oxidizing, n.o.s.; or nitrogen trifluoride, must be 100 percent of the
cylinder minimum test pressure with a tolerance of `plus zero' to minus
10 percent.
    In response to PHMSA's NPRM entitled ``Hazardous Materials:
Miscellaneous Amendments'' published on September 29, 2010 (75 FR
60017) under Docket No. PHMSA-2009-0151 (HM-218F), HMT Associates
submitted a late-filed comment that identified a potential discrepancy
between the HMR and CGA S-1.1. Specifically, this commenter stated the
HMR have different PRD settings than CGA S-1.1 for DOT 39 cylinders
that make it virtually impossible to comply with both the HMR and CGA
S-1.1. Sections 173.302(f)(2) and 173.304(f)(2) require the rated burst
pressure of a rupture disc for DOT 3A, 3AA, 3AL, 3E, and DOT 39
cylinders to be 100 percent of the cylinder minimum test pressure with
a tolerance of `plus zero' to minus 10 percent, whereas section 4.2.2
of CGA S-1.1 requires the rated burst pressure of the rupture disc on
DOT 39 cylinders to be not less than 105 percent of the cylinder test
pressure.
    In the NPRM, PHMSA proposed to revise Sec.  173.301(f) as it
applies to DOT 39 cylinders to alleviate any confusion and conflict
between the PRD requirements in Sec.  173.301(f) and those in
Sec. Sec.  173.302(f)(2) and 173.304(f)(2) with respect to minimum
burst pressure of pressure relief devices on a DOT 39 cylinder used for
the transport of compressed and liquefied oxidizing gases by air.
    We received comments from HMT Associates and Worthington Cylinder
regarding P-1580. Both comments correctly noted that in the NPRM we
failed to amend the regulatory text in Sec. Sec.  173.302 and 173.304
as we stated in our NPRM discussion.
    PHMSA response. We agree with HMT Associates' comment noting that
the proposed language in Sec.  173.301(f)(4)(iv) is not strictly
necessary, because by revising Sec. Sec.  173.302(f)(2) and
173.304(f)(2) we will have brought the HMR into alignment with CGA S-
1.1 requirements. However, we will maintain the reference to the new
requirements in Sec.  173.301(f)(4)(iv) to increase the visibility of
the new requirements. We did not receive any comments opposed to the
proposed change. Therefore, in the final rule, we are amending
Sec. Sec.  173.302 and 173.304 to align with CGA S-1.1 requirements for
DOT 39 cylinders for oxidizing gases transported by air. To avoid
placing cylinders in conformance with the current requirements of
Sec. Sec.  173.302(f)(2) and 173.304(f)(2) out of service, we will
allow cylinders filled prior to the effective date of this rulemaking
that meet the current requirements of the HMR to remain in service
until the end of their useful lives.

P-1582

    Water Systems Council submitted P-1582 requesting that PHMSA revise
Sec.  173.306(g), which provides a limited quantity exception for water
pump system tanks, by permitting tanks manufactured to American
National Standards Institute (ANSI)/Water Systems Council (WSC)
standard PST 2000-2005 (2009) to be authorized for transport.
    The ANSI/WSC standard PST 2000-2005 prescribes minimum performance
and construction requirements for pressurized storage tanks for service
in water well systems with a maximum factory pre-charge pressure of 40
psig (280 kPa), to be operated in ambient air temperatures up to 120
[deg]F (49 [deg]C), with

maximum working pressures not less than 75 psig (520 kPa) and not
greater than 150 psig (1,000 kPa) and tank volumes not exceeding 120
gallons (450 L). The standard was developed by a group of WSC members
comprised of leading U.S. manufacturers of pressurized water storage
tanks for water wells to define and promote--through voluntary written
standards--minimum performance and construction requirements for
pressurized water storage tanks for service in water well systems.
Aligning the HMR with this industry standard will provide minimum
requirements for pressurized water storage tanks for water wells that
provide at least an equivalent level of safety as currently provided in
the HMR.
    The revised requirements for water pump system tanks in this final
rule authorize tanks to be tested to the manufacturer's specified
maximum working pressure instead of the current one size fits all
requirement of 100 psig. Further, it allows water pump system tanks to
be charged with helium in addition to the currently authorized
nitrogen. The requirements in this final rule allow additional
flexibility for manufacturers compared to current requirements.
Therefore, PHMSA does not expect this amendment to impose costs. PHMSA
received one comment in support of this proposal from Worthington
Cylinder.
    In the NPRM, we proposed to change the pneumatic test requirement
from 100 psig to the manufacturer's specified maximum working pressure
because the industry standard allows for maximum working pressures
greater than 100 psig (i.e., up to 150 psig as stated above). In this
final rule, we will specify that the pneumatic test may not exceed 150
psig, which aligns with ANSI/WSC PST 2000-2005 maximum working pressure
for a water pump system tank. Pneumatic pressure tests present
additional risks to testing personnel, and this modification is
intended to reduce risk by clarifying the maximum test pressure allowed
while remaining aligned with the industry standard.
    We are making several additional editorial changes to the layout
and language of Sec.  173.306(g) in order to clarify the intent of the
provision. Specifically, we are modifying the introductory paragraph of
Sec.  173.306(g) to clarify our intent to allow the tanks to be filled
with air, nitrogen, or helium up to 40 psig at time of manufacture,
referred to in ANSI/WSC PST 2000-2005 as a ``pre-charge.'' Further, we
are replacing the word ``charged'' with ``pre-charge'' throughout the
paragraph to clarify that the manufacturer's pre-charge pressure is the
pressure that should be used in calculations, where appropriate.
    We are modifying Sec.  173.306(g)(1) to explain clearly the maximum
allowable working pressure limits of water pump system tanks. The
requirement that these tanks may be operated in ambient air
temperatures of up to 49 [deg]C (120 [deg]F) with a maximum working
pressure not less than 517.1 kPa (75 psig) and not greater than 1034.2
kPa (150 psig) is taken from the ANSI/WSC PST 2000-2005 standard. Our
intent is to impose a limit on the marked maximum working pressure for
a water pump tank system at 150 psig, (i.e., the upper end of the
maximum working pressure), to ensure pneumatic testing is not conducted
above this pressure at time of manufacture to prevent increased dangers
for testing employees. Given that the new MAWP limit in Sec.
173.306(g)(1) aligns with the industry standard and is above the limit
for water distribution piping operations, PHMSA does not believe that
this requirement will introduce any additional burdens on
manufacturers.
    We are removing the phrase ``concave dome tanks'' from Sec.
173.306(g)(3) for clarity because we consider this language to be
redundant to the requirement in Sec.  173.306(g)(1) that requires all
tanks to have heads concave to pressure.
    Finally, we are not adopting proposed paragraph (g)(4), which
discussed a design leakproofness test for composite tanks. We do not
believe that requiring this test for composite tanks is necessary in
the HMR. Our main transportation safety concern with water pump system
tanks remains their burst pressure, and we believe that inclusion of
the proposed design hydrostatic leakproofness test for composite tanks
will increase confusion. All tanks, steel and composite, are subject to
a pneumatic proof pressure test at the manufacturer's maximum allowable
working pressure at time of manufacture (see Sec.  173.306(g)(1)). All
tank designs, both steel and composite, must also have a burst pressure
at least 6x the pre-charge pressure at 21.1 [deg]C (70 [deg]F) or 3x
the manufacturer's specified maximum working pressure, whichever is
greater, as proposed. These modifications to the proposed language are
intended to increase clarity without making any substantive changes to
the provisions proposed in the NPRM.
    In this final rule, PHMSA will adopt provisions of P-1582 as
proposed with the modification noted above.

P-1592

    The CGA submitted P-1592 requesting that PHMSA replace the 2005
edition of CGA S-1.1, Pressure Relief Device Standards--Part 1--
Cylinders for Compressed Gases with the 2011 edition as referenced in
the HMR.
    CGA S-1.1 provides standards for selecting the correct pressure
relief device (PRD) to meet the requirements of Sec.  173.301(f) for
over 150 gases. It provides guidance on when a pressure relief device
can be optionally omitted and when one's use is prohibited, as well as
direction on pressure relief device manufacture, testing, operational
parameters, and maintenance. CGA S-1.1 is available for purchase online
and will be available for public inspection at the Hazardous Material
Information Center after publication of the final rule.
    This minor update to the regulations improves the timeliness and
clarity of industry standards that are incorporated by reference. It
supports the goal of facilitating the use of industry standards and
reducing the burdens associated with references to outdated material.
    Bancroft Hinchey, Worthington Cylinder, NAFED, CGA and FIBA
Technologies submitted comments supporting incorporation by reference
of the 2011 edition of CGA S-1.1. FIBA Technologies additionally
identified an inconsistency with the HMR and new S-1.1 requirements.
FIBA Technologies correctly noted that the requirements for pressure
relief devices in Sec.  173.302a(c)(4)(ii) conflict with the 2011
edition of CGA S-1.1 that we are incorporating by reference in this
rulemaking. Accordingly, we are amending Sec.  173.302a(c)(4)(ii) to
reflect that PRDs are optional for hydrogen tube trailers. Shippers are
not required to install PRDs on tubes (cylinders longer than 12 feet)
shipped in accordance with this paragraph, however their continued use
and installation is authorized. This change maintains regulatory
flexibility and alignment with accepted industry practice. This change
does not impose any new requirements and increases regulatory
flexibility by allowing hydrogen tube trailer shippers the option of
continuing to use PRDs. In this final rule, we are incorporating by
reference CGA S-1.1, 2011 as proposed.

P-1596

    Chemically Speaking, LLC submitted P-1596 which requested that
PHMSA revise the HMR pertaining to salvage drums. Specifically, P-1596
proposed amending Sec.  173.3(d) to allow Class 4 and Class 5 materials
to be placed in salvage cylinders.

    Three commenters commented on this proposal. Dow Chemical Company
and Worthington Cylinder supported the adoption of the petition as
proposed. CGA opposed the adoption of the petition on the basis of
safety, stating that they do not support revising salvage drum
provisions in the HMR to allow Class 4 and Class 5 to be placed in
salvage vessels because chemically reactive materials may produce
pressures exceeding their pressure ratings. CGA suggests that a special
permit or approval should be required for this activity.
    PHMSA response. We agree with Dow and Worthington and do not agree
with CGA's comment. We proposed to allow the use of salvage cylinders
(emphasis added), which are much more robust packagings than the
salvage drums that CGA mentions. PHMSA acknowledges that the NPRM
discussion of this proposal may have led to CGA's overly broad
interpretation PHMSA's intent because we used the term ``drum'' even
though the petition only applies to salvage cylinders. There is
currently no restriction preventing shippers from placing Class 4 and
Class 5 materials in salvage drums. Salvage cylinders are currently
authorized to transport liquefied gases (such as carbon dioxide) and
many toxic gases (Division 2.3). These materials are both high and low
pressure so the salvage cylinders must be constructed and designed to
handle the possible pressures of the packaged materials at temperatures
up to 55 [deg]C. Salvage cylinder design criteria ensure safety and
containment of a leaking cylinder so it can be transported to a
disposal facility. Adding Class 4 and Class 5 materials will not create
any significant change in the risk when using salvage cylinders as long
all the requirements of Sec.  173.3(d) are met. No Class 4 and Class 5
materials can be as toxic as the Division 2.3 or Division 6.1 materials
currently allowed, nor can they generate pressure that would exceed the
pressures of the Division 2.1, 2.2, or 2.3 materials currently allowed.
Thus, we believe adding these materials as authorized in salvage
cylinders will maintain the same level of safety established by the
regulations.
    CGA also suggested allowing Class 4 and Class 5 materials to be
placed in salvage cylinders under the provision of an approval.
    PHMSA response. We believe a requirement to receive an approval to
use a salvage cylinder for Class 4 and Class 5 materials to be
impractical in emergency situations. Additionally, as we have not
identified any increased risk by providing this general allowance,
imposing a burden on users to obtain an approval would also not be
practical. We do not believe there will be any decrease in safety by
allowing shippers to place Class 4 and Class 5 materials in more robust
salvage cylinders. Therefore, we are adopting P-1596 as proposed, and
amending Sec.  173.3(d) accordingly.

P-1622

    Worthington Cylinder submitted P-1622 requesting that PHMSA limit
the internal volume of DOT 39 cylinders containing liquefied flammable
gas to 75 cubic inches (in\3\), to correct an error dating to 2002.
(1) 75 Cubic Inch Limit
    Prior to the publication of HM-220D (67 FR 51626; Aug. 8, 2002),
the HMR restricted the internal volume of DOT 39 cylinders to 75 in\3\
for all non-liquefied flammable compressed gases and the following
flammable liquefied gases: Cyclopropane, ethane, ethylene and liquefied
petroleum gas. In the HM-220 NPRM (63 FR 58460; Oct. 30, 1998), we
proposed to increase the applicability of this restriction to all
flammable liquefied gases, but did not adopt the change on the basis of
negative comments in the HM-220D final rule. The HM-220D final rule,
however, contained a drafting error that removed the 75 in\3\
restriction from liquefied gases completely, which was not our intent.
    Worthington Cylinder submitted P-1622 on July 19, 2013, requesting
that PHMSA impose a volume restriction of 75 in\3\ on DOT 39 cylinders
containing the liquefied gases cyclopropane, ethane, ethylene, and
liquefied petroleum gas. On October 10, 2014, Worthington Cylinder
submitted a supplement to P-1622, requesting that PHMSA restrict the
volume of DOT 39 cylinders containing any liquefied flammable gas to 75
cubic inches. In the NPRM, we proposed to adopt this second proposal
and restrict the volume of DOT 39 cylinders containing any liquefied
flammable gas to 75 cubic inches.
    CGA and Worthington Cylinder submitted comments supporting our
proposed action to restrict the volume of DOT 39 cylinders containing
any liquefied flammable gas to 75 cubic inches. We received comments
from Worthington Cylinder, Ford Motor Company, Amtrol, Chemours,
COSTHA, and Honeywell requesting that we create an exception to the
proposed 75 in\3\ limit for ASHRAE A2L ``mildly flammable'' gases. We
did not receive any comments directly opposed to the creation of a
general 75 in\3\ limit for liquefied flammable gases in DOT 39
cylinders. The commenters explained that, in the years since the 75
in\3\ restriction was inadvertantly deleted, they have begun safely
transporting certain Division 2.1 refrigerant gases in DOT 39 cylinders
larger than 75 in\3\. They also submitted technical data describing the
properties of ASHRAE A2L ``mildly flammable'' gases and demonstrated
the performance of a DOT 39 cylinder with a capacity over 75 in\3\
filled with an A2L gas in a bonfire test.
    PHMSA response. In this final rule, we are modifying our proposed
change to Sec.  173.304a and imposing a 75 in\3\ limit on the capacity
of DOT 39 cylinders containing the following liquefied flammable gases:
Cyclopropane, ethane, ethylene and liquefied petroleum gas. This course
of action will correct the inadvertent error we made in HM-220D and
aligns with PHMSA's safety advisory notice published April 24, 2017
(PHMSA-2016-14; 82 FR 18967). This will also sufficiently address the
economic concerns raised by Worthington Cylinder, Ford Motor Company,
Amtrol, Chemours, COSTHA, and Honeywell regarding the applicability of
the 75 in\3\ limit for hydrofluoroolefin and dihalogenoalkane
refrigerants.
(2) Chemicals Under Pressure
    Dow Chemical Company submitted a comment requesting clarification
about the size limitation for chemicals under pressure in Sec.
173.302a(a)(3).
    PHMSA response. The limit is only intended to apply to Division 2.1
(flammable gas) chemical under pressure. However, as we noted in the
NPRM, the 50 L limit is much larger than the maximum size authorized
for the DOT 39 specification in Sec.  178.65. This discrepancy was an
unintentional outcome of a harmonization effort with international
requirements for non-refillable cylinders, which allow larger sizes
than the HMR allow (see Docket No. PHMSA-2012-0027 (HM-215L); 78 FR
988). To reduce confusion introduced by the conflict of the 50 L
quantity in Sec.  173.302a(a)(3) and the capacity limts of the
specification, we are deleting the reference to ``50 L (3050 in\3\)''
and replacing it with reference to the DOT 39 specification capacity
limits--1526 in\3\ for a service pressure of 500 psig or less, and 277
in\3\ for a service pressure of greater than 500 psig.

P-1626

    The CGA submitted P-1626 requesting that PHMSA incorporate by
reference (IBR) CGA C-1, Methods for Pressure Testing Compressed Gas
Cylinders, Tenth Edition (2009) and revise the regulations regarding
the

retesting of cylinders by the hydrostatic test as they are not only
unclear to requalifiers, but also missing necessary information
rendering the regulations unenforceable. Although the petition proposed
the Tenth Edition, currently there is an Eleventh Edition (2016)
available. In the NPRM, PHMSA proposed to incorporate by reference this
most current version and requested comment regarding this action. We
received no adverse comments related to adoption of the newest edition
(i.e., CGA C-1-2016 (11th Ed.)) of the standard versus the Tenth
Edition. However, we did receive numerous comments regarding the
incorporation by reference of CGA C-1-2016 (11th Ed.) (``CGA C-1'') and
associated revisions, which we will discuss in depth as follows.
    In this final rule, PHMSA is adopting clarifying language and
incorporating by reference the CGA C-1 standard, as proposed in P-1626.
CGA C-1 provides more detailed instructions and illustrations for use
by cylinder requalifiers and manufacturers than what is possible in the
HMR and addresses the deficiencies detailed in the petition. This
incorporation by reference applies to the following sections:
Sec. Sec.  178.36, 178.37, 178.38, 178.39, 178.42, 178.44, 178.45,
178.46, 178.47, 178.50, 178.51, 178.53, 178.55, 178.56, 178.57, 178.58,
178.59, 178.60, 178.61, 178.65, 178.68, 180.205, and 180.209. The
incorporation of CGA C-1 supports the goal of increasing compliance and
improving overall safety as its reference increases clarity and
provides enhanced guidance compared to the current language in the HMR.
Cylinder requalifiers and manufacturers must comply with CGA C-1
requirements for pressure testing cylinders, as well as equipment
accuracy and calibration. Specific clarifications include instructions
for performing volumetric expansion tests using both the water-jacket
and direct expansion methods, as well as a provision for retesting in
case of equipment failure or operator error and re-naming the
``hydrostatic test'' paragraph to ``pressure test'' to align more with
industry accepted nomenclature. PHMSA believes that CGA C-1's inclusion
of ``operator error'' as a condition allowing a repeated test at a
higher pressure will prevent the condemnation of cylinders that are
safe for continued use. Revising the HMR to incorporate by reference
CGA C-1 will provide the desired clarification without imposing
requirements that are potentially costly or unnecessarily difficult.
(1) Response to Hydro-Test Products
    We received numerous comments regarding incorporation by reference
of CGA C-1, and about interpretation of CGA C-1 requirements. Hydro-
Test Products \6\ submitted a comment requesting clarification of CGA
C-1 requalification requirements compared to the current
requalification requirements in part 180, subpart C, of the HMR. Hydro-
Test Products states,
---------------------------------------------------------------------------

    \6\ PHMSA notes that Jeff Elliot, Noble Gas Solutions, Anthony
King, W Andrews, and Scuba Do submitted comments supporting the
Hydro-Test Products comment and opposing the incorporation of CGA C-
1. While the discussion below focuses on the specific comments from
Hydro-Test Products, it also addresses the subject matter raised by
these other comments supporting the Hydro-Test Products comment.

    The authors of the CGA C-1 pamphlet have included definitions
and examples of calibration and accuracy for Expansion Indicating
Devices (EID) and Pressure Indicating Devices (PID) that will
restrict most all current licensed cylinder re-qualifiers from
performing cylinder re-qualification. Furthermore, there are
statements in the C-1 that discriminate against procedures and
equipment components that have been utilized in a safe, consistent
---------------------------------------------------------------------------
and accurate manner for many years.

    PHMSA response. We disagree with Hydro-Test Products and address
the issues they raise below.
(a) Expansion Indicating Device Accuracy
    Hydro-Test Products describes a burette arrangement with 4 burettes
with full scales of 0-25, 0-50, 0-125 and 0-360 cubic centimeters (cc)
and explains their belief that incorporation by reference of CGA C-1
will significantly restrict the usable range of the burettes to half of
the burette's scale, instead of the much broader range that they
believe are authorized under the current HMR.
    PHMSA response. Hydro-Test Products understanding of the HMR's
current requirements is not correct. The HMR currently require use of
burettes in the same manner prescribed in CGA C-1. Hydro-Test Products
misunderstanding appears to be grounded in the final rule published on
May 28, 1996, known as HM-220A, (61 FR 26750). HM-220A created the
requirement that expansion indicating devices (EID), such as burettes
or scales, must be certified as having an accuracy of 0.5
percent, of its full range, and must be accurate to 1.0
percent of the total expansion of any cylinder tested or 0.1 cubic
centimeter, whichever is larger. These accuracy requirements, as
discussed in the HM-220A final rule (61 FR 26751), are separate and
distinct from the requirement that the EID permit reading to 1 percent of the total expansion. The reading requirements are
intended to address the resolution of the EID, which is not the same as
the accuracy of the EID. In the example of the burette with a full
scale of 50 cc, with an accuracy grade of 0.5 percent and
increments of 0.1 cc (mid-point interpolation allowed to 0.05), the
resolution would permit reading down to 5 cc (i.e., interpolation to
0.05 is 1 percent of 5 cc), but the accuracy of the device would not. A
burette with a full scale of 50 cc and full-scale accuracy of 0.5 percent has an expected deviation of 0.25 cc. The
device may only be used to measure total expansion greater than 25 cc,
because at total expansions lower than 25 cc, the expected deviation
will be greater than 1 percent of the total expansion.
Using the 5 cc example, a 0.25 cc deviation (i.e., the expected
deviation for a 50 cc burette with an accuracy grade of 0.5
percent) at a total expansion of 5 cc would be a 5% deviation, and
would not meet the requirement that the EID is accurate to 1% of the total expansion.
    Moreover, we do not agree that incorporation by reference of CGA C-
1 will impose new cost burdens upon cylinder requalifiers because the
current regulatory standard has been in place since 1996, and the
requirements will not change with incorporation by reference of CGA C-
1. Hydro-Test Products states that a similar issue exists for
requalifiers using a scale as their EID. Our response is the same: The
current regulatory standard has been in place since 1996, and the
requirements will not change with incorporation by reference of CGA C-
1.
(b) Total and Permanent Expansion Accuracy
    Hydro-Test Products asks how EIDs can be used to measure permanent
expansion when that permanent expansion is a much lower value that the
total expansion, i.e. the permanent expansion is out of the range
allowed for the total expansion.
    PHMSA response. Hydro-Test Products is correct that permanent
expansion values are much lower than total expansion values. The HMR
has always accepted a greater accuracy deviation for permanent
expansion, and this does not change in CGA C-1. Accuracy requirements
for EIDs continue to be expressed in terms of the total expansion
value.
(c) Foreknowledge of Total Expansion
    Hydro-Test Products asks, ``[s]ince there is no indication of the
total expansion value on DOT specification

cylinders, how is a re-qualifier supposed to know what burette or scale
is applicable and within the proposed regulations for a given test?''
    PHMSA response. If a requalifier is completely unaware of the
approximate expected total expansion for a cylinder, the requalifier
may pressurize the cylinder at or below 90 percent of test pressure,
which will give an approximate value for total expansion, allowing the
requalifier to select the proper EID for the test. If the operator errs
and the cylinder is tested using an EID that cannot measure the total
expansion to 1 percent, he or she may repeat the test up to
two times, in accordance with CGA C-1 section 5.7.1. Note that
pressurizing the cylinder at or below 90 percent of test pressure does
not constitute a test.
(d) Pressure Indicating Device Accuracy
    Hydro-Test Products describes a scenario with four pressure
indicating devices (PIDs) with the understanding that CGA C-1 will
significantly limit the usable range of the gauges.
    PHMSA response. We acknowledge that there are other ways to
demonstrate compliance with the accuracy requirements for PIDs (e.g.
certifying gauges at pressures lower than their manufacturer's rated
full scale). We believe this practice is in accordance with the HMR and
with CGA C-1 because a gauge calibrator has, in effect, certified a
gauge to better than a 0.5 percent full scale accuracy when
he or she calibrates the gauge to demonstrate 1 percent
accuracy at points lower than the normally usable range of the gauge
based on the manufacturer's rated accuracy. The 1 percent
accuracy requirement is only a minimum standard, and gauge
manufacturers or other entities certifying the accuracy are free to
demonstrate that the gauge meets the 1 percent requirement
at other, lower points on the gauge.
    The examples provided in CGA C-1 are only a guide, and should not
be used to prevent the use of PIDs at lower pressures provided the
gauge calibrator documents the calibration points on the calibration
certificate. The minimum accuracy and readability standards are such
that it limits the use of any PID to (the upper) half the gauge,
however, there is no limitation on using a gauge certified to be more
accurate across its full range, thus allowing broader use of the gauge.
PHMSA reviewed this practice in Letter of Interpretation Ref. No. 14-
0112, and at this time we have no reason to believe that this practice
is unsafe. To clarify our intent further to continue to allow this
practice, in this final rule we are not requiring compliance with CGA
C-1 paragraph <IP_ADDRESS>, which discusses accuracy requirements for PIDs,
if the required accuracy of the PID can be demonstrated by other
recognized means such as calibration certificates.
    Rather we are maintaining 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. Regardless of the method used to determine the usable
range of the gauge, the cylinder requalifier must verify that the
system is accurate to within 1 percent of the test pressures to be
tested that day, as provided in CGA C-1 paragraph 5.5.
(e) Reference Zero Expansion
    Hydro-Test Products requests clarification of the term ``reference
zero expansion'' in CGA C-1, sections 3.2.22.
    PHMSA response. In the verification process, it is critical that
the calibrated cylinder show zero expansion to indicate that the system
set-up is accurate and ready for testing. The term ``reference zero
expansion'' is intended to clarify that when reading the calibrated
cylinder's permanent expansion during verification, an expansion
reading of 0.1cc or 0.1 percent of total
expansion, whichever is larger, is accepted as zero.
(f) Daily Verification
    Hydro-Test Products states that the requirement to verify all test
equipment to be used that day is impossible for those companies that
are utilizing burette systems on the volumetric tester and generally
unnecessary.
    PHMSA response. We disagree. This is a long-standing requirement
that is currently found in the HMR in Sec.  180.205(g)(4). All PIDs,
EIDs, and water jackets that are to be used that day must be verified
under the current requirements of the HMR. We do not believe any
additional costs will be imposed by incorporating CGA C-1 because this
industry standard has the same requirements as are already required for
cylinder requalifiers under the HMR.
(g) Calibrated Cylinders as Surge Tanks
    Hydro-Test Products and Galiso question the reasoning for CGA C-1's
prohibition on the use of a calibrated cylinder as a ``surge tank''
used to slow pumping speeds when testing smaller cylinders.
    PHMSA response. Observations from PHMSA field investigators suggest
that industry already largely complies with this requirement. We have
safety concerns that exposure to unregulated pressure surges and high
temperatures may render the calibrated cylinder unsuitable for its
intended purpose. If repeatedly exposed to unregulated pressure surges,
the calibrated cylinder may experience additional permanent expansion,
rendering it incapable of being used to verify the system's accuracy on
a daily basis. The daily verification process depends on the calibrated
cylinder giving a precisely known expansion value at a given pressure.
If the calibrated cylinder begins stretching too much, for example, a
cylinder requalifier may adjust the equipment so that the reading
returns to the expected value, not realizing that he has just brought
his equipment out of alignment in his attempt to calibrate with an
overstretched cylinder. This would cause inaccurate tests whenever that
calibrated cylinder is used to verify the system before a day of tests.
(h) Conclusion
    Finally, Hydro-Test Products states, ``[a]s we have hoped to have
presented in these comments, the incorporation of the C-1 into the
regulations will only confuse cylinder re-qualifiers more, while
imposing nearly impossible accuracy requirements at a greater cost with
absolutely no benefit in safety.''
    PHMSA response. We disagree with Hydro-Test Products' conclusion.
As we have shown, incorporation of CGA C-1 will not impose additional
regulatory burdens on requalifiers. CGA C-1 combines the HMR's current
regulatory requirements for pressure testing with diagrams,
illustrations, step-by-step guidelines, trouble-shooting procedures,
and technical appendices that provide requalifiers with all the
information they need to requalify cylinders safely and successfully.
The creation of flexibility for reference zero expansion will decrease
the time wasted by requalifiers calibrating their systems every day
without compromising accuracy. PHMSA believes, based on experience
conducting compliance inspections at cylinder requalification
facilities, that the additional guidance provided by CGA C-1 (diagrams,
troubleshooting guides, technical appendices) will encourage compliance
with cylinder requalification standards.

(2) Response to Other Commenters
(a) System Failure or Operator Error
    FIBA submitted a comment requesting that we reevaluate the
requirements related to system failures or operator error during the
pressure test required after cylinder manufacture.
    PHMSA response. We agree that the requirements need further
clarification. It was our intention to align with the requirements in
CGA C-1, section 5.7.2 for cylinder manufacture. In the event of
equipment failure or operator error, cylinders may be repeat tested
more than twice at time of manufacture, as long as the actual test
pressure does not exceed 110 percent of the minimum test pressure and
the stresses developed in the cylinder remain within its specification
and design limitations. Therefore, we are inserting a reference to that
provision in each cylinder manufacture pressure testing paragraph. Note
that this does not apply to 3AL cylinders, which, due to the
differences in ductility between aluminum and steel, are limited to a
single repeat test.
(b) Clarification of Sec.  178.42(f)
    COSTHA submitted a comment requesting grammatical changes to the
proposed Sec.  178.42(f) to clarify our intent. Section 178.42
specifies two tests for DOT 3E cylinders. One cylinder from each lot
must be burst tested, and must burst at a pressure of 6,000 psig
without fragmenting or otherwise showing lack of ductility. Then
following a successful burst test, each remaining cylinder in the lot
must be examined under pressure of at least 3,000 psig, and not above
4,500 psig, and show no defect. The cylinder manufacturer may only
examine the cylinders at a pressure of 3,600 psig or greater if the
cylinder that was burst-tested at 7,500 psig or greater.
    PHMSA response. We agree with COSTHA's comment that the proposed
language in Sec.  178.42(f)(3)(ii) was ambiguous. In this final rule,
we are reverting the language in Sec.  178.42(f) to the previous layout
and language and adding the incorporation of CGA C-1. In our attempt to
clarify the requirements in Sec.  178.42(f) we inadvertently made them
more ambiguous.
(c) CGA C-1.1
    Hydro-Test Products, Bancroft Hinchey, ICT, Noble Gas Solutions,
and FIBA noted that the CGA C-1.1 training material we cited in Sec.
180.205(j), has been retracted by CGA and requested that we remove
reference to it.
    PHMSA response. We agree with the commenters and will remove
reference to CGA C-1.1 from Sec.  180.205(j), as it no longer applies
as a resource.
(d) Burst Testing Accuracy
    Worthington Cylinder submitted a comment requesting clarification
about whether CGA C-1 accuracy requirements apply to PIDs used when
burst testing cylinders during manufacturing.
    PHMSA response. The answer is yes. In this final rule, we will
modify the relevant sections of the part 178 specifications for
cylinders to indicate that PIDs used for burst tests must meet the
requirements of CGA C-1.
(e) Reference Zero Expansion
    Galiso submitted a comment requesting that we accept a value within
1 percent of readability as zero for daily verification.
PHMSA does not agree. The allowance of .1 percent of total
expansion will decrease time spent by requalifiers during daily
verification while ensuring that their system continues to meet
accuracy requirements. PHMSA will not consider a new ``zero'' standard
in this final rule.
(f) Repeat Tests for System Failure or Operator Error
    Galiso submitted a comment requesting an explanation for the
limitation of two repeat tests in the case of system failure or
operator error. When a cylinder is pressurized, it expands. This
property is the basis of the volumetric expansion testing program.
Volumetric expansion testing measures the volume of the cylinder at
test pressure (elastic expansion), and compares it to the volume of the
cylinder after pressure is removed (permanent expansion). When
permanent expansion is more than 10 percent (or 12 percent for certain
cylinders) of elastic expansion, the cylinder must be condemned. If a
cylinder is pressurized to over 90 percent of test pressure and then
the system fails or the operator errs, it will not return to its
original state, rather it will exhibit permanent expansion and reduced
expandability because the metal has been stretched. When the test is
repeated the next day, the cylinder will exhibit less permanent
expansion than the day before, because it started the test in an
expanded state. PHMSA is concerned that allowing more than two repeat
tests cycles will allow cylinders that should have been condemned to
re-enter transportation.
(3) Corrections
(a) DOT 39 Burst Test
    In the review of the NPRM, PHMSA determined that we inadvertently
removed the requirements for burst-testing DOT 39 cylinders from Sec.
178.65(f). In this final rule, we are re-inserting burst test
requirements with language incorporating CGA C-1 calibration and
accuracy requirements for burst testing into Sec.  178.65(f).
(b) Incorrect Usage of the Word ``Condemn''
    In the review of the NPRM, PHMSA determined that we inadvertently
replaced the word ``rejected'' with ``condemned'' in several cylinder
manufacture pressure testing sections, specifically Sec. Sec.  178.46,
178.47, 178.55, 178.56, and 178.65. This was not our intent. In this
final rule, we will maintain the HMR's existing instructions for
cylinders rejected during manufacture.
(4) Pneumatic and Hydraulic Proof Pressure Tests
    CGA C-1 provides instructions for conducting proof pressure tests
both pneumatically (gaseous-based system) and hydraulically (liquid-
based system). For the purposes of part 178, subpart C, a manufacturer
may choose either system when a proof pressure test is authorized.
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.
Manufacturers must take this risk into account and develop systems to
prevent the injury or death 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.

P-1628

    CGA submitted P-1628 requesting that PHMSA incorporate by reference
(IBR) CGA C-3-2005, Reaffirmed 2011, Standards for Welding on Thin-
Walled, Steel Cylinders, Seventh Edition into the HMR. Presently, the
HMR incorporate the Fourth Edition of this standard, CGA C-3-1994. This
publication contains information on welding process qualification,
welding operator qualifications, tensile testing, bend testing, and
radiographic inspection. The changes between the Fourth Edition and the
Seventh Edition were predominantly editorial or technical in nature.
The significant technical changes are summarized as follows and

can be reviewed in detail in the docket to petition P-1628: \7\
---------------------------------------------------------------------------

    \7\ PHMSA Docket ID: PHMSA-2013-0278.
---------------------------------------------------------------------------

     Added section to the testing criteria to employ the use of
macro etch samples in lieu of weld guided bend test and weld tensile
testing when the cylinder size would not permit securing of proper size
specimens.
     Clarified the weld bend testing procedure, weld bend
testing tooling, and proper clearances that are required in the
tooling.
     Clarified definitions for the welding procedure
qualification and the welding operator weld qualification.
     Added a tolerance section that indicates the plus and
minus tolerances when a specific dimensional tolerance is indicated in
the publication.
     Added drawings to illustrate different weld joint designs.
    Bancroft Hinchey, Worthington Cylinder, NAFED, and CGA submitted
comments supporting the incorporation of the Seventh Edition of CGA C-
3. Therefore, in this final rule, PHMSA is incorporating by reference
CGA C-3-2005, Reaffirmed 2011, as proposed.
    Bancroft Hinchey requested clarification of training requirements
for cylinder requalifiers.
    PHMSA response. Cylinder requalifiers meet the definition of
``hazmat employee'' found in Sec.  171.8. All hazmat employees must be
trained in accordance with 49 CFR part 172, subpart H, including
function specific training. An employee working as a cylinder
requalifier must be trained to perform that job function properly,
including visual inspection of cylinders, but would not necessarily
need welding training unless also performing a welding function subject
to the HMR.

P-1629

    The CGA submitted P-1629 requesting that PHMSA incorporate by
reference (IBR) CGA C-14-2005, Reaffirmed 2010, Procedures for Fire
Testing of DOT Cylinder Pressure Relief Device Systems, Fourth Edition,
into the HMR. Presently, the HMR incorporates the First Edition of CGA
C-14-1979. Since the incorporation of this edition, CGA has revised the
publication in 1992, 1999, 2005, and reaffirmed the publication in
2010.
    This standard describes test procedures and apparatus for fire
testing compressed gas cylinder safety (pressure) relief devices as was
required by former Sec.  173.34(d) and current Sec.  173.301(f) of the
HMR. The procedures are designed to provide a means of testing to DOT
requirements anywhere with reliable test data and repeatable test
results. The changes from the 1979 First Edition to the 2005 and
Reaffirmed 2010 editions of CGA C-14 were predominantly editorial or
technical in nature. The significant technical changes are summarized
as follows and can be reviewed in detail in the docket to petition P-
1629: \8\
---------------------------------------------------------------------------

    \8\ PHMSA Docket ID: PHMSA-2014-0012.
---------------------------------------------------------------------------

     Permitted the use of an alternate lading. If the intended
lading would present an increased safety hazard during the test
procedure (such as the use of poisonous or flammable gas), the cylinder
may be charged with a typical liquefied or non-liquefied gas. Gases
with essentially similar physical properties may be classified as
typical.
     Added the Bonfire Test Method to the publication. This
permitted the Board of Explosives (BOE) test method to be used to
qualify pressure relief device systems. The Bonfire Test Method was
successfully used to qualify pressure relief device systems for
decades.
     Clarified what information is to be recorded before and
during the actual test.
     Increased the water capacity of a cylinder that can be
fire tested from 500 pounds water capacity to 1000 pounds water
capacity to permit a test method for all DOT 4-series cylinders.
    Worthington Cylinder and CGA submitted comments supporting the
adoption of CGA C-14-2005, Reaffirmed 2010. Therefore, in this final
rule, PHMSA is adopting CGA C-14-2005, Reaffirmed 2010 as proposed.

P-1630

    CGA submitted P-1630 requesting that PHMSA revise the HMR
requirements for DOT 4L welded insulated cylinders. Specifically, the
CGA requested PHMSA make two changes to add a definition of
``recondition'' to Sec.  180.203 and amend paragraphs Sec. Sec.
180.211(c) and 180.211(e) to clarify when a hydrostatic test must be
performed on the inner containment vessel after the DOT 4L welded
insulated cylinder has undergone repair.
    CGA submitted a comment to the NPRM requesting that we take no
action on their petition. We received no other comments to the proposed
changes based on P-1630, and therefore, we see no need to revise the
HMR based on this petition and will not adopt any changes proposed by
P-1630.

V. Special Permits and Comments Received

    This final rule addresses one special permit. In the ANPRM, PHMSA
considered proposing revisions to adopt certain special permits into
the HMR. Specifically, PHMSA proposed changes based on DOT-SPs 12929,
13318, and 13599. In the NPRM, PHMSA did not propose changes in
association with these special permits because: (1) DOT-SP 12929 was
determined not suitable for adoption under rulemaking HM-233F (80 FR
5340; January 30, 2015); and (2) DOT-SPs 13318 and 13599 were adopted
under HM-233F (81 FR 3635; January 21, 2016).
    In the NPRM, we proposed to adopt provisions from DOT-SP 14237 to
allow for the transportation of adsorbed gases in DOT specification
cylinders by creating a new section, Sec.  173.302d, in the HMR. The
HMR currently only authorizes the transportation of adsorbed gases in
UN pressure receptacles under the provisions of Sec.  173.302c. The use
of DOT cylinders containing adsorbed gases is currently authorized
under various special permits. In the NPRM, we proposed to authorize
the transportation of adsorbed gases in DOT-3E1800, DOT-3AA2015, and
DOT-3AA2265 cylinders with a capacity between 0.4 and 7.3 liters.
Additionally, the proposed Sec.  173.302d included a requirement to
place the DOT specification cylinder into a non-DOT specification full-
opening, hinged-head or fully removable head, steel overpack cylinder
constructed to meet the requirements of ASME Code Section VIII,
Division 1 with a minimum design margin of 4 to 1.\9\
---------------------------------------------------------------------------

    \9\ These are all provisions carried over from DOT-SP 14237.
---------------------------------------------------------------------------

    We received several comments regarding this proposal. Praxair
submitted a comment requesting that, rather than adopting DOT-SP 14237,
we harmonize DOT cylinder adsorbed gas requirements with UN pressure
receptacle requirements found in Sec.  173.302c, authorize all gases
for use as adsorbed service instead of the ``short list'' proposed in
Sec.  173.302d, eliminate the proposed overpack cylinder requirement,
and, if we did not eliminate the overpack requirement, require the
overpack be tested in a DOT-approved facility subject to the
requirements of part 107, subpart I. CGA submitted a comment suggesting
that rather than adopt the proposed special permit, we should align the
proposed requirements for adsorbed gases in DOT cylinders in Sec.
173.302d with the existing requirements for adsorbed gases in UN
pressure receptacles currently found in Sec.  173.302c. COSTHA
submitted a comment supporting the adoption of requirements for
adsorbed gases in DOT cylinders, but noted that some of the gas entries
we listed in the

proposed table in Sec.  173.302d had separate UN ID numbers for their
adsorbed version in the Sec.  172.101 Hazardous Materials Table that
should be cited instead of the non-adsorbed gas entry.
    Entegris submitted a comment requesting that rather than adopting
DOT-SP 14237, we should adopt DOT SP-16485, which allows for
transportation of adsorbed gases in DOT-3AA and DOT-3E cylinders in a
manner harmonized with the current requirements for UN pressure
receptacles in Sec.  173.302c. Entegris noted that the overpack
requirement in DOT-SP 14237 was created to address the unique risks
associated with transportation by aircraft, and presents a significant
obstacle to efficient transportation by other modes. They noted that
Sec.  173.302c does not require the use of overpacks for UN pressure
receptacles containing adsorbed gas, nor does DOT-SP 16485.
    PHMSA response. We appreciate the comments we received on this
topic. In this final rule, we are not adopting DOT-SP 14237, nor are we
inserting requirements for adsorbed gases in DOT specification
cylinders into the HMR in Sec.  173.302c. PHMSA's decision is based on
the lack of consensus on this subject and technical concerns we have
surrounding the modal requirements, minimum test pressure criteria, and
authorized requalification. There are multiple existing DOT SPs that
authorize the transportation of adsorbed gases in DOT specification
cylinders. These permits authorize different adsorbed gases and utilize
different DOT specification cylinders to contain the substrate and
adsorbed gas, and have different operational controls. Incorporating
the provisions of multiple special permits that authorize different
materials, multiple specification and non-specification cylinders, and
have differing operational controls, is challenging for PHMSA to
attempt at the final rule stage without soliciting comments on the
regulatory solution that melds the provisions and conditions of
multiple permits together. The incorporation of adsorbed gases presents
additional difficulties due to the risks presented by the highly toxic
nature of the gases currently transported in adsorbed form, leading us
to proceed with caution in adopting a standard into the HMR.
    Therefore, PHMSA believes that the most appropriate way to
authorize adsorbed gases in DOT specification cylinders in the HMR is
to conduct a more thorough review of existing systems authorized by
special permit and propose a solution in a separate rulemaking, rather
than risk creating imperfect regulatory requirements. We will further
evaluate international standards for adsorbed gas transportation and
existing DOT special permits for determination on how best to adopt
provisions for adsorbed gases in DOT specification cylinders into the
HMR. Adsorbed gases may continue to be transported in UN pressure
receptacles in accordance with existing instructions in Sec.  173.302c,
or in DOT cylinders under the terms of a special permit. We will
consider revisiting this issue in a future rulemaking.

VI. Agency Initiated Editorial Corrections

    PHMSA regularly reviews and revises the HMR to correct errors and
clarify any regulations that are unclear or confusing. PHMSA is making
the following changes in this final rule.

Section 107.803

    Section 107.803 provides approval procedures for independent
inspection agencies (IIA) conducting cylinder inspections and
verifications as required by parts 178 and 180. In its application for
approval status, the IIA must provide information, including a detailed
description of its qualifications and ability both to perform and
verify inspections. However, at present, the application information
requirements of Sec.  107.803(c)(3) only reference part 178. In the
NPRM, PHMSA proposed to revise Sec.  107.803(c)(3) to include part 180,
subpart C, for consistency.
    We received one comment on this topic. Bancroft Hinchey supports
this revision. Therefore, in this final rule are adopting this change
as proposed in the NPRM.

Section 107.805

    Section 107.805 provides approval procedures for persons to
inspect, test, certify, repair, or rebuild a cylinder in accordance
with the HMR. PHMSA is revising the requirements for application for
approval of cylinder requalifiers to include a reference to the option
of having a mobile cylinder requalification unit (i.e., a mobile unit).
See Sec.  180.203 for further discussion.
    We received one comment on this topic. Bancroft Hinchey supports
this revision. Therefore, in this final rule we are adopting this
change as proposed in the NPRM.

Section 178.70

    Section 178.70 provides approval for the manufacture of UN pressure
receptacles (i.e., cylinders). Currently, Sec.  178.70(d) restricts the
user (manufacturer) from the flexibility that is provided in the UN/ISO
standards. The regulation as constructed results in additional cost and
delay without any added safety. The UN/ISO standards are developed
based on performance testing and include adequate testing for a wide
range of design-type modifications. All UN/ISO standards to which the
original design type conforms permit certain modifications to an
approved design type. PHMSA has received several requests to revise
this regulation to allow an authorized manufacturer to benefit from the
UN Model Regulations and produce UN/ISO cylinders. In the NPRM, PHMSA
proposed to adopt language consistent with UN/ISO standards to reduce
the need for approvals.
    We received one comment on this topic. Bancroft Hinchey supports
this revision. Therefore, in this final rule we are adopting this
change as proposed in the NPRM.

Section 180.203

    Section 180.203 specifies definitions that apply to cylinder use,
qualification, and maintenance. In the NPRM, PHMSA proposed two
revisions to definitions in Sec.  180.203. In this final rule, we are
adopting the definition for ``mobile unit'' with modifications based on
comments received, and we are not adopting a new definition for ``proof
pressure test.''
(1) Define and Adopt ``Mobile Unit'' Requalification Operations
    The hazardous materials program procedures of 49 CFR part 107 for
approval of cylinder requalifiers do not specify the option of a
``mobile cylinder requalification unit.'' The intent of this type of
approval is to allow a cylinder requalifier to perform its requalifying
function away from the primary place of business to better serve
cylinder owners who need requalification testing and inspection of
cylinders. In the NPRM, we proposed to limit the operations of a mobile
unit to a 100-mile radius from the primary place of business. Eleven
commenters objected to this limit based on economic, safety, and
fairness grounds.
    PHMSA response. PHMSA will not place a distance limit on the
operations of a mobile unit. However, an applicant for a mobile
requalifier identification number (RIN) must specify the geographic
area(s) in which they are requesting approval to operate. The
requirement to provide geographic information on the operating range of
a mobile unit is a part of the current approval process for mobile
units. However, it is not codified in the language of Part 107 for
cylinder

requalification approvals. The intent of this final rule is to codify
the geographic information requirement in the text of part 107 to
increase clarity, not create a new requirement. A mobile cylinder
requalifier must adhere to the requirements in a PHMSA-issued approval
letter to operate. Note that a mobile unit owned or operated by a
previously approved requalifier must still receive a separate approval.
(2) Revise Definition of Proof Pressure Test for Cylinders
    The HMR no longer prescribe modified hydrostatic pressure testing,
which has been and continues to be the method of low-pressure testing
of fire extinguishers.\10\ In the NPRM, we proposed to modify the
definition of ``proof pressure test'' to indicate that it could be
performed with either liquid or a gas. We received 9 comments opposed
to this change, and no comments in support.
---------------------------------------------------------------------------

    \10\ PHMSA removed this from the HMR under HM-220D (67 FR
51626).
---------------------------------------------------------------------------

    Our description of the advantages of pneumatic, or gas-based, proof
pressure testing in the NPRM was not entirely correct. In certain
instances, pneumatic testing may not be faster, less expensive, less
corrosive to the cylinder, or less environmentally harmful than
hydrostatic testing. Pressurizing a cylinder to test pressure and then
de-pressurizing it with air or another gas may take significantly
longer than using water. Regarding corrosion concerns, use of
compressed air for a pneumatic proof pressure test will generally
introduce water into the cylinder, and use of dry gases would generally
be cost-prohibitive except in very limited circumstances. Regarding
environmental concerns, as several commenters noted, many cylinder
requalifiers recycle the water they use.
    PHMSA response. When we removed the modified hydrostatic pressure
test from the HMR and added the proof pressure test into part 180, we
intended that the test be conducted with a liquid, except in special
circumstances subject to a special permit. We do not believe that a
general authorization for pneumatic proof pressure tests for cylinder
requalification is in the public interest. Companies requesting
authorization to perform pneumatic proof pressure tests for cylinder
requalification may request special permits that detail the methods put
in place to prevent death and serious injury in the event of a cylinder
rupture at test pressure (i.e., much more energy is needed to
pressurize a cylinder with a gas than liquid, thus presenting a safety
risk to persons performing the test should a rupture occur). Therefore,
we will not adopt the proposed modified definition of a proof pressure
test in Sec.  180.203. Rather, we will modify the definition of the
test based on comments to indicate clearly that the test is to be
conducted with a liquid medium, unless otherwise authorized by a
special permit.

Section 180.207

    Section 180.207(d) authorizes the use of ISO 6406 to requalify UN
refillable seamless steel cylinders and UN refillable seamless steel
tube cylinders. The current ISO 6406 has a limitation of 150 liters for
the size of these cylinders, which is substantially less than the
maximum volume of a UN refillable seamless steel tube (3,000 liters).
Pressure tests and ultrasonic examination are authorized for UN
cylinders with tensile strength below 950 MPa, and only ultrasonic
examination is authorized for UN cylinders with a tensile strength
greater than or equal to 950 MPa. PHMSA has received several requests
for interpretation of this regulation and its application to the
requalification of UN seamless steel pressure receptacles larger than
150 liters. PHMSA responded to these requests through a letter of
clarification issued under Reference No. 13-0146, stating that Sec.
180.207(d)(1) authorizes the requalification of seamless steel UN
pressure receptacles larger than 150 liters.
    We received two comments on this topic. Bancroft Hinchey supports
the revision to include the phrase ``larger than 150 liters.'' FIBA
submitted a comment requesting that we delete the reference to MEGCs
from Sec.  180.207(d) because pressure receptacles exceeding 150 liters
(e.g. UN refillable seamless steel tubes) may be used for the
transportation of hazardous materials not only in MEGCs, but also in
other bulk packages, such as a tube trailer motor vehicle.
    PHMSA response. We agree with FIBA that UN seamless steel cylinders
larger than 150 liters may be found in other packaging configurations
besides MEGCs. Our intent is to clarify that all UN seamless steel
cylinders, regardless of size or service must be requalified in
accordance with ISO 6406. However, we believe there is value in
referencing MEGCs as an example of a scenario where users, fillers, or
requalifiers may encounter these larger UN cylinders. Therefore, in
this final rule we will amend the proposed Sec.  180.207(d)(1) to
indicate that all UN seamless steel pressure receptacles, including
those with a capacity over 150 liters, must be requalified in
accordance with ISO 6406 whether installed in a MEGC or used in other
service.

Section 180.213

    Section 180.213 prescribes marking requirements for the visual
inspection of cylinders (see 49 CFR 180.213(f)(5), (8), and (9)). In
the past, PHMSA has allowed a visual (V) requalifier identification
number (``V-number'' or ``VIN'') to be marked in the same manner as a
requalifier identification number (RIN) marking per Sec.  180.213. V-
number markings have four different options for markings. PHMSA issues
approval letters that permit a V number marking, but only provide for
three of the four available marking options and do not reference Sec.
180.213.
    Including all the marking requirements for V-numbers into Sec.
180.213 will make authorized options for these identification numbers
to be placed on a cylinder more widely understood.
    Amerigas noted that when we inserted examples of acceptable ways to
mark a VIN, we omitted one acceptable marking combination that is found
in the VIN approval document. Bancroft Hinchey submitted a comment
supporting inserting VIN marking examples into the HMR.
    PHMSA response. We agree with Amerigas, and will add the additional
method that shows the month and year directly above the VIN. In this
final rule, PHMSA is amending Sec.  180.213(g) to include examples of
V-number markings, as proposed, as well as the method showing the month
and year directly above the VIN.

Section 180.215

    Section 180.215(a)(6) requires that a person who requalifies,
repairs, or rebuilds cylinders must maintain in their records and
report information contained in each applicable CGA or ASTM standard
incorporated by reference under Sec.  171.7 of the HMR that applies to
requalifier activities. In the NPRM, PHMSA proposed to remove the last
sentence of paragraph (a)(6) of this section to reduce confusion, as it
essentially repeats what is requested in the first sentence of this
paragraph.
    We received one comment on this topic. Bancroft Hinchey submitted a
comment supporting this change. Therefore, in this final rule we will
adopt it as proposed. COSTHA submitted a comment requesting that PHMSA
revise the language in Sec.  180.215(c)(2)(vii) to delete the phrase
``(permanent expansion may not exceed ten percent (10 percent) of total

expansion)'' because this requirement does not apply to all cylinders.
We note the comment but consider it beyond the scope of this
rulemaking. We will consider the topic for possible inclusion in a
future rulemaking.

VII. Section-by-Section Review

Section 107.803

    Section 107.803(c)(3) states that each application to obtain
approval to perform duties as an IIA must contain a detailed
description of the applicant's qualifications and ability both to
perform the inspections and to verify the inspections required by part
178 of the HMR or under the terms of a DOT special permit. In this
final rule, we revise Sec.  107.803(c)(3) as proposed to clarify that
the applicant's description of his or her ability to perform and verify
inspections must include those required under part 180 as well,
consistent with the general requirements in paragraph (a) that refer to
part 180.

Section 107.805

    Section 107.805(c) prescribes additional information an application
must contain to obtain approval from PHMSA to requalify cylinders and
pressure receptacles. In this final rule, we are adding paragraph
(c)(5) as proposed to this section to clarify what information must be
added to the application to authorize mobile unit requalifiers and the
information necessary to acquire approval. We also make a conforming
edit to paragraphs (c)(3) and (4) by moving the ``and'' clause from
paragraph (c)(3) to paragraph (c)(4).

Section 171.7

    Section 171.7 lists reference standards incorporated by reference
into the HMR that are not specifically set forth in the HMR.
    Paragraph (n) specifically incorporates into the HMR publications
issued by the CGA, an industrial and medical gas association that,
among others, develops standards and practices for the safe
transportation of gases and their containers. In this final rule, we
add the Eleventh edition (2016) of CGA publication C-1, Methods for
Pressure Testing Compressed Gas Cylinders to Sec.  171.7(n). We also
update the editions of CGA publications C-3, C-6, C-14, and S-1.1
already incorporated in the HMR. The remaining changes to paragraph (n)
are editorial based on PHMSA's initiative to renumber the list to
accommodate the new publications and add missing section number
symbols, punctuation, and spaces. The documents are summarized below.
    The CGA publications include the following:
    (1) CGA C-1, Methods for Pressure Testing Compressed Gas Cylinders
(2016; Eleventh edition). This publication provides the standard(s) for
pressure testing of compressed gas cylinders for many newly
manufactured cylinders and requalification of cylinders. This standard
contains operating and equipment requirements necessary to perform
pressure testing of compressed gas cylinders properly. Tests include
the water jacket method, direct expansion method, and proof pressure
method.
    (2) CGA C-3, Standards for Welding on Thin-Walled Steel Cylinders
(2005, Reaffirmed 2011; Seventh edition). This publication contains
information on welding process qualification, welding operator
qualifications, tensile testing, bend testing, and radiographic
inspection. Additionally, this publication clarifies dimensional
tolerances and when weld macro etch can be used for weld process
approval and welder qualification approval.
    (3) CGA C-6, Standards for Visual Inspection of Steel Compressed
Gas Cylinders (2013; Eleventh edition). This publication provides
cylinder users (requalifiers, owners, fillers, operators, etc.) with
criteria to accept, reject, and condemn steel compressed gas cylinders.
This standard does not cover all circumstances for each individual
cylinder type and condition of lading. Inspection procedures include
preparation of cylinders for inspection; exterior inspection; interior
inspection (if required); nature and extent of damage to be looked for;
and for some tests, the conditions of the cylinder, etc. A sample
inspection report is provided in an appendix.
    (4) CGA C-14, Procedures for Fire Testing of DOT Cylinder Pressure
Relief Device Systems (2005, Reaffirmed 2010; Fourth edition). This
publication describes test procedures and apparatus for fire testing
compressed gas cylinder safety (pressure) relief devices as required by
the HMR. The procedures are applicable for cylinders that have less
than 500 lbs. water capacity and designed to provide a means of testing
to the HMR anywhere with reliable test data and repeatable test
results.
    (5) CGA S-1.1, Pressure Relief Device Standards--Part 1--Cylinders
for Compressed Gases (2011; Fourteenth edition). This publication
provides the standard(s) for selection of the correct pressure relief
device that is required to meet the requirements of the HMR for over
150 gases. It provides guidance on when a pressure relief device can be
optionally omitted, and when the use of a pressure relief device is
prohibited. It provides direction and guidance on the manufacture and
testing of pressure relief devices as well as the operation parameters
and maintenance. In this final rule, we are removing the phrase ``with
the exception of paragraph 9.1.1'' from Sec.  171.7(n)(18). Compliance
with paragraph 9.1.1 is still not required; however, we have moved this
instruction to each place S-1.1 is incorporated in Part 173 and Part
178 for clarity.
    All of these CGA standards are available for purchase on the CGA
website.\11\ Additionally, these standards are available for public
inspection at the Hazardous Material Information Center ((202) 366-
4488<EMAIL_ADDRESS>by appointment.
---------------------------------------------------------------------------

    \11\ https://www.cganet.com/what-we-do/standards-publications/.
---------------------------------------------------------------------------

    The regulatory text of this rule references ASTM E 8-99, The
Aluminum Association's ``Welding Aluminum: Theory and Practice, Fourth
Edition, 2002'', and Transport Canada's TDG Regulations. These
standards are already approved for the sections that are being amended.

Section 171.23

    Section 171.23 prescribes requirements for transport of specific
materials and packaging under international transportation standards
such as the International Civil Aviation Organization Technical
Instructions for the Safe Transport of Dangerous Goods by Air.
Paragraph (a)(5) outlines requirements for filling of cylinders for
export or use onboard a vessel. In this final rule, we revise the
marking requirements consistent with changes made to Sec.  180.213.

Section 173.3

    Section 173.3(d)(1) prescribes how a damaged or leaking cylinder
that contains hazardous material may be transported in a non-DOT-
specification fully opening hinged-head or removable head steel salvage
cylinder. In this final rule, we are amending Sec.  173.3(d)(1) to
permit cylinders that contain Class 4 or 5 materials to use this
exception as well. In addition, because of the inclusion of Class 4 or
5 materials as authorized material for salvage cylinders, we are
reformatting the regulatory text to reference those materials in
damaged or leaked cylinders that are excluded from being allowed to be
overpacked in a salvage cylinder rather than listing those that are
authorized.

Section 173.301

    Section 173.301 provides the general requirements for shipment of
compressed gases and other hazardous material in cylinders. In this
final rule in paragraphs (c) and (f), we make an editorial revision to
correct the section citation of CGA S-1.1 to read 9.1.1. Additionally,
we are revising paragraph (f) to clarify the pressure relief
requirements for DOT 39 cylinders. See the discussion of P-1580 for
further details.

Section 173.302

    Section 173.302(f) prescribes the requirements for transporting
non-liquefied or ``permanent'' oxidizing gases by air. We are amending
Sec.  173.302(f)(2)(i) and adding a new Sec.  173.302(f)(2)(iii) to
align with CGA S-1.1 requirements for DOT 39 cylinders. See the
discussion of P-1580 for further details.

Section 173.302a

    Section 173.302a(a)(3) prescribes the filling requirements for DOT
39 cylinders that contain Division 2.1 gas or chemical under pressure.
In the NPRM, we proposed to clarify the capacity (internal volume)
requirements, to make it clear that the 1.23 liter limit applies to
Division 2.1 material, and specification size limits of a DOT 39
cylinder apply to chemicals under pressure classed as Division 2.1 (see
49 CFR 172.102, special provision 362). As we noted in the NPRM, the
previous 50 L limit for chemical under pressure in a DOT 39 cylinder is
much larger than the actual maximum size authorized for the DOT 39
specification in Sec.  178.65. This discrepancy was an unintentional
outcome of a harmonization effort with international requirements for
non-refillable cylinders, which allow larger sizes than the HMR (see
Docket No. PHMSA-2012-0027 (HM-215L); 78 FR 988). To reduce confusion
introduced by the conflict of the 50 L quantity in Sec.  173.302a(a)(3)
and the capacity limts of the specification, we are deleting the
reference to ``50 L (3050 in\3\)'' and replacing it with reference to
the DOT 39 specification capacity limits--1526 in\3\ for a service
pressure of 500 psig or less, and 277 in\3\ for a service pressure of
greater than 500 psig.
    We also proposed an editorial correction to the start of paragraph
(a)(3) by removing the non-italicized ``DOT 39.''
    Section 173.302a(c) provides special filling limits for DOT 3A,
3AX, 3AA, and 3AAX cylinders filled with hydrogen and mixtures of
hydrogen with helium, argon, or nitrogen. We are modifying Sec.
173.302a(c)(4) to harmonize with CGA S-1.1. Shippers are not required
to install pressure relief devices on tubes (cylinders longer than 144
inches, or 12 feet) shipped in accordance with this paragraph, however
their continued use and installation is authorized. This change
maintains regulatory flexibility and alignment with accepted industry
practice. See discussion of P-1592 for further details.

Section 173.304

    Section 173.304(f) prescribes the requirements for transporting
liquefied compressed oxidizing gases by air. In this final rule, we are
amending Sec.  173.304(f)(2)(i) and adding a new Sec.
173.304(f)(2)(iii) to align with CGA S-1.1 pressure relieve device
requirements for DOT 39 cylinders. See the discussion of P-1580 for
further details.

Section 173.304a

    Section 173.304a prescribes the maximum permitted filling density
and authorized cylinders for specific gases. In the NPRM, we proposed
to add new paragraph (a)(3) to Sec.  173.304a to state clearly that the
maximum capacity (internal volume) of a DOT 39 cylinder containing
liquefied flammable gas is 1.23 liters (75 in\3\). We also proposed to
require these cylinders to be equipped with a pressure relief valve, as
prescribed in CGA S-1.1, unless the material is not listed in CGA S-
1.1, in which case a CG-7 pressure relief valve must be used.
    In this final rule we are modifying our proposed change to Sec.
173.304a and imposing a 75 in\3\ limit on the capacity of DOT 39
cylinders containing the following liquefied flammable gases:
Cyclopropane, ethane, ethylene, and liquefied petroleum gas. We are
also adopting the requirement that a DOT 39 cylinder containing a
liquefied gas not listed by name in CGA S-1.1 must be equipped with a
CG-7 pressure relief valve, as proposed. See discussion of P-1622 for
further details.

Section 173.306

    Section 173.306 provides exceptions from the requirements of the
HMR for limited quantities of compressed gas. Paragraph (g) excepts
water pump system tanks charged with compressed air or limited
quantities of nitrogen to not over 40 psig from labeling and
specification packaging when shipped in conformance with the
requirements prescribed in the paragraph. In this final rule, we revise
Sec.  173.306(g) to authorize composite as well as steel tanks, to
require a more flexible testing regime at the manufacturers MAWP rather
than a set 100 psig, to allow water pump system tanks to be charged
with helium, and to clarify that transportation by aircraft is not an
authorized mode of transport. See discussion of P-1582 for more
details.

Section 173.309

    In the NPRM, we proposed to revise Sec.  173.309 to state that the
requirements applicable to fire extinguishers also apply to those
cylinders used as part of a fire suppression system. In this final
rule, we are adopting the change as proposed, while clarifying our
intent as to what is considered a ``fire extinguisher.'' We are
allowing cylinders charged with a compressed gas and an extinguishing
agent that are intended for installation into fire suppression systems
to be described as ``UN1044, Fire extinguishers.'' We are not allowing
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.
See discussion of P-1546 for further details.

Section 173.312

    Section 173.312(b)(1) prescribes the filling requirements for
multiple element gas containers (MEGCs). In this this final rule, we
are clarifying requirements for filling MEGC pressure receptacles
containing liquefied compressed gas by weight to emphasize that each
pressure receptacle must be filled individually. See discussion of P-
1572 for further details.

Section 173.323

    Section 173.323 is the packaging section for ethylene oxide. In
this final rule, we are making an editorial revision to this section to
add a reference to the central IBR section, Sec.  171.7, for the
existing references to CGA Pamphlet C-14. CGA C-14 was previously
approved for inclusion in this section, but through an oversight, Sec.
171.7 was not referenced as required for approved IBRs. This final rule
corrects that oversight.

Section 178.35

    Section 178.35(f) prescribes the marking requirements that apply to
DOT-specification cylinders. In this final rule, we are adding new
paragraph (f)(8) to Sec.  178.35 to require that cylinder tare weight
or mass weight, and water capacity be marked on certain DOT-
specification cylinders that are filled by weight. See discussion of P-
1540 for further details.
    Although we did not discuss the above in the petition discussion
section,

we note Dow Chemical submitted a comment requesting that we add a
paragraph to Sec.  178.35 stating that a cylinder manufactured under
this subpart prior to publication of HM-234 may continue to be filled
and offered for transportation until its authorized service life has
expired. We do not believe such a statement is necessary. Section
173.301(a)(1) addresses this situation by providing that compressed
gases must be in UN pressure receptacles built in accordance with the
UN standards or in metal cylinders and containers built in accordance
with the DOT and ICC specifications and part 178 in effect at the time
of manufacture or CRC, BTC, CTC or TC specification, and requalified
and marked as prescribed in subpart C in part 180, if applicable.
    Cylinders manufactured prior to the publication of HM-234 may
continue in service, subject to the requalification provisions of part
180, subpart C, and other applicable requirements of the subchapter.

Sections 178.36, 178.37, 178.38, 178.39, 178.42, 178.44, 178.45,
178.46, 178.47, 178.50, 178.51, 178.53, 178.55 178.56, 178.57, 178.58,
178.59, 178.60, 178.61, 178.65, and 178.68

    These sections prescribe the DOT-specification requirements for a
cylinder type including the performance standards for pressure testing
of the cylinder. In this final rule, we require that testing and
equipment used to conduct the pressure testing be in conformance with
CGA C-1, Methods for Pressure Testing Compressed Gas Cylinders, to
provide for consistency and clarity in performance of pressure testing.
In this final rule, we also revise the format of the pressure testing
paragraphs for greater consistency, including adding notification that
any pressurization in excess of 90% of test pressure constitutes a
test, and that operator error (i.e. selecting the wrong test pressure)
is an acceptable reason to allow a repeated test in accordance with CGA
C-1 requirements. See the discussions of P-1515 and P-1626 for further
details on the requirements in CGA C-1. A detailed discussion of
changes to each section follows.

Section 178.36 Specification 3A and 3AX Seamless Steel Cylinders

    The paragraph (i) title ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into (i)(1) and (3)
for volumetric expansion testing as proposed.

Section 178.37 Specification 3AA and 3AAX Seamless Steel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(i)(1) and (3) for volumetric expansion testing as proposed.

Section 178.38 Specification 3B Seamless Steel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(i)(1) and (3) for volumetric expansion testing as proposed. To
increase clarity, in this final rule we move the instructions for proof
pressure testing of cylinders after a selected cylinder from a lot is
volumetrically expansion tested at 3 times service pressure from the
proposed paragraph (i)(5) to paragraph (i)(2)(ii) to ensure cylinder
manufactures are aware of the requirement when reading through
paragraph (i). As a result, we also incorporate CGA C-1 into paragraph
(i)(2) for proof pressure testing.

Section 178.39 Specification 3BN Seamless Nickel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(i)(1) and (3) as proposed.

Section 178.42 Specification 3E Seamless Steel Cylinders

    The paragraph (f) ``Hydrostatic test'' is renamed ``Pressure
testing'' as proposed. As discussed in our discussion of P-1626 we are
not adopting the proposed re-organization of Sec.  178.42(f) based on
comments received that the new layout would generate confusion for
regulated entities. Further, CGA C-1 is incorporated by reference for
burst testing in paragraph (f)(2) and proof pressure testing in
paragraph (f)(3).

Section 178.44 Specification 3HT Seamless Steel Cylinders for Aircraft
Use

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(i)(1) and (3) for volumetric expansion testing as proposed.

Section 178.45 Specification 3T Seamless Steel Cylinder

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(i)(1) and (3) for volumetric expansion testing as proposed.

Section 178.46 Specification 3AL Seamless Aluminum Cylinders

    The paragraph (g) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(g)(1) and (3) for volumetric expansion testing as proposed. The HMR
currently only allows one repeat test for 3AL cylinders in the case of
equipment failure. As proposed, we maintain this requirement in this
final rule. 3AL cylinders may only be subjected to one repeat test,
rather than the two allowed under CGA C-1. This is due to the different
expansion properties of aluminum compared to steel, which would render
the expansion measured during a 2nd repeated test at increased pressure
an invalid measurement of the cylinder's suitability.

Section 178.47 Specification 4DS Welded Stainless Steel Cylinders for
Aircraft Use

    The paragraph (j) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference into paragraphs
(j)(1) and (3) for volumetric expansion testing as proposed. As
proposed, the final rule adds an option for direct expansion testing
for 4DS cylinders. PHMSA believes that including the hydrostatic
testing direct expansion method in addition to the water jacket method
provides for greater flexibility for the tester by allowing an
alternative hydrostatic testing method for determining permanent
expansion. PHMSA believes that direct expansion will provide an
equivalent level of safety when performed in accordance with CGA C-1.

Section 178.50 Specification 4B Welded or Brazed Steel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (i)(1)
for volumetric expansion testing of one selected cylinder per lot, and
(i)(2) for pressure testing the remainder of the lot as proposed.

Section 178.51 Specification 4BA Welded or Brazed Steel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (i)(1)
for volumetric expansion testing of one selected cylinder per lot, and
paragraph (i)(2) for pressure testing the remainder of the lot as
proposed.

Section 178.53 Specification 4D Welded Steel Cylinders for Aircraft Use

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure test''
and CGA C-1 is incorporated by reference as proposed. In this final
rule, we are re-inserting the option to conduct a volumetric expansion
test on each cylinder at 2 times service pressure. It was not our
intent to remove this option for cylinder manufacturers.

Section 178.55 Specification 4B240ET Welded or Brazed Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (i)(1)
for volumetric expansion testing, paragraph (i)(2) for pressure
testing, and paragraph (i)(3) for burst testing as proposed.

Section 178.56 Specification 4AA480 Welded Steel Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (i)(1)
for volumetric expansion testing and paragraph (i)(2) for pressure
testing as proposed.

Section 178.57 Specification 4L Welded Insulated Cylinders

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraphs (i)(1)
and (3) for pressure testing as proposed.

Section 178.58 Specification 4DA Welded Steel Cylinders for Aircraft
Use

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraphs (i)(1)
and (3) for volumetric expansion testing as proposed.

Section 178.59 Specification 8 Steel Cylinders With Porous Fillings for
Acetylene

    The paragraph (h) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated in paragraph (h)(1) for
volumetric expansion testing and paragraph (h)(2) for pressure testing
as proposed. Additionally, we have editorially revised paragraph (h) to
clarify that if the randomly selected cylinder from each lot fails the
volumetric expansion test, the remaining cylinders in the lot are not
eligible for proof pressure testing and each cylinder must pass a
volumetric expansion test at 750 psig to be accepted.

Section 178.60 Specification 8AL Steel Cylinders With Porous Fillings
for Acetylene

    The paragraph (j) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (j)(1)
for volumetric expansion testing and paragraph (j)(2) for proof
pressure testing as proposed. Additionally, we have editorially revised
paragraph (j) to clarify that if the randomly selected cylinder from
each lot fails the volumetric expansion test, the remaining cylinders
in the lot are not eligible for proof pressure testing and must pass a
volumetric expansion test at 750 psig to be accepted.

Section 178.61 Specification 4BW Welded Steel Cylinders With Electric-
Arc Welded Longitudinal Seam

    The paragraph (i) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (i)(1)
for volumetric expansion testing and paragraph (i)(2) for pressure
testing as proposed.

Section 178.65 Specification 39 Non-Reusable (Non-Refillable) Cylinders

    The paragraph (f) ``Pressure tests'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraph (f)(1)
for proof pressure testing and paragraph (f)(2) for burst testing as
proposed.

Section 178.68 Specification 4E Welded Aluminum Cylinders

    The paragraph (h) ``Hydrostatic test'' is renamed ``Pressure
testing'' and CGA C-1 is incorporated by reference in paragraphs (h)(1)
and (2) for volumetric expansion testing and paragraph (h)(3) for
pressure testing as proposed.

Sections 178.50, 178.51, 178.61, and 178.68

    These sections prescribe DOT 4-series specification requirements.
As written these specifications are at times unclear to manufacturers
and enforcement personnel. In this final rule, we are revising the
specification requirements to promote consistent and uniform
manufacturing practices for DOT 4-series cylinders to improve
understanding by these entities. See the discussion of P-1501 for
further details. Below we will discuss changes to each section in
detail.

Section 178.50 Specification 4B Welded or Brazed Steel Cylinders

    For steel requirements, we are requiring that manufacturers keep a
record of intentionally added alloying elements, as proposed.
    For material identification, the final rule makes an editorial
clarification that the method used to identify the material must not
compromise the integrity of the cylinder, as proposed.
    For heat treatment, we are making an editorial clarification to
direct cylinder manufacturers to table 1 to appendix A of part 178 for
details on suitable heat treatment.
    For cylinder attachments, we have moved thread requirements to
their own paragraph, (h)(h), without making any changes to thread
requirements.
    For elongation requirements, we are allowing reduction in
elongation percentage based on cylinder tensile strength to align with
requirements for DOT 4BA and 4BW cylinder requirements.
    For rejected cylinders, we are adopting as proposed heat treatment
after seam repairs requirements as follows:
     For cylinders with an outside diameter of less than or
equal to six (6) inches, welded seam repairs greater than one (1) inch
in length shall require reheat treatment of the cylinder.
     For cylinders greater than an outside diameter of 6
inches, welded seam repairs greater than three (3) inches in length
shall require reheat treatment.
    The HMR current manufacturing standards require heat treatment
after any welding repair, but we believe this additional flexibility
for manufacturers will maintain the same high level of safety for
repaired cylinders.
    Finally, we are removing discussion of embossing the head or
sidewall of the cylinder from Sec.  178.50(o)(2). PHMSA has concerns
with defining ``embossing.'' Markings must be stamped plainly and
permanently on the cylinder as prescribed in Sec.  178.50(o)(1).

Section 178.51 Specification 4BA Welded or Brazed Steel Cylinders

    For steel, we are requiring that manufacturers keep a record of
intentionally added alloying elements, as proposed.
    For material identification, the final rule makes an editorial
clarification that the method used to identify the material must not
compromise the integrity of the cylinder, as proposed.
    For head attachment, we are allowing heads to be attached by
welding, as proposed. The previous restriction to brazing only was not
PHMSA's intent.
    For seams, we are making an editorial revision to paragraph (a) to
clarify that longitudinal seams are permitted for cylindrical-type
cylinders as proposed.

    For welding, we are making an editorial revision to paragraph (e),
as proposed, to clarify allowable welding operations on the cylinder.
    For yield strengths, tensile strengths, elongations and reduction
of area of material, we are re-naming paragraph (j) from ``Physical
tests'' to ``Mechanical tests'' as proposed. Additionally, we are
removing the language requiring that the mechanical tests be conducted
on a cylinder that has passed the hydrostatic testing because the
mechanical tests are unrelated to the pressure test requirements.
During our review of the final rule, we noted we inadvertently omitted
the requirement that mechanical tests must be conducted after heat
treatment. This was not our intent; therefore, we are re-inserting the
statement that mechanical tests must be conducted after heat treatment
is performed.
    For mechanical test samples for spherical cylinders, we are now
allowing samples to be taken directly from the formed sphere, if the
manufacturer desires, in order ensure the mechanical test samples are
as representative as possible of the spheres themselves.
    In this final rule, we require that manufacturers remove samples
for mechanical tests as provided in appendix A to subpart C of part 178
as proposed in order to improve consistency of cylinder mechanical
tests. PHMSA believes that all manufacturers were previously removing
samples as recommended in appendix A to subpart C of part 178,
therefore this will not create any new burdens for industry.
    For rejected cylinders, we are adopting as proposed heat treatment
after seam repairs requirements as follows:
     For cylinders with an outside diameter of less than or
equal to six (6) inches, welded seam repairs greater than one (1) inch
in length shall require reheat treatment of the cylinder.
     For cylinders greater than an outside diameter of 6
inches, welded seam repairs greater than three (3) inches in length
shall require reheat treatment.

The HMR current manufacturing standards require heat treatment after
any welding repair, but we believe this additional flexibility for
manufacturers will maintain the same high level of safety for repaired
cylinders.
    Finally, we are removing discussion of embossing the head or
sidewall of the cylinder from Sec.  178.51(n)(2). PHMSA has concerns
with defining ``embossing.'' Markings must be stamped plainly and
permanently on the cylinder as prescribed in Sec.  178.51(n)(1).

Section 178.61 Specification 4BW Welded Steel Cylinders With Electric-
Arc Welded Longitudinal Seam

    For steel, we are requiring that manufacturers keep a record of
intentionally added alloying elements, as proposed.
    For identification of material, the final rule makes an editorial
clarification that the method used to identify the material must not
compromise the integrity of the cylinder, and that plates and billets
for hotdrawn cylinders must be marked with the heat number, as
proposed. PHMSA believes that cylinder manufacturers are already in
compliance with this requirement and this does not impose any new
burden on industry.
    For examination of welds, we are adding reference to radioscopic
examination, when conducted in accordance with CGA C-3, to increase
flexibility for manufacturers while not compromising examination of
welds.
    For heat treatment, we are aligning the heat treatment requirements
with those for DOT 4BA cylinders and clarifying that heat treatment may
occur before, during, or after brazing operations.
    For yield strengths, tensile strengths, elongations and reduction
of area of material, we are re-naming paragraph (j) from ``Physical
tests'' to ``Mechanical tests'' and adding introductory text as
proposed. This editorial change is intended to align the 4BW
specification language with the similar DOT 4B and 4BA cylinders
language. Additionally, we are requiring that manufacturers remove
samples for mechanical tests as provided in appendix A to subpart C of
part 178, as proposed, in order to improve consistency of cylinder
mechanical tests. PHMSA believes that all manufacturers were previously
removing samples as recommended in appendix A to subpart C of part 178,
therefore this will not create any new burdens for industry. Finally,
for the guided bend test we are aligning the DOT 4BW requirements with
the 4BA and allowing specimens to be taken from welded test plates and
additional specimen testing if the original specimen fails.
    For openings to cylinders, we are aligning the DOT 4BW requirements
with the existing requirements for DOT 4B and 4BA cylinders as proposed
to promote consistency and simplify compliance for manufacturers
producing these similar cylinders. Additionally, we are aligning the
4BW with the 4B specification by adding an allowance to attach brass
fittings that are components of handheld fire extinguishers.
    For rejected cylinders, we are adopting as proposed heat treatment
after seam repairs requirements as follows:
     For cylinders with an outside diameter of less than or
equal to six (6) inches, welded seam repairs greater than one (1) inch
in length shall require reheat treatment of the cylinder.
     For cylinders greater than an outside diameter of 6
inches, welded seam repairs greater than three (3) inches in length
shall require reheat treatment.
    The HMR current manufacturing standards require heat treatment
after any welding repair, but we believe this additional flexibility
for manufacturers will maintain the same high level of safety for
repaired cylinders.
    For marking, we are adding the following marking locations:
    1. On side wall adjacent to top head for side walls not less than
0.090 inch thick.
    2. On a cylindrical portion of the shell that extends beyond the
recessed bottom of the cylinder constituting an integral and non-
pressure part of the cylinder.
    3. Neckring.

These new locations for the 4BW are already allowed for the very
similar 4BA cylinder, are intended to align the 4BW with the 4BA with
no decrease in safety.

    Finally, we are removing discussion of embossing the head or
sidewall of the cylinder from Sec.  178.61(n)(2). PHMSA has concerns
with defining ``embossing.'' Markings must be stamped plainly and
permanently on the cylinder as prescribed in Sec.  178.61(n)(1).

Section 178.68 Specification 4E Welded Aluminum Cylinders

    For aluminum material in Sec.  178.68(b), we are requiring that
manufacturers keep a record of intentionally added alloying elements,
as proposed. Additionally, we are revising Note 1 to Table 1 to
maintain the requirement to conduct regular analysis of the material.
It was our intent for the requirement to record intentionally added
alloying elements to complement the regular analysis of the material,
not replace it.
    For yield strengths, tensile strengths, elongations and reduction
of area of material, we are re-naming paragraph (j) from ``Physical
tests'' to ``Mechanical tests'' as proposed. For acceptable results for
mechanical tests we are not adding the phrase ``a minimum tensile
strength as defined in paragraph (f)(1)(ii)

of this section'' to paragraph (k). This text is unnecessary, therefore
we are not adopting it. For the alternate guided bend test, we are
revising requirements to align with the standards of the Aluminum
Association and similar low-pressure steel cylinders.
    Finally, we are removing discussion of embossing the head or
sidewall of the cylinder from Sec.  178.68(n)(2). PHMSA has concerns
with defining ``embossing.'' Markings must be stamped plainly and
permanently on the cylinder as prescribed in Sec.  178.68(n)(1).

Section 178.70

    Section 178.70(d) prescribes the requirements to obtain design
approval of a UN pressure receptacle. In this final rule, we are
revising paragraph (d) as proposed to include language that an approval
for a design modification is not required if the specific design
modification is covered under the UN/ISO standard for the design type
already approved.
    In our review of the NPRM, we discovered we inadvertently deleted
the sentence ``An audit may be required as part of the process to
modify an approval'' from Sec.  178.70(d). This was not our intent,
therefore in this final rule we are reinserting this sentence.

Section 178.75

    Section 178.75 contains the requirements for construction of Multi-
Element Gas Containers (MEGCs). In this final rule, we are making two
editorial revisions to Sec.  178.75. First, we are correcting a spacing
error that made paragraphs (e)(3)(i) and (ii) appear to be part of the
same paragraph. Additionally, we are clarifying that compliance with
CGA S-1.1 paragraph 9.1.1 is not required for PRDs installed on MEGCs.
This editorial change is necessary because we have removed the phrase
``except 9.1.1'' from the central Sec.  171.7 IBR reference for CGA S-
1.1.

Section 180.203

    Section 180.203 prescribes definitions that apply to the
qualification, maintenance, and use of cylinders under the HMR. In this
final rule, we add new definitions for the terms or phrases ``mobile
unit'' and ``over-pressurized,'' and revise the definitions for
``commercially free of corrosive components'' and ``proof pressure
test.'' We previously discussed the definitions for ``mobile unit'' and
``proof pressure test'' in Section VII. Agency Initiated Editorial
Corrections. The revision to ``commerically free of corrosive
components'' is an editorial revision to express the allowable water
content in parts per million (ppm) rather than dew point. We added a
definition for ``over-pressurized'' because it is now included as a
condition for condemnation of a cylinder under Sec.  180.205(i)--i.e.,
a cylinder that is known to have been or shows evidence of being
``over-pressurized.'' We received no comments related to the new
definition for ``over-pressurized'' and therefore will adopt as
proposed. We delete the definitions for ``defect,'' ``elastic
expansion,'' ``permanent expansion,'' ``rejected cylinder,'' ``test
pressure,'' ``total expansion,'' ``visual inspection,'' and
``volumetric expansion test.'' These new and revised definitions will
clarify the cylinder requirements prescribed in part 180, subpart C.
The deletion of definitions is intended to remove conflicts and
redundancies with the newly incorporated by reference CGA C-1
definitions. See discussion of P-1515 and P-1626 for further discussion
of CGA C-1.

Section 180.205

    Section 180.205 prescribes the general requirements for
requalifying DOT-specification cylinders. In this final rule, we are
revising and adding new regulatory text for clarity, and incorporating
CGA C-1 into the HMR. Specifically, we clarify the conditions requiring
test and inspection of cylinders under paragraph (d) by including a
reference to thermal damage as proposed by P-1515 (discussed above in
Section IV) to identify cylinders weakened by exposure to heat and
evidence of grinding; revise the paragraph (f) visual inspection
requirements to include reference to shot blasting and ``chasing'' of
cylinders as proposed by P-1515 in accordance with previous PHMSA
guidance; revise the paragraph (g) requirements for pressure tests by
incorporating by reference CGA C-1; editorially revise paragraph (h) to
clarify that rejected cylinders must be repaired or rebuilt as provided
in Sec.  180.211 prior to further use, not just requalified; revise
paragraph (i) to clarify the responsibilities of the requalifier and
add conditions under which a cylinder must be condemned, including arc
burns on aluminium cylinders, known over-pressurization, end of service
life, and stamping on sidewalls as proposed by P-1515; and move the
reference of training materials to its own paragraph (j). See
discussion of P-1515 and P-1626 for additional information on the
incorporation of CGA C-1.

Section 180.207

    Section 180.207 prescribes requirements for requalifying UN
pressure receptacles. In this final rule, we revise and add new
regulatory text for clarity. In the NPRM, we proposed to remove
language authorizing approvals for the extension of the service life of
a composite ISO pressure receptacle and require condemnation in
accordance with Sec.  180.205(i)(1)(x). In this final rule, we will not
adopt these changes, but we will remove reference to a 15-year service
life because it does not apply to all ISO composite cylinders. Approval
may still be sought to extend the life of ISO composite pressure
receptacles and each request will be considered on a case by case
basis. Additionally, we clarify language in the introduction to the
requalification table to confirm that UN pressure receptacles must be
requalified prior to filling the cylinders beyond the marked
requalification date; editorially revise paragraph (d) for clarity; and
revise the requalification procedures for seamless steel cylinders to
include MEGC and other pressure receptacles larger than 150 liters
water capacity.

Section 180.209

    Section 180.209 prescribes requirements for requalifying
specification cylinders. In this final rule, we are revising and adding
new regulatory text for clarity and incorporating by reference the 2016
version of CGA C-1, Methods for Pressure Testing Compressed Gas
Cylinders. Specifically, we revise: The requirement for a hammer test
in Sec.  180.209(b); the paragraph (c) tare weight marking
requirements; the paragraph (e) proof pressure testing requirements to
incorporate by reference CGA C-1; the paragraph (g) visual inspection
requirements to remove the obsolete reference to a delayed compliance
period that ended in 2004 and to create an entry for cylinders
containing propylene, commercially free from corroding components to be
requalified visually as proposed by P-1626; the paragraph (j)
requirements for fire extinguisher requalification to align with CGA C-
1, including allowing direct expansion tests for 4-series cylinders
used as fire extinguishers because we believe the direct expansion
method is an equivalent method for requalifying fire extinguishers; and
the paragraph (l) requirements for marking foreign cylinders. See
discussion of P-1626 and P-1515 for additional information on the
incorporation of CGA C-1 and additional editorial revisions to Sec.
180.209.

Section 180.212

    Section 180.212(a) prescribes requirements to repair seamless DOT
3-

series specification cylinders and seamless UN pressure receptacles. In
this final rule, we are revising paragraph (a) to require an ultrasonic
examination on DOT 3-series cylinders and seamless UN pressure
receptacles after any grinding is performed on these cylinders.
Additionally, we are adopting as proposed prohibitions from removing
arc burns from cylinders. The presence of arc burns requires cylinder
rejection at time of visual inspection, and repair facilities may not
remove this evidence from a cylinder. We are adopting ultrasonic
examination requirements when grinding is conducted, as proposed. It is
PHMSA's understanding that cylinder repair facilities already regularly
conduct ultrasonic examination whenever wall thickness is removed or in
question, therefore this requirement should not impose any additional
burden on cylinder repairers. Finally, we are adopting as proposed a
new marking requirement for repaired cylinders to indicate compliance
with the repair requirements.

Section 180.213

    Section 180.213 prescribes requirements for marking DOT-
specification cylinders and UN pressure receptacles that are
successfully requalified. In this final rule, we also clarify the
marking requirements for foreign cylinders filled for export under
paragraph (d). The final rule includes two new marking requirements
under paragraph (f):
     Designation of grinding with ultrasonic wall thickness
examination; and
     designation of requalification of a foreign cylinder for
export only requalified in conformance with Sec. Sec.  171.23(a)(5) and
180.209(l) of the HMR. The ``EX'' marking for foreign cylinders
requalified for export only should not be confused with explosive
approvals numbers.
    Finally, we add visual inspection identifier number marking
requirements under a new paragraph (g) that codify the requirements
already found in visual requalifier approval documents.

Section 180.215

    Section 180.215 prescribes reporting and retention requirements for
a person who requalifies, repairs, or rebuilds cylinders. In this final
rule, we revise what information these documents must contain: For
calibration certificates, requalifiers must now retain a copy of the
most recent calibration certificate for their pressure indicating
device and expansion indicating device, to align with CGA C-1
requirements incorporated by reference under this final rule;
correcting an ambiguity in Sec.  180.215(c)(2)(vii) to clarify that
records for both proof pressure and volumetric expansion tests after
re-building a 4-series cylinder must be preserved; and for DOT 3-series
cylinders repaired using grinding, a record of the performance of
grinding repairs and ultrasonic examination.

VIII. Regulatory Analyses and Notices

A. Statutory/Legal Authority for This Final Rule

    This rulemaking responds to 20 petitions for rulemaking, one
special permit, and several agency-identified issues that have a
potential effect on hazardous materials transportation safety. Federal
Hazardous Materials Transportation Law (49 U.S.C. 5101-5128) authorizes
the Secretary of Transportation to ``prescribe regulations for the safe
transportation, including security, of hazardous material in
intrastate, interstate, and foreign commerce.'' The Secretary's
authority is delegated to PHMSA at 49 CFR 1.97.

B. Executive Order 12866 and DOT Policies and Procedures for
Rulemakings

    This final rule is not considered a significant regulatory action
under section 3(f) of Executive Order (E.O.) 12866, ``Regulatory
Planning and Review,'' 58 FR 51735, and was not reviewed by the Office
of Management and Budget (OMB). This rule is also not significant under
the Department of Transportation's Policies and Procedures for
Rulemakings (DOT Order 2100.6; Dec. 20, 2018).
    E.O. 12866 requires agencies to design regulations ``in the most
cost-effective manner,'' to make a ``reasoned determination that the
benefits of the intended regulation justify its costs,'' and to develop
regulations that ``impose the least burden on society.'' In this final
rule, PHMSA accomplishes the directives of E.O. 12866 by involving the
public and exercising its own independent judgment in responding to 20
petitions for rulemaking submitted by stakeholders in the compressed
gas industry. The final rule clarifies the regulatory text in the HMR
and incorporates widely used consensus standards to addresses specific
safety concerns, thus enhancing the safe transportation of compressed
gases while limiting the impact on the regulated community.
Additionally, some of the provisions will provide shippers and carriers
with additional flexibility to comply with established safety
requirements, thereby reducing burdens and costs and increasing
productivity.
    Overall, the issues discussed in this final rule promote the
continued safe transportation of hazardous materials while producing
net cost savings. PHMSA estimates the net cost savings associated with
this rule is approximately $70,000 per year, at a 7 percent discount
rate, over a ten-year analysis period from 2019 to 2028. Details on the
estimated cost savings of this final rule can be found in the rule's
economic analysis, which is available in the public docket.

C. Executive Order 13771

    This final rule is considered a deregulatory action under E.O.
13771. Details on the estimated cost savings of this final rule can be
found in the rule's Regulatory Impact Analysis, available at
www.regulations.gov.

D. Executive Order 13132

    This final rule was analyzed in accordance with the principles and
criteria contained in Executive Order 13132, ``Federalism,'' 64 FR
43255. E.O. 13132 requires agencies to assure meaningful and timely
input by State and local officials in the development of regulatory
policies that may have ``substantial direct effects on the States, on
the relationship between the national government and the States, or on
the distribution of power and responsibilities among the various levels
of government.'' This final rule may preempt State, local, and Native
American tribal requirements but does not propose any regulation that
has substantial direct effects on the States, the relationship between
the National Government and the States, or the distribution of power
and responsibilities among the various levels of government. Therefore,
the consultation and funding requirements of Executive Order 13132 do
not apply.
    The Federal Hazardous Materials Transportation Law contains an
express preemption provision, 49 U.S.C. 5125(b), that preempts State,
local, and Native American tribal requirements on the following
subjects unless the non-Federal requirements are ``substantively the
same'' as the Federal requirements:
    (1) The designation, description, and classification of hazardous
materials;
    (2) The packing, repacking, handling, labeling, marking, and
placarding of hazardous materials;
    (3) The preparation, execution, and use of shipping documents
related to hazardous materials and requirements related to the number,
contents, and placement of those documents;

    (4) The written notification, recording, and reporting of the
unintentional release in transportation of hazardous material; and
    (5) The design, manufacture, fabrication, marking, maintenance,
recondition, repair, or testing of a packaging or container
represented, marked, certified, or sold as qualified for use in
transporting hazardous material.
    This final rule addresses subjects (1), (2), and (5) above.
Therefore, this final rule will preempt any State, local, or tribal
requirements concerning these subjects unless the non-Federal
requirements are ``substantively the same'' as the Federal
requirements. PHMSA received no comments on the NPRM regarding the
effect of the adoption of the specific proposals would have on State or
local governments.

E. Executive Order 13175

    This final rule was analyzed in accordance with the principles and
criteria contained in Executive Order 13175, ``Consultation and
Coordination with Indian Tribal Governments,'' 79 FR 4748. E.O. 13175
requires agencies to assure meaningful and timely input from Indian
tribal government representatives in the development of rules that
significantly or uniquely affect Tribal communities by imposing
``substantial direct compliance costs'' or ``substantial direct
effects'' on such communities or the relationship and distribution of
power between the Federal Government and Indian tribes. This final rule
is generally directed at offerors and shippers of DOT-specification
cylinders and UN pressure receptacles that transport hazardous
materials in U.S. commerce. The final rule is also likely to affect
cylinder manufacturers; cylinder requalifiers; independent inspection
agencies; commercial establishments that own and use DOT-specification
cylinders and UN pressure receptacles. It does not impose substantial
direct compliance costs and does not have substantial direct effects on
Native American tribal governments. Therefore, the funding and
consultation requirements of E.O. 13175 do not apply, and a tribal
summary impact statement is not required. Further, PHMSA did not
receive comments on the tribal implications of the rulemaking.

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

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires an
agency to review regulations to assess their impact on small entities
unless the agency determines that a rule is not expected to have a
significant impact on a substantial number of small entities. Executive
Order 13272, ``Proper Consideration of Small Entities in Agency
Rulemaking,'' 68 FR 7990, requires agencies to establish procedures and
policies to promote compliance with the Regulatory Flexibility Act and
to ``thoroughly review draft rules to assess and take appropriate
account of the potential impact'' of the rules on small businesses,
governmental jurisdictions and small organizations. This rule was
developed in accordance with this E.O. and DOT's procedures and
policies to promote compliance with the Regulatory Flexibility Act to
ensure that potential impacts on small entities of a regulatory action
were properly considered.
    Section 603(b) of the Regulatory Flexibility Act requires an
analysis of the possible impact of the rule on small entities,
including the need for the rule, the description of the action, the
identification of potentially affected small entities, the reporting
and recordkeeping requirements, the related Federal rules and
regulations, and the alternative proposals considered. Such analysis
for this final rule is as follows:
1. Need for the Final Rule
    Current requirements for the manufacture, use, and requalification
of cylinders can be traced to standards first applied in the early
1900s. Over the years, the regulations have been revised to reflect
advancements in transportation efficiency and changes in the national
and international economic environment. This final rule is part of an
agency effort to conduct a retrospective review of existing
regulations. The final rule attempts to modify and streamline existing
requirements that are outmoded, ineffective, insufficient, or
excessively burdensome. As part of this effort, this rulemaking
introduces new provisions suggested or developed by industry
representatives, groups that develop consensus standards, and
international regulatory bodies.
2. Description of Action
    This final rule responds to 20 petitions for rulemaking, clarifies
other requirements in the HMR, and addresses areas of concern that are
currently left out of the HMR. The amendments discussed in this final
rule are designed to increase flexibility for the regulated community,
promote technological advancement, and facilitate international
transportation while maintaining a comparable level of safety.
3. Identification of Potentially Affected Small Entities
    The term ``small entities,'' as described in 5 U.S.C. 601,
comprises small businesses and not-for-profit organizations that are
independently owned and operated and are not dominant in their fields
and governmental jurisdictions with populations of less than 50,000.
The amendments considered here are likely to affect cylinder
manufacturers (NAICS code 332420; approximately 568 companies);
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 (NAICS codes 32512, 336992, 423450, 423850, 423990,
454312, and 541380). Nearly all of these companies, particularly
cylinder requalification facilities (approximately 5,000 in total) are
small entities based on the criteria developed by the Small Business
Administration.
4. Reporting and Recordkeeping Requirements
    This final rule includes very minor reporting and recordkeeping
requirements.
5. Related Federal Rules and Regulations
    The Occupational Safety and Health Administration (OSHA) prescribes
requirements for the use, maintenance, and testing of portable fire
extinguishers in 29 CFR 1910.157 and requirements for fixed fire
suppression systems in 29 CFR 1910.160. The issues discussed in this
final rule pertaining to the transportation of fire extinguishers and
compressed gas cylinders that are a component of a fixed fire
suppression system do not conflict with the requirements in OSHA
regulations. With respect to the transportation of compressed gases in
cylinders, there are not related rules or regulations issued by other
departments or agencies of the Federal government.
6. Alternative Proposals for Small Business
    The Regulatory Flexibility Act directs agencies to establish
exceptions and differing compliance standards for small businesses,
where it is possible to do so and still meet the objectives of
applicable regulatory statutes. The proposed changes are generally
intended to provide cost savings to industry members. PHMSA received no

comments from small entities on specific small business impacts from
these additional requirements.
7. Conclusion
    This final rule reduces burdens for most persons and any costs
resulting from adoption of new requirements will be minimal and will be
offset by cost savings. Additionally, the rule will create additional
unquantified ancillary benefits and cost savings derived from
increasing regulatory flexibility and improving safety through enhanced
clarity.

G. Paperwork Reduction Act

    PHMSA has analyzed this rule in accordance with the Paperwork
Reduction Act of 1995 (PRA) (Pub. L. 96-511). PHMSA stated in the NPRM
that the proposals did not impose new information collection
requirements. However, PHMSA did receive a comment from Hydro-Test
Products related to proposed changes to Sec.  180.215 on the addition
of the date of manufacture to test record forms. The commenter noted
that PHMSA did not address the paperwork burden for the proposed
requirement in Sec.  180.215. To address this comment PHMSA is
accounting for a minor adjustment to information on a requalification
test report under OMB control number 2137-0022 titled ``Testing,
Inspection, and Marking Requirements for Cylinders.'' PHMSA estimates
based on our experience observing the activities of cylinder
requalifiers during compliance inspections that it will take one
additional second to write the date of manufacture on the cylinder
requalification record. PHMSA currently estimates there are 6,790,000
cylinder requalifications conducted each year. The additional one
second of burden to these reports will result in additional time burden
of 1,886 hours (6,790,000 annual reports x 1 second).
    Furthermore, upon review of this rule, PHMSA is accounting for
additional burden in this rulemaking. In the NPRM, PHMSA also proposed
a requirement in Sec.  178.35 to mark the tare weight, mass weight, and
water capacity on DOT 4B, 4BA, 4BW, or 4E cylinders. The language in
the final rule will codify language in Sec.  178.35 to require that
DOT-specification 4B, 4BA, 4BW, and 4E cylinders used in liquefied
compressed gas service manufactured two years after publication of this
rule to be marked with the tare weight, mass weight, and water
capacity. PHMSA already accounts for the marking of new cylinders under
Sec.  178.35 under the previously mentioned OMB Control Number 2137-
0022. PHMSA estimates based on our knowledge of modern automated
cylinder manufacturing processes from direct observation during
compliance inspections that this additional marking information will
take an additional 3 minutes, for an increase in approximately 3,472
hours on an annual basis.
    Additionally, PHMSA proposed a requirement in Sec.  180.215(b)(4)
to require cylinder requalifiers to retain the most recent calibration
certificate for their pressure indicating device (PID) and expansion
indicating device (EID). PHMSA already accounts for creation of records
related to cylinder requalification under Sec.  180.215 under OMB
Control Number 2137-0022. After the incorporation of CGA C-1, each
requalifier will be required to re-calibrate their PID every 6 months.
There are approximately 2,300 cylinder requalifiers approved by PHMSA
to conduct pressure tests on cylinders, therefore we estimate that
4,600 PID calibration certificates will be generated each year. We
estimate that it will take the gauge calibration facility 5 minutes to
generate each certificate, based on our knowledge of the information
contained on the certificate. This results in a new information
collection burden of approximately 383 hours for gauge calibration
facilities. Based on our experience inspecting cylinder requalification
facilities, we believe that gauge calibration facilities already
provide this record as part of their business practices and there will
be no additional cost burden associated with this requirement.
    Expansion indicating devices (EIDs) are either burette systems or
scale-based systems. Burette systems do not require recalibration
because their accuracy is fixed at the time the glass burette tube is
measured and printed with volume graduations. CGA C-1 requires that
scale-based EID systems are recalibrated as provided in the
manufacturer's manual. PHMSA has reviewed a manufacturer's manual for a
scale-based system and determined that scale calibration is only
required when the scale cannot display an accurate weight when tested
with an object of known mass (e.g. a 100-gram test weight provided with
the system). Based on our experience conducting inspections at cylinder
requalification facilities, this is an uncommon occurrence. Based on
our experience inspecting cylinder requalification facilities, we
estimate that 10% of cylinder requalifiers need to recalibrate their
scale-based EID systems each year, resulting in the generation of 230
re-calibration certificates annually. We estimate that it will take the
scale calibration facility 5 minutes to generate each certificate,
based on our knowledge of the information contained on the certificate,
which results in an increase of approximate 19 hours in burden. Based
on our experience inspecting cylinder requalification facilities, we
believe that scale calibration facilities already provide this record
as part of their business practices and there will be no additional
cost burden associated with this requirement.
    Finally, PHMSA proposed a requirement in Sec. Sec.  178.50(b),
178.51(b), 178.61(b), and 178.68(b) to require manufacturers of DOT 4B,
4BA, 4BW, and 4E cylinders to keep a record of intentionally added
alloying elements in the steel or aluminum used to produce the
cylinders. PHMSA already accounts for recordkeeping related to the
production of cylinders under OMB Control Number 2137-0022. PHMSA
estimates based on our knowledge of cylinder manufacturer practices
from direct observation during compliance inspections that this
additional recordkeeping will take an additional 23 hours affecting 23
manufacturers.
    This rulemaking identifies revised information collection requests
that PHMSA will submit to OMB for approval based on the requirements in
this final rule. PHMSA has developed burden estimates to reflect
changes in this final rule and estimates the information collection and
recordkeeping burdens in this rule are as follows:
    Annual Increase in Number of Respondents: 4,623.
    Annual Increase in Annual Number of Responses: 4,853.
    Annual Increase in Annual Burden Hours: 5,783.

H. Regulation Identifier Number (RIN)

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

I. Unfunded Mandates Reform Act of 1995

    The Unfunded Mandates Reform Act (UMRA) of 1995, Public Law 104-4,
establishes significance thresholds for the direct costs of regulations
on State, local, or tribal governments or the private sector that
trigger certain agency reporting requirements. The statutory thresholds
established in UMRA were $50 million for intergovernmental mandates and
$100 million for private-

sector mandates in 1996. According to the Congressional Budget Office,
the thresholds for 2019, which are adjusted annually for inflation, are
$82 million and $164 million, respectively, for intergovernmental and
private-sector mandates.\12\ This final rule results in cost savings
and is the least burdensome alternative that achieves the objective of
the rule. It is not significant under UMRA. Therefore, PHMSA is not
required to prepare a written statement.
---------------------------------------------------------------------------

    \12\ https://www.cbo.gov/publication/51335.
---------------------------------------------------------------------------

J. Environmental Assessment

    The National Environmental Policy Act of 1969 (NEPA), as amended
(42 U.S.C. 4321-4347), and implementing regulations by the Council on