastic modulus of 30,000,000. In the event of controversy, the entire stress-strain diagram must be plotted and the yield strength determined from the 0.2 percent offset.

       (iii) For the purpose of strain measurement, the initial strain reference must be set while the specimen is under a stress of 12,000 psi, and strain indicator reading must be set at the calculated corresponding strain.

       (iv) Cross-head speed of the testing machine may not exceed 18 inch per minute during yield strength determination.

       (v) The yield strength must not exceed 73 percent of the tensile strength.

       (k) Elongation. Mechanical test specimens must show at least a 20 percent elongation. However, elongation percentages may be reduced numerically by one (1) percentage for each 7,500 psi increase of tensile strength above 50,000 psi. The tensile strength may be incrementally increased by a maximum total of 30,000 psi.

       (l) Flattening test. (1) Cylinders. After pressure testing, a flattening test must be performed on one cylinder taken at random out of each lot of 200 or fewer by placing the cylinder between wedge-

       shaped knife edges having a 60 degree included angle, rounded to a half-inch radius. The longitudinal axis of the cylinder must be at a 90-deqree angle to knife edges during the test. For lots of 30 or fewer, flattening tests are authorized to be performed on a ring of at least 8 inches long removed from each cylinder and subjected to same heat of material taken as the finished cylinder.

       (2) Pipes. When cylinders are constructed of lap welded pipe, an additional flattening test is required, without evidence of cracking, up to six (6) times the wall thickness. In such case, the rings (crop ends) removed from each end of the pipe, must be tested with the weld 45emsp14degF or less from the point of greatest stress.

       (m) Acceptable results for flattening tests. There must be no evidence of cracking of the sample when it is flattened between flat plates to no more than six (6) times the wall thickness. If this test fails, one additional sample from the same lot may be taken. If this second sample fails, the entire lot must be condemned.

       (n) Condemned cylinders. (1) Unless otherwise stated in this section, if a

       Page 49007

       sample cylinder or specimen taken from a lot of cylinders fails the prescribed test, then two additional specimens must be selected from the same lot and subjected to the prescribed test. If either of these fails the test, then the entire lot must be condemned.

       (2) Reheat treatment of a condemned cylinder. Reheat treatment is authorized for a condemned cylinder in accordance with this paragraph. After reheat treatment, a cylinder must pass all prescribed tests in this section to be considered acceptable. Repair of brazed seams by brazing and welded seams by welding is authorized. For cylinders with an outside diameter of less than or equal to six (6) inches, welded seam repairs greater than one (1) inch in length shall require reheat treatment of the cylinder. For cylinders greater than an outside diameter of 6 inches, welded seam repairs greater than three (3) inches in length shall require reheat treatment.

       (o) Markings. (1) Markings must be as required as in Sec. 178.35 of this subpart and in addition must be stamped plainly and permanently in any of the following locations on the cylinder:

       (i) On shoulders and top heads whose wall thickness is not less than 0.087-inch thick;

       (ii) On side wall adjacent to top head for side walls which are not less than 0.090 inch thick;

       (iii) On a cylindrical portion of the shell that extends beyond the recessed bottom of the cylinder, constituting an integral and non-

       pressure part of the cylinder;

       (iv) On a metal plate attached to the top of the cylinder or permanent part thereof; sufficient space must be left on the plate to provide for stamping at least six retest dates; the plate must be at least \1/16\-inch thick and must be attached by welding, or by brazing. The brazing rod must melt at a temperature of 1100emsp14degF. Welding or brazing must be along all the edges of the plate;

       (v) On the neck, neckring, valve boss, valve protection sleeve, or similar part permanently attached to the top of the cylinder; or

       (vi) On the footring permanently attached to the cylinder, provided the water capacity of the cylinder does not exceed 30 pounds.

       (2) Embossing the cylinder head or sidewall is not permitted.

       0

   31. Revise Sec. 178.51 to read as follows:

       Sec. 178.51 Specification 4BA welded or brazed steel cylinders.

       (a) Type, size, pressure, and application. A DOT 4BA cylinder is a cylinder, either spherical or cylindrical design, with a water capacity of 1,000 pounds or less and a service pressure range of 225 to 500 psig. Closures made by the spinning process are not authorized.

       (1) Spherical type cylinder designs are permitted to have only one circumferentially welded seam.

       (2) Cylindrical type cylinder designs must be of circumferentially welded or brazed construction; longitudinally brazed or silver-soldered seams are also permitted.

       (b) Steel. The steel used in the construction of the cylinder must be as specified in table 1 of appendix A to this part. The cylinder manufacturer must maintain a record of intentionally added alloying elements.

       (c) Identification of material. Pressure-retaining material must be identified by any suitable method that does not compromise the integrity of the cylinder. Plates and billets for hotdrawn cylinders must be marked with the heat number.

       (d) Manufacture. Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart. No defect is permitted that is likely to appreciably weaken the finished cylinder. A reasonably smooth and uniform surface finish is required. Exposed bottom welds on cylinders over 18 inches long must be protected by footrings.

       (1) Seams must be made as follows:

       (i) Minimum thickness of heads and bottoms must be not less than 90 percent of the required thickness of the side wall.

       (ii) Circumferential seams must be made by welding or by brazing. Heads attached by brazing must have a driving fit with the shell unless the shell is crimped, swedged or curled over the skirt or flange of the head and must be thoroughly brazed until complete penetration by the brazing material of the brazed joint is secured. Depth of brazing from end of the shell must be at least four (4) times the thickness of shell metal.

       (iii) Longitudinal seams in shells must be made by copper brazing, copper alloy brazing, or by silver alloy brazing. Copper alloy composition must be: Copper 95 percent minimum, Silicon 1.5 percent to 3.85 percent, Manganese 0.25 percent to 1.10 percent. The melting point of the silver alloy brazing material must be in excess of 1,000emsp14degF. The plate edge must be lapped at least eight times the thickness of plate, laps being held in position, substantially metal to metal, by riveting or by electric spot-welding. Brazing must be done by using a suitable flux and by placing brazing material on one side of seam and applying heat until this material shows uniformly along the seam of the other side. Strength of longitudinal seam: Copper brazed longitudinal seam must have strength at least 3/2 times the strength of the steel wall.

       (2) Welding procedures and operators must be qualified in conformance with CGA C-3 (IBR, see Sec. 171.7 of this subchapter).

       (e) Welding or brazing. Welding or brazing of any attachment or opening to the heads of cylinders is permitted provided the carbon content of the steel does not exceed 0.25 percent except in the case of 4130 x steel, which may be used with proper welding procedure.

       (f) Wall thickness. The minimum wall thickness of the cylinder must meet the following conditions:

       (1) For any cylinder with an outside diameter of greater than 6 inches, the minimum wall thickness is 0.078 inch. In any case, the minimum wall thickness must be such that the calculated wall stress at the minimum test pressure may not exceed the lesser value of any of the following:

       (i) The value shown in table 1 of appendix A to this part, for the particular material under consideration;

       (ii) One-half of the minimum tensile strength of the material determined as required in paragraph (j) of this section;

       (iii) 35,000 psi; or

       (iv) Further provided that wall stress for cylinders having copper brazed longitudinal seams may not exceed 95 percent of any of the above values. Measured wall thickness may not include galvanizing or other protective coating.

       (2) Cylinders that are cylindrical in shape must have the wall stress calculated by the formula:

       S = P(1.3D\2\ + 0.4d\2\)/(D\2\ - d\2\)

       Where:

       S = wall stress in psi;

       P = minimum test pressure prescribed for water jacket test;

       D = outside diameter in inches;

       d = inside diameter in inches.

       (3) Cylinders that are spherical in shape must have the wall stress calculated by the formula:

       S = PD/4tE

       Where:

       S = wall stress in psi;

       P = minimum test pressure prescribed for water jacket test;

       D = outside diameter in inches;

       t = minimum wall thickness in inches;

       E = 0.85 (provides 85 percent weld efficiency factor which must be applied in the girth weld area and heat affected zones which zone must extend a distance of 6 times wall thickness from center line of weld);

       E = 1.0 (for all other areas).

       Page 49008

       (4) For a cylinder with a wall thickness less than 0.100 inch, the ratio of tangential length to outside diameter may not exceed 4.1.

       (g) Heat treatment. Cylinders must be heat treated in accordance with the following requirements:

       (1) Each cylinder must be uniformly and properly heat treated prior to test by the applicable method shown in table 1 of appendix A to this part. Heat treatment must be accomplished after all forming and welding operations, except that when brazed joints are used, heat treatment must follow any forming and welding operations, but may be done before, during or after the brazing operations see Sec. 178.51(m) for weld repairs.

       (2) Heat treatment is not required after the welding or brazing of weldable low carbon parts to attachments of similar material which have been previously welded or brazed to the top or bottom of cylinders and properly heat treated, provided such subsequent welding or brazing does not produce a temperature in excess of 400emsp14degF in any part of the top or bottom material.

       (h) Openings in cylinders. Openings in cylinders must comply with the following requirements:

       (1) Any opening must be placed on other than a cylindrical surface.

       (2) Each opening in a spherical type cylinder must be provided with a fitting, boss, or pad of weldable steel securely attached to the container by fusion welding.

       (3) Each opening in a cylindrical type cylinder must be provided with a fitting, boss, or pad, securely attached to container by brazing or by welding.

       (4) If threads are used, they must comply with the following:

       (i) Threads must be clean-cut, even, without checks and tapped to gauge.

       (ii) Taper threads must be of a length not less than that specified for American Standard taper pipe threads.

       (iii) Straight threads, having at least 4 engaged threads, must have a tight fit and a calculated shear strength of at least 10 times the test pressure of the cylinder. Gaskets, adequate to prevent leakage, are required.

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot testing. (i) At least one (1) cylinder randomly selected out of each lot of 200 or fewer must be tested by water jacket or direct expansion method as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (2) Pressure testing. (i) The remaining cylinders in the lot must be tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect.

       (j) Mechanical test. (1) A mechanical test must be conducted to determine yield strength, tensile strength, elongation as a percentage, and reduction of area of material as a percentage, as follows:

       (i) Cylinders. Testing is required on two (2) specimens removed from one cylinder or part thereof taken at random out of each lot of 200 or fewer. Samples must be removed as illustrated in appendix A to subpart C of this part.

       (ii) Spheres. Testing is required on two (2) specimens removed from the sphere or flat representative sample plates of the same heat of material taken at random from the steel used to produce the spheres. Samples (including plates) must be taken from each lot of 200 or fewer. The flat steel from which two specimens are to be removed must receive the same heat of material taken as the as the spheres themselves. Samples must be removed as illustrated in appendix A to subpart C of this part.

       (2) Specimens must comply with the following:

       (i) When a cylinder wall is \3/16\ inch thick or less, one the following gauge lengths is authorized: A gauge length of 8 inches with a width not over 1\1/2\ inches, a gauge length of 2 inches with a width not over 1\1/2\ inches, or a gauge length at least twenty-four (24) times the thickness with a width not over six (6) times the thickness.

       (ii) The specimen, exclusive of grip ends, may not be flattened. Grip ends may be flattened to within one inch of each end of the reduced section.

       (iii) When size of the cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened or flattened cold, by pressure only, not by blows. When specimens are so taken and prepared, the inspector's report must show in connection with record of physical tests detailed information in regard to such specimens.

       (iv) Heating of a specimen for any purpose is not authorized.

       (3) The yield strength in tension must be the stress corresponding to a permanent strain of 0.2 percent of the gauge length. The following conditions apply:

       (i) The yield strength must be determined by either the ``offset'' method or the ``extension under load'' method as prescribed in ASTM E 8 (IBR, see Sec. 171.7 of this subchapter).

       (ii) In using the ``extension under load'' method, the total strain (or ``extension under load''), corresponding to the stress at which the 0.2 percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and adding thereto 0.2 percent of the gauge length. Elastic extension calculations must be based on an elastic modulus of 30,000,000. In the event of controversy, the entire stress-strain diagram must be plotted and the yield strength determined from the 0.2 percent offset.

       (iii) For the purpose of strain measurement, the initial strain reference must be set while the specimen is under a stress of 12,000 psi, and the strain indicator reading must be set at the calculated corresponding strain.

       (k) Elongation. Mechanical test specimens must show at least a 40 percent elongation for a 2-inch gauge length or at least 20 percent in other cases. However, elongation percentages may be reduced numerically by 2 percent for 2-inch specimens, and by 1 percent in other cases, for each 7,500 psi increase of tensile strength above 50,000 psi. The tensile strength may be incrementally increased by a maximum total of 30,000 psi.

       (l) Tests of welds. Except for brazed seams, welds must be tested as follows:

       (1) Tensile test. A specimen must be removed from one cylinder of each lot

       Page 49009

       of 200 or fewer, or welded test plate. The welded test plate must be of one of the heats in the lot of 200 or fewer which it represents, in the same condition and approximately the same thickness as the cylinder wall except that in no case must it be of a lesser thickness than that required for a quarter size Charpy impact specimen. The weld must be made by the same procedures and subjected to the same heat of material taken as the major weld on the cylinder. The specimen must be taken from across the major seam and must be prepared and tested in conformance with and must meet the requirements of CGA C-3 (IBR, see Sec. 171.7 of this subchapter). Should this specimen fail to meet the requirements, one additional specimen must be taken from two additional cylinders or welded test plates from the same lot and tested. If any of these latter two specimens fail to meet the requirements, the entire lot represented must be condemned.

       (2) Guided bend test. A root bend test specimen must be removed from the cylinder or welded test plate, used for the tensile test specified in paragraph (l)(1) of this section. The specimen must be taken from across the circumferential seam and must be prepared and tested in conformance with and must meet the requirements of CGA C-3. Should this specimen fail to meet the requirements, one additional specimen must be taken from two additional cylinders or welded test plates from the same lot and tested. If any of these latter two specimens fail to meet the requirements, the entire lot represented must be condemned.

       (3) Alternate guided-bend test. This test may be used and must be as required by CGA C-3. The specimen must be bent until the elongation at the outer surface, adjacent to the root of the weld, between the lightly scribed gage lines a to b, must be at least 20 percent, except that this percentage may be reduced for steels having a tensile strength in excess of 50,000 psig, as provided in paragraph (k) of this section. Should the specimen fail to meet the requirements, one additional specimen must be taken from two additional cylinders or welded test plates from the same lot and tested. If any of these latter two specimens fail to meet the requirements, the entire lot represented must be condemned.

       (m) Condemned cylinders.

       (1) Unless otherwise stated in this section, if a sample cylinder or specimen taken from a lot of cylinders fails the prescribed test, then two additional specimens must be selected from the same lot and subjected to the prescribed test. If either of these additional specimens fails the test, then the entire lot must be condemned.

       (2) Reheat treatment of a condemned cylinder. Reheat treatment is authorized for a condemned cylinder in accordance with this paragraph. After reheat, a cylinder must pass all prescribed tests in this section to be acceptable. Repair of brazed seams by brazing and welded seams by welding is considered authorized. For cylinders with an outside diameter of less than or equal to six (6) inches, welded seam repairs greater than one (1) inch in length shall require reheat treatment of the cylinder. For cylinders greater than an outside diameter of six (6) inches, welded seam repairs greater than three (3) inches in length shall require reheat treatment.

       (n) Markings. (1) Markings must be as required in Sec. 178.35 of this subpart and in addition must be stamped plainly and permanently in one of the following locations on the cylinder:

       (i) On shoulders and top heads whose wall thickness is not less than 0.087 inch thick;

       (ii) On side wall adjacent to top head for side walls not less than 0.090 inch thick;

       (iii) On a cylindrical portion of the shell that extends beyond the recessed bottom of the cylinder constituting an integral and non-

       pressure part of the cylinder;

       (iv) On a plate attached to the top of the cylinder or permanent part thereof; sufficient space must be left on the plate to provide for stamping at least six retest dates; the plate must be at least \1/16\-

       inch thick and must be attached by welding, or by brazing at a temperature of at least 1100 degF, throughout all edges of the plate;

       (v) On the neck, neckring, valve boss, valve protection sleeve, or similar part permanently attached to the top of the cylinder; or

       (vi) On the footring permanently attached to the cylinder, provided the water capacity of the cylinder does not exceed 30 pounds.

       (2) Embossing the cylinder head or side is not permitted.

       0

   32. In Sec. 178.53, revise paragraph (h) to read as follows:

       Sec. 178.53 Specification 4D welded steel cylinders for aircraft use.

       * * * * *

       (h) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot Testing. (i) At least one cylinder selected at random out of each lot of 200 or fewer must be tested by water-jacket or direct expansion as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of three (3) times service pressure.

       (iii) The minimum test pressure must be maintained be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect.

       * * * * *

       0

   33. In Sec. 178.55, revise paragraph (i) to read as follows:

       Sec. 178.55 Specification 4B240ET welded or brazed cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot Testing. (i) At least one (1) cylinder selected at random out of each lot of 200 or fewer must be tested by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure

       Page 49010

       applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect.

       (3) Burst testing. (i) For purposes of burst testing, each 1,000 cylinders or fewer successively produced each day constitutes a lot. All cylinders of a lot must be of identical size, construction heat treatment, finish, and quality.

       (ii) One cylinder must be selected from each lot and be hydrostatically pressure tested to destruction. If this cylinder bursts below five (5) times the service pressure, then two additional cylinders from the same lot as the previously tested cylinder must be selected and subjected to this test. If either of these cylinders fails by bursting below five (5) times the service pressure then the entire lot must be condemned.

       * * * * *

       0

   34. In Sec. 178.56, revise paragraph (i) to read as follows:

       Sec. 178.56 Specification 4AA480 welded steel cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot testing. (i) At least one (1) cylinder selected at random out of each lot of 200 or fewer must be tested by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (v) If a selected cylinder fails, then two (2) additional specimens must be selected at random from the same lot and subjected to the prescribed testing. If either of these fails the test, then each cylinder in that lot must be tested as prescribed in paragraph (i)(l) of this section.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect. A cylinder showing a defect must be condemned unless it may be requalified under paragraph (m) of this section.

       * * * * *

       0

   35. In Sec. 178.57, revise paragraph (i) to read as follows:

       Sec. 178.57 Specification 4L welded insulated cylinders.

       * * * * *

       (i) Pressure testing. Each cylinder, before insulating and jacketing, must successfully withstand a pressure test as follows:

       (1) The cylinder must be tested by water-jacket, direct expansion, or proof pressure test methods as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) There must be no evidence of leakage, visible distortion or other defect.

       * * * * *

       0

   36. In Sec. 178.58, revise paragraph (i) to read as follows:

       Sec. 178.58 Specification 4DA welded steel cylinders for aircraft use.

       * * * * *

       (i) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) The test must be by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (3) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (4) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       * * * * *

       0

   37. In Sec. 178.59, revise paragraph (h) to read as follows:

       Sec. 178.59 Specification 8 steel cylinders with porous fillings for acetylene.

       * * * * *

       (h) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot testing. (i) At least one (1) cylinder selected at random out of each lot of 200 or fewer must be tested by water-jacket or direct expansion method

       Page 49011

       as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of 750 psig.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (v) If the tested cylinder fails, each cylinder remaining in the lot may be tested in lieu of paragraph (h)(2) of this section by the water-jacket or direct expansion method as prescribed in CGA C-1. Those passing are acceptable.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be pressure tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested between 500 and 600 psig and show no defect.

       * * * * *

       0

   38. In Sec. 178.60, revise paragraph (j) to read as follows:

       Sec. 178.60 Specification 8AL steel cylinders with porous fillings for acetylene.

       * * * * *

       (j) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot Testing. (i) At least one (1) cylinder selected at random out of each lot of 200 or less must be tested by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR; see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of 750 psig.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (v) If the tested cylinder fails, each remaining cylinder in the lot may be tested in lieu of paragraph (j)(2) of this section by the water-jacket or direct expansion method as prescribed in CGA C-1. Those passing are acceptable.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be pressure tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested between 500 and 600 psig and show no defect.

       * * * * *

       0

   39. Revise Sec. 178.61 to read as follows:

       Sec. 178.61 Specification 4BW welded steel cylinders with electric-

       arc welded seam.

       (a) Type, size, pressure, and application. A DOT 4BW cylinder has a spherical or cylindrical design, a water capacity of 1,000 pounds or less, and a service pressure range of 225 to 500 psig. Closures made by the spinning process are not authorized.

       (1) Spherical designs are permitted to have only one circumferentially electric-arc welded seam.

       (2) Cylindrical designs must be of circumferentially welded electric-arc construction; longitudinally electric-arc welded seams are permitted.

       (b) Steel. (1) The steel used in the construction of the cylinder must be as specified in table 1 of appendix A to this part. The cylinder manufacturer must maintain a record of intentionally added alloying elements.

       (2) Material for heads must meet the requirements of paragraph (b)(1) of this section or be open hearth, electric or basic oxygen carbon steel of uniform quality. Content percent may not exceed the following: Carbon 0.25, Manganese 0.60, Phosphorus 0.045, Sulfur 0.050. Heads must be hemispherical or ellipsoidal in shape with a maximum ratio of 2:1. If low carbon steel is used, the thickness of such heads must be determined by using a maximum wall stress of 24,000 psi in the formula described in paragraph (g)(4) of this section.

       (c) Identification of material. Pressure-retaining materials must be identified by any suitable method that does not compromise the integrity of the cylinder. Plates and billets for hotdrawn cylinders must be marked with the heat number.

       (d) Manufacture. Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart and the following:

       (1) No defect is permitted that is likely to weaken the finished cylinder appreciably. A reasonably smooth and uniform surface is required. Exposed bottom welds on cylinders over 18 inches long must be protected by footrings. Minimum thickness of heads may not be less than 90 percent of the required thickness of the sidewall. Heads must be concave to pressure.

       (2) Circumferential seams must be by electric-arc welding. Joints must be butt with one member offset (joggle butt) or with a lap joint. Lap joints must have a minimum overlap of at least four (4) times nominal sheet thickness.

       (3) Longitudinal electric-arc welded seams (in shells) must be of the butt welded type. Welds must be made by a machine process including automatic feed and welding guidance mechanisms. Longitudinal seams must have complete joint penetration, and must be free from undercuts, overlaps or abrupt ridges or valleys. Misalignment of mating butt edges may not exceed \1/6\ inch of nominal sheet thickness or \1/32\ inch whichever is less. All joints with nominal sheet thickness up to and including \1/8\ inch must be tightly butted. When nominal sheet thickness is greater than \1/8\ inch, the joint must be gapped with maximum distance equal to one-half the nominal sheet thickness or \1/

       32\ inch whichever is less. Joint design, preparation, and fit-up must be such that requirements of this paragraph (d) are satisfied.

       (4) Welding procedures and operators must be qualified in accordance with CGA C-3 (IBR, see Sec. 171.7 of this subchapter).

       (e) Welding of attachments. The attachment to the tops and bottoms only of cylinders by welding of neckrings,

       Page 49012

       footrings, handles, bosses, pads and valve protection rings is authorized provided that such attachments and the portion of the container to which they are attached are made of weldable steel, the carbon content of which may not exceed 0.25 percent.

       (f) Non-destructive examination. (1) Welds of the cylinders must be subjected to radioscopic or radiographic examination as follows:

       (2) Radioscopy or radiography must be in conformance with CGA C-3 (IBR; see Sec. 171.7 of this subchapter). Maximum joint efficiency will be 1.0 when each seam is examined completely. Maximum joint efficiency will be 0.90 when one cylinder from each lot of 50 consecutively welded cylinders is spot examined. In addition, one out of the first five cylinders welded following a shutdown of welding operations exceeding four hours must be spot examined. Spot radiographs, when required, must be made of a finished welded cylinder and must include the girth weld for 2 inches in both directions from the intersection of the longitudinal and girth welds and include at least 6 inches of the longitudinal weld. Maximum joint efficiency of 0.75 will be permissible without radiography. When fluoroscopic examination is used, permanent film records need not be retained.

       (g) Wall thickness. (1) For outside diameters over 6 inches the minimum wall thickness must be 0.078 inch. In any case, the minimum wall thickness must be such that the wall stress calculated by the formula listed in paragraph (g)(2) of this section may not exceed the lesser value of any of the following:

       (i) The value referenced in paragraph (b) of this section for the particular material under consideration.

       (ii) One-half of the minimum tensile strength of the material determined as required in paragraph (k) of this section.

       (iii) 35,000 psi.

       (2) Stress must be calculated by the following formula:

       S = 2P(1.3D\2\ + 0.4d\2\)/E(D\2\ - d\2\)

       Where:

       S = wall stress, psi;

       P = service pressure, psig;

       D = outside diameter, inches;

       d = inside diameter, inches;

       E = joint efficiency of the longitudinal seam (from paragraph (d) of this section).

       (3) For a cylinder with a wall thickness less than 0.100 inch, the ratio of tangential length to outside diameter may not exceed 4 to 1 (4:1).

       (h) Heat treatment. Cylinders must be heat treated in accordance with the following requirements:

       (1) Each cylinder must be uniformly and properly heat treated prior to test by the applicable method referenced in table 1 of appendix A to this part. Heat treatment must be accomplished after all forming and welding operations, except that when brazed joints are used, heat treatment must follow any forming and welding operations, but may be done before, during or after the brazing operations (see Sec. 178.51(m) of this subpart for weld repairs).

       (2) Heat treatment is not required after welding of weldable low-

       carbon parts to attachments of similar material which have been previously welded to the top or bottom of cylinders and properly heat treated, provided such subsequent welding does not produce a temperature in excess of 400emsp14degF in any part of the top or bottom material.

       (i) Openings in cylinders. Openings in cylinders must comply with the following requirements:

       (1) All openings must be in heads or bases.

       (2) Each opening in a spherical-type cylinder must be provided with a fitting, boss, or pad of weldable steel securely attached to the cylinder by fusion welding.

       (3) Each opening in a cylindrical-type cylinder must be provided with a fitting, boss, or pad securely attached to the cylinder by welding.

       (4) If threads are used, they must comply with the following:

       (i) Threads must be clean cut, even, without checks, and tapped to gauge.

       (ii) Taper threads must be of length not less than as specified for American Standard Taper Pipe Threads.

       (iii) Straight threads, having at least four (4) engaged threads, must have a tight fit and calculated shear strength at least ten (10) times the test pressure of the cylinder. Gaskets, adequate to prevent leakage, are required.

       (iv) A brass fitting may be brazed to the steel boss or flange on cylinders used as component parts of handheld fire extinguishers.

       (j) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

       (1) Lot testing. (i) At least one cylinder randomly selected out of each lot of 200 or less must be tested by the water-jacket or direct expansion method as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (iv) Permanent volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure.

       (2) Pressure testing. (i) The remaining cylinders in each lot must be pressure tested by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

       (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect.

       (3) Burst testing. (i) One finished cylinder selected at random out of each lot of 500 or less must be hydrostatically tested to four (4) times service pressure without bursting.

       (k) Mechanical tests. Mechanical tests must be conducted to determine yield strength, tensile strength, elongation as a percentage, and reduction of area of material as a percentage, as follows:

       (1) Specimens must be taken from one cylinder after heat treatment as illustrated in appendix A to subpart C of this part, chosen at random from each lot of 200 or fewer, as follows:

       (i) Body specimen. One specimen must be taken longitudinally from the body section at least 90 degrees away from the weld.

       (ii) Head specimen. One specimen must be taken from either head on a cylinder when both heads are made of the same material. However, if the two heads are made of differing materials, a specimen must be taken from each head.

       (iii) If due to welded attachments on the top head there is insufficient surface from which to take a specimen, it may be taken from a representative head of the same heat treatment as the test cylinder.

       (2) Specimens must conform to the following:

       (i) When a cylinder wall is \3/16\ inch thick or less, one the following gauge lengths is authorized: A gauge length of 8 inches with a width not over 1\1/2\

       Page 49013

       inches, a gauge length of 2 inches with a width not over 1\1/2\ inches, or a gauge length at least twenty-four (24) times the thickness with a width not over six (6) times the thickness.

       (ii) The specimen, exclusive of grip ends, may not be flattened. Grip ends may be flattened to within 1 inch of each end of the reduced section.

       (iii) When size of the cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened or flattened cold, by pressure only, not by blows. When specimens are taken and prepared in this manner, the inspector's report must show in connection with the record of physical tests detailed information in regard to such specimens.

       (iv) Heating of a specimen for any purpose is not authorized.

       (3) The yield strength in tension must be the stress corresponding to a permanent strain of 0.2 percent of the gauge length. The following conditions apply:

       (i) The yield strength must be determined by either the ``off-set'' method or the ``extension under load'' method as prescribed in ASTM E 8 (IBR, see Sec. 171.7 of this subchapter).

       (ii) In using the ``extension under load'' method, the total strain (or ``extension under load''), corresponding to the stress at which the 0.2-percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and adding thereto 0.2 percent of the gauge length. Elastic extension calculations must be based on an elastic modulus of 30,000,000. In the event of controversy, the entire stress-strain diagram must be plotted and the yield strength determined from the 0.2-

       percent offset.

       (iii) For the purpose of strain measurement, the initial strain reference must be set while the specimen is under a stress of 12,000 psi, and the strain indicator reading must be set at the calculated corresponding strain.

       (iv) Cross-head speed of the testing machine may not exceed \1/8\ inch per minute during yield strength determination.

       (l) Elongation. Mechanical test specimens must show at least a 20 percent elongation. However, elongation percentages may be reduced numerically by one (1) for each 7,500 psi of tensile strength above 50,000 psi to a maximum of four (4) increments (i.e., 30,000 psi).

       (m) Tests of welds. Welds must be subjected to the following tests:

       (1) Tensile test. A specimen must be removed from one cylinder of each lot of 200 or fewer. The specimen must be taken from across the longitudinal seam and must be prepared and tested in conformance with the requirements of CGA C-3 (IBR, see Sec. 171.7 of this subchapter).

       (2) Guided bend test. A root bend test specimen must be removed from the cylinder or welded test plate used for the tensile test specified in paragraph (m)(1) of this section. Specimens must be taken from across the longitudinal seam and must be prepared and tested in conformance with the requirements of CGA C-3. If the specimen fails to meet the requirements, one specimen each must be taken from two additional cylinders or welded test plates from the same lot as the previously tested cylinder or added test plate and tested. If either of these latter two specimens fails to meet the requirements, the entire lot represented must be condemned.

       (3) Alternate guided bend test. This test may be used and must be as required by CGA C-3. The specimen must be bent until the elongation at the outer surface, adjacent to the root of the weld, between the lightly scribed gauge lines a to b, must be at least 20 percent, except that this percentage may be reduced for steels having a tensile strength in excess of 50,000 psi, as provided in paragraph (l) of this section. Should this specimen fail to meet the requirements, one additional specimen such must be taken from two additional cylinders or welded test plates from the same lot and tested as the previously tested cylinder or added test plate. If either of these latter two specimens fails to meet the requirements, the entire lot represented must be condemned.

       (n) Rejected cylinders. (1) Unless otherwise stated, if a sample cylinder or specimen taken from a lot of cylinders fails the prescribed test, then two additional specimens must be selected from the same lot and subjected to the prescribed test. If either of these fails the test, then the entire lot must be rejected.

       (2) Reheat treatment of condemned cylinders. Reheat treatment is authorized for a condemned cylinder in accordance with this paragraph. After reheat treatment, a cylinder must pass all prescribed tests in this section to be considered acceptable. Repair of welded seams by welding is authorized. For cylinders less than or equal to an outside diameter of 6 inches, welded seam repairs greater than 1 inch in length shall require reheat treatment of the cylinder. For cylinders greater than an outside diameter of 6 inches, welded seam repairs greater than 3 inches in length shall require reheat treatment.

       (o) Markings. (1) Markings must be as required in Sec. 178.35 of this subpart and in addition must be stamped plainly and permanently in one of the following locations on the cylinder:

       (i) On shoulders and top heads whose wall thickness is not less than 0.087 inch thick.

       (ii) On side wall adjacent to top head for side walls not less than 0.090 inch thick.

       (iii) On a cylindrical portion of the shell that extends beyond the recessed bottom of the cylinder constituting an integral and non-

       pressure part of the cylinder.

       (iv) On a plate attached to the top of the cylinder or permanent part thereof; sufficient space must be left on the plate to provide for stamping at least six retest dates; the plate must at least \1\/

       16-inch thick and must be attached by welding at a temperature of 1,100emsp14degF, throughout all edges of the plate.

       (v) On the neck, neckring, valve boss, valve protection sleeve, or similar part permanently attached to the top of the cylinder.

       (vi) On the footring permanently attached to the cylinder, provided the water capacity of the cylinder does not exceed 30 pounds.

       (2) Embossing the cylinder head or side wall is not permitted.

       (p) Inspector's report. In addition to the information required by Sec. 178.35 of this subpart, the inspector's report must indicate the type and amount of radiography.

       0

   40. In Sec. 178.65, revise paragraph (f) to read as follows:

       Sec. 178.65 Specification 39 non-reusable (non-refillable) cylinders.

       * * * * *

       (f) Pressure testing. (1) Each cylinder must be proof pressure tested as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

       (2) The leakage test must be conducted by submersion under water or by some other method that will be equally sensitive.

       (3) If the cylinder leaks, evidences visible distortion or evidences any other defect while under test, it must be condemned (see paragraph (h) of this section).

       * * * * *

       0

   41. In Sec. 178.68:

       0

       1. Revise paragraphs (b), (e), (h), (j) introductory text, (j)(1), (k), (l) and (m);

          0

       2. Redesignate paragraph (n) as paragraph (o); and

          Page 49014

          0

       3. Add new paragraph (n).

          The revisions, redesignation, and addition read as follows:

          Sec. 178.68 Specification 4E welded aluminum cylinders.

          * * * * *

          (b) Authorized material. The cylinder must be constructed of aluminum of uniform quality. The following chemical analyses are authorized:

          Table 1--Authorized Materials

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

          Chemical analysis-- limits in

          Designation percent 5154

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

          Iron plus silicon...................... 0.45 maximum.

          Copper................................. 0.10 maximum.

          Manganese.............................. 0.10 maximum.

          Magnesium.............................. 3.10/3.90.

          Chromium............................... 0.15/0.35.

          Zinc................................... 0.20 maximum.

          Titanium............................... 0.20 maximum.

          Others, each........................... 0.05 maximum.

          Others, total.......................... 0.15 maximum.

          Aluminum............................... remainder.

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

          Note to Table 1: The aluminum used in the construction of the cylinder must be as specified in Table 1. The cylinder manufacturer must maintain a record of intentionally added alloying elements.

          * * * * *

          (e) Welding. The attachment to the tops and bottoms only of cylinders by welding of neckrings, flanges, footrings, handles, bosses, pads, and valve protection rings is authorized. However, such attachments and the portion of the cylinder to which it is attached must be made of weldable aluminum alloys.

          * * * * *

          (h) Pressure testing. Each cylinder must successfully withstand a pressure test as follows:

          (1) All cylinders with a wall stress greater than 18,000 psi must be tested by water-jacket or direct expansion method as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

          (i) Each cylinder must be tested to a minimum of two (2) times service pressure.

          (ii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

          (iii) Permanent volumetric expansion may not exceed 12 percent of the total volumetric expansion at test pressure.

          (2) Lot testing. (i) Cylinders with a wall stress of 18,000 psi or less may be lot tested. At least one cylinder randomly selected out of each lot of 200 or less must be tested by the water-jacket or direct expansion method as prescribed in CGA C-1. The testing equipment must be calibrated as prescribed in CGA C-1. All testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1.

          (ii) Each cylinder must be tested to a minimum of two (2) times service pressure.

          (iii) The minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

          (iv) Permanent volumetric expansion may not exceed 12 percent of the total volumetric expansion at test pressure.

          (3) Pressure testing. (i) For cylinders with a wall stress of 18,000 psi or less, the remaining cylinders of the lot must be pressure tested by the water-jacket, direct expansion or proof pressure test methods as defined in CGA C-1. The minimum test pressure must be maintained for a specific timeframe, and the testing equipment must be calibrated as prescribed in CGA C-1. Further, all testing equipment and pressure indicating devices must be accurate within the parameters defined in CGA C-1. Determination of expansion properties is not required.

          (ii) Each cylinder must be tested to a minimum of two (2) times service pressure and show no defect.

          (4) Burst Testing. One (1) finished cylinder selected at random out of each lot of 1000 or less must be hydrostatically tested to four (4) times service pressure without bursting. Inability to meet this requirement must result in condemnation of the lot.

          * * * * *

          (j) Mechanical test. A mechanical test must be conducted to determine yield strength, tensile strength, elongation as a percentage, and reduction of area of material as a percentage as follows:

          (1) The test is required on two (2) specimens removed from one cylinder or part thereof as illustrated in appendix A to subpart C of this part taken at random out of each lot of 200 or fewer.

          * * * * *

          (k) Acceptable results for mechanical tests. An acceptable result of the mechanical test requires a minimum tensile strength as defined in paragraph (f)(1)(ii) of this section, an elongation to at least 7 percent and yield strength not over 80 percent of tensile strength.

          (l) Weld tests. Welds of the cylinder are required to successfully pass the following tests:

          (1) Reduced section tensile test. A specimen must be removed from the cylinder used for the mechanical tests specified in paragraph (j) of this section. The specimen must be taken from across the seam; edges must be parallel for a distance of approximately 2 inches on either side of the weld. The specimen must be fractured in tension. The actual breaking stress must be a minimum of at least 30,000 psi. The apparent breaking stress calculated on the minimum design wall thickness must be a minimum of two (2) times the stress calculated under paragraph (f)(2) of this section. If the specimen fails to meet the requirements, the lot must be condemned except that specimens may be taken from two (2) additional cylinders from the same lot as the previously tested specimens. If either of the latter specimens fails to meet requirements, the entire lot represented must be condemned.

          (2) Guided bend test. A bend test specimen must be removed from the cylinder used for the mechanical test specified in paragraph (j) of this section. The specimen must be taken across the circumferential seam, must be a minimum of 1\1/2\ inches wide, edges must be parallel and rounded with a file, and back-up strip, if used, must be removed by machining. The specimen must be tested as follows:

          (i) The specimen must be bent to refusal in the guided bend test jig as illustrated in CGA C-3 (IBR, see Sec. 171.7 of this subchapter). The root of the weld (inside surface of the cylinder) must be located away from the ram of the jig. The specimen must not show a crack or other open defect exceeding \1/8\ inch in any direction upon completion of the test. Should this specimen fail to meet the requirements, one additional specimen must be taken from two additional cylinders from the same lot and tested. If either of the latter specimens fails to meet requirements, the entire lot represented must be condemned.

          (ii) Alternate guided bend test. This test may be used as an alternate to the

          Page 49015

          guided bend test. The test specimen must be in conformance with The Aluminum Association's ``Welding Aluminum: Theory and Practice, Fourth Edition, 2002'' (IBR, see Sec. 171.7 of this subchapter). If the specimen fails to meet the requirements, one additional specimen must be taken from two additional cylinders or welded test plates from the same lot and tested. If any of these latter two specimens fails to meet the requirements, the entire lot must be condemned.

          (m) Condemned cylinders. (1) Unless otherwise stated, if a sample cylinder or specimen taken from a lot of cylinders fails the prescribed test, then two additional specimens must be selected from the same lot and subjected to the prescribed test. If either of these fails the test, then the entire lot must be condemned.

          (2) Repair of welded seams is authorized. Acceptable cylinders must pass all prescribed tests.

          (n) Markings. (1) Markings must be as required in Sec. 178.35 of this subpart and in addition must be stamped plainly and permanently in one of the following locations on the cylinder:

          (i) On the neck, neckring, valve boss, valve protection sleeve, or similar part permanently attached to the top of the cylinder.

          (ii) On the footring permanently attached to the cylinder, provided the water capacity of the cylinder does not exceed 30 pounds.

          (2) Embossing the cylinder head or side wall is not permitted.

          * * * * *

          0

   42. In Sec. 178.70, revise paragraph (d) to read as follows:

       Sec. 178.70 Approval of UN pressure receptacles.

       * * * * *

       (d) Modification of approved pressure receptacle design type. Modification of an approved UN/ISO pressure receptacle design type is not authorized without the approval of the Associate Administrator. However, modification of an approved UN/ISO pressure receptacle design type is authorized without an additional approval of the Associate Administrator provided the design modification is covered under the UN/

       ISO standard for the design type. A manufacturer seeking modification of an approved UN/ISO pressure receptacle design type may be required to submit design qualification test data to the Associate Administrator before production.

       * * * * *

       PART 180--CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS

       0

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

       Authority: 49 U.S.C. 5101-5128; 49 CFR 1.81 and 1.97.

       0

   44. In Sec. 180.203:

       0

       1. Add definitions for the words ``accuracy,'' ``accuracy grade,'' ``actual test pressure,'' ``calibrated cylinder,'' ``error,'' ``master gauge,'' ``mobile unit,'' ``over-pressurized,'' ``percent permanent expansion,'' ``precision,'' ``proof pressure test,'' ``reference gauge,'' and ``service pressure'' in alphabetical order; and

          0

       2. Revise the definition for the words ``commercially free of corrosive components,'' ``defect,'' and ``test pressure.''

          The additions and revisions read as follows:

          Sec. 180.203 Definitions

          * * * * *

          Accuracy means the conformance of a particular reading to a known standard. Accuracy is expressed as the percentage of error from, or degree of closeness to, the true value, such as the difference between the measurement result displayed by the instrument and the value obtained when a measurement standard is used to perform the measurement. This value may be represented as a percent of full scale.

          Accuracy grade means the inherent quality of the device. It expresses the maximum error allowed for the device at any reading. Accuracy grade is expressed as a percentage of the full scale of the device.

          Actual test pressure means the pressure applied to a cylinder during a requalification test.

          Calibrated cylinder means a cylinder that has certified calibration points of pressure with corresponding expansion values. It is a secondary, derived standard used for the verification and demonstration of test system accuracy and integrity.

          Commercially free of corrosive components means a hazardous material having a moisture content less than 55 ppm and free of components that will adversely react with the cylinder (e.g. chemical stress corrosion).

          * * * * *

          Defect means an imperfection requiring a cylinder to be rejected or condemned.

          * * * * *

          Error means the difference between the measured values and the true value.

          * * * * *

          Master gauge means a pressure indicating device that is used as a calibration standard, has an inherent accuracy grade equal to or better than the requirement for the pressure indicating device in the test apparatus, and is an instrument not used in the daily performance of cylinder testing.

          Mobile unit means a vehicle specifically authorized under a RIN to carry out requalification operations identified under the RIN within a geographic area no more than 100 miles from the principle place of business of the RIN holder. Mobile units must comply with the requirements outlined in the approval issuance letter from the Associate Administrator for Hazardous Materials Safety (see Sec. 107.805 of subchapter A of this chapter).

          * * * * *

          Over-pressurized means a condition in which the internal pressure applied to a cylinder has reached or exceeded the yield point of the cylinder.

          Percent permanent expansion means the ratio of permanent expansion to total expansion, expressed as a percentage. The calculation for percent permanent expansion is the permanent expansion divided by total expansion times 100.

          * * * * *

          Precision of a measurement means the degree of scatter of the recorded values when the measurement is repeated a number of times under the same conditions.

          Proof pressure test means a pressure test by interior pressurization without the determination of a cylinder's expansion. A gas (e.g., air) or a liquid (e.g., water) is used as a means to achieve interior pressurization.

          * * * * *

          Reference gauge means a pressure indicating device that is used in the daily verification of a proof test system, and has an inherent accuracy equal to or better than the requirement for the device to be checked.

          * * * * *

          Service pressure means the rated service pressure marked on the cylinder.

          Test pressure means the minimum prescribed pressure required for the requalification of a cylinder.

          * * * * *

          0

   45. In Sec. 180.205:

       0

       1. Revise paragraphs (c) introductory text, (d), (g)(3), (h)(3), (i)(1)(viii), (i)(2), and (i)(3); and

          0

       2. Add paragraphs (f)(5), (f)(6), (i)(1)(ix), (i)(1)(x), (i)(1)(xi) and (j).

          The additions and revisions read as follows:

          Page 49016

          Sec. 180.205 General requirements for requalification of specification cylinders.

          * * * * *

          (c) Periodic requalification of cylinders. Each cylinder bearing a DOT-specification marking must be requalified and marked as specified in the Requalification Table in this subpart. Each cylinder bearing a DOT special permit (or exemption) number must be requalified and marked in conformance with this section and the terms of the applicable special permit (or exemption). No cylinder may be filled with a hazardous material and offered for transportation in commerce unless that cylinder has been successfully requalified and marked in conformance with this subpart. A cylinder may be requalified at any time during or before the month and year that the requalification is due. However, a cylinder filled before the requalification becomes due may remain in service until it is emptied. A cylinder with a specified service life may not be refilled and offered for transportation after its authorized service life has expired.

          * * * * *

          (d) Conditions requiring test and inspection of cylinders. Without regard to any other periodic requalification requirements, a cylinder must be tested and inspected in accordance with this section prior to further use if--

          (1) The cylinder shows evidence of dents, corrosion, cracked or abraded areas, leakage, or any other condition that might render it unsafe for use in transportation;

          (2) The cylinder has been in an accident and has been damaged to an extent that may adversely affect its lading retention capability;

          (3) The cylinder shows evidence of or is known to have thermal damage, or have been over-heated;

          (4) Except as provided in Sec. 180.212 of this subpart, the cylinder shows evidence of grinding; or

          (5) The Associate Administrator determines that the cylinder may be in an unsafe condition.

          * * * * *

          (f) * * *

          (5) Shot blasting of cylinders is permitted. Grinding, sanding, or any other removal of wall thickness of a cylinder is not permitted, except by an authorized facility, as provided in Sec. 180.212 of this subpart for the removal of surface corrosion.

          (6) Chasing of cylinder threads to clean them is permitted, but removal of metal must not occur. Re-tapping of cylinder threads is not permitted, except by the original manufacturer, as provided in Sec. 180.212 of this subpart.

          (g) * * *

          (3) Each day before retesting, the retester shall confirm, by using a calibrated cylinder or other method authorized in writing by the Associate Administrator, that:

          (i) The pressure-indicating device (PID), as part of the retest equipment, is accurate within 1.0% of the prescribed test pressure of any cylinder tested that day. The PID must meet Industrial Class 1 (1.0% deviation from the end value) with a scale appropriate to the test pressure of the cylinder. The accuracy of the PID within the test system can be demonstrated at any point within 500 psig of the actual test pressure for test pressures at or above 3,000 psig, or 10% of the actual test pressure for test pressures below 3,000 psig.

          (ii) The expansion-indicating device (EID), as part of the retest equipment, gives a stable reading of expansion and is accurate to 1.0% of the total expansion of any cylinder tested or 0.1 cc, whichever is larger. The EID must be accurate (1.0% deviation from the end value) of its full scale. The weigh scales must be capable of providing total expansion measurements to an accuracy of 1.0% or 0.05 ounce (1.5 g), whichever is greater.

          * * * * *

          (h) * * *

          (3) Unless the cylinder is repaired or rebuilt in conformance with requirements in Sec. 180.211of this subpart, it may not be filled with a hazardous material and offered for transportation where use of a specification packaging is required.

          * * * * *

          (i) * * *

          (1) * * *

          (viii) For an aluminum or an aluminum-lined composite special permit cylinder, the cylinder is known to have been or shows evidence of having been overheated. Arc burns must be considered evidence of overheating.

          (ix) The cylinder is known to have been or shows evidence of having been over-pressurized.

          (x) For a cylinder with a specified service life, its authorized service life has expired.

          (xi) The cylinder has been stamped on the sidewall, except as provided in part 178 of this subchapter.

          (2) When a cylinder must be condemned, the requalifier must--

          (i) Communicate condemnation of the cylinder as follows: (A) Stamp a series of X's over the DOT-specification number and the marked pressure or stamp ``CONDEMNED'' on the shoulder, top head, or neck using a steel stamp;

          (B) For composite cylinders, securely affix to the cylinder a label with the word ``CONDEMNED'' overcoated with epoxy near, but not obscuring, the original cylinder manufacturer's label; or

          (C) As an alternative to the stamping or labeling as described in this paragraph (i)(2), at the direction of the owner, the requalifier may render the cylinder incapable of holding pressure; and

          (ii) Notify the cylinder owner, in writing, that the cylinder is condemned and may not be filled with hazardous material and offered for transportation in commerce where use of a specification packaging is required.

          (3) No person may remove, obliterate, or alter the required condemnation communication of paragraph (i)(2) of this section.

          (j) Training materials. Training materials (such as CGA C-1.1; see Sec. 171.7, Table I of this subchapter) may be used for training persons who requalify cylinders using the volumetric expansion test method.

          0

   46. In Sec. 180.207, revise paragraphs (a)(3), (b)(2), (c) introductory text, (d) introductory text, (d)(1), and (d)(3) to read as follows:

       Sec. 180.207 Requirements for requalification of UN pressure receptacles.

       (a) * * *

       (3) A pressure receptacle with a specified service life may not be requalified after its authorized service life has expired, but must be condemned in accordance with Sec. 180.205(i)(x) of this subpart.

       (b) * * *

       (2) Each pressure receptacle that fails requalification must be condemned in conformance with Sec. 180.205(i) of this subpart or the applicable ISO requalification standard.

       * * * * *

       (c) Requalification interval. Each UN pressure receptacle that becomes due for periodic requalification must be requalified at the interval specified in the following table before it is filled: * * *

       * * * * *

       (d) Requalification procedures. Each UN pressure receptacle must be requalified in conformance with the procedures contained in the following standards, as applicable. Furthermore, when a pressure test is performed on a UN pressure receptacle, the test must be a water jacket volumetric expansion test suitable for the determination of the cylinder expansion or a hydraulic proof pressure test. The test equipment must conform to the accuracy requirements in Sec. 180.205(g) of this subpart. Alternative methods (e.g., acoustic emission) or requalification procedures may be

       Page 49017

       performed if prior approval has been obtained in writing from the Associate Administrator.

       (1) Seamless steel: Each seamless steel UN pressure receptacle, including MEGC's pressure receptacles exceeding 150 L capacity, must be requalified in conformance with ISO 6406 (IBR, see Sec. 171.7 of this subchapter). However, UN cylinders with a tensile strength greater than or equal to 950 MPa must be requalified by ultrasonic examination in conformance with ISO 6406.

       * * * * *

       (3) Dissolved acetylene UN cylinders: Each dissolved acetylene cylinder must be requalified in conformance with ISO 10462 (IBR, see Sec. 171.7 of this subchapter). The porous mass and the shell must be requalified no sooner than five (5) years and no later than ten (10) years from the date of manufacture. Thereafter, subsequent requalifications of the shell must be performed at least once every ten (10) years.

       * * * * *

       0

   47. In Sec. 180.209, revise paragraphs (a), (b), (c), (e), (g), (l)(1) and (m) to read as follows:

       Sec. 180.209 Requirements for requalification of specification cylinders.

       (a) Periodic qualification of cylinders. Each specification cylinder that becomes due for periodic requalification, as specified in the following table, must be requalified and marked in conformance with the requirements of this subpart before it is filled. Requalification records must be maintained in conformance with Sec. 180.215 of this subpart. Table 1 follows:

       Table 1--Requalification of Cylinders

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

       Specification under which Minimum test Requalification

       cylinder was made pressure (psig) \1\ period (years)

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

       DOT 3....................... 3000 psig........... 5.

       DOT 3A, 3AA................. 5/3 times service 5, or 12 (see Sec.

       pressure, except 180.209(b), (f),

       noncorrosive (h), and (j)).

       service (see Sec.

       180.209(g)).

       DOT 3AL\2\.................. 5/3 times service 5, or 12 (see Sec.

       pressure. Sec. 180.209(j)

       and (m)).

       DOT 3AX, 3AAX............... 5/3 times service 5

       pressure.

       3B, 3BN..................... 2 times service 5 or 10 (see Sec.

       pressure (see Sec. 180.209(f)).

       180.209(g)).

       3E.......................... Test not required...

       3HT......................... 5/3 times service 3 (see Sec. Sec.

       pressure. 180.209(k) and

       180.213(c)).

       3T.......................... 5/3 times service 5.

       pressure.

       4AA480...................... 2 times service 5 or 10 (see Sec.

       pressure (see Sec. 180.209(h)).

       180.209(g)).

       4B, 4BA, 4BW, 4B-240ET...... 2 times service 5, 10, or 12 (see

       pressure, except Sec. 180.209(e),

       non-corrosive (f), and (j)).

       service (see Sec.

       180.209(g)).

       4D, 4DA, 4DS................ 2 times service..... 5.

       DOT 4E...................... 2 times service 5 or 10 ((see Sec.

       pressure, except Sec. 180.209(e)).

       non-corrosive (see

       Sec. 180.209(g)).

       4L.......................... Test not required...

       8, 8AL...................... .................... 10 or 20 (see Sec.

       180.209(i)).

       Exemption or special permit See current See current

       cylinder. exemption or exemption or

       special permit. special permit.

       Foreign cylinder (see Sec. As marked on 5 (see Sec. Sec.

       173.301(j) of this cylinder, but not 180.209(l) and

       subchapter for restrictions less than 5/3 of 180.213(d)(2)).

       on use). any service or

       working pressure

       marking.

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

       \1\ For cylinders not marked with a service pressure, see Sec.

       173.301a(b) of this subchapter.

       \2\ For special permit (or exemption) aluminum cylinders marked DOT 3AL,

       see Sec. 173.23(c) of this subchapter.

       (b) DOT 3A or 3AA cylinders. (1) A cylinder conforming to specification DOT 3A or 3AA with a water capacity of 56.7 kg (125 pounds) or less may be marked with a star and requalified every 10 years instead of every 5 years, provided the cylinder conforms to all of the following conditions:

       (i) The cylinder is used exclusively for air; argon; cyclopropane; ethylene; helium; hydrogen; krypton; neon; nitrogen; nitrous oxide; oxygen; sulfur hexafluoride; xenon; chlorinated hydrocarbons, fluorinated hydrocarbons, liquefied hydrocarbons, and mixtures thereof that are commercially free from corroding components; permitted mixtures of these gases (see Sec. 173.301(d) of this subchapter); and permitted mixtures of these gases with up to 30 percent by volume of carbon dioxide, provided the gas has a moisture content less than 55 ppm.

       (ii) The cylinder is not used in any cascade, bank, group, rack or vehicle. The cylinder is not used in self-contained underwater breathing apparatus (SCUBA), self-contained breathing apparatus (SCBA), or in an emergency respirator.

       (iii) The permanent expansion does not exceed 5 percent of the total expansion.

       (iv) The results of the hydrostatic test meet one of the following requirements:

       (A) The elastic expansion does not exceed the manufacturer's marked rejection elastic expansion (REE) limit on the cylinder;

       (B) The elastic expansion does not exceed the applicable rejection limit tabulated in CGA C-5 (IBR, see Sec. 171.7 of this subchapter); or

       (C) Either the average wall stress or the maximum wall stress does not exceed the corresponding wall stress limitation determined by computing the REE limit in conformance with CGA C-5.

       (v) The cylinder is dried immediately after hydrostatic testing to remove all traces of water.

       (vi) The cylinder is stamped with a five-pointed star at least one-

       fourth of an inch high immediately following the test date to indicate compliance with this paragraph (b)(1).

       (2) If a cylinder has not been used exclusively for the gases specifically identified in paragraph (b)(1)(i) of this section, but currently conforms with all other provisions of paragraph (b)(1) of this section, it may be requalified every 10 years instead of every 5 years, only after the cylinder has been retested, marked, and placed into exclusive use and gas service in compliance with paragraph (b)(1) of this section.

       (3) If, at any time, a cylinder marked with a five-pointed star is used in a manner other than as specified in paragraph (b)(1) of this section, the star following the most recent test date must be obliterated. The cylinder must be requalified within five years from the

       Page 49018

       marked test date, or if the required five-year requalification period has passed, the cylinder must be requalified prior to the first filling with a compressed gas.

       (c) DOT 4-series cylinders. A DOT 4-series cylinder, except a 4L cylinder, that at any time shows evidence of a leak, internal or external corrosion, denting, bulging or rough usage to the extent that it is likely to be weakened appreciably, or that has lost 5 percent or more of its official tare weight must be requalified before being refilled and offered for transportation. Refer to CGA C-6 or C-6.3 (IBR, see Sec. 171.7 of this subchapter), as applicable, regarding cylinder weakening. After testing, the actual tare weight must be recorded as the new tare weight on the test report and marked on the cylinder. The previous tare weight must be strike-lined through, but not obliterated.

       * * * * *

       (e) Proof pressure test. A cylinder made in conformance with DOT Specifications 4B, 4BA, 4BW, or 4E protected externally by a suitable corrosion-resistant coating and used exclusively for non-corrosive gas that is commercially free from corroding components may be requalified by volumetric expansion testing or proof pressure testing every 10 years instead of every 5 years. However, a cylinder used for reclaiming, recycling, or recovering refrigerant gases must be requalified by volumetric expansion testing every 5 years. Reclaimed, recycled, or recovered refrigerant gases are considered to be corrosive due to contamination. When subjected to a proof pressure test, as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter) and consistent with the applicable specification testing requirement in Part 178 of this subchapter, the cylinder must be carefully examined under test pressure and removed from service if a leak or defect is found.

       * * * * *

       (g) Visual inspections. A cylinder conforming to a specification listed in the table in this paragraph and used exclusively in the service indicated may, instead of a periodic hydrostatic test, be given a complete external visual inspection at the time periodic requalification becomes due. External visual inspection must be in conformance with CGA C-6 or C-6.3, as applicable (IBR, see Sec. 171.7 of this subchapter). When this inspection is used instead of hydrostatic testing, subsequent inspections are required at five-year intervals after the first inspection. Inspections must be made only by persons holding a current RIN and the results recorded and maintained in conformance with Sec. 180.215 of this subpart. Records must include: date of inspection (month and year); DOT-specification number; cylinder identification (registered symbol and serial number, date of manufacture, and owner); type of cylinder protective coating (including statement as to need of refinishing or recoating); conditions checked (e.g., leakage, corrosion, gouges, dents or digs in shell or heads, broken or damaged footring or protective ring or fire damage); and disposition of cylinder (returned to service, returned to cylinder manufacturer for repairs or condemned). A cylinder passing requalification by the external visual inspection must be marked in conformance with Sec. 180.213 of this subpart. Specification cylinders must be in exclusive service as shown in the following table:

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

       Cylinders conforming to-- Used exclusively for--

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

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 4AA480 Anhydrous ammonia of at least

       99.95% purity.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 3B, Butadiene, inhibited, that is

       DOT 4B, DOT 4BA, DOT 4BW. commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 3B, Cyclopropane that is

       DOT 4AA480, DOT 4B, DOT 4BA, DOT 4BW. commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 4B, Chlorinated hydrocarbons and

       DOT 4BA, DOT 4BW, DOT 4E. mixtures thereof that are

       commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 4B, Fluorinated hydrocarbons and

       DOT 4BA, DOT 4BW, DOT 4E. mixtures thereof that are

       commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 3B, Liquefied hydrocarbon gas that

       DOT 4B, DOT 4BA, DOT 4BW, DOT 4E. is commercially free of

       corroding components.

       DOT 3A, DOT 3AA, DOT 3A480X, DOT 3B, Liquefied petroleum gas that

       DOT 4B, DOT 4BA, DOT 4BW, DOT 4E. meets the detail requirements

       limits in Table 1 of ASTM

       1835, Standard Specification

       for Liquefied Petroleum (LP)

       Gases or an equivalent

       standard containing the same

       limits.

       DOT 3A, DOT 3AA, DOT 3B, DOT 4B, DOT Methylacetylene-propadiene,

       4BA, DOT 4BW, DOT 4E. stabilized, that is

       commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3B, DOT 4B, DOT Methylacetylene-propadiene,

       4BA, DOT 4BW, DOT 4E. stabilized, that is

       commercially free from

       corroding components.

       DOT 3A, DOT 3AA, DOT 3B, DOT 4B, DOT Propylene that is commercially

       4BA, DOT 4BW, DOT 4E. free from corroding

       components.

       DOT 3A, DOT 3AA, DOT 3B, DOT 4B, DOT Anhydrous mono,

       4BA, DOT 4BW. ditrimethylamines that are

       commercially free from

       corroding components.

       DOT 4B240, DOT 4BW240.................. Ethyleneimine, stabilized.

       DOT 4BW................................ Alkali metal alloys, liquid,

       n.o.s., Alkali metal

       dispersions or Alkaline earth

       metal dispersions, Potassium,

       Potassium Sodium alloys and

       Sodium that are commercially

       free of corroding components.

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

       * * * * *

       (j) Cylinder used as a fire extinguisher. Only a DOT-specification cylinder used as a fire extinguisher in conformance with Sec. 173.309(a) of this subchapter may be requalified in conformance with this paragraph (j).

       (1) A DOT 4B, 4BA, 4B240ET or 4BW cylinder used as a fire extinguisher may be tested as follows:

       (i) For a cylinder with a water capacity of 5.44 kg (12 pounds) or less, by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). A requalification must be performed by the end of 12 years after the original test date and at 12-year intervals thereafter.

       (ii) The testing procedures, calibration of the testing equipment, accuracy of the pressure indicating device, accuracy of the testing equipment must be as prescribed in CGA C-1.

       Page 49019

       (iii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iv) When testing using the water-jacket or direct expansion test method, the minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (v) The permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure.

       (vi) When testing using the proof pressure test method, the minimum test pressure must be maintained for a specific time frame as prescribed in CGA C-1. Any internal pressure applied prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (vii) When subjected to a proof pressure test, the cylinder must be carefully examined under test pressure and removed from service if a leak or defect is found.

       (2) For a cylinder having a water capacity over 5.44 kg (12 pounds), by the water-jacket, direct expansion or proof pressure test methods as prescribed in CGA C-1. For the water-jacket or direct expansion test, the requalification must be performed by the end of 12 years after the original test date and at 12-year intervals theafter. For the proof-pressure test, a requalification must be performed by the end of 12 years after the original test date and at seven (7) year intervals.

       (ii) The testing procedures, calibration of the testing equipment, accuracy of the pressure indicating device, and accuracy of the testing equipment must be as prescribed in CGA C-1.

       (iii) Each cylinder must be tested to a minimum of two (2) times service pressure.

       (iv) When testing using the water-jacket or direct expansion test method, the minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (v) The permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure. For DOT 4E cylinders, the permanent volumetric expansion may not exceed 12 percent of total volumetric expansion at test pressure.

       (vi) When testing using the proof pressure test method, the minimum test pressure must be maintained for a specific timeframe as prescribed in CGA C-1 (IBR, see Sec. 171.7 of this subchapter). Any internal pressure applied prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (vii) When subjected to a proof pressure test, the cylinder must be carefully examined under test pressure and removed from service if a leak or defect is found.

       (3) A DOT 3A, 3AA, or 3AL cylinder must be requalified by:

       (i) The water-jacket or direct expansion method. A requalification must be performed 12 years after the original test date and at 12-year intervals thereafter.

       (ii) The testing procedures, calibration of the testing equipment, accuracy of the pressure indicating device, accuracy of the testing equipment must be as prescribed in CGA C-1.

       (iii) Each cylinder must be tested to a minimum of \5/3\ times service pressure.

       (iv) When testing using the water-jacket or direct expansion test method, the minimum test pressure must be maintained at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied prior to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus or operator error, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 psig, whichever is lower.

       (v) The permanent volumetric expansion may not exceed 10 percent of total volumetric expansion at test pressure. For DOT 4E cylinders, the permanent volumetric expansion may not exceed 12 percent of total volumetric expansion at test pressure.

       * * * * *

       (l) * * *

       (1) It has been inspected, tested and marked in conformance with the procedures and requirements of this subpart or the Associate Administrator has authorized the filling company to fill foreign cylinders under an alternative method of qualification; and

       * * * * *

       (m) DOT-3AL cylinders manufactured of 6351-T6 aluminum alloy. In addition to the periodic requalification and marking described in Sec. 180.205 of this subpart, each cylinder manufactured of aluminum alloy 6351-T6 with a marked service pressure equal to or exceeding 1,800 psi must be requalified and inspected for sustained load cracking in conformance with the non-destructive examination method described in the following table. A cylinder with cracks must be condemned in conformance with Sec. 180.205(i) of this subpart.

       Requalification and Inspection of DOT-3AL Cylinders Made of Aluminum Alloy 6351-T6

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

       Sustained Load Cracking Requalification

       Requalification requirement Examination procedure \1\ Condemnation Criteria \2\ period (years)

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

       Eddy current examination combined with Eddy current--In Any crack in the neck of 5

       visual inspection. conformance with 2 thread lengths or more.

       appendix C of this part.

       Visual inspection--In

       conformance with CGA C-

       6.1 (IBR; see Sec.

       171.7 of this

       subchapter).

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

       \1\ The requalifier performing eddy current must be familiar with the eddy current equipment and must

       standardize (calibrate) the system in accordance with the requirements provided in appendix C to this part.

       \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.

       Page 49020

       (1) Examination procedure. Each facility performing eddy current examination with visual inspection must develop, update, and maintain a written examination procedure applicable to the test equipment it uses to perform eddy current examinations.

       (2) Visual examinations. Visual examinations of the neck and shoulder area of the cylinder must be conducted in conformance with CGA C-6.1 (IBR, see Sec. 171.7 of this subchapter).

       (3) Condemnation criteria. A cylinder must be condemned if the eddy current examination combined with visual examination reveals any crack in the neck of two thread lengths or more, or if visual inspection reveals any crack in the neck or shoulder area.

       0

   48. In Sec. 180.211, revise paragraphs (c) and (e)(1) to read as follows:

       Sec. 180.211 Repair, rebuilding and reheat treatment of DOT-4 series specification cylinders.

       * * * * *

       (c) Additional requirements for the repair or recondition of a DOT-

       4L cylinder. (1) Repairs to a DOT-4L welded insulated cylinder must be performed in conformance with paragraphs (a) and (b) of this section with the exception that other welding procedures permitted by CGA C-3 (IBR, see Sec. 171.7 of this subchapter), and not excluded by the definition of ``rebuild,'' are authorized. DOT 4L cylinders must meet additional requirements for repair specified in Sec. 180.211(c), including being pressure-tested in conformance with the specifications under which the cylinder was originally manufactured. DOT 4L cylinders that undergo procedures not defined as a repair in Sec. 180.203 are not subject to the requirements of Sec. 180.211(c), including the requirement to be pressure-tested in conformance with the specifications under which the cylinder was originally manufactured.

       (2) After repair, the cylinder must be--

       (i) Pressure tested in accordance with the specifications under which the cylinder was originally manufactured;

       (ii) Leak tested before and after assembly of the insulation jacket using a mass spectrometer detection system; and

       (iii) Tested for heat conductivity requirements.

       (3) Reconditioning of a DOT 4L welded insulated cylinder must be performed in accordance with paragraphs (a) and (b) of this section. Reconditioning applies to the work other than repair as described in paragraphs (c)(1) and (c)(2) of this section and that work is performed on parts other than the inner containment vessel (cylinder). Work to recondition a DOT 4L welded insulated cylinder includes the following:

       (i) The removal of either end of the insulation jacket.

       (ii) The replacement of the neck tube. At least a 13 mm (0.51 inch) piece of the original neck tube must be protruding above the cylinder's top end. The original weld attaching the neck tube to the cylinder must be sound, and the replacement neck tube must be welded to this remaining piece of the original neck tube.

       (iii) The replacement of material such as, but not limited to, the insulating material and the piping system within the insulation space with materials that are identical to those used in the original manufacture of the cylinder.

       (4) After reconditioning as described in paragraph (c)(3) of this section, the welded cylinder must be:

       (i) Pneumatically leak tested, to the closure point of all piping and gauging systems, to 90% of the service pressure or the relief valve set point, whichever is less;

       (ii) Leak tested before and after assembly of the insulation jacket using a mass spectrometer detection system; and

       (iii) Tested for heat conductivity requirements.

       * * * * *

       (e) * * *

       (1) The rebuilding of a DOT 4L welded insulated cylinder must be performed in conformance with paragraph (d) of this section. DOT-4 series cylinders requiring rebuild (e.g., when the inner vessel is compromised), as defined in Sec. 180.203, must do so in conformance with Sec. 180.211. DOT 4L cylinders which undergo procedures that are not defined as a rebuild in Sec. 180.203 are not subject to the requirements of Sec. 180.203(e). Rebuilding of a DOT-4L welded insulated cylinder also includes:

       (i) Substituting or adding material in the insulation space not identical to that used in the original manufacture of that cylinder, or

       (ii) Making a weld repair not to exceed 150 mm (5.9 inches) in length on the longitudinal seam of the cylinder or 300 mm (11.8 inches) in length on a circumferential weld joint of the cylinder.

       * * * * *

       0

   49. In Sec. 180.212, add paragraph (a)(3) to read as follows:

       Sec. 180.212 Repair of seamless DOT 3-series specification cylinders and seamless UN pressure receptacles.

       (a) * * *

       (3) If grinding is performed on a DOT 3-series cylinder or a seamless UN pressure receptacle, the following conditions apply after grinding has been completed. Grinding must not be used to remove arc burns from a cylinder as such a cylinder must be condemned:

       (i) Ultrasonic examination must be conducted to ensure that the wall thickness is not less than the minimum design requirement. The wall thickness must be measured in at least 3 different areas for every 10 square inches of grinding area.

       (ii) The cylinder must be requalified in conformance with Sec. 180.205 of this subpart.

       (iii) The cylinder must be marked in accordance with Sec. 180.213(f)(10) of this subpart to indicate compliance with this paragraph (a)(3).

       * * * * *

       0

   50. In Sec. 180.213, revise paragraphs (c) and (d)(2), and add paragraphs (f)(10), (f)(11), and (g) to read as follows:

       Sec. 180.213 Requalification markings.

       * * * * *

       (c) Requalification marking method. (1) The depth of requalification markings may not be greater than specified in the applicable specification. The markings must be made by stamping, engraving, scribing or other method that produces a legible, durable mark.

       (i) Requalification marks must begin at the top of the space provided, immediately to the right of the original manufacture date of the cylinder, as space allows. Subsequent retest dates must go immediately below the previous date, continuing down in sequential order to the bottom of the shoulder or area provided for marking. Retest marks must proceed further in columns to the right of the last column markings.

       (ii) Except as provided in part 178 of this subchapter, stamping on the sidewall is prohibited.

       (2) A cylinder used as a fire extinguisher (Sec. 180.209(j) of this subpart) may be marked by using a pressure sensitive label.

       (3) For a DOT 3HT cylinder, when stamped, the test date and RIN must be applied by low-stress steel stamps to a depth no greater than that prescribed at the time of manufacture. Stamping on the sidewall is not authorized.

       (4) For a composite cylinder, the requalification markings must be applied on a pressure sensitive label, securely affixed and overcoated with epoxy in a manner prescribed by the cylinder manufacturer, near the original manufacturer's label. Stamping of the composite surface is not authorized.

       Page 49021

       (d) * * *

       (2) A cylinder subject to the requirements of Sec. 171.23(a)(4) of this subchapter must be marked with the date and RIN in accordance with this paragraph (d) and paragraph (f)(11) of this section, or marked in accordance with the requalification authorized by the Associate Administrator in accordance with Sec. 171.23(a)(4)(i) of this subchapter.

       * * * * *

       (f) * * *

       (10) For designation of grinding with ultrasonic wall thickness examination, the marking is as illustrated in paragraph (d) of this section, except the ``X'' is replaced with the letter ``R''.

       (11) For designation of requalification of a foreign cylinder requalified in conformance with Sec. Sec. 171.23(a)(4) and 180.209(l) of this subchapter, the marking is as illustrated in paragraph (d) of this section, except that the ``X'' is replaced with the letters ``EX''.

       (g) Visual inspection requalification markings. Alternative to the marking requirements of paragraph (d) and (f)(5) of this section, each cylinder successfully passing a visual inspection only, in accordance with Sec. 180.209(g) of this subpart, may be marked with the visual inspection number (e.g., V123456) issued to a person performing visual inspections. An example of the manner in which the markings may be applied is as follows:

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

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

       V123 V123456

       03 14E 0314 E

       654

       0314 E V123456 V123456 0314E

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

       Where:

       ``03'' is the month of requalification (the additional numeral ``0'' is optional'')

       ``V123456'' is the RIN

       ``14'' is the year of requalification; and

       ``E'' to indicate visual inspection

       0

   51. In Sec. 180.215, revise paragraph (b) and (c)(2)(vii), and add (c)(3) to read as follows:

       Sec. 180.215 Reporting and record retention requirements.

       * * * * *

       (b) Requalification records. Daily records of visual inspection, pressure test, eddy current examination if required, and ultrasonic examination if permitted under a special permit, as applicable, 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. A single date may be used for each test sheet, provided each test on the sheet was conducted on that date. Ditto marks or a solid vertical line may be used to indicate repetition of the preceding entry for the following entries only: date; actual dimensions; manufacturer's name or symbol, if present; owner's name or symbol, if present; and test operator. Blank spaces may not be used to indicate repetition of a prior entry. A symbol may be used for the actual dimensions if there is a reference chart available at the facility that lists the actual dimensions of every symbol used. The records must include the following information:

       (1) Calibration test records. For each test to demonstrate calibration, the date; serial number of the calibrated cylinder; calibration test pressure; total, elastic and permanent expansions; and legible identification of test operator. The test operator must be able to demonstrate that the results of the daily calibration verification correspond to the hydrostatic tests performed on that day. The daily verification of calibration(s) may be recorded on the same sheets as, and with, test records for that date, or may be recorded on a separate sheet.

       (2) Pressure test and visual inspection records. The date of requalification; serial number; DOT-specification or special permit number; marked pressure; actual dimensions; manufacturer's name or symbol, if present; date of manufacture; owner's name or symbol, if present; gas service; result of visual inspection; actual test pressure; total, elastic and permanent expansions; percent permanent expansion; disposition, with reason for any repeated test, rejection or condemnation; and legible identification of test operator. For each cylinder marked pursuant to Sec. 173.302a(b)(5) of this subchapter, the test sheet must indicate the method by which any average or maximum wall stress was computed. Records must be kept for all completed, as well as unsuccessful tests. The entry for a repeated test must indicate the date of the earlier test, if conducted on a different day.

       (3) Wall stress. Calculations of average and maximum wall stress pursuant to Sec. Sec. 173.302a(b)(3) and 180.209(b)(1) of this subchapter, if performed.

       (4) Calibration certificates. The most recent certificate of calibration must be maintained for each calibrated cylinder, pressure indicating device, and expansion indicating device.

       (5) Eddy current examination records. (i) Records of eddy current inspection equipment must contain the following information:

       (A) Equipment manufacturer, model number, and serial number.

       (B) Probe description and unique identification (e.g., serial number, part number, etc.).

       (C) Specification of each standard reference ring used to perform the eddy current examination.

       (ii) Eddy current examination records must contain the following information:

       (A) DOT-specification or special permit number of the cylinder; manufacturer's name or symbol; owner's name or symbol, if present; serial number, and date of manufacture.

       (B) Identification of each standard reference ring used to perform the eddy current examination.

       (C) Name of test operator performing the eddy current examination.

       (D) Date of eddy current examination.

       (E) Acceptance/condemnation results (e.g., pass or fail).

       (F) Retester identification number.

       (c) * * *

       (2) * * *

       (vii) Results of a test on a cylinder, including test method, test pressure, total expansion, permanent expansion, elastic expansion, percent permanent expansion (permanent expansion may not exceed ten percent (10 percent) of total expansion), and volumetric capacity (volumetric capacity of a rebuilt cylinder must be within 3 percent of the calculated capacity);

       * * * * *

       (3) A record of grinding and ultrasonic examination in conformance with Sec. 180.212(a)(3) of this subpart must be completed for each cylinder on which grinding is performed. The record must be clear, legible, and contain the following information:

       (i) Name and address of the test facility, date of test report, and name or original manufacturer;

       (ii) Marks stamped on cylinder to include specification number, service pressure, serial number, symbol of manufacturer, and date of manufacture;

       (iii) Cylinder outside diameter and length in inches;

       (iv) Detailed map of where the grinding was performed on the cylinder; and

       (v) Wall thickness measurements in grind area in conformance with Sec. 180.212(a)(3)(i).

       * * * * *

       0

   52. In appendix C to part 180, the heading and paragraph 1 are revised to read as follows:

       Page 49022

       APPENDIX C TO PART 180--EDDY CURRENT EQUIPMENT REQUIREMENTS FOR INSPECTION OF DOT 3AL CYLINDERS MANUFACTURED OF ALUMINUM ALLOY 6351-T6

   1. Equipment calibration. Each facility performing an eddy current examination must develop, update, and maintain a written calibration procedure applicable to the test equipment it uses to perform eddy current examinations.

      * * * * *

      Issued in Washington, DC on July 11, 2016, under authority delegated in 49 CFR 1.97.

      William Schoonover,

      Acting Associate Administrator for Hazardous Materials Safety, Pipeline and Hazardous Materials Safety Administration.

      FR Doc. 2016-16689 Filed 7-25-16; 8:45 am

      BILLING CODE 4910-60-P