[Federal Register Volume 85, Number 248 (Monday, December 28, 2020)]
[Rules and Regulations]
[Pages 85380-85437]
[FR Doc No: 2020-26264]

Vol. 85

Monday,

No. 248

December 28, 2020

Part III

Department of Transportation

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

Pipeline and Hazardous Materials Safety Administration

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

49 CFR Parts 107, 171, 173, et al.

Hazardous Materials: Miscellaneous Amendments Pertaining to DOT-
Specification Cylinders; Final Rule

Federal Register / Vol. 85 , No. 248 / Monday, December 28, 2020 /
Rules and Regulations

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

DEPARTMENT OF TRANSPORTATION

Pipeline and Hazardous Materials Safety Administration

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

[Docket No. PHMSA-2011-0140 (HM-234)]
RIN 2137-AE80

Hazardous Materials: Miscellaneous Amendments Pertaining to DOT-
Specification Cylinders

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

ACTION: Final rule.

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

SUMMARY: PHMSA is amending the Hazardous Materials Regulations (HMR) 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 agency review of compressed gas cylinder regulations.
Specifically, PHMSA is incorporating by reference or updating the
references to several Compressed Gas Association publications, amending
the filling requirements for compressed and liquefied gases, expanding
the use of salvage cylinders, and revising and clarifying the
manufacture and requalification requirements for cylinders.

DATES:
    Effective date: January 27, 2021.
    Incorporation by reference date: The incorporation by reference of
certain publications listed in this rule is approved by the Director of
the Federal Register as of January 27, 2021. The incorporation by
reference of other publications listed in this rule were previously
approved by the Director of the Federal Register as of January 1, 2004
(ASTM E 8-99 and Welding Aluminum: Theory and Practice, Fourth Edition)
and May 11, 2020 (Transport Canada TDG Regulations).
    Compliance Date: Unless otherwise specified, compliance with the
amendments adopted in this final rule is required beginning December
28, 2021.

FOR FURTHER INFORMATION CONTACT: Eamonn Patrick, 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<PHONE_NUMBER>.

SUPPLEMENTARY INFORMATION:
I. Executive Summary
II. ANPRM Background
III. NPRM Background
IV. Petitions for Rulemaking and Comments Received
V. Special Permits and Comments Received
VI. Agency Initiated Editorial Corrections
VII. Section-by-Section Review
VIII. Regulatory Analyses and Notices
    A. Statutory/Legal Authority for This Final Rule
    B. Executive Order 12866 and DOT Policies and Procedures for
Rulemakings
    C. Executive Order 13771
    D. Executive Order 13132
    E. Executive Order 13175
    F. Regulatory Flexibility Act, Executive Order 13272, and DOT
Procedures and Policies
    G. Paperwork Reduction Act
    H. Regulation Identifier Number (RIN)
    I. Unfunded Mandates Reform Act of 1995
    J. Environmental Assessment
    K. Privacy Act
    L. Executive Order 13609 and International Trade Analysis
    M. National Technology Transfer and Advancement Act

I. Executive Summary

    Cylinders filled with a Class 2 hazardous material (gas) or other
hazardous materials and offered for transportation must comply with
various requirements 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 repair, maintenance, and periodic
requalification of cylinders. Additionally, cylinders must meet other
requirements in the HMR, such as regulations that address the modal
requirements on cylinders in transportation including general handling,
loading, unloading, and stowage.
    PHMSA (also referred to herein as ``we'' or ``us''), in response to
petitions for rulemaking submitted by stakeholders and an Agency
initiated review of the regulations, is making 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; and revising
and clarifying the manufacture and requalification requirements for
cylinders. This final rule is also presenting minor and miscellaneous
regulatory editorial corrections. These revisions are collectively
intended to result in a net reduction of regulatory burdens while
maintaining or enhancing the existing level of safety of hazardous
materials transported in cylinders. Based on the regulatory impact
analysis conducted in support of this final rule, PHMSA estimates that
adoption of this final rule will result in net cost savings of
approximately $.70 million over 10 years, or $70,000 annualized
(undiscounted).

II. ANPRM Background

    On May 29, 2012, PHMSA published an Advance Notice of Proposed
Rulemaking (ANPRM) to obtain public comment from those likely to be
affected by the possible adoption of ten petitions for rulemaking and
three special permits (SP) into the HMR (77 FR 31551). Commenters
included cylinder manufacturers, cylinder requalifiers, independent
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. The ANPRM proposed
adopting the petitions for rulemaking and special permits to 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 a 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 supportive for all of the
petitions, with the exception of P-1515. PHMSA received four comments
regarding the 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 Comment Docket No.
----------------------------------------------------------------------------------------------------------------
                          Company                                               Docket ID No.
----------------------------------------------------------------------------------------------------------------
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 (CGA)...........................  PHMSA-2011-0140-0005
                                                             PHMSA-2011-0140-0012
                                                             PHMSA-2011-0140-0013
                                                             PHMSA-2011-0140-0020
Council on Safe Transportation of Hazardous Articles, Inc.   PHMSA-2011-0140-0026
 (COSTHA).
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
----------------------------------------------------------------------------------------------------------------

    Please see the HM-234 notice of proposed rulemaking (NPRM)
published on July 26, 2016 (81 FR 48978) for a detailed discussion of
comments made to the ANPRM.

III. NPRM Background

    On July 26, 2016, PHMSA published an NPRM to obtain public comment
on changes proposed to the HMR (81 FR 48978). The NPRM addressed 20
total petitions, one special permit, and several PHMSA-initiated
editorial changes intended to clarify HMR requirements. After
publication of the NPRM, PHMSA received comments from 44 stakeholders
on the proposed changes. A table of commenters is shown in Table 2
below:

                           Table 2--NPRM Commenters and Associated Comment Docket No.
----------------------------------------------------------------------------------------------------------------
                          Company                                               Docket ID No.
----------------------------------------------------------------------------------------------------------------
Alaska Airlines............................................  PHMSA-2011-0140-0036
Amerex.....................................................  PHMSA-2011-0140-0061
AmeriGas Propane, L.P......................................  PHMSA-2011-0140-0066
Amtrol.....................................................  PHMSA-2011-0140-0063
                                                             PHMSA-2011-0140-0058
Bancroft Hinchey Inc.......................................  PHMSA-2011-0140-0071
Compressed Gas Association (CGA)...........................  PHMSA-2011-0140-0052
Council on Safe Transportation of Hazardous Articles         PHMSA-2011-0140-0083
 (COSTHA).
CTC (Certified Training Co.)...............................  PHMSA-2011-0140-0057
                                                             PHMSA-2011-0140-0042
Danko Emergency Equipment Co...............................  PHMSA-2011-0140-0044
Dow Chemical Company.......................................  PHMSA-2011-0140-0060
Entegris...................................................  PHMSA-2011-0140-0082
FIBA.......................................................  PHMSA-2011-0140-0074
                                                             PHMSA-2011-0140-0041
Fike Corporation...........................................  PHMSA-2011-0140-0077
Fire Suppression Systems Association (FSSA)................  PHMSA-2011-0140-0047
Firehouse Hydro Sales and Service..........................  PHMSA-2011-0140-0067
Ford Motor Company.........................................  PHMSA-2011-0140-0055
Galiso Incorporated........................................  PHMSA-2011-0140-0062
Hidroprob S.A..............................................  PHMSA-2011-0140-0079
HMT Associates, LLC........................................  PHMSA-2011-0140-0049
Honeywell..................................................  PHMSA-2011-0140-0084
Hydro-Test Products Inc....................................  PHMSA-2011-0140-0033
Independent Cylinder Training (ICT)........................  PHMSA-2011-0140-0068
Janus Fire Systems.........................................  PHMSA-2011-0140-0069
Kidde-Fenwal, Inc..........................................  PHMSA-2011-0140-0065
Manchester Tank............................................  PHMSA-2011-0140-0050
Wesley Scott...............................................  PHMSA-2011-0140-0080
Chart, Inc.................................................  PHMSA-2011-0140-0078
Guardian Services, Inc.....................................  PHMSA-2011-0140-0072
Joshua Blake...............................................  PHMSA-2011-0140-0059
Jeff Elliot................................................  PHMSA-2011-0140-0043
David Felkins..............................................  PHMSA-2011-0140-0035
W Andrews..................................................  PHMSA-2011-0140-0034

Katherine Bowman...........................................  PHMSA-2011-0140-0032
National Association of Fire Equipment Distributors........  PHMSA-2011-0140-0053
National Propane Gas Association...........................  PHMSA-2011-0140-0070
Noble Gas Solutions........................................  PHMSA-2011-0140-0045
Northeast Pressure Vessel Testing..........................  PHMSA-2011-0140-0046
Praxair....................................................  PHMSA-2011-0140-0073
Quality Safety Solutions, LLC..............................  PHMSA-2011-0140-0040
Scuba Do...................................................  PHMSA-2011-0140-0081
Steve Gentry...............................................  PHMSA-2011-0140-0086
The Chemours Company FC, LLC...............................  PHMSA-2011-0140-0054
Thunderbird Cylinder.......................................  PHMSA-2011-0140-0037
Worthington Cylinder.......................................  PHMSA-2011-0140-0064
----------------------------------------------------------------------------------------------------------------

    Most comments addressed more than one change proposed in the NPRM.
The comments are discussed below in the context of each petition or
other proposed changes it addresses.

IV. Petitions for Rulemaking and Comments Received

    Table 3 lists the petitions included in the docket for this
proceeding. The NPRM addressed 20 total petitions. The table below
provides the petition number, the petitioner's name, the docket number
on www.regulations.gov, a summary of the request(s), the affected 49
CFR sections, whether PHMSA proposed to adopt the petition in the NPRM,
and the decision to adopt, adopt in part, or not adopt the petition in
this final rule.

                                                                Table 3--Petition Summary
--------------------------------------------------------------------------------------------------------------------------------------------------------
    Petition No.         Petitioner               Docket No.                  Summary           Affected sections  Proposed to adopt?       Adopted?
--------------------------------------------------------------------------------------------------------------------------------------------------------
P-1499.............  Compressed Gas      PHMSA-2007-28485...........  Replace the              Sec.  Sec.          Proposed to adopt.  Adopted.
                      Association.                                     incorporated by          171.7; 172.102
                                                                       reference (IBR)          (SP 338);
                                                                       Seventh Edition of the   173.3(d)(9);
                                                                       CGA C-6 Standards for    173.198(a);
                                                                       Visual Inspection of     180.205(f)(1);
                                                                       Steel Compressed Gas     180.209(c),
                                                                       Cylinders with the       (b)(1)(iii), (d),
                                                                       revised Tenth Edition    (f), (g), (m);
                                                                       and update the           180.211(d)(1)(ii)
                                                                       appropriate references   ; 180.411(b);
                                                                       throughout the HMR.      180.510(c).
P-1501.............  Compressed Gas      PHMSA-2007-28759...........  Revise the               Sec.  Sec.          Proposed to adopt   Adopted in part.
                      Association.                                     specification            178.50, 178.51,     in part.
                                                                       requirements for 4B,     178.61, 178.68.
                                                                       4BA, 4BW, and 4E
                                                                       cylinders to provide
                                                                       clarity.
P-1515.............  Certified Training  PHMSA-2008-0101............  Adopt changes to the     Sec.  Sec.          Proposed to adopt,  Adopted in part.
                      Company.                                         requalification          180.203, 180.205,   except those
                                                                       process designed to      180.207, 180.209,   changes not
                                                                       clarify the              180.211, 180.212,   necessary because
                                                                       regulations in the       180.213, and        of incorporation
                                                                       event CGA Standard C-    180.215 and         by reference of
                                                                       1, Methods of Pressure   appendices C and    CGA C-1 under P-
                                                                       Testing Compressed Gas   E to part 180.      1626.
                                                                       Cylinders, is not
                                                                       incorporated.
P-1521.............  Compressed Gas      PHMSA-2008-0152............  Allow the use of labels  Sec.                Proposed to adopt.  n/a; addressed by
                      Association.                                     described in CGA C-7-    172.400a(a)(1)(i).                      another
                                                                       2004 on a cylinder                                               rulemaking.
                                                                       contained in an
                                                                       overpack.
P-1538.............  The Wicks Group,    PHMSA-2009-0138............  Allow Sec.               Sec.  Sec.          Not proposed to     Not adopted.
                      representing                                     173.306(a)(1) to         171.8,              adopt.
                      Jetboil Inc.                                     permit camping stove     173.306(a)(1).
                                                                       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, 3AA, 3AL   Sec.   180.209(a).  Not proposed to     Not adopted.
                                                                       cylinders in Division                        adopt.
                                                                       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.   178.35(f)..  Proposed to adopt.  Adopted.
                      Association.                                     manufactured 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 used as  Sec.   173.309(a).  Proposed to adopt.  Adopted in part.
                      Services, Inc.                                   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 maximum       Sec.                Not proposed to     Not adopted.
                      Chemicals, Inc.                                  permitted filling        173.304a(a)(2).     adopt. Addressed
                                                                       densities for carbon                         by revisions made
                                                                       dioxide and nitrous                          under rulemaking
                                                                       oxide to include                             HM-233F [81 FR
                                                                       70.3%, 73.2%, and                            3635].
                                                                       74.5% in DOT 3A, 3AA,
                                                                       3AX, 3AAX, and 3T
                                                                       cylinders.
P-1563.............  Regulatory Affairs  PHMSA-2010-0208............  Authorize an             Sec.                n/a; We asked for   Not adopted.
                      Management                                       ``overpack'' as a        173.301(a)(9).      further comment.
                      Center--3M                                       strong outer package
                      Package                                          for cylinders listed
                      Engineering,                                     in the section, except
                      Global Dangerous                                 aerosols ``2P'' and
                      Goods.                                           ``2Q,'' marked with
                                                                       the phrase ``inner
                                                                       packagings conform to
                                                                       the prescribed
                                                                       specifications''.
P-1572.............  Barlen and          PHMSA-2011-0017............  Revise the filling       Sec.  Sec.          Proposed to adopt,  Adopted, in part.
                      Associates, Inc.                                 ratio for liquefied      173.301(g)(1)(ii)   in part.
                                                                       compressed gases in      and 173.312.
                                                                       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 burst        Sec.  Sec.          Proposed to adopt.  Adopted.
                                                                       pressure of the          173.301(f)(4),
                                                                       rupture disc on a        173.302(f)(2),
                                                                       cylinder ``shall not     173.304(f)(2).
                                                                       exceed 80% of the
                                                                       minimum cylinder burst
                                                                       pressure and shall not
                                                                       be less than 105% of
                                                                       the cylinder test
                                                                       pressure'' for DOT 39
                                                                       cylinders containing
                                                                       oxidizing gas
                                                                       transported by
                                                                       aircraft.
P-1582.............  Water Systems       PHMSA-2011-0135............  Revise the limited       Sec.   173.306(g).  Proposed to adopt.  Adopted.
                      Council.                                         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).
P-1592.............  Compressed Gas      PHMSA-2012-0173............  IBR CGA S-1.1, 2011      Sec.  Sec.          Proposed to adopt.  Adopted.
                      Association.                                     Pressure Relief Device   173.301(c), (f)
                                                                       Standards, Part 1,       and (g),
                                                                       Cylinder for             173.302a(c),
                                                                       Compressed Gas,          173.304a(e),
                                                                       Fourteenth Edition.      178.75(f).
P-1596.............  Chemically          PHMSA-2012-0200............  Add Class 4 and Class 5  Sec.   173.3(d)(1)  Proposed to adopt.  Adopted.
                      Speaking, LLC.                                   hazardous materials to
                                                                       the hazard classes in
                                                                       an authorized salvage
                                                                       cylinders.
P-1622.............  Worthington         PHMSA-2013-0210............  Restrict the internal    Sec.                Proposed to adopt.  Adopted in part.
                      Cylinder.                                        volume of hazardous      173.304a(a)(2)
                                                                       materials shipped in a   and (3).
                                                                       DOT-specification 39
                                                                       cylinder to not exceed
                                                                       75 cubic inches.
P-1626.............  Compressed Gas      PHMSA-2013-0265............  IBR CGA C-1-2009,        Sec.  Sec.          Proposed to adopt.  Adopted.
                      Association.                                     Methods for Pressure     171.7, 178.36,
                                                                       Testing Compressed Gas   178.37, 178.38,
                                                                       Cylinders, Tenth         178.39, 178.42,
                                                                       Edition (C-1, 2009) as   178.44, 178.45,
                                                                       a reference in 49 CFR,   178.46, 178.47,
                                                                       and provide for          178.50, 178.51,
                                                                       specific language for    178.53, 178.55,
                                                                       sections 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-3-2005,        Sec.  Sec.          Proposed to adopt.  Adopted.
                      Association.                                     Reaffirmed 2011,         171.7, 178.47,
                                                                       Standards for Welding    178.50, 178.51,
                                                                       on Thin-Walled, Steel    178.53, 178.55,
                                                                       Cylinders, Seventh       178.56, 178.57,
                                                                       Edition.                 178.58, 178.59,
                                                                                178.60, 178.61,
                                                                                178.65, 178.68,
                                                                                180.211.

P-1629.............  Compressed Gas      PHMSA-2014-0012............  IBR CGA C-14-2005,       Sec.  Sec.          Proposed to adopt.  Adopted.
                      Association.                                     Reaffirmed 2010,         171.7, 173.301,
                                                                       Procedures for Fire      173.323.
                                                                       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.          Proposed to adopt.  Not adopted.
                      Association.                                     ``recondition'' for      180.203 and
                                                                       DOT-4L welded            180.211(c) and
                                                                       insulated cylinders      (e).
                                                                       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.
--------------------------------------------------------------------------------------------------------------------------------------------------------

P-1499

    The Compressed Gas Association (CGA) submitted P-1499 requesting
that PHMSA incorporate by reference the Tenth Edition of its
publication C-6, dated 2005, Standards for Visual Inspection of Steel
Compressed Gas Cylinders (CGA C-6), replacing the Seventh Edition, and
update the appropriate references throughout the HMR. The Tenth Edition
of the CGA C-6 provides enhanced guidance for cylinder requalifiers--
including guidance on the inspection of Multiple-Element Gas Containers
(MEGCs) and thread inspection for cylinders used in corrosive gas
service--and clarifies maximum allowable depths and measuring
techniques for various types of corrosion.
    PHMSA agrees that the CGA C-6 Tenth Edition provides improved and
updated guidance on inspecting MEGCs. After the submission of this
petition, the Eleventh Edition of the CGA C-6, dated 2013, was made
available. PHMSA, therefore, proposed in the NPRM to update the
incorporated by reference version of CGA C-6 to the Eleventh Edition.
PHMSA determined that the changes from the Tenth to the Eleventh
Editions were minor and improved safety, while not imposing any
additional burdens on the regulated community.
    Comments. Bancroft Hinchey, Worthington Cylinder, the National
Association of Fire Equipment Distributors (NAFED) and CGA submitted
comments supporting incorporation by reference of the Eleventh Edition
of CGA C-6. Thunderbird Cylinder submitted a comment requesting
revisions to CGA publication C-6.1, Standards for Visual Inspection of
High Pressure Aluminum Compressed Gas Cylinders and CGA publication C-
11, Recommended Practices for Inspection of Compressed Gas Cylinders at
Time of Manufacture.
    PHMSA response. In this final rule, PHMSA is incorporating by
reference the Eleventh Edition of the CGA C-6, as proposed. The Tenth
Edition of the CGA C-6 provides enhanced guidance for cylinder
requalifiers--including guidance on the inspection of Multiple-Element
Gas Containers (MEGCs) and thread inspection for cylinders used in
corrosive gas service--and clarifies maximum allowable depths and
measuring techniques for various types of corrosion. PHMSA has
determined that the changes from the Tenth to the Eleventh Editions
were minor and improved safety, while not imposing any additional
burdens on the regulated community. The Eleventh edition of CGA C-6 is
available for purchase online and will be available for public
inspection at the Hazardous Material Information Center after
publication of the final rule.
    Thunderbird Cylinder's comment is beyond the scope of this
rulemaking, but we encourage Thunderbird Cylinder or other interested
parties to reach out to CGA regarding potential revisions to its
publications and then, if warranted, to submit separate petitions for
rulemaking requesting that PHMSA incorporate by reference the revised
versions of CGA C-6.1 and C-11, respectively.

P-1501

    CGA submitted P-1501 requesting that PHMSA revise the manufacturing
requirements for DOT 4B, 4BA, 4BW, and 4E specification cylinders. CGA
contends in their petition that the DOT 4-series welded cylinder
manufacturing specification standards in the HMR are unclear in some
respects and result in varied interpretations of what is required of
manufacturers by both manufacturers and enforcement personnel. CGA
states in the petition that their proposed changes do not present a
significant economic impact to any single manufacturer or user, yet
will enhance regulatory clarity, promote consistent manufacturing
practices, and create greater uniformity between the specifications for
DOT 4-series cylinders and the requirements for welded cylinders found
in International Organization for Standardization (ISO) Standard 4706-
1, Gas cylinders--Refillable welded steel cylinders-Part 1: Test
pressure 60 bar and below (ISO 4706-1), which is referenced in the UN
Model Regulations. The HMR currently incorporates ISO 4706-1 into Sec.
178.71 as an authorized standard for the design and construction of UN
pressure receptacles.
    Comments. CGA submitted a comment reiterating their support for
adoption of P-1501. Bancroft Hinchey submitted a comment supporting all
proposed changes to the manufacturing specifications in Sec. Sec.
178.36-178.70.
    A summary of the specific changes proposed by P-1501, the comments
received relative to the proposed changes, if any, and PHMSA's position
and/or action are detailed below:
    (1) Revise the requirements for DOT-specification 4B, 4BA, 4BW, and
4E cylinders in Sec. Sec.  178.50(b), 178.51(b), 178.61(b), and
178.68(b), respectively, to ensure material compositions and the heat
treatment are within the specified tolerances and are of uniform
quality as follows: (1) Require a record of intentionally-added
alloying elements, and (2) require materials manufactured outside of
the United States to have a ladle analysis confirmed by a check
analysis.
    Comments. We did not receive any comments regarding either
proposal.
    PHMSA response. The provision regarding materials manufactured
outside the United States having a ladle analysis confirmed by a check
analysis is not necessary because Sec.  178.35(c)(2) requires
inspectors to verify that the material of construction meets the
requirements of the applicable specification by: (1) Making a chemical
analysis of each heat of material; (2) obtaining a certified chemical
analysis

from the material manufacturer for each heat of material (a ladle
analysis is acceptable); or (3) if an analysis is not provided for each
heat of material by the material manufacturer, by making a check
analysis of a sample from each coil, sheet, or tube. However, we do
believe a record of intentionally added alloying elements will be
useful for ensuring material compositions are within the specified
tolerances. A cylinder made of material within specified tolerances is
less susceptible to deterioration or failure from the wear and tear on
a cylinder from pressure cycling and exposure to pressurized gases.
    PHMSA, therefore, is adopting the requirement for manufacturers to
maintain a record of intentionally added alloying elements, as
proposed.
    (2) Revise the pressure tests for DOT-specification 4B, 4BA, 4BW,
and 4E cylinders in Sec. Sec.  178.50(i), 178.51(i), 178.61(i), and
178.68(h), respectively, to permit use of the volumetric expansion
test, a hydrostatic proof pressure test or a pneumatic proof pressure
test.
    Given the added risk associated with pneumatic testing (i.e., using
pressurized gas for testing) and that there are suitable alternatives
to determine whether a cylinder has a leak at the time of manufacture,
PHMSA did not propose to permit the use of pneumatic proof pressure
testing in the NPRM.
    Comments. Fike Corporation, the National Propane Gas Association
(NPGA), AmeriGas Propane, Amtrol, Worthington Cylinder (Worthington)
and Manchester Tank (Manchester) submitted comments opposing PHMSA's
decision to not permit the use of pneumatic proof pressure testing.
Bancroft Hinchey and NAFED submitted comments supporting our decision
to not permit the use of pneumatic proof pressure testing.
    PHMSA response. This final rule allows manufacturers to conduct
pneumatic proof pressure tests, when proof pressure tests are
authorized in part 178, subpart C. PHMSA is convinced by the comments
from Fike, NPGA, Amerigas, Amtrol, Worthington, and Manchester that
manufacturers currently account for the additional risks created by
pneumatic proof pressure testing. PHMSA would like to emphasize that
pneumatic proof pressure test systems can present increased risks to
test personnel due to the amount of energy stored in a cylinder filled
to test pressure with a gas. This stored energy, if released due to a
cylinder failure, is sufficient to cause serious injury or death.
Manufacturers must take this risk into account and develop systems to
prevent the death or injury of their employees in the event of a
catastrophic cylinder rupture at test pressure. The use of additional
safety equipment such as blast shields, test cages, etc., is advisable
to prevent possible injury to testing personnel and equipment.
    (3) Revise the physical and flattening tests and retest criteria
for DOT-specification 4B, 4BA, 4BW, and 4E cylinders in Sec. Sec.
178.50, 178.51, 178.61, and 178.68, respectively, for consistency.
These revisions would clarify the location on the cylinder from which
the test specimens are removed.
(a) Elongation Criteria
    Fike Corporation submitted a comment requesting that we review the
proposed revisions to the elongation criteria for specimens taken from
DOT 4B, 4BA and 4BW cylinders under Sec. Sec.  178.50, 178.51, and
178.61, based on its opinion that we should not revise the criteria at
this time.
    PHMSA response. We agree with Fike Corporation's comment that PHMSA
should not revise the elongation criteria. In reviewing the proposed
changes based on comments received, we solicited comment from Steve
Gentry, the original submitter of the elongation criteria modification
to CGA, to provide additional justification for changing the elongation
requirement to 20 percent for all specimens, regardless of gauge length
in making our final determination on the proposed language based on
CGA's petition.
    Mr. Gentry justified the requested change based on international
harmonization and consistency with other elongation criteria
calculations in the HMR. However, PHMSA does not believe these
justifications warrant making the requested change. First, changing the
elongation requirement will not assist in harmonizing with
international standards at this time. A review of Transport Canada
standard B339-18 shows that Canada has not revised cylinder
manufacturing standards to require a 20 percent elongation for all
specimens (e.g. see CSA B339-18 5.8.3). Second, we believe that
changing the elongation criteria will introduce confusion to the
detriment of compliance with no measurable safety benefit. Current
elongation criteria are well understood in the industry and we do not
believe we have enough information at this time to make the requested
change.
    Additionally, in response to Mr. Gentry's final justification, we
do not believe that the current elongation criteria for two inch
specimens conflicts with the ``24t'' formula in Sec. Sec.
178.50(k)(2), 178.51(j)(2), and 178.61(k)(2). In Sec. Sec.
178.50(k)(2), 178.51(j)(2), and 178.61(k)(2), cylinder manufacturers
may choose to conduct elongation tests on cylinder specimens with a set
length of eight inches or two inches with width not over 1.5 inches, or
use a cylinder specimen with a gauge length of 24 times the thickness
of the wall with width not over 6 times the thickness, commonly known
as a ``24t'' gauge length. Cylinder specimens with a gauge length of 2
inches must achieve elongation of at least 40 percent, while all other
gauge lengths (i.e., the 24t gauge length) must achieve an elongation
of at least 20 percent. Mr. Gentry identified several specific
instances where a cylinder manufacturer utilizing the 24t gauge length
option would use a calculated gauge length very close to 2 inches (e.g.
a cylinder with a wall thickness of .0835 inches would, using the 24t
formula, have a specimen 2.004 inches long) which would be subject to
an elongation requirement of 20 percent, rather than the 40 percent
requirement for a standard 2-inch gauge specimen. Mr. Gentry believes
that the 20 percent elongation requirement for the 2.004 inch x .501-
inch specimen calculated using the 24t method conflicts with the 40
percent elongation requirement for the 2 inch x 1\1/2\ inch specimen.
    A direct elongation comparison between specimens with 24t gauge
length (GL) x 6t wide, and 2'' GL x 1\1/2\'' width, however, is not
valid because the load resisting cross-sectional areas are not the same
even when nearly the same gauge lengths are used for both specimens.
Essentially the ``24t'' gauge length specimen and the 2-inch specimen
cannot be directly compared because their cross-sectional areas are
different; therefore, it is correct to have different elongation
criteria even when the ``24t'' specimen is very nearly 2 inches long.
PHMSA acknowledges that there may be room for improvement of the DOT 4-
series cylinder elongation criteria associated with the physical and
flattening tests and plans to continue reviewing the criteria for
possible changes.
(b) Non-Destructive Examination
    Fike Corporation submitted an additional comment opposing the
proposed requirement to examine circumferential welds in addition to
longitudinal welds using radioscopic or radiographic examination under
proposed Sec.  178.61(f), indicating that it believes this is a
significant change. Regarding Fike Corporation's comments on
radioscopic or radiographic examination applicability, we agree.

The current requirements in Sec.  178.61(d)(3)(ii) require radioscopic
or radiographic examination of the longitudinal weld only, except in
the case of spot radioscopy or radiography. It was not our intent to
impose new weld radioscopy or radiography requirements in this final
rule. Therefore, in this final rule we are modifying the requirements
in Sec.  178.61(d)(5) to clarify that radioscopic or radiographic
examination of the circumferential weld is not required, except as part
of spot radioscopy or radiography. Additionally, we are moving the
proposed radiography examination language from Sec.  178.61(f) to Sec.
178.61(d)(5) in order to improve the organization of, and therefore,
understanding of the section.
(c) Specimen Test Failure
    In the NPRM, we proposed to amend the rejected cylinder paragraphs
for 4B, 4BA and 4E cylinders to align them with the provisions for 4BW
cylinders. Specifically, we proposed to add a provision to Sec. Sec.
178.50(n), 178.51(m), and 178.68(m) that would allow two additional
specimens to be selected from the same lot and subjected to the
prescribed test. If either of the two specimens failed the test, the
entire lot would be rejected.
    No rationale was presented in P-1501 for this change. Moreover, we
received no comments on these specific provisions. We do not believe
that a change to cylinder rejection criteria is warranted at this time
because we do not have enough supporting information to justify the
change, and therefore we will not amend the rejected cylinder language
in this final rule. We may consider this action in a future rulemaking.
    (4) Revise Sec. Sec.  178.50(n), 178.51(n), and 178.61(o), and
178.68, respectively, for DOT-specification 4B, 4BA, 4BW, and 4E
cylinders to permit marking on the footring for cylinders with water
capacities up to 30 pounds, instead of 25 pounds.
    We received no comments regarding this item and are adopting the
revision as proposed.
    (5) Add additional options for the location of markings on DOT 4E
cylinders in Sec.  178.68.
    We received no comments regarding this item and are adopting the
addition as proposed.
    (6) Determination of Expansion.
    Related to P-1501, Worthington Cylinder submitted a comment
requesting that we eliminate the requirement to determine expansion for
non-spherical 4B, 4BA, and 4BW cylinders at time of manufacture. This
comment is beyond the scope of this rulemaking. We encourage
Worthington Cylinder or other interested parties to submit petitions on
this issue.
    (7) Correction.
    In the review of the NPRM, PHMSA determined that we inadvertently
replaced the word ``rejected'' with ``condemned'' in several places in
Sec. Sec.  178.50, 178.51, 178.61, and 178.68. This was not our intent.
In this final rule, we will maintain the HMR's existing language for
cylinders rejected during manufacture.

P-1515

    The Certified Training Company (CTC) submitted P-1515 requesting
that PHMSA make numerous revisions to the requirements for the
requalification of DOT-specification cylinders found in 49 CFR part
180, subpart C. Part 180, subpart C includes definitions for terms used
in the subpart, references to CGA publications for the visual
inspection of cylinders, and requirements for hydrostatically testing
cylinders including methods to ensure the accuracy of test equipment.
Many changes proposed in P-1515 were intended to align the requirements
in part 180, subpart C with an industry standard for the
requalification of gas cylinders known as CGA C-1, Methods for Pressure
Testing Compressed Gas Cylinders (CGA C-1). CTC acknowledged that the
preferred outcome would be to incorporate by reference CGA C-1 into
part 180, subpart C, but the petitioner presented an option whereby
PHMSA could adopt many of the provisions of CGA C-1 into the current
structure of the HMR without incorporating CGA C-1.
    Many of P-1515's proposed changes were only requested in the event
that PHMSA chose not to adopt P-1626. P-1626 requested that PHMSA
incorporate by reference CGA C-1 into part 180, subpart C. In the NPRM,
PHMSA proposed to incorporate CGA C-1 (Eleventh Edition) into part 180,
subpart C in addition to the numerous changes suggested by P-1515. CTC,
along with numerous others, submitted extensive comments regarding this
action. In this final rule, we will incorporate the Eleventh Edition of
CGA C-1 for the requalification of compressed gas cylinders, which
renders many of P-1515's proposed changes moot. Please see our
discussion of P-1626 for additional discussion of CGA C-1 and revisions
to the structure of part 180, subpart C.
(1) Comments Related to the Incorporation by Reference of CGA C-1
(a) Definitions
    Certified Training Company (CTC) and Bancroft Hinchey submitted
comments opposing our proposed inclusion of additional definitions for
cylinder requalification terms in Sec.  180.203, which were intended to
bring the HMR into alignment with CGA C-1. CTC also suggested we delete
other long-standing definitions in Sec.  180.203 because they did not
align with CGA C-1's definitions.
    PHMSA response. We agree with CTC and Bancroft Hinchey's comments
to remove the definitions of ``Accuracy,'' ``Accuracy grade,'' ``Actual
test pressure,'' ``Calibrated cylinder,'' ``Defect,'' ``Elastic
expansion,'' ``Error,'' ``Master gauge,'' ``Percent permanent
expansion,'' ``Permanent expansion,'' ``Reference gauge,''
``Rejected,'' ``Service pressure,'' ``Test pressure,'' ``Total
expansion,'' ``Visual inspection,'' and ``Volumetric expansion test''
from Sec.  180.203. We are incorporating by reference CGA C-1 into the
HMR and these terms are all defined in this industry standard; thus,
codification of the definitions in Sec.  180.203 is redundant and this
provides us an opportunity to reduce the size of the HMR. However,
PHMSA has decided to keep the definition of ``condemn'' because Sec.
180.205(i) will continue to discuss condemnation criteria in greater
detail than CGA C-1 does and we believe maintaining the definition in
Sec.  180.203 will increase clarity for cylinder requalifiers.
(b) Incorporation of CGA C-1 Into Sec.  180.205(g)
    CTC and Bancroft Hinchey noted that the NPRM did not incorporate by
reference CGA C-1 into Sec.  180.205(g), which was PHMSA's stated
intent in the NPRM preamble. Section 180.205(g) is a crucial paragraph
for cylinder requalifications that contains instructions on how to
conduct the pressure test that is used to requalify a cylinder for
future use or condemn it. By incorporating CGA C-1 into Sec.
180.205(g), we will require cylinder requalifiers to comply with the
instructions in CGA C-1 when conducting pressure tests. These
instructions offer more guidance and include helpful diagrams and
examples that decrease compliance burdens compared to the current
instructions in Sec.  180.205(g).
    PHMSA response. We agree with CTC and Bancroft Hinchey's comments.
It was our intent to incorporate CGA C-1 for the requalification of DOT

specification cylinders, therefore, in this final rule we are including
a reference to CGA C-1 (Eleventh Edition) in Sec.  180.205(g).
(c) Streamlining of Existing Regulatory Text
    CTC and CGA noted that since we proposed to adopt P-1626, there was
an opportunity to streamline the HMR's cylinder requalification
instructions significantly by revising Sec.  180.205(g) to require
compliance with CGA C-1, rather than maintaining the existing
instructions for pressure tests. CTC and CGA commented that maintaining
two sets of instructions would generate confusion and frustration.
    PHMSA response. We agree with CTC and CGA's comments to revise
existing Sec.  180.205(g). This final rule removes the existing
language in the HMR on conducting volumetric expansion testing from
Sec.  180.205(g) and replaces it with instructions to conduct
requalification in accordance with CGA C-1. These revisions will help
to reduce confusion and improve compliance without increasing burdens
on the regulated community while meeting our stated intent in the NPRM
to adopt the CGA C-1 standard as the industry standard for performance
of inspection and testing for requalification and continued service of
cylinders.
(d) Accuracy Requirements
    In the NPRM, PHMSA proposed to align with ISO requirements by
requiring the pressure indicating device (PID) to meet ``Industrial
Class 1 (1% deviation from the end value).'' CGA, Hidroprob
SA, Bancroft Hinchey, and Galiso identified this change as problematic
because it conflicts with the accuracy grade requirements for PIDs
found in CGA C-1.
    PHMSA response. Hidroprob S.A., Bancroft Hinchey, Galiso, and CGA's
comments regarding device accuracy are correct, and contributed to our
decision to not adopt the proposed changes in Sec.  180.205(g) and
simplify requirements by adopting CGA C-1 into the section. In this
final rule, we will not adopt the proposed changes to device accuracy
in Sec.  180.205(g). In this final rule, we will maintain the HMR's
current PID accuracy requirements in Sec.  180.205(g)(3)(i). Voluntary
compliance with CGA C-1 <IP_ADDRESS> is authorized and will meet the HMR's
accuracy requirements for PIDs used for cylinder requalification, as
will the practice of demonstrating accuracy through maintenance of a
calibration certificate showing the gauge has been certified to meet
the accuracy requirements at lower points. See discussion of PID
accuracy in P-1626 for further information on this decision.
(e) Condemnation Criteria for Repeat Tests
    CTC and Bancroft Hinchey submitted comments requesting we revise
the condemnation criteria for cylinders that are subjected to a
repeated test due to equipment malfunction or operator error to 5
percent permanent expansion, rather than 10 percent. CTC states that
increasing the pressure by 10 percent, or 100 psig for the repeat test,
is not enough to ensure that an unsafe cylinder exhibits a permanent
expansion over 10 percent. Bancroft Hinchey states that an increase of
10 percent/100psi can be insufficient to give measurable plastic
deformation and resultant permanent expansion >10 percent due to the
gradient of the load/extension curve immediately after yield point. An
increase of 100psi at a (minimum) test pressure of 3000 psi (the lowest
pressure above 3000) represents a pressure increase of only 3100/3000 =
3.3 percent and is unlikely to give a resultant 10 percent plastic
deformation.
    PHMSA response. We do not agree with CTC and Bancroft Hinchey's
comments to change the condemnation criteria for cylinders in this
case. CGA C-1 limits cylinder requalifiers to only two repeated tests
in the event of equipment malfunction or operator error, and we do not
believe that there is a safety justification to change the condemnation
criteria to permanent expansion that is 5 percent of total expansion in
cases where a repeat test is conducted. We acknowledge that repeated
tests may result in some stretching of the cylinder, resulting in
cylinders passing requalification that may have otherwise failed;
however, this risk is minimized by limiting requalifiers to a maximum
of two repeat tests in the event of equipment failure or operator
error. Further, this provision does not authorize the retest of a
cylinder otherwise required to be condemned by Sec.  180.205(i). The
final rule, therefore, does not change the condemnation criteria for
cylinders subjected to a repeat test.
(f) Letters of Interpretation
    In P-1515, CTC further requested that PHMSA rescind two letters of
interpretation (Reference Nos. 00-0309 and 05-0087) that discuss the
number of repeat tests allowed in the event of equipment malfunction
and required hold time for pressure tests, respectively. Bancroft
Hinchey supports retracting these letters of interpretation.
    PHMSA response. We agree that adopting CGA C-1 will eliminate the
confusion regarding the number of permitted repeat tests in case of
system failure or operator error, as well as the required pressure hold
time, that the letters of interpretation attempted to clarify. This
final rule supersedes the two letters of interpretation. Affected
entities should not rely on 00-0309 and 05-0087 because they are no
longer valid and will be removed from our website.
(2) Comments Related to Sec.  180.205
(a) Grinding and Sanding
    NPGA and Amerigas opposed the proposed changes in Sec.
180.205(d)(4) and (f)(5) regarding grinding and sanding of cylinders.
Bancroft Hinchey submitted a comment supporting the proposed changes in
Sec.  180.205(d)(4).
    PHMSA response. Our intent in Sec.  180.205(d)(4) and (f)(5) is to
address methods of cleaning or repair that remove wall thickness from
the cylinder. Cleaning methods, regardless of the tool used, that only
remove loose debris or paint from the cylinder while not removing wall
thickness are not considered ``grinding.'' In this final rule we modify
Sec.  180.205(d)(4) and (f)(5) to clarify our intent and to authorize
grinding or sanding performed by any authorized repair facility.
(b) Reordering of Condemnation Criteria
    CTC submitted a comment requesting that we swap Sec.
180.205(i)(1)(v) and (vi) in order to have the condemnation criteria
for DOT 4E cylinders immediately follow the general requirements in
Sec.  180.205(i)(1)(iv).
    PHMSA response. We do not agree with CTC's comment to re-order
Sec.  180.205(i)(1). Changing the citations for the condemnation
criteria section will result in increased confusion and we do not
believe it is in the best interest of safety.
(c) Additional Condemnation Criteria
    Bancroft-Hinchey commented that we should add one additional
criterion to Sec.  180.205(d), Conditions requiring tests and
inspections of cylinders, for cases where a cylinder is discovered with
incorrect markings.
    PHMSA response. We are not adopting the suggested change in
Bancroft-Hinchey's comment. They did not provide enough information to
make a judgement on the merits of the proposal. The public may make a
separate petition further explaining the issue.

(3) Comments Related to Sec.  180.207
(a) Deletion of Sec.  180.207(a) and (b)
    Certified Training Company (CTC) submitted a comment requesting
that we delete Sec.  180.207(a) and (b), because these instructions
could be combined with Sec.  180.205(c).
    PHMSA response. While we agree with CTC that these paragraphs serve
similar purposes, we do not agree with CTC's comment to delete Sec.
180.207(a) and (b) and consolidate them into Sec.  180.205(c). The
current structure of the HMR generally separates instructions for DOT
specification cylinders and UN ISO pressure receptacles because of
differences in their design and construction. These paragraphs in Sec.
180.207 are necessary to provide enforceable instructions for shippers
and fillers of UN pressure receptacles separately from shippers and
fillers of DOT specification cylinders.
(b) Ultrasonic Examination for High Tensile Strength UN Pressure
Receptacles
    CTC and Worthington submitted a comment requesting that we remove
language from Sec.  180.207(d) that requires ultrasonic examination
(UE) of certain UN pressure receptacles.
    PHMSA response. We do not agree with CTC and Worthington's comment
to remove the requirement that UN cylinders with a tensile strength
greater than or equal to 950 MPa must be requalified by UE in
accordance with ISO 6406 in Sec.  180.207(d)(1). This requirement
serves an important safety purpose. High strength steels exhibit a
reduction of fatigue stress endurance during requalification and are
therefore unsuitable for pressure testing. In general, the fatigue
stress endurance limits increase with increasing ultimate tensile
strength (the specifics are alloy dependent). At a certain ultimate
tensile strength level, the fatigue stress endurance limit is
drastically reduced with increasing tensile strength due to notch
sensitivity. Increased notch sensitivity is a result of finer
microstructural features that lead microstructural damage evolution
(dislocation slips eventually accumulating to micro void coalescence
and the initiation of a fatigue crack). Performing UE of high-strength
seamless steel during requalification will detect fatigue cracks in
cylinders/tubes while hydrostatic testing coupled with visual
inspection has a significantly lower probability of detecting any
fatigue cracks in cylinders/tubes. Therefore, we are continuing to
require UE for UN cylinders with a tensile strength greater than or
equal to 950 MPa.
(c) Acetylene Test Interval
    During review of the NPRM, we noted that the proposed revisions to
Sec.  180.207(d)(3) for dissolved acetylene UN cylinders were not in
alignment with the suggested test intervals in ISO 10462(E) or ISO
10462 2013(E). Therefore, in the final rule, we will not make the
proposed changes to Sec.  180.207(d)(3).
(4) Comments Related to Sec.  180.209
(a) Revisions to Requalification of Cylinders Table
    CTC and Independent Cylinder Training (ICT) submitted comments
requesting we replace ``DOT 3'' with ``ICC 3'' and CTC and Bancroft
Hinchey's comment to re-insert ``10'' for DOT 3A and 3AA and ``7'' for
4B, 4BA, 4BW cylinders in Sec.  180.209(a) Table 1.
    PHMSA response. We agree with CTC, ICT, and Bancroft Hinchey that
there are errors in the table in Sec.  180.209(a) Table 1. However, we
proposed changes to Sec.  180.209(a) Table 1 in a different rulemaking
\1\ and will take no action in this rulemaking to avoid potential for
complication and confusion.
---------------------------------------------------------------------------

    \1\ See Response to an Industry Petition to Reduce Regulatory
Burden for Cylinder Requalification Requirements, NPRM, 84 FR 38180
(Aug. 6, 2019).
---------------------------------------------------------------------------

(b) Foreign Cylinders
    CTC and Wesley Scott submitted comments requesting that we change
the requalification requirements for foreign cylinders in Sec.  180.209
Table 1.
    PHMSA response. We do not agree with CTC and Wesley Scott's
comments regarding test pressure of foreign cylinders in Sec.
180.209(a) Table 1. Foreign-marked ISO cylinders are subject to the
requirements of Sec.  180.207, and would not be subject to test at \5/
3\ of service pressure. Therefore, we will not change this requirement
in Table 1.
(c) Footnote 1
    CTC, ICT, Hydro-Test Products and COSTHA's comments noted that we
inadvertently deleted Footnote 1 of Table 1 in Sec.  180.209 and
requested that we reinsert the footnote.
    PHMSA response. It was not our intent to change the requirements
applicable to these small cylinders. In this final rule, we are not
making any of the proposed changes to the table in Sec.  180.209 to
avoid conflicts with other rulemaking efforts. In this final rule, we
are not removing Footnote 1 of Table 1 in Sec.  180.209.
(d) Special Filling Limits (``+'' Mark) Relocation
    In P-1515, CTC requested that we move the requirements for special
filling limits for DOT 3A, 3AX, 3AA, 3AAX and 3T cylinders found in
Sec.  173.302a(b) to Sec.  180.209. We did not propose to take this
action in the NPRM. CTC submitted a comment to the NPRM requesting that
we reconsider our decision not to propose the change.
    PHMSA response. We disagree with CTC's request to move the current
requirements in Sec.  173.302a(b) (``Special filling limits for DOT 3A,
3AX, 3AA, 3AAX and 3T cylinders'') to Sec.  180.209. The requirements
in Sec.  173.302a(b) deal with filling, and are properly placed in a
filling section rather than a requalification section. Moving the
requirements to a requalification section in part 180 would create
unnecessary confusion. We additionally disagree with CTC's request to
modify the language in Sec.  173.302a(b) to remove the table of steel
types, average wall stress limitation, and maximum wall stress
limitation. We acknowledge that this information can be found in CGA C-
5, which is incorporated by reference into the section, but we continue
to see value in reproducing the table in the HMR for accessibility
purposes. We did not propose this change in the NPRM, and we will not
adopt this change in the final rule.
(e) 10-Year Requalification Condition Revisions (``Star'' Mark)
    CTC submitted a comment regarding the applicability of the ``star''
marking for 10-year requalification in Sec.  180.209(b), specifically
requesting that we modify the change proposed in the NPRM to allow
cylinders used in vehicles to continue to take the exception.
    PHMSA response. PHMSA is not changing the applicability of the 10-
year requalification to prohibit cylinders used in clusters, banks,
groups, racks, or vehicles. If fillers are not removing these cylinders
from the cluster, bank, group, rack, or vehicle, as stated by CTC in P-
1515, then they may not use the exception unless they have been issued
a special permit. Changing the applicability of the exception is not an
appropriate way to deal with this supposed compliance problem. We
encourage cylinder users and fillers to re-familiarize themselves with
the conditions for the 10-year requalification for DOT 3A and 3AA
cylinders.

(f) 10-Year Requalification Expansion Limit
    ICT and Bancroft Hinchey also commented about their opposition to
another part of this proposed change to Sec.  180.209(b), namely the
new limit of 5 percent permanent expansion for these cylinders.
    PHMSA response. In this final rule, we are not modifying the
applicability of the exception or creating a new permanent expansion
limit. We are, however, modifying the exception by removing the
``hammer test,'' as requested in P-1515 and proposed in the NPRM. The
hammer test is outmoded and no longer provides relevant information
regarding the continued strength of the cylinder. We may consider
further modifying this exception in the future.
(5) Eddy Current Testing
    In the NPRM we proposed to change the applicability of the eddy
current test, eddy current condemnation criteria, and eddy current
record keeping requirements, as requested in P-1515. We do not believe
the change and possible increase in cost is justified by data at this
time. Therefore, in this final rule, we are not making any changes
related to eddy current testing applicability, condemnation criteria,
or recordkeeping.
(a) Test Applicability
    Currently, eddy current testing is required for 3AL cylinders made
of aluminum alloy 6351-T6 in SCUBA, SCBA, or oxygen service. 3AL 6351-
T6 cylinders have been shown to be susceptible to sustained load
cracking (SLC) in the neck and thread area of the cylinder. Eddy
current testing combined with a detailed visual examination can
identify SLC before it poses an immediate danger. We have required eddy
current testing since the publication of HM-220F (71 FR 51122; 8/29/
2006). P-1515 requested that we change the applicability of the eddy
current test to any DOT 3AL cylinder made of 6351-T6 alloy with a
service pressure at or above 1,800 psig. We received one comment in
support of this change from ICT. We did not discuss the proposed change
in detail in the preamble to the NPRM, only stating, ``Specifically we
plan to revise . . . the paragraph (m) requalification conditions for
DOT 3AL cylinders made of 6351-T6 aluminum alloy.'' We are concerned
that the change from a gas service-based testing applicability to a
pressure-based testing applicability may significantly increase the
number of cylinders subject to eddy current testing, without adequate
notice to the regulated community or safety justification.
    Since the imposition of the eddy current test requirement in 2006,
we are not aware of any catastrophic failures of DOT 3AL cylinders
involving sustained load cracking. In this final rule, we are not
making the proposed change to eddy current test applicability. We
welcome further petitions on the matter, but we do not believe the
change and possible increase in cost is justified by data at this time.
(b) Condemnation Criteria
    Similarly, we are not making any change to eddy current
condemnation criteria. The current criteria in the HMR have proved
successful in identifying cylinders prone to sustained load cracking,
facilitating their removal from service before cracks can cause
catastrophic failure. We may consider revising the condemnation
criteria in a future rulemaking, but will make no change to eddy
current condemnation criteria at this time.
(c) Record-Keeping
    In the NPRM, we proposed changes to eddy current recordkeeping
requirements. We proposed to move eddy current recordkeeping
requirements currently found in appendix C to part 180 to new Sec.
180.215(b)(5). We received a comment from ICT opposed to the relocation
of requirements from appendix C to part 180 into Sec.  180.215(b)(5).
We agree with ICT and are not making the proposed change to relocate
requirements out of appendix C to part 180 at this time. Eddy current
testers are familiar with the requirements found in appendix C to part
180 and moving the requirements to a new section would create
unnecessary confusion. We may review eddy current recordkeeping
requirements in a future rulemaking.
(6) Comments Related to Sec.  180.209(j)
(a) Incorporation by Reference of CGA C-1
    CTC commented on the proposed language in Sec.  180.209(j) and
stated their opinion that the language was unnecessarily confusing and
redundant following the incorporation of CGA C-1.
    PHMSA response. We agree with CTC's comment that there are
redundant instructions in Sec.  180.209(j), and the requirements could
be simplified by referring to the test procedures in CGA C-1.
Additionally, COSTHA noted an error in the structure of Sec.
180.209(j), where it appeared the proposed paragraphs (j)(2) and (3)
overlapped in applicability and contradicted each other. We appreciate
this comment, and have re-structured Sec.  180.209(j) to make clear
that paragraph (j)(1)(i) applies to smaller 4B, 4BA, 4B240ET, or 4BW
cylinders, paragraph (j)(1)(ii) to larger 4B, 4BA, 4B240ET, or 4BW
cylinders, and (j)(2) to 3A, 3AA, or 3AL cylinders.
(b) Increased Pressure for Repeat Tests
    ICT commented on our proposed requirement to increase the pressure
by 10 percent for a repeated proof pressure test for fire
extinguishers, noting this was not in accordance with CGA C-1
requirements.
    PHMSA response. We agree, and are removing this provision and
replacing it with instructions to conduct the proof pressure test in
accordance with CGA C-1.
(c) 4E Cylinders
    While reviewing Sec.  180.209(j), we noted erroneous references to
DOT 4E cylinder condemnation criteria. DOT 4E cylinders are generally
not eligible to be transported or requalified as fire extinguishers, so
we have removed the reference to 4E condemnation criteria from Sec.
180.209(j).
    In the final rule, we are revising Sec.  180.209(j) as discussed
above to simplify and clarify the requirements for the requalification
of specification fire extinguishers.
(7) Comments Related to Sec.  180.212
    Bancroft Hinchey commented in support of the proposed requirement
in Sec.  180.212(a)(3) to require ultrasonic testing (UT) after a
repair facility conducts a repair involving grinding.
    PHMSA response. In this final rule, we are adopting this
requirement as proposed.
(8) Comments Related to Sec.  180.213
(a) Requalification Label Embedded in Epoxy
    Numerous commenters, including NPGA, Amerigas, Firehouse Hydro
Sales and Service, Joshua Blake, Hydro-Test Products, and Scuba Do
noted that we made an error in Sec.  180.213(c) for requalification
marking methods by removing the authorization for a label embedded in
epoxy.
    PHMSA response. The commenters are correct that we inadvertently
did not include the provision allowing for applying a label embedded in
epoxy. This was not our intent as part of the HM-234 NPRM. Therefore,
in this final rule we are including the label in epoxy marking method
in Sec.  180.213(c) as is currently allowed under the HMR. We
appreciate the commenters' attentiveness in addressing this
unintentional omission in the NPRM.

(b) Requalification Marking Location
    Independent Cylinder Training (ICT), Amerigas, and NPGA oppose the
proposed requirement in Sec.  180.213(c)(1)(i) that would require
requalification marks be placed in a specific location adjacent to the
original manufacturing markings. ICT, Amerigas, and NPGA state that
this requirement is too restrictive, and in certain cases impossible to
meet due to the size and type of cylinders involved. Bancroft Hinchey
supports a requirement to ``lay out requalification markings neatly and
consistently.''
    PHMSA response. We agree with the comments submitted by ICT,
Amerigas, and NPGA. While we would have liked to provide a consistent
location for requalification markings for shippers and fillers, we
recognize the diversity of cylinder types and sizes makes this effort
difficult. Therefore, in this final rule we are not adopting the change
to Sec.  180.213(c) that was proposed in the NPRM. Requalification
markings must be applied in a legible and durable manner and may be
placed on any portion of the upper end of the cylinder excluding the
sidewall. We welcome petitions on this requirement for possible
inclusion in a future rulemaking.
(c) Requalification Marking Depth
    Bancroft Hinchey commented that Sec.  180.213(c) should be modified
to provide guidance on requalification marking depth when the cylinder
specification does not provide any information on accepting marking
depth.
    PHMSA response. While PHMSA agrees that cylinder requalifiers
should not mark cylinders to a depth greater than the original
manufacturer's markings, we do not agree with Bancroft Hinchey's
comment to modify Sec.  180.213(c). PHMSA believes that including the
phrase ``or the original manufacturer's markings'' to Sec.  180.213(c)
will increase confusion among cylinder requalifiers.
(9) Comments Related to Sec.  180.215
(a) Use of Symbols for Cylinder Dimension
    Bancroft Hinchey requested clarification of the revision to Sec.
180.215 to permit use of symbols for actual dimensions.
    PHMSA response. The use of a symbol in place of the written
dimensions of the cylinder is permitted by Sec.  180.215(b) as long as
the symbols on the reference chart available at the requalifier's
facility are accurate for the actual measured dimensions of each
cylinder requalified. It is PHMSA's understanding that some cylinder
requalifiers maintain reference charts with symbols cross-referenced to
the actual measured dimensions of common cylinder models. As long as
the facility has an accurate reference document that cross-references
the symbol entered on the requalification record with the actual
measured dimensions of the cylinder requalified, they may use that
symbol to meet the requirement to enter the actual dimensions of a
cylinder on the requalification record. This will increase flexibility
and reduce burdens for requalifiers without compromising safety.
(b) Gas Service and Year of Manufacture
    Hydro-Test Products commented on the proposed change to cylinder
requalification recordkeeping requirements. They noted that in the NPRM
we did not discuss the additional requirement to record the cylinder's
year of manufacture or gas service in Sec.  180.215(b)(2). Hydro-Test
Products is opposed to the proposed change to cylinder requalification
recordkeeping requirements and believes it would impose an undue burden
on cylinder requalifiers.
    PHMSA response. We disagree with Hydro-Test Products' comment. The
requirement for cylinder requalifiers to keep a record of the
cylinder's date of manufacture and gas service is useful for several
reasons. The eligibility for the ``star'' mark in Sec.  180.209(b),
allowing a 10-year requalification period instead of 5 years, depends
on the year of manufacture and gas service, as does the ``+'' mark for
10 percent overfilling in Sec.  173.302a(b). The applicability of the
option to requalify a cylinder via external visual inspection in Sec.
180.209(g) is also dependent on the particular gas service in which the
cylinder is used. The year of manufacture is also helpful in
determining whether a 3AL cylinder was constructed from 6351-T6
aluminum alloy, and therefore subject to eddy current examination. Use
of 6351-T6 aluminum alloy in DOT 3AL cylinders was discontinued in
1990. We believe that the addition of these two pieces of information
to cylinder requalification records creates only a minimal reporting
burden on the regulated community while aligning recordkeeping
requirements with operational practice. See further discussion in
Section VIII.G in this rulemaking document regarding the information
collection burden of this requirement. In this final rule, we are
adopting the changes as proposed, and modifying Sec.  180.215(b)(2) to
require cylinder requalifiers to record the year of manufacture and gas
service of each cylinder they requalify.
(10) Reclaimed Refrigerant Gas
    Section 180.209(e) authorizes proof pressure testing for DOT 4-
series cylinders in non-corrosive gas service. In the NPRM we proposed
to add the following sentences to this paragraph: ``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.'' In this final rule, we are not adding these
sentences to Sec.  180.209(e). Although we believe that cylinders used
for reclaimed refrigerant gases are generally not eligible for the
exception in Sec.  180.209(e) because of the contaminants encountered
in this service, we are uncertain whether this is always the case.
Therefore, PHMSA has decided that the most practical regulatory
alternative at this time is to leave the Sec.  180.209(e) exception
allowing a 10-year testing interval for DOT 4-series cylinders used in
non-corrosive gas service unchanged. As provided in Sec.  173.22, it is
the shipper's responsibility to classify a hazardous material properly.
(11) RIN Markings for Foreign Cylinders
    In the HMR, foreign cylinders not manufactured to a DOT, UN, TC,
CTC, BTC or CRC specification may be filled and transported for export
or for use on board a vessel in accordance with Sec.  171.23(a)(5)
(note that this reference was originally Sec.  171.23(a)(4), and has
changed to Sec.  171.23(a)(5) after publication of final rule HM-219C).
Requalification for these cylinders is discussed in Sec.  180.209(l),
which prohibits the marking of the cylinder with a requalifier's RIN,
instead requiring only the month and year of requalification. In the
NPRM, we proposed to require a RIN marking for these foreign cylinders,
along with the symbol ``EX,'' to reduce confusion among fillers and
clarify that these foreign cylinders had been requalified in accordance
with part 180, subpart C. We received no comments on this proposal. In
this final rule, we will adopt this requirement. We believe that the
symbol ``EX'' in association with the RIN provides necessary
information to inspectors and users that these cylinders are limited to
export or vessel service in accordance with Sec.  171.23(a)(5). The
inclusion of a RIN marking, which signifies compliance with part 180
subpart C, will increase clarity for fillers

that the cylinders have been properly requalified.

P-1521

    CGA submitted P-1521 requesting that PHMSA modify a provision in
Sec.  172.400a(a)(1) (specifically Sec.  172.400a(a)(1)(i) at the time
the petition was submitted) 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. In the NPRM, PHMSA
proposed to revise Sec.  172.400a(a)(1)(i) to remove the limitation
that would only allow the use of the neckring markings if the cylinders
are not overpacked, as proposed in P-1521. National Association of Fire
Equipment Distributors (NAFED) and Worthington Cylinder submitted
comments supporting this change.
    On January 21, 2016, PHMSA published HM-233F (81 FR 3635), which
adopted numerous special permits into the HMR. In particular, we
adopted DOT SP 14251, which authorizes the transportation of overpacked
cylinders marked in accordance with CGA publication C-7 provided the
overpacks are properly labeled. Therefore, the intent of P-1521 has
already been accomplished. We appreciate CGA's petition and COSTHA's
comment highlighting that HM-233F already addressed this issue.

P-1538

    On behalf of Jetboil, Inc., The Wicks Group submitted P-1538
requesting that PHMSA revise Sec.  173.306(a)(1) to permit camping
stove cylinders containing liquefied petroleum gas (LPG) in amounts
less than 4 ounces but in a container exceeding 4 fluid ounce capacity
to be shipped as consumer commodity (ORM-D). Historically, PHMSA has
limited the amount of compressed gas in limited quantity packagings to
reduce the opportunity and speed of the gaseous product's reaction to
an activating event, having found that including non-gaseous materials
in the same container with the gas--such as foodstuffs, soap, etc.--
slowed this reaction. The Interstate Commerce Commission first adopted
the provision for Sec.  173.306(a)(1) (previously Sec.  73.306(a)(1))
in a final rule published July 1, 1966 (31 FR 9067). The provision
provided an ``exemption'' (i.e., an exception) from regulations for
shipping of compressed gases ``when in containers of not more than 4
fluid ounce water capacity.'' Thus, historically, the provision applies
to the capacity of the container and not to the quantity of its
contents. This is consistent with design requirements for the capacity
of packagings found in part 178 that includes a specification for the
water capacity of the packaging (e.g., Specification 3A and 3AX
seamless steel cylinders in Sec.  178.36); however, the publication of
a final rule on April 15, 1976 (41 FR 15972) inadvertently dropped the
term ``water'' from paragraph (a)(1) regardless of there having been no
express discussion of the intent to do so or to change the size
standard from the originally adopted water capacity to the quantity of
the contents.
    Furthermore, the definition ``maximum capacity'' was introduced as
part of a harmonization effort with international regulations and
standards in a final rule published December 21, 1990 (55 FR 52402) for
consistency with use of terminology internationally for UN performance
oriented packaging. See the part 178, subpart L non-bulk performance
oriented packaging sections. Therefore, based on the historical context
of capacity as its use in Sec.  173.306(a)(1) to mean water capacity
and the adoption of the term ``maximum capacity'' in association with
the adoption of UN performance oriented packaging, PHMSA did not
propose to adopt the petition. We received one comment on this topic.
Worthington Cylinder submitted a comment supporting PHMSA's proposal to
deny the petition and not amend Sec.  173.306(a)(1). Therefore, as
reasoned in the NPRM, we are not adopting P-1538 in this final rule.

P-1539

    Matheson-TriGas submitted P-1539 requesting that PHMSA revise Sec.
180.209, which prescribes requirements for requalifying cylinders.
Paragraph (a) of Sec.  180.209 requires each DOT-specification cylinder
listed in ``table 1 of this paragraph'' to be requalified and marked in
conformance with requirements specified in Sec.  180.209. The
petitioner requested that PHMSA extend the 10-year retest period
prescribed in this table for DOT 3A, 3AA, and 3AL specification
cylinders in Division 2.2 (non-flammable) gas service to once every 15
years. Matheson-TriGas also requested in its petition that PHMSA extend
the 5-year retest period prescribed in this table for DOT 3A, 3AA, and
3AL specification cylinders in Division 2.1 (flammable) gas service to
once every 10 years. The petitioner states: ``Historically over 99.4
percent of cylinders in the above[-mentioned] services that were
[subjected] to the water jacket test pass the test,'' and ``it is more
likely . . . the cylinder failed the external or internal visual [test]
rather than failing the water jacket test.''
    Matheson-TriGas notes PHMSA's statement from an earlier rulemaking
(HM-220; 63 FR 58460) regarding the history of the plus rating for
steel cylinders resulting from the steel shortage of World War II,
which resulted in changes ``that benefitted the industry with no
compromise of public safety down to this day.'' Matheson-TriGas
extrapolates that we face similar metal shortage challenges in today's
economy.
    Based on concerns about increasing the risk of cylinder failure by
lengthening the timeframe between periodic qualifications, PHMSA did
not propose to revise the 10-year requalification period for DOT 3A,
3AA, and 3AL specification cylinders in Division 2.2 (non-flammable)
gas service to once every 15 years, nor to revise the 5-year
requalification period for DOT 3A, 3AA, and 3AL specification cylinders
in Division 2.1 (flammable) gas service to once every 10 years.
    We received three comments on this topic. Bancroft Hinchey, NAFED,
and CGA all supported our decision not to adopt the petition.
Therefore, as reasoned in the NPRM, we are not adopting P-1539.

P-1540

    CGA submitted P-1540 requesting that PHMSA require newly
manufactured DOT 4B, 4BA, 4BW, and 4E cylinders to be marked with the
mass weight or tare weight, and the water capacity. As specified in
Sec.  178.35(f), the HMR require DOT-specification cylinders to be
permanently marked with specific information, including the DOT-
specification, the service pressure, a serial number, an inspector's
mark, and the date manufacturing tests were completed. These marks
provide vital information to fillers and uniquely identify the
cylinder.
    Certain DOT 4-series specification cylinders contain liquefied
gases filled by weight, so the tare weight (the weight of the empty
cylinder and appurtenances) or the mass weight (the weight of the empty
cylinder), and the water capacity must be known by the filler to fill
the cylinder properly. This information is essential for cylinders
filled by weight, as cylinders overfilled with a liquefied gas can
become liquid full as the ambient temperature increases. If
temperatures continue to rise, pressure in the overfilled cylinder will
rise disproportionately, potentially leading to leakage or a violent
rupture of the cylinder after only a small rise in temperature. Despite
these risks, the HMR do not require tare weight, mass

weight, or water capacity markings on DOT-specification cylinders.
    To address this, the CGA petitioned PHMSA to require tare weight or
mass weight, and water capacity to be marked on newly constructed DOT
4B, 4BA, 4BW, and 4E specification cylinders. The petition also
requests that PHMSA provide guidance on the accuracy of these markings
and define the party responsible for applying them. In its petition,
CGA notes that PHMSA has incorporated by reference the National Fire
Protection Association's ``58-Liquefied Petroleum Gas Code, 2001
edition'' (NFPA 58), which requires cylinders used for liquefied
petroleum gases to be marked with the tare weight and water capacity;
\2\ however, as stated in the petition, NFPA 58 gives no guidance as to
the accuracy of these markings or the party required to provide them.
The CGA states that this lack of guidance can lead to the overfilling
of a cylinder and the potential for unsafe conditions.
---------------------------------------------------------------------------

    \2\ Note that NFPA 58 was not incorporated by reference for
marking purposes but for purposes of equipping storage tanks
containing LPG or propane with safety devices. See Sec.  173.315(j).
---------------------------------------------------------------------------

    While DOT 4B, 4BA, 4BW, and 4E cylinders are often used to
transport liquefied compressed gas, we noted in the ANPRM that these
are not the only cylinder types used for liquefied compressed gas
transport. PHMSA understands that many in the compressed gas industry,
especially the liquefied petroleum gas industry, already request
manufacturers to mark cylinders with the tare weight or water capacity
as an added safety measure. Based on this assumption, PHMSA estimates
the impact on the liquefied compressed gas industry will be minimal, as
many in the industry are already applying these markings voluntarily.
    PHMSA requested comments and supporting data regarding the
increased safety benefits and the economic impact of this proposal.
With regards to the cost associated with this modification, in the
ANPRM, PHMSA asked the following specific questions:
     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 submitted a comment to the ANPRM that
supported the petition but they did not discuss the basis for their
support. CGA submitted a comment to the ANPRM supporting 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 did 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 believed that the HMR must further clarify that no
cylinder may 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, to 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
to 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 DOT 3-series cylinders
where the additional marking would not fit onto the dome of the
cylinder.
     The economic impact estimated for marking all cylinders is
significantly greater than the estimates submitted by PHMSA.

Manchester Tank submitted a comment to the ANPRM expressing concern
that numerous variations in stamped weights could cause confusion in
the field among fillers. They stated 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 asked PHMSA to
clarify who would have responsibility to assign the duty to mark tare
weight to the valve installer and indicated that there are many
cylinders that are not valved by the manufacturer, and 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 the NPRM, PHMSA proposed to revise Sec.  178.35(f) to require
that tare weight or mass weight, and water capacity be marked on all
DOT 4B, 4BA, 4BW, and 4E specification cylinders.
    We received nine comments to the NPRM related to this issue. Fike
Corporation, Janus Fire Systems, Amerex, NAFED, and FSSA submitted
comments opposing the requirement to mark all DOT 4B, 4BA, 4BW, and 4E
cylinders with tare weight or mass weight, and water capacity. Bancroft
Hinchey, Kidde-Fenwal, Worthington Cylinder and CGA submitted comments
generally supportive of the requirement, but requested certain
modifications. Bancroft Hinchey requested that Sec.  180.215 be
modified to require tare weight be added to a 4-series cylinder if it
changes service to liquefied gas. Kidde-Fenwal requested that the
marking requirements only apply to cylinders filled with liquefied gas,
and not 4-series cylinders used for other services, such as fire
extinguishers containing an extinguishing agent and charged with a non-
liquefied gas. Worthington Cylinder requested that the requirement only
apply to cylinders filled with liquefied gas and that the regulations
require specific acronyms for mass weight, tare weight, and water
capacity to reduce confusion. CGA requested a minor change to the
wording in Sec.  178.35(f)(7)(iii) to ensure proper tolerance
requirements as requested in P-1540.
    PHMSA response. We agree with the commenters that there is no value
in requiring the tare weight or mass weight, and water capacity
markings for 4-series cylinders that are not used for liquefied
compressed gases, as these materials are not filled by weight. However,
we do not agree that relying on voluntary industry standards that may
require the tare weight or water capacity on a cylinder label is
adequate to alleviate our safety concerns regarding proper filling of
liquefied compressed gases. We do not believe that NFPA 58 is
universally followed in the cylinder industry. Additionally, the NFPA
58 does not assign a particular

party to apply the marks, or any accuracy requirements for the
measurements. Therefore, the creation of a Federal standard for tare
weight/mass weight and water capacity markings on DOT 4B, 4BA, 4BW and
4E cylinders used for only liquefied compressed gases provides a higher
level of safety and oversight than the NFPA 58 standard while limiting
burdens to the cylinder industry.
    PHMSA expects this marking requirement to play a role in preventing
overfilling incidents, which can result in explosions and fatalities.
For example, in 2014, an overfilled propane cylinder ruptured,
exploded, and fatally injured two people and injured others in
Philadelphia.\3\ Specifically, a cylinder filler, using the tare/mass
weight and water capacity markings to guide their filling practice, is
expected to be significantly less likely to overfill a cylinder. Adding
tare weight or mass weight, and water capacity markings is expected to
improve safety for cylinder fillers, transporters, and the general
public by decreasing the incidence of overfilled cylinders entering
transportation. Cylinders filled with liquefied gases must be filled by
weight (see Sec.  173.304a(c)). The filler must determine the weight of
the cylinder in order to fill the cylinder with the proper amount of
liquefied gas. The most direct way to ensure that the filler knows the
weight of the cylinder being filled is to require that the cylinder's
weight be marked on the cylinder itself.
---------------------------------------------------------------------------

    \3\ This incident resulted in a Federal judge ordering the
company who filled the cylinder to pay a $1 million criminal. In
addition, the company entered into an historic civil settlement,
agreeing to pay victims and the family of those fatally injured $160
million, plus an additional confidential sum. See Moselle, Aaron. U-
Haul fined $1 million after fatal food truck explosion in North
Philly. May 7, 2019. WHHY.org. Available at: https://whyy.org/articles/uhaul-fined-1-million-after-fatal-food-truck-explosion-in-north-philly/.
---------------------------------------------------------------------------

    By requiring these markings, PHMSA will help to eliminate confusion
and guesswork while providing a potentially quicker and more efficient
way to determine the cylinder weight than relying solely on reference
materials listing cylinder weights. Cylinder fillers may not always
have easy access to cylinder tare/mass weight and water capacity
reference materials; the materials may become outdated; or the
reference materials that are available may have been created by a
cylinder manufacturer other than the manufacturer of the cylinder being
filled.
    In addition, providing the markings may prevent a cylinder filler
from being required to weigh the purportedly empty cylinder to
determine the tare weight, removing errors due to residue material that
would overstate the tare weight when weighed manually, and also
reducing burden. Further, PHMSA believes that the addition of these
markings could reduce the occurrence of non-compliant filling methods,
such as informally relying on auditory cues (e.g., shaking the
cylinder).
    Increasing availability of cylinder weight and capacity information
on the cylinder itself will decrease the chances of operator error
leading to overfilled cylinders. Therefore, in this final rule, we are
modifying the proposed requirement from the NPRM that DOT 4B, 4BA, 4BW
and 4E cylinders used for only liquefied compressed gases must be
marked with tare weight or mass weight, and water capacity. The details
are discussed in the VII. Section-by-Section Review. We are also
adopting the upper and lower tolerances for the tare weight/mass weight
marking as proposed by CGA. We agree that additional markings on a
cylinder may be a source of confusion, but we believe that this can be
mitigated by using standardizing abbreviations. Accordingly, in this
final rule we are requiring that tare weight be abbreviated ``TW'',
mass weight ``MW'', and water capacity ``WC.'' The responsibility for
meeting this requirement is placed on the owner of the cylinder, as
they are best positioned to understand the eventual use of the cylinder
at the time of manufacture. 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.
    In accordance with Sec.  173.304a(c), liquefied gases must be
filled by weight, or when the gas is lower in pressure than required
for liquefaction, a pressure-temperature chart for the specific gas may
be used to ensure that the service pressure at 55 [deg]C (131 [deg]F)
will not exceed \5/4\ of the service pressure at 21 [deg]C (70 [deg]F).
An accurate scale must be used to check the weight of liquefied gas
filled in the cylinder. These requirements apply to all types of
cylinders, not only the 4B, 4BA, 4BW and 4E cylinders whose marking
requirements we are amending in this final rule. We believe that by
requiring TW, MW and WC markings for these cylinders which are most
commonly used for liquefied gases, we will create the greatest safety
benefit while minimizing costs to the regulated community.
    We note that COSTHA submitted a comment that we left the word
``no'' out of the phrase ``[no] upper [tolerance]'' in the proposed
Sec.  178.35(f)(7)(iii) for the criteria for the water capacity marking
for a cylinder exceeding 25 pounds. COSTHA is correct in its
understanding. This was an inadvertent omission and we are correcting
Sec.  178.35(f)(8)(iii) (please note that the original regulatory text
proposed in Sec.  178.35(f)(7) has been redesignated as paragraph
(f)(8) due to changes made to the HMR since the publication of the HM-
234 NPRM) such that it reads ``with a tolerance of minus 0.5 percent
and no upper tolerance'' in this final rule.
    Lastly, we are making an editorial change in the final rule and
deleting the metric units from Sec.  178.35(f)(8) to increase clarity
and decrease confusion for manufacturers, fillers, and users of these
cylinders.

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.\4\
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).
---------------------------------------------------------------------------

    \4\ 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.
---------------------------------------------------------------------------

    PHMSA has written several letters of interpretation regarding the
applicability of Sec.  173.309 to fire extinguishers. Notably on March
9, 2005, PHMSA wrote a letter of interpretation (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 of interpretation (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 because these cylinders were not equipped to function
as fire extinguishers. This latter clarification effectively required
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 suggested 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 the NPRM, PHMSA proposed to revise the Sec.  173.309
introductory text to include ``fire extinguishers for installation as
part of a fire suppression system'' as a fire extinguisher type
authorized for transport in accordance with authorized packaging
requirements as assigned to the HMT entry for fire extinguishers.
    Comments. Guardian Services, Inc., Janus Fire Systems, Amerex,
Worthington Cylinder and the Fire Suppression Systems Association
commented in support of this proposal. Kidde-Fenwal commented in
support of the proposal, but also stated that ``not all cylinders
intended for use as a component of a fire suppression system should
utilize the `Fire extinguisher, UN 1044 designation' as suppression
agents with their own HMT designation (example, UN 3296) should
continue to be identified as such.'' That is, those fire suppression
agents listed by name should continue to be described and packaged as
provided in the HMT rather that as UN1044, Fire extinguishers.
    The National Association of Fire Equipment Distributors (NAFED)
commented in opposition to the proposal, specifically noting its
concerns with allowing high pressure, inert gas cylinders used in
``engineered-type'' fire suppression systems to be transported and
requalified as ``UN1044, Fire extinguishers.'' The ``engineered-type''
fire suppression systems that NAFED described are large fire
suppression systems used in industrial settings that may consist of a
vessel that contains an extinguishing agent and separate compressed gas
``charging'' cylinders that provide the pressure to inject the agent
into the system upon activation. Other engineered systems may consist
of a fire extinguishing agent pressurized with an inert gas, or consist
of cylinders that contain only an inert gas.
    PHMSA response. We disagree with Kidde-Fenwal. The classification
of ``UN1044, Fire extinguisher'' is based on the intended use of the
cylinder, and should not necessarily exclude gases listed by name in
the Sec.  172.101 HMT if the conditions of Sec.  173.309 are met.
However, we agree with NAFED's concerns regarding ``charging''
cylinders transported separately from fire suppression systems. Our
intent in the NPRM was to propose allowing fire extinguishers that are
charged with a compressed gas and an extinguishing agent and that are
intended for installation into fire suppression systems to be described
as ``UN1044, Fire extinguishers.'' We did not intend to allow cylinders
charged with an inert gas and used only to pressurize a fire
suppression system to be described as ``UN1044, Fire extinguishers''
when offered for transportation separately from the suppression system.
These ``charging'' cylinders must be described based on the compressed
gas they contain, for example ``UN1066, Nitrogen.'' or ``UN1006,
Argon.''
    In this final rule, we are adopting the proposed change to Sec.
173.309, and further clarifying our meaning. A fire extinguisher
charged with a compressed gas and an extinguishing agent that is
intended for installation into a fire suppression system may be
described as ``UN1044, Fire extinguisher'' if it meets the conditions
of Sec.  173.309. A fire extinguisher charged with a compressed gas
that is the sole extinguishing agent in the system that is intended for
installation into a fire suppression system may also be described as
``UN1044, Fire extinguisher'' if it meets the conditions of Sec.
173.309. A cylinder charged with a gas and used only to pressurize or
expel an extinguishing agent as part of a fire suppression system may
not be described as ``UN1044, Fire extinguisher'' for purposes of the
HMR.
    Section 173.309(a) requires the use of a DOT-specification
cylinder, as is generally required for a compressed gas, and further
requires the use of dry gas and extinguishing agents that are
commercially free from corroding components. The safety and performance
of DOT specification cylinders filled with dry gas and an extinguishing
agent commercially free of corroding components and requalified as
provided in Sec.  180.209(j) is expected to be the same for manual use
(i.e., handheld) and for use in fixed fire suppression system service.
Section 173.309(b) requires the use of Specification 2P or 2Q non-
refillable inside metal containers, filled with a non-corrosive
extinguishing agent. DOT 2P and 2Q containers are very limited in size
and service pressure by their design specification in Sec. Sec.  178.33
and 178.33a, and therefore would have limited utility for a fixed fire
suppression system. Finally, with respect to authorizing use of non-DOT
specification cylinders, we believe the requirements in Sec.
173.309(c) provide for the safe transportation of compressed or
liquefied gas regardless of whether the cylinder is equipped for manual
use as a fire extinguisher (i.e., handheld) or for use as a fire-
extinguishing component of a fire suppression system.
    Section 173.309(c) allows the use of non-specification cylinders
filled with a non-corrosive extinguishing agent as fire extinguishers.
These non-specification cylinders are limited in size to 1,100 cubic
inches, or 55 cubic inches if they contain any liquefied compressed
gas. The cylinders must be pressure tested to three times (3x) their
charged pressure prior to initial shipment, and must be designed with a
burst pressure six times (6x) their charged pressure. This exceeds the
burst pressure ratio of DOT-specification cylinders authorized under
Sec.  173.309(a). These non-DOT specification cylinders must
additionally be periodically requalified in accordance with the
requirements of the Department of Labor's Occupational Safety and
Health Administration regulations pertaining to ``portable fire
extinguishers'', 29 CFR 1910.157. The combination of size restriction,
higher than normal initial test pressure requirements, and much higher
than normal burst pressure capability creates an equivalent level of
safety for these non-DOT specification fire extinguishers when compared
to DOT

specification cylinders. We expect the same level of safety will be
achieved in handheld and fire suppression system service.
    Note that the changes made in this final rule do not affect the
description and classification of large fire extinguishers (see HM-
215M, 80 FR 1075, 1/8/2015 for background), which may contain
``charging'' cylinders when transported as a completed fire
extinguishing system provided they meet the conditions of Sec.
173.309.

P-1560

    Air Products and Chemicals Inc. (Air Products) submitted a petition
for rulemaking (P-1560) requesting that PHMSA revise Sec.
173.304a(a)(2) to adopt the provisions of SP 13599. SP 13599 authorizes
additional maximum filling densities for carbon dioxide and nitrous
oxide to include 70.3 percent, 73.2 percent, and 74.5 percent
respectively in DOT 3A, 3AA, 3AX, 3AAX, 3AL, and 3T cylinders with
marked service pressures of 2000, 2265, and 2400 psig, subject to
operational controls. In the NPRM, we did not propose to adopt this
provision because it was already adopted in the HMR by HM-233F (81 FR
3635).
    We received two comments related to P-1560 in this docket.
Worthington Cylinder agreed with our determination in the NPRM that we
had already adopted these provisions and therefore do not need to
address them again. Independent Cylinder Training (ICT) submitted a
comment proposing additional changes to Sec.  173.304a(a)(2). ICT
requested that cylinders with a service pressure of 2015 psig be
authorized for 70.3% fill density, like those with a service pressure
of 2000 psig. Additionally, ICT requested that PHMSA add a provision to
require that cylinders filled according to fill density be marked with
the water weight of the cylinder to aid in the filling process.
    PHMSA response. ICT's understanding of filling density requirements
for carbon dioxide is not correct. In the scenario it presents, a
cylinder with a service pressure of 2015 psig is already authorized for
a filling density of 70.3 percent for carbon dioxide. ICT's other
proposal regarding marking of water weight on a cylinder is beyond the
scope of this rulemaking and we suggest that ICT submit a separate
petition for rulemaking on the issue. As previously stated, P-1560
provisions were adopted into the HMR by rulemaking HM-233F, and
therefore we are not addressing it in this final rule.

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 the NPRM, we recognized 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 proposed 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 agreed 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 did not propose
to include 2P and 2Q in the allowance for the ``OVERPACK'' marking. We
proposed additional instructional language that the combination package
is not to be considered an ``overpack.''
    We received two comments on this issue. Alaska Air stated their
opposition to the proposed changes. Alaska Air states that the proposed
change is at variance with the existing Sec.  171.8 definition of
combination package, which will result in additional confusion by the
hazmat community, and that most shipments marked as proposed will be
rejected by air carriers because the ``overpack'' mark will be placed
on outer packages that are not overpacks.
    COSTHA also submitted comments regarding this issue. COSTHA
``supports this [revision] in principle and agrees with PHMSA and the
petitioner, 3M, that the differing marking requirements in Sec.  173.25
and Sec.  173.301(a)(9) to communicate similar conditions may be
causing confusion without enhancing safety.'' However, COSTHA also
notes that the sentence, ``[d]isplay of the `Overpack' marking is not
an indication that this combination package is an overpack'' is
confusing, and recommends that it be deleted.
    PHMSA response. PHMSA agrees with Alaska Airlines and COSTHA that
the proposed change could result in more confusion than it would
resolve and would not promote compliance with the HMR. Upon further
consideration, we do not believe a regulatory change is warranted. The
marking requirement in Sec.  173.301(a)(9) applies to a completed
package. The requirements in Sec.  173.25 apply to an enclosure used to
protect or consolidate completed packages. The ``OVERPACK'' applies to
the enclosure when specification packages are required and are not
visible. We do not view this as overly confusing. Therefore, in this
final rule we are not adopting any changes proposed in the NPRM based
on P-1563.

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).\5\ The
definition of MEGC in Sec.  171.8 states DOT-specification cylinders
are not authorized as part of MEGCs and accordingly, we are not
including the petitioned language referring to DOT-specification
cylinders in Sec.  173.312. DOT-specification cylinders filled with
liquefied compressed gas must be filled in accordance with the
instructions found in Sec.  173.304 and Sec.  173.304a, including
filling density limitations.
---------------------------------------------------------------------------

    \5\ Note that the petition specifically referenced the 17th
edition 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 the
NPRM, we proposed to specify the filling ratio requirements for
pressure receptacles.
    We received comments supporting this proposal from CGA and
Worthington Cylinder, and comments requesting modification to the
proposed language from FIBA Technologies (FIBA).
(1) Manifolding While Filling
    We received a comment from FIBA stating their opposition to the
sentence ``Manifolding while filling is not authorized.'' FIBA states
there would be no safety benefit to removing the manifold for many
MEGCs during filling because the MEGCs can be filled safely with the
manifold in place.
    PHMSA response. We agree with FIBA's comment. It was not our intent
to require the disconnection of the manifold during filling. Rather,
our intent is to require that each pressure receptacle is filled
individually when loading liquefied compressed gases. We acknowledge
that the manifold may remain in place as long as there are measures in
place to prevent more than one cylinder from being filled at a time
when loading liquefied compressed gas. Therefore, in the final rule we
will remove the sentence ``[m]anifolding during filling is not
authorized.''
(2) Filling With Non-Liquefied Gases
    FIBA also noted that our proposed revision accidently removed the
language currently in Sec.  173.312(b)(1) relevant to the filling of
MEGCs with ``permanent'' or non-liquefied gas.
    PHMSA response. This was not our intent; therefore, in the final
rule we will move the current language for permanent gases in Sec.
173.312(b)(1) to new Sec.  173.312(b)(1)(i) and insert the language
appropriate for filling with liquefied compressed gases in the new
Sec.  173.312(b)(1)(ii). Additionally, we agree with FIBA's suggestion
that there is value in specifying that Sec.  173.312(b)(1)(i) applies
to filling MEGCs with permanent, non-liquefied compressed gases, which
are filled by pressure, while Sec.  173.312(b)(2)(ii) applies to
liquefied gases, which are filled by weight.
    In this final rule, we are adopting P-1572, with the modifications
noted above. PHMSA emphasizes that this change does not impose a new
burden, as adoption of this proposal only emphasizes an important
safety requirement already stated in Sec.  173.304b for UN pressure
receptacles.

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 align with CGA S-1.1 for DOT 39 cylinders
filled with an oxidizing gas and offered for transportation by air.
Specifically, as prescribed in 4.2.2 of CGA S-1.1, the required burst
pressure of the rupture disc ``shall not exceed 80 percent of the
minimum cylinder burst pressure and shall not be less than 105 percent
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,