Document ID: PHMSA-2021-0092-0003
Agency: phmsa
Document Type: Proposed Rule
Title: Hazardous Materials: Harmonization With International Standards
Posted Date: 2023-05-30T04:00Z

[Federal Register Volume 88, Number 103 (Tuesday, May 30, 2023)]
[Proposed Rules]
[Pages 34568-34622]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-07109]

[[Page 34567]]

Vol. 88

Tuesday,

No. 103

May 30, 2023

Part II

Department of Transportation

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Pipeline and Hazardous Materials Safety Administration

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49 CFR Parts 171, 172, et al.

Hazardous Materials: Harmonization With International Standards; 
Proposed Rule

  Federal Register / Vol. 88 , No. 103 / Tuesday, May 30, 2023 / 
Proposed Rules  

[[Page 34568]]

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DEPARTMENT OF TRANSPORTATION

Pipeline and Hazardous Materials Safety Administration

49 CFR Parts 171, 172, 173, 175, 176, 178, and 180

[Docket No. PHMSA-2021-0092 (HM-215Q)]
RIN 2137-AF57

Hazardous Materials: Harmonization With International Standards

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: PHMSA proposes to amend the Hazardous Materials Regulations to 
maintain alignment with international regulations and standards by 
adopting various amendments, including changes to proper shipping 
names, hazard classes, packing groups, special provisions, packaging 
authorizations, air transport quantity limitations, and vessel stowage 
requirements.

DATES: Comments must be received by July 31, 2023. To the extent 
possible, PHMSA will consider late-filed comments while a final rule is 
developed.

ADDRESSES: You may submit comments by any of the following methods:
     Federal Rulemaking Portal: http://www.regulations.gov. 
Follow the online instructions for submitting comments.
     Fax: 1-202-493-2251.
     Mail: Docket Management System; U.S. Department of 
Transportation, Docket Operations, M-30, Ground Floor, Room W12-140, 
1200 New Jersey Avenue SE, Washington, DC 20590-0001.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, Ground Floor, Room W12-140, 1200 New Jersey Avenue 
SE, Washington, DC 20590-0001 between 9 a.m. and 5 p.m., Monday through 
Friday, except federal holidays.
    Instructions: Include the agency name and docket number PHMSA-2021-
0092 (HM-215Q) or RIN 2137-AF57 for this rulemaking at the beginning of 
your comment. Note that all comments received will be posted without 
change to http://www.regulations.gov including any personal information 
provided. If sent by mail, comments must be submitted in duplicate. 
Persons wishing to receive confirmation of receipt of their comments 
must include a self-addressed stamped postcard.
    Docket: For access to the dockets to read background documents 
(including the Preliminary Regulatory Impact Analysis (PRIA)) or 
comments received, go to http://www.regulations.gov or DOT's Docket 
Operations Office (see ADDRESSES).
    Confidential Business Information: Confidential Business 
Information (CBI) is commercial or financial information that is both 
customarily and actually treated as private by its owner. Under the 
Freedom of Information Act (FOIA; 5 U.S.C. 552), CBI is exempt from 
public disclosure. If your comments responsive to this NPRM contain 
commercial or financial information that is customarily treated as 
private, that you actually treat as private, and that is relevant or 
responsive to this NPRM, it is important that you clearly designate the 
submitted comments as CBI. Please mark each page of your submission 
containing CBI as ``PROPIN.'' Submissions containing CBI should be sent 
to Candace Casey, U.S. Department of Transportation, 1200 New Jersey 
Avenue SE, Washington, DC 20590-0001. Any commentary that PHMSA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

FOR FURTHER INFORMATION CONTACT: Candace Casey, Standards and 
Rulemaking, or Aaron Wiener, International Program, at 202-366-8553, 
Pipeline and Hazardous Materials Safety Administration, U.S. Department 
of Transportation, 1200 New Jersey Avenue SE, East Building, 2nd Floor, 
Washington, DC 20590-0001.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Executive Summary
II. Background
III. Incorporation by Reference Discussion Under 1 CFR Part 51
IV. Amendments Not Being Proposed for Adoption
V. Section-by-Section Review of NPRM Proposals
VI. Regulatory Analyses and Notices
    A. Statutory/Legal Authority for This Rulemaking
    B. Executive Order 12866 and DOT Regulatory Policies and 
Procedures
    C. Executive Order 13132
    D. Executive Order 13175
    E. Regulatory Flexibility Act, Executive Order 13272, and DOT 
Policies and Procedures
    F. Paperwork Reduction Act
    G. Unfunded Mandates Reform Act of 1995
    H. Environment Assessment
    I. Executive Order 12898
    J. Privacy Act
    K. Executive Order 13609 and International Trade Analysis
    L. National Technology Transfer and Advancement Act
    M. Executive Order 13211

I. Executive Summary

    The Pipeline and Hazardous Materials Safety Administration (PHMSA) 
proposes to amend certain sections of the Hazardous Materials 
Regulations (HMR; 49 CFR parts 171 to 180) to maintain alignment with 
international regulations and standards by adopting various changes, 
including changes to proper shipping names (PSN), hazard classes, 
packing groups (PG), special provisions (SP), packaging authorizations, 
air transport quantity limitations, and vessel stowage requirements. 
The proposed amendments are discussed in detail in ``Section V. 
Section-by-Section Review of NPRM Proposals.''
    Adoption of the regulatory amendments proposed in this NPRM will 
maintain the high safety standard currently achieved under the HMR. 
PHMSA also notes that because harmonization of the HMR with 
international regulations and consensus standards could reduce delays 
and interruptions of hazardous materials during transportation, the 
proposed amendments may also lower greenhouse gas (GHG) emissions and 
safety risks to minority, low-income, underserved, and other 
disadvantaged populations and communities in the vicinity of interim 
storage sites and transportation arteries and hubs.
    The following list summarizes noteworthy proposals set forth in 
this NPRM:
     Incorporation by Reference: PHMSA proposes to incorporate 
by reference updated versions of the following international hazardous 
materials regulations and standards: the 2023-2024 edition of the 
International Civil Aviation Organization Technical Instructions for 
the Safe Transport of Dangerous Goods by Air (ICAO Technical 
Instructions); Amendment 41-22 to the International Maritime Dangerous 
Goods Code (IMDG Code); and the 22nd revised edition of the United 
Nations Recommendations on the Transport of Dangerous Goods--Model 
Regulations (UN Model Regulations);
     Hazardous Materials Table: PHMSA proposes amendments to 
the Hazardous Materials Table (HMT; 49 CFR 172.101) to add, revise, or 
remove certain PSNs, hazard classes, PGs, SPs, packaging 
authorizations, bulk packaging requirements, and passenger and cargo 
aircraft maximum quantity limits.

[[Page 34569]]

     Polymerizing Substances: In 2017--as part of the HM-215N 
final rule \1\--PHMSA added four new Division 4.1 (flammable solid) 
entries for polymerizing substances to the HMT and added defining 
criteria, authorized packagings, and safety requirements including, but 
not limited to, stabilization methods and operational controls into the 
HMR. These changes remained in effect until January 2, 2019, while 
PHMSA used the interim period to review and research the implications 
of the polymerizing substance amendments. In 2020--as part of the HM-
215O \2\ final rule--PHMSA extended the date the provisions remained in 
effect from January 2, 2019, to January 2, 2023, to allow for the 
additional research to be completed on the topic. In this NPRM, PHMSA 
proposes to remove the phaseout date (January 2, 2023) from the 
transport provisions for polymerizing substances to allow for continued 
use of the provisions.
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    \1\ 82 FR 15796 (Mar. 30, 2017).
    \2\ 85 FR 27810 (May 11, 2020).
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     Cobalt dihydroxide powder containing not less than 10 
percent respirable particles: PHMSA proposes to add a new entry to HMT, 
``UN3550 Cobalt dihydroxide powder, containing not less than 10% 
respirable particles'' and corresponding packaging provisions. Cobalt 
is a key strategic mineral used in various advanced medical and 
technical applications around the world, including various types of 
batteries. Historically, this hazardous material has been classified 
and transported as a Class 9 material under ``UN3077, Environmentally 
hazardous substance, solid, n.o.s.'' however testing required under 
Registration, Evaluation, Authorisations and Restriction of Chemicals 
(REACH) regulations \3\ for comprehensive GHS testing, determined that 
this material poses an inhalation toxicity hazard. Following this 
determination, the 22nd revised edition of the UN Model Regulations 
developed a new entry on the Dangerous Goods List (DGL) and packaging 
authorizations specifically for this hazardous material to facilitate 
continued global transport of this material. In this NPRM, PHMSA 
proposes to do likewise by adding a new entry for cobalt dihydroxide 
containing not less than 10 percent respirable particles and assigning 
it UN3550 on the HMT, in addition to adding packaging provisions, 
including the authorization to transport this material in flexible 
IBCs. PHMSA expects that these provisions will facilitate the continued 
transport of this material, to keep global supply chains open. See 
172.101 of the Section-by-Section Review for additional discussion of 
these amendments.
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    \3\ Regulation (EC) No 1907/2006 of the European Parliament and 
of the Council of 18 December 2006.
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     Lithium Battery Exceptions: PHMSA proposes to remove the 
exceptions provided for small lithium cells and batteries for 
transportation by aircraft. This is consistent with the elimination of 
similar provisions in the ICAO Technical Instructions. See 173.185 of 
the Section-by-Section Review for additional discussion of these 
amendments.
    All the proposed amendments are expected to maintain the HMR's high 
safety standard for the public and the environment. Additionally, PHMSA 
anticipates that there are safety benefits to be derived from improved 
compliance related to consistency amongst domestic and international 
regulations. PHMSA solicits comment on the amendments proposed in this 
NPRM pertaining to the need, benefits, and costs of the proposed HMR 
revisions; impact on safety and the environment; impact on 
environmental justice and equity; and any other relevant information. 
In addition, PHMSA solicits comment regarding approaches to reducing 
the costs of this rule while maintaining or increasing safety benefits. 
As further explained in the PRIA, PHMSA expects that the aggregate 
benefits of the amendments proposed in this NPRM justify their 
aggregate costs. Nonetheless, PHMSA solicits comment on specific 
changes (e.g., greater flexibility with regard to a particular 
proposal) that might improve the rule.

II. Background

    The Federal Hazardous Materials Transportation Law (49 U.S.C. 5101, 
et seq.) directs PHMSA to participate in relevant international 
standard-setting bodies and encourages alignment of the HMR with 
international transport standards, as consistent with promotion of 
safety and the public interest. See 49 U.S.C. 5120. This statutory 
mandate reflects the importance of international standard-setting 
activity, in light of the globalization of commercial transportation of 
hazardous materials. Harmonization of the HMR with those efforts can 
reduce the costs and other burdens of complying with multiple or 
inconsistent safety requirements between nations. Consistency between 
the HMR and current international standards can also enhance safety by 
(1) ensuring that the HMR are informed by the latest best practices and 
lessons learned; (2) improving understanding of, and compliance with, 
pertinent requirements; (3) facilitating the flow of hazardous 
materials from their points of origin to their points of destination, 
thereby avoiding risks to the public and the environment from release 
of hazardous materials due to delays or interruptions in the 
transportation of those materials; and (4) enabling consistent 
emergency response procedures in the event of a hazardous materials 
incident.
    PHMSA participates in the development of international regulations 
and standards for the transportation of hazardous materials. It also 
adopts within the HMR international consensus standards and regulations 
consistent with PHMSA's safety mission. PHMSA reviews and evaluates 
each international standard it considers for incorporation within the 
HMR on its own merits, including the effects on transportation safety, 
the environmental impacts, and any economic impact. PHMSA's goal is to 
harmonize with international standards without diminishing the level of 
safety currently provided by the HMR or imposing undue burdens on the 
regulated community.
    In final rule HM-181,\4\ PHMSA's predecessor, the Research and 
Special Programs Administration (RSPA), comprehensively revised the HMR 
for greater consistency with the UN Model Regulations. The UN Model 
Regulations constitute a set of recommendations issued by the United 
Nations Sub-Committee of Experts (UNSCOE) on the Transport of Dangerous 
Goods and on the Globally Harmonized System of Classification and 
Labelling of Chemicals (GHS). The UN Model Regulations are amended and 
updated biennially by the UNSCOE and serve as the basis for national, 
regional, and international modal regulations, including the ICAO 
Technical Instructions and IMDG Code.
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    \4\ 55 FR 52401 (Dec. 21, 1990).
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    PHMSA has evaluated recent updates to the international standards, 
including review of numerous updated standards for the design, 
manufacture, testing, and use of packagings, and proposes to revise the 
HMR to adopt changes consistent with revisions to the 2023-2024 edition 
of the ICAO Technical Instructions, Amendment 41-22 to the IMDG Code, 
and the 22nd revised edition of the UN Model Regulations, all of which 
will be published by or in effect on January 1, 2023,\5\ while also 
ensuring the changes are consistent with

[[Page 34570]]

PHMSA's safety mission. Consequently, PHMSA proposes to incorporate by 
reference these revised international regulations, several new or 
updated International Organization for Standards (ISO) standards, and a 
new Organization for Economic Co-operation and Development (OECD) 
standard. The regulations and standards incorporated by reference are 
authorized for use for domestic transportation, under specific 
conditions, in part 171, subpart C of the HMR.
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    \5\ Amendment 41-22 of the IMDG Code will become mandatory on 
January 1, 2024. Voluntary compliance begins on January 1, 2023.
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    PHMSA issued an enforcement discretion on November 28, 2022,\6\ 
stating that while PHMSA is considering the 2023-2024 Edition of the 
ICAO Technical Instructions and Amendment 41-22 of the IMDG Code for 
potential adoption into the HMR, PHMSA and other federal agencies that 
enforce the HMR (the Federal Railroad Administration (FRA), the Federal 
Aviation Administration (FAA), the Federal Motor Carrier Safety 
Administration (FMCSA), and the United States Coast Guard (USCG)) will 
not take enforcement action against any offeror or carrier who uses 
these standards as an alternative to complying with current HMR 
requirements when all or part of the transportation is by air with 
respect to the ICAO Technical Instructions, or by vessel with respect 
to the IMDG Code. In addition, PHMSA and its partners will not take 
enforcement action against any offeror or carrier who offers or accepts 
for domestic or international transportation by any mode packages 
marked or labeled in accordance with these standards. This notice 
remains in effect until withdrawn or otherwise modified.
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    \6\ https://www.phmsa.dot.gov/regulatory-compliance/phmsa-guidance/phmsa-notice-enforcement-policy-regarding-international.
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III. Incorporation by Reference Discussion Under 1 CFR Part 51

    According to the Office of Management and Budget (OMB), Circular A-
119, ``Federal Participation in the Development and Use of Voluntary 
Consensus Standards and in Conformity Assessment Activities,'' 
government agencies must use voluntary consensus standards wherever 
practical in the development of regulations.
    PHMSA currently incorporates by reference into the HMR all or parts 
of numerous standards and specifications developed and published by 
standard development organizations (SDO). In general, SDOs update and 
revise their published standards every two to five years to reflect 
modern technology and best technical practices. The National Technology 
Transfer and Advancement Act of 1995 (NTTAA; Pub. L. 104-113) directs 
federal agencies to use standards developed by voluntary consensus 
standards bodies in lieu of government-written standards whenever 
possible. Voluntary consensus standards bodies develop, establish, or 
coordinate technical standards using agreed-upon procedures. OMB issued 
Circular A-119 to implement section 12(d) of the NTTAA relative to the 
utilization of consensus technical standards by federal agencies. This 
circular provides guidance for agencies participating in voluntary 
consensus standards bodies and describes procedures for satisfying the 
reporting requirements in the NTTAA. Accordingly, PHMSA is responsible 
for determining which standards currently referenced in the HMR should 
be updated, revised, or removed, and which standards should be added to 
the HMR. Revisions to materials incorporated by reference in the HMR 
are handled via the rulemaking process, which allows for the public and 
regulated entities to provide input. During the rulemaking process, 
PHMSA must also obtain approval from the Office of the Federal Register 
to incorporate by reference any new materials. The Office of the 
Federal Register issued a rulemaking \7\ that revised 1 CFR 51.5 to 
require that an agency detail in the preamble of an NPRM the ways the 
materials it proposes to incorporate by reference are reasonably 
available to interested parties, or how the agency worked to make those 
materials reasonably available to interested parties. Proposed changes 
to the material incorporated by reference in the HMR are discussed in 
detail in the Sec.  171.7 discussion in ``Section V. Section-by-Section 
Review of NPRM Proposals.''
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    \7\ 79 FR 66278 (Nov. 7, 2014).
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    The UN Model Regulations, the United Nations Manual of Tests and 
Criteria (UN Manual of Tests and Criteria),\8\ and the OECD standard 
(i.e., Test No. 439) are free and easily accessible to the public on 
the internet, with access provided through the parent organization 
websites. The ICAO Technical Instructions, IMDG Code, and all ISO 
standard references are available for interested parties to purchase in 
either print or electronic versions through the parent organization 
websites. The price charged for those references not freely available 
helps to cover the cost of developing, maintaining, hosting, and 
accessing these standards and regulations.
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    \8\ U.N. Econ. Comm'n for Europe, Transportation Division, 
Manual of Tests and Criteria, 7th Rev. Ed., Amend. 1, U.N. Sales No. 
21. VIII. 2 (2021).
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IV. Amendments Not Being Proposed for Adoption

    PHMSA determined that certain elements of updated international 
regulations and standards should not be adopted into the HMR because 
the structure of the HMR is such that it makes adoption unnecessary, or 
PHMSA has deemed it is a safer approach to authorize certain transport 
requirements through issuance of a special permit rather than allow for 
general applicability by adopting those requirements into the HMR. Use 
of a special permit allows for greater oversight and development of 
transport history and data prior to determining whether to adopt the 
terms of the special permit in the HMR for broad application.
    The following is a list of international regulations and standards 
updates that PHMSA is not proposing for adoption in this NPRM, and the 
rationale for those decisions:
     Fiber-reinforced plastic UN portable tanks: The 22nd 
revised edition of the UN Model Regulations and Amendment 41-22 of the 
IMDG Code include provisions for the design, construction, approval, 
use, and testing of fiber-reinforced plastic (FRP) UN portable tanks. 
These are UN portable tanks with shells made of FRP materials instead 
of traditional steel. PHMSA is not proposing to make corresponding 
amendments to the HMR to authorize general multi-modal transport of FRP 
UN portable tanks. PHMSA believes further research is necessary in 
areas covering material fatigue, suitability of the pool fire test and 
impact testing as packaging qualification methods, and in the 
identification of the most appropriate non-destructive test methodology 
to qualify FRP UN portable tanks. The results of this research will be 
used to better gauge the appropriateness of full adoption of the 
provisions, amendments to the requirements for approval or use, or a 
continued exclusion from the HMR. However, PHMSA is proposing an 
amendment to Sec.  171.25--Additional requirements for the use of the 
IMDG Code--that would allow limited import and export of FRP UN 
portable tanks within a single port area. See ``Section V. Section-by-
Section Review of NPRM Proposals'' for a discussion of Sec.  171.25 
changes.
     Pressure receptacles: The 22nd revised edition of the UN 
Model Regulations, the 2023-2024 edition of the ICAO Technical 
Instructions, and Amendment 41-22 to the IMDG Code

[[Page 34571]]

amended various definitions and other language concerning the terms 
``pressure receptacles'' and associated requirements for assessing 
conformance of UN cylinders built to ISO standards. PHMSA is not 
proposing to make changes to the HMR consistent with these amendments. 
Terminology used in international standards and HMR differ such that an 
evaluation is necessary to determinate the full impacts beyond merely 
using consistent terminology. PHMSA may consider making relevant 
changes regarding UN cylinders as needed in future rulemakings.
     Aerosol containers: The 22nd revised edition of the UN 
Model Regulations, the 2023-2024 edition of the ICAO Technical 
Instructions, and Amendment 41-22 to the IMDG Code adopted maximum 
internal pressure limits for aerosol containers. Prior to these 
changes, these international regulations and standards had no specific 
pressure limits for aerosol containers. PHMSA welcomes this additional 
safety measure for the transport of aerosol containers, as it makes 
aerosol containers constructed and filled in accordance with 
international standards more consistent with existing domestic 
requirements for aerosol containers, which are subject to internal 
pressure limits as part of the performance standards for their 
construction and use. Noting existing differences in the HMR, include 
the definition for aerosol and the performance standards for their 
construction and use and thus because of the complexity involved in 
trying to harmonize the maximum pressure limits, PHMSA is not proposing 
to adopt these internationally implemented maximum internal pressure 
limits. Such harmonization would necessitate a review and evaluation 
beyond the scope of this rulemaking.

V. Section-by-Section Review of NPRM Proposals

    The following is a section-by-section review of proposed amendments 
to harmonize the HMR with international regulations and standards.

A. Part 171

Section 171.7
    Section 171.7 provides a listing of all voluntary consensus 
standards incorporated by reference into the HMR, as directed by the 
NTTAA. PHMSA evaluated updated international consensus standards 
pertaining to PSNs, hazard classes, PGs, special provisions, packaging 
authorizations, air transport quantity limitations, and vessel stowage 
requirements. PHMSA contributed to the development of those standards--
each of which build on the well-established and documented safety 
histories of earlier editions--as it participated in the discussions 
and working group activities associated with their proposal, revision, 
and approval. Those activities, in turn, have informed PHMSA's 
evaluation of the effect the updated consensus standards would have on 
safety, when incorporated by reference and with provisions adopted into 
the HMR. Further, PHMSA notes that some of the consensus standards 
proposed for incorporation by reference within the HMR in this 
rulemaking have already been adopted into the regulatory schemes of 
other countries. Additionally, as noted above, PHMSA has issued past 
enforcement discretions authorizing their use of the consensus 
standards as an interim strategy for complying with current HMR 
requirements. PHMSA is not aware of adverse safety impacts from that 
operational experience. For these reasons, PHMSA expects their 
incorporation by reference will maintain the high safety standard 
currently achieved under the HMR. Therefore, PHMSA proposes to add or 
revise the following incorporation by reference materials.\9\
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    \9\ All other standards that are set out as part of the 
regulatory text of Sec.  171.7(w) were previously approved for 
incorporation by reference and no changes are proposed.
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     In paragraph (t)(1), incorporate by reference the 2023-
2024 edition of the ICAO Technical Instructions, to replace the 2021-
2022 edition, which is currently referenced in Sec. Sec.  171.8; 171.22 
through 171.24; 172.101; 172.202; 172.401; 172.407; 172.512; 172.519; 
172.602; 173.56; 173.320; 175.10, 175.33; and 178.3. The ICAO Technical 
Instructions specify detailed instructions for the international safe 
transport of dangerous goods by air. The requirements in the 2023-2024 
edition have been amended to align better with the 22nd revised edition 
of the UN Model Regulations and the International Atomic Energy Agency 
(IAEA) Regulations for the Safe Transport of Radioactive Material. 
Notable changes in the 2023-2024 edition of the ICAO Technical 
Instructions include new packing and stowage provisions, new and 
revised entries on its Dangerous Goods List, and editorial corrections. 
The 2023-2024 edition of the ICAO Technical Instructions is available 
for purchase on the ICAO website at https://store.icao.int/en/shop-by-areas/safety/dangerous-goods.
     In paragraph (v)(2), incorporate by reference the 2022 
edition of the IMDG Code, Incorporating Amendment 41-22 (English 
Edition), to replace Incorporating Amendment 40-20, 2020 Edition, which 
is currently referenced in Sec. Sec.  171.22; 171.23; 171.25; 172.101; 
172.202; 172.203; 172.401; 172.407; 172.502; 172.519; 172.602; 173.21; 
173.56; 176.2; 176.5; 176.11; 176.27; 176.30; 176.83; 176.84; 176.140; 
176.720; 176.906; 178.3; and 178.274. The IMDG Code is a unified 
international code that outlines standards and requirements for the 
transport of dangerous goods by sea (i.e., by vessel). Notable changes 
in Amendment 41-22 of the IMDG Code include new packing and stowage 
provisions, new and revised entries on its Dangerous Goods List, and 
editorial corrections. Distributors of the IMDG Code can be found on 
the International Maritime Organization (IMO) website at: https://www.imo.org/en/publications/Pages/Distributors-default.aspx.
     In paragraph (w), incorporate by reference or remove the 
following ISO documents to include new and updated standards for the 
specification, design, construction, testing, and use of gas cylinders:

--ISO 9809, Parts 1 through 3. ISO 9809 is comprised of four parts (ISO 
9809-1 through 9809-4) and specifies minimum requirements for the 
material, design, construction, and workmanship; manufacturing 
processes; and examination and testing at time of manufacture for 
various types of refillable seamless steel gas cylinders and tubes. 
PHMSA proposes to incorporate by reference the most recent versions of 
Parts 1 through 3.

     Incorporate by reference the third edition of ISO 9809-
1:2019(E), ``Gas cylinders--Design, construction and testing of 
refillable seamless steel gas cylinders and tubes--Part 1: Quenched and 
tempered steel cylinders and tubes with tensile strength less than 1100 
Mpa'' in paragraph (w)(32). Additionally, PHMSA proposes a sunset date 
of December 31, 2026, for continued use and phase out of the second 
edition of ISO 9809-1:2010, which is currently referenced in Sec.  
178.37, Sec.  178.71, and Sec.  178.75. Part 1 of ISO 9809 is 
applicable to cylinders and tubes for compressed, liquefied, and 
dissolved gases and for quenched and tempered steel cylinders and tubes 
with a maximum actual tensile strength of less than 1100 MPa, which is 
equivalent to U.S. customary unit of about 160,000 psi. As part of its 
periodic review of all standards, ISO reviewed ISO 9809-

[[Page 34572]]

1:2010(E) and published an updated version, ISO 9809-1:2019(E), which 
was published in 2019 and adopted in the 22nd revised edition of the UN 
Model Regulations. The updated standard has technical revisions 
including limiting the bend test only for prototype tests. Updating 
references to this document would align the HMR with changes adopted in 
the 22nd revised edition of the UN Model Regulations pertaining to the 
design and construction of UN cylinders. PHMSA has reviewed this 
edition as part of its regular participation in the review of 
amendments proposed for the UN Model Regulations and concludes 
incorporation of the revised third edition will maintain or improve the 
safety standards associated with its use.
     Incorporate by reference the third edition of ISO 9809-
2:2019(E), ``Gas cylinders--Design, construction and testing of 
refillable seamless steel gas cylinders and tubes--Part 2: Quenched and 
tempered steel cylinders and tubes with tensile strength greater than 
or equal to 1100 MPa'' in paragraph (w)(35). ISO 9809-2:2019 is the 
third edition of ISO 9809-2. Additionally, PHMSA proposes a sunset date 
of December 31, 2026, for continued use and phaseout of the second 
edition of ISO 9809-2:2010, which is currently referenced in Sec.  
178.71, and Sec.  178.75. ISO 9809-2:2019 specifies minimum 
requirements for the material, design, construction and workmanship, 
manufacturing processes, examination and testing at time of manufacture 
for refillable seamless steel gas cylinders and tubes with water 
capacities up to and including 450 L. Part 2 of ISO 9809 is applicable 
to cylinders and tubes for compressed, liquefied, and dissolved gases 
and for quenched and tempered steel cylinders and tubes with an actual 
tensile strength greater than or equal to 1100 MPa. As part of its 
periodic review of all standards, ISO reviewed ISO 9809-2:2010 and 
published an updated version, ISO 9809-2:2019, in 2019; this updated 
version was adopted in the 22nd revised edition of the UN Model 
Regulations. The updated standard has technical revisions including 
expanded cylinder size (i.e., allowed water capacity is extended from 
below 0.5 L to up to and including 450 L); the introduction of specific 
batch sizes for tubes; limiting the bend test only for prototype tests; 
the addition of test requirements for check analysis (tolerances 
modified); and the addition of new test requirements for threads. 
Updating references to this document would align the HMR with changes 
adopted in the 22nd revised edition of the UN Model Regulations 
pertaining to the design and construction of UN cylinders. PHMSA has 
reviewed this edition as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and 
concludes incorporation of the revised third edition will maintain or 
improve the safety standards associated with its use.
     Incorporate by reference the third edition of ISO 9809-
3:2019(E), ``Gas cylinders--Design, construction and testing of 
refillable seamless steel gas cylinders and tubes--Part 3: Normalized 
steel cylinders and tubes'' in paragraph (w)(38). Additionally, PHMSA 
proposes a sunset date of December 31, 2026, for continued use phaseout 
of the second edition of ISO 9809-3:2010, which is currently referenced 
in Sec.  178.71 and Sec.  178.75. ISO 9809-3 is applicable to cylinders 
and tubes for compressed, liquefied, and dissolved gases and for 
normalized or normalized and tempered, steel cylinders and tubes. As 
part of its periodic review of all standards, ISO reviewed ISO 9809-
3:2010 and published an updated version, ISO 9809-3:2019. The updated 
standard has technical revisions including: a wider scope of cylinders 
(i.e., allowed water capacity is extended from below 0.5 L up to and 
including 450 L); the introduction of specific batch sizes for tubes; 
limiting the bend test only for prototype tests; the addition of test 
requirements for check analysis (tolerances modified); and the addition 
of new test requirements for threads. Updating references to the 2019 
edition would align the HMR with changes adopted in the 22nd revised 
edition of the UN Model Regulations, which added this version 
pertaining to the design and construction of UN cylinders. PHMSA has 
reviewed this edition as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and 
concludes incorporation of the revised third edition will maintain or 
improve the safety standards associated with its use.

--Incorporate by reference supplemental amendment ISO 10462:2013/Amd 
1:2019(E), ``Gas cylinders--Acetylene cylinders--Periodic inspection 
and maintenance--Amendment 1'' in paragraph (w)(48). This proposed 
change would add a reference to ISO 10462:2013/Amd 1:2019(E) in Sec.  
180.207(d)(3), where ISO 10462:2013 is currently required, and add a 
sunset date of December 31, 2024, for continued use and phaseout of ISO 
10462:2013 without the supplemental amendment. ISO 10462:2013 specifies 
requirements for the periodic inspection of acetylene cylinders as 
required for the transport of dangerous goods and for maintenance in 
connection with periodic inspection. It applies to acetylene cylinders 
with and without solvent and with a maximum nominal water capacity of 
150 L. As part of a periodic review of its standards, ISO reviewed ISO 
10462:2013, and in June 2019 published a short supplemental amendment, 
ISO 10462:2013/Amd 1:2019. The supplemental document includes updates 
such as simplified marking requirements for rejected cylinders. 
Updating references to this document would align the HMR with documents 
referenced in the 22nd revised edition of the UN Model Regulations 
pertaining to the requalification procedures for acetylene UN 
cylinders. PHMSA has reviewed this edition as part of its regular 
participation in the review of amendments proposed for the UN Model 
Regulations and concludes the incorporation of the supplemental 
document maintains the HMR safety standards for use of acetylene 
cylinders.
--Incorporate by reference the third edition of ISO 11117:2019(E), 
``Gas cylinders--Valve protection caps and guards--Design, construction 
and tests'' in paragraph (w)(56). This amendment would authorize the 
use of the third edition until further notice and add an end date of 
December 31st, 2026, to the authorization for use of the second 
edition, ISO 11117:2008 and the associated corrigendum, which are 
currently referenced in Sec.  173.301b. ISO 11117 specifies the 
requirements for valve protection caps and valve guards used on 
cylinders for liquefied, dissolved, or compressed gases. The changes in 
this revised standard pertain to the improvement of the 
interoperability of both the valve protection caps and the valve 
guards, with the cylinders and the cylinder valves. To that end, the 
drop test, the marking, and test report requirements have been revised 
and clarified. Updating references to this document would align the HMR 
with changes adopted in the 22nd revised edition of the UN Model 
Regulations pertaining to valve protection on UN pressure receptacles. 
PHMSA has reviewed this edition as part of its regular participation in 
the review of amendments proposed for the UN Model Regulations and does 
not

[[Page 34573]]

expect any degradation of safety standards in association with its use.
--Incorporate by reference ISO 11118:2015/Amd 1:2019(E), ``Gas 
cylinders--Non-refillable metallic gas cylinders--Specification and 
test methods--Amendment 1'' in paragraph (w)(59). ISO 11118:2015/Amd 
1:2019(E) is a short supplemental amendment that is intended to be used 
in conjunction with ISO 11118:2015, which is currently referenced in 
Sec.  178.71. This amendment would authorize the use of this 
supplemental amendment in conjunction with ISO 11118:2015 until further 
notice and add an end date of December 31, 2026, until which ISO 
11118:2015 may continue to be used without this supplemental amendment. 
ISO 11118:2015, which specifies minimum requirements for the material, 
design, inspections, construction and workmanship, manufacturing 
processes, and tests at manufacture of non-refillable metallic gas 
cylinders of welded, brazed, or seamless construction for compressed 
and liquefied gases including the requirements for their non-refillable 
sealing devices and their methods of testing. ISO 11118:2015/Amd 1:2019 
corrects the identity of referenced clauses and corrects numerous 
typographical errors. The amendment also includes updates to the 
marking requirements in the normative Annex A, which includes 
clarifications, corrections, and new testing requirements. Updating 
references to this document would align the HMR with documents 
referenced in the 22nd revised edition of the UN Model Regulations 
pertaining to non-refillable UN cylinders. PHMSA has reviewed this 
amended document as part of its regular participation in the review of 
amendments proposed for the UN Model Regulations and determined that 
the added corrections and clarifications provide important additional 
utility for users of ISO 11118:2015(E) and does not expect any 
degradation of safety standards in association with its use.
--Incorporate by reference ISO 11513:2019, ``Gas cylinders--Refillable 
welded steel cylinders containing materials for sub-atmospheric gas 
packaging (excluding acetylene)--Design, construction, testing, use and 
periodic inspection'' in paragraph (w)(71). ISO 11513:2019 is the 
second edition of ISO 11513. This amendment would authorize the use of 
the second edition and add an end date to the authorization for use of 
the first edition, ISO 11513:2011 (including Annex A), which is 
currently referenced in Sec.  173.302c, Sec.  178.71, and Sec.  
180.207. ISO 11513 specifies minimum requirements for the material, 
design, construction, workmanship, examination and testing at 
manufacture of refillable welded steel cylinders for the sub-
atmospheric pressure storage of liquefied and compressed gases. The 
second edition has been updated to amend packing instructions and 
remove a prohibition on the use of ultrasonic testing during periodic 
inspection. Updating references to this document would align the HMR 
with documents referenced in the 22nd revised edition of the UN Model 
Regulations pertaining to the shipment of adsorbed gases in UN pressure 
receptacles. PHMSA has reviewed this edition as part of its regular 
participation in the review of amendments proposed for the UN Model 
Regulations and does not expect any degradation of safety standards in 
association with its use.
--Incorporate by reference ISO 16111:2018, ``Transportable gas storage 
devices--Hydrogen absorbed in reversible metal hydride'' in paragraph 
(w)(80). ISO 16111:2018 is the second edition of ISO 16111. This 
amendment would authorize the use of the second edition until further 
notice and add an end date of December 31, 2026, on the authorization 
to use the first edition, ISO 16111:2008, which is referenced in 
Sec. Sec.  173.301b, 173.311, and 178.71. ISO 16111 defines the 
requirements applicable to the material, design, construction, and 
testing of transportable hydrogen gas storage systems which utilize 
shells not exceeding 150 L internal volume and having a maximum 
developed pressure not exceeding 25 MPa. This updated standard includes 
additional information pertaining to service temperature conditions 
which have been described in detail; new references related to shell 
design; modified drop test conditions; modified acceptance criteria for 
leak testing; modified hydrogen cycling conditions; new warning 
labelling; and updated information on safety data sheets. Updating 
references to this document would align the HMR with documents 
referenced in the 22nd revised edition of the UN Model Regulations 
pertaining to metal hydride storage systems. PHMSA has reviewed this 
edition as part of its regular participation in the review of 
amendments proposed for the UN Model Regulations and does not expect 
any degradation of safety standards in association with its use.
--Incorporate by reference ISO 17871:2020(E), ``Gas cylinders--Quick-
release cylinder valves--Specification and type testing'' in paragraph 
(w)(83). ISO 17871:2020 is the second edition of ISO 17871. This 
amendment would authorize the use of the second edition and add an end 
date of December 31st, 2026, to the authorization for use of the first 
edition, ISO 17871:2015(E), which is currently referenced in 173.301b. 
This document, in conjunction with ISO 10297 and ISO 14246, specifies 
design, type testing, marking, and manufacturing tests, and 
examinations requirements for quick-release cylinder valves intended to 
be fitted to refillable transportable gas cylinders, pressure drums and 
tubes which convey certain gases such as compressed or liquefied gases 
or extinguishing agents charged with compressed gases to be used for 
fire-extinguishing, explosion protection, and rescue applications. As 
part of its regular review of its standards, ISO updated and published 
the second edition of ISO 17871 as ISO 17871:2020. The 2020 edition of 
this standard broadens the scope to include quick release valves for 
pressure drums and tubes and specifically excludes the use of quick 
release valves with flammable gases. Other notable changes include the 
addition of the valve burst test pressure, the deletion of the flame 
impingement test, and the deletion of internal leak tightness test at -
40 [deg]C for quick release cylinder valves used only for fixed fire-
fighting systems installed in buildings. Updating references to this 
document would align the HMR with changes adopted in the 22nd revised 
edition of the UN Model Regulations pertaining to the shipment of gases 
in UN pressure receptacles. PHMSA has reviewed this edition as part of 
its regular participation in the review of amendments proposed for the 
UN Model Regulations and does not expect any degradation of safety 
standards in association with its use.
--Incorporate by reference ISO 21172-1:2015/Amd 1:2018, ``Gas 
cylinders--Welded steel pressure drums up to 3000 litres capacity for 
the transport of gases--Design and construction--Part 1: Capacities up 
to 1000 litres--Amendment 1'' in paragraph (w)(89). ISO 21172-1:2015/
Amd1:2018 is a short supplemental amendment that is intended to be used 
in conjunction with ISO 21172-1:2015, which is currently referenced in 
Sec.  178.71. This

[[Page 34574]]

amendment would authorize the use of this supplemental document in 
conjunction with the first edition, ISO 21172-1:2015. It would also add 
an end date of December 31, 2026, until which ISO 21172-1:2015 may 
continue to be used without this supplemental amendment. ISO 21172-
1:2015 specifies the minimum requirements for the material, design, 
fabrication, construction, workmanship, inspection, and testing at 
manufacture of refillable welded steel gas pressure drums of volumes 
150 L to 1000 L and up to 300 bar (30 MPa) test pressure for compressed 
and liquefied gases. This supplemental amendment includes updated 
references and removes the restriction on corrosive substances. 
Updating references to this document would align the HMR with documents 
referenced in the 22nd revised edition of the UN Model Regulations 
pertaining to the design and construction of UN pressure drums. PHMSA 
has reviewed this edition as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and does not 
expect any degradation of safety standards in association with its use.
--Incorporate by reference ISO 23088:2020, ``Gas cylinders--Periodic 
inspection and testing of welded steel pressure drums--Capacities up to 
1000 l'' in paragraph (w)(91). This amendment would incorporate by 
reference the first edition of ISO 23088, which specifies the 
requirements for periodic inspection and testing of welded steel 
transportable pressure drums of water capacity from 150 L up to 1,000 L 
and up to 300 bar (30 MPa) test pressure intended for compressed and 
liquefied gases in Sec.  180.207. This new standard was adopted in the 
22nd revised edition of the UN Model Regulations because it fulfills 
the need for specific periodic inspection instructions for pressure 
drums constructed in accordance with ISO 21172-1. Incorporating by 
reference this document would align the HMR with standards adopted in 
the 22nd revised edition of the UN Model Regulations pertaining to the 
design, construction, and inspection of UN pressure drums. PHMSA has 
reviewed this document as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and expects 
that its addition will facilitate the continued use of UN pressure 
drums with no degradation of safety.

     In paragraph (aa)(3), incorporate by reference the OECD 
Guidelines for the Testing of Chemicals ``Test No. 439: In Vitro Skin 
Irritation: Reconstructed Human Epidermis Test Method'' (2015). This 
Test Guideline (TG) provides an in vitro procedure that may be used for 
the hazard identification of irritant chemicals. PHMSA proposes to 
reference this test in Sec.  173.137, and to authorize the use of this 
test method in addition to those already referenced in that section. 
This test method is used to specifically exclude a material from 
classification as corrosive and to maintain alignment with the 22nd 
revised edition of the UN Model Regulations. This test method provides 
an in vitro procedure that may be used for the hazard identification of 
irritant chemicals (substances and mixtures). OECD test methods can be 
found in the OECD iLibrary available at https://www.oecd-ilibrary.org/.
     In paragraph (dd), incorporate by reference United Nations 
standards including:

--``The Recommendations on the Transport of Dangerous Goods--Model 
Regulations,'' 22nd revised edition (2021), Volumes I and II, in 
paragraph (dd)(1), which are referenced in Sec. Sec.  171.8; 171.12; 
172.202; 172.401; 172.407; 172.502; 172.519; 173.22; 173.24; 173.24b; 
173.40; 173.56; 173.192; 173.302b; 173.304b; 178.75; and 178.274. The 
Model Regulations provide framework provisions promoting uniform 
development of national and international regulations governing the 
transportation of hazardous materials by various modes of transport. At 
its tenth session on December 11, 2020, the UNSCOE on the Transport of 
Dangerous Goods adopted amendments to the UN Model Regulations on the 
Transport of Dangerous Goods concerning, inter alia, electric storage 
systems (including modification of the lithium battery mark and 
provisions for transport of assembled batteries not equipped with 
overcharge protection), requirements for the design, construction, 
inspection and testing of portable tanks with shells made of fiber 
reinforced plastics (FRP) materials, modified listings of dangerous 
goods; and additional harmonization with the IAEA Regulations for the 
Safe Transport of Radioactive Material. PHMSA participates in the 
development of the UN Model Regulations and has determined that the 
amendments adopted in the 22nd revised edition support the safe 
transport of hazardous materials and as such are appropriate for 
incorporation in the HMR. The 22nd revised edition of the UN Model 
Regulations is available online at: https://unece.org/transport/dangerous-goods/un-model-regulations-rev-22.
--``The Manual of Tests and Criteria, Amendment 1 to the Seventh 
revised edition'' (Rev.7/Amend.1) (2021), in paragraph (dd)(2)(ii), 
which is referenced in Sec. Sec.  171.24, 172.102; 173.21; 173.56; 
173.57; 173.58; 173.60; 173.115; 173.124; 173.125; 173.127; 173.128; 
173.137; 173.185; 173.220; 173.221; 173.224; 173.225; 173.232; part 
173, appendix H; 175.10; 176.905; and 178.274. The Manual of Tests and 
Criteria contains instruction for the classification of hazardous 
materials for purposes of transportation according to the UN Model 
Regulations. At its tenth session the Committee of Experts on the 
Transport of Dangerous Goods and on the Globally Harmonized System of 
Classification and Labelling of Chemicals adopted a set of amendments 
to the seventh revised edition of the Manual, which were circulated and 
collected in amendment 1 to the seventh revised edition. The new 
amendments adopted in December 2020 pertain to the transport of 
explosives, including alignment with revised Chapter 2.1 of the GHS, 
classification of self-reactive substances and polymerizing substances, 
and the assessment of the thermal stability of samples and temperature 
control assessment for transport of self-reactive substances and 
organic peroxides. PHMSA has reviewed and approved the amendments 
adopted in this document and further expects that their incorporation 
in the HMR will provide an additional level of safety. PHMSA proposes 
to incorporate by reference this document as a supplement, to be used 
in conjunction with the seventh revised edition (2019). The amendments 
to the manual can be accessed at https://unece.org/transport/dangerous-goods/rev7-files.
--``Globally Harmonized System of Classification and Labelling of 
Chemicals (GHS),'' ninth revised edition (2021) in paragraph (dd)(3), 
which is referenced in Sec.  172.401. The GHS standard provides a basic 
scheme to identify the hazards of substances and mixtures and to 
communicate these hazards. At its tenth session on December 11, 2020, 
the Committee of Experts on the Transport of Dangerous Goods and on the 
Globally Harmonized System of

[[Page 34575]]

Classification and Labelling of Chemicals adopted a set of amendments 
to the eighth revised edition of the GHS which include, inter alia: 
revisions to Chapter 2.1 (explosives) to better address their explosion 
hazard when they are not in their transport configuration; revisions to 
decision logics; revisions to classification and labelling summary 
tables in Annex 1; revisions and additional rationalization of 
precautionary statements; and updates of references to OECD test 
guidelines for the testing of chemicals in Annexes 9 and 10. PHMSA has 
reviewed and approved the amendments incorporated in this document and 
further expects that its incorporation in the HMR will provide an 
additional level of safety. The ninth revised edition of the GHS can be 
accessed at https://unece.org/transport/standards/transport/dangerous-goods/ghs-rev9-2021.
Section 171.12
    Section 171.12 prescribes requirements for shipments of hazardous 
materials in North America, including use of the Transport Canada (TC) 
Transportation of Dangerous Goods (TDG) Regulations. In rule HM-
215N,\10\ PHMSA amended the HMR to expand recognition of cylinders and 
pressure receptacles, and certificates of equivalency--Transport 
Canada's equivalent of a special permit--approved in accordance with 
the TDG Regulations. The goal of these amendments was to promote 
flexibility and permit the use of modern technology for the 
requalification and use of pressure receptacles, to expand the universe 
of pressure receptacles authorized for use in hazardous material 
transport, to reduce the need for special permits, and to facilitate 
cross-border transportation of these pressure receptacles. In 
accordance with Sec.  171.12(a)(4), when the provisions of the HMR 
require the use of either a DOT specification or a UN pressure 
receptacle for transport of a hazardous material, a packaging 
authorized by Transport Canada's TDG Regulations may be used only if it 
corresponds to the DOT specification or UN standard. HM-215N revised 
paragraph (a)(4)(iii) to include a table listing Canadian Railway 
Commission (CRC), Board of Transport Commissioners for Canada (BTC), 
Canadian Transport Commission (CTC) or Transport Canada (TC) 
specification cylinders, in accordance with the TDG Regulations, and in 
full conformance with the TDG Regulations, that correspond with a DOT 
specification cylinder.
---------------------------------------------------------------------------

    \10\ 82 FR 15796 (Mar. 30, 2017).
---------------------------------------------------------------------------

    However, there are currently no TC specification cylinders 
corresponding to DOT specification cylinders listed in the table for 
DOT-8 and DOT-8AL cylinders used to transport acetylene. During the 
development of HM-215N, PHMSA conducted a comparative analysis of DOT 
and TC cylinder specifications and only those TC cylinder 
specifications that corresponded directly to DOT cylinder 
specifications were included. The result was that PHMSA did not include 
TC-8WM and TC-8WAM specifications for the transport of acetylene in the 
table of corresponding cylinders at Sec.  171.12(a)(4)(iii). This 
omission was primarily due to concerns over differing solvent 
authorizations, calculations, and methods of construction for the 
design associated with the TC-8WM and TC-8WAM specifications. PHMSA 
conducted a second comparative analysis of DOT and TC cylinder 
specifications for transport of acetylene and concluded that the 
initial concerns were unwarranted. Therefore, PHMSA proposes to add TC-
8WM and TC-8WAM specifications to the table of corresponding DOT 
specifications in Sec.  171.12(a)(4)(iii) as comparable cylinders to 
DOT-8 and DOT-8AL, respectively.
    PHMSA's supplemental review indicates the differences between the 
TC and DOT specifications for transport of acetylene are minor and the 
standard for safety of transportation of acetylene in cylinders under 
the HMR is maintained. This proposal would allow for TC acetylene 
cylinders manufactured in Canada to be filled, used, and requalified 
(including rebuild, repair, reheat-treatment) in the United States, 
facilitating cross border movement of acetylene and eliminates the need 
for a special permit to allow transport of acetylene in these TC-8WM 
and TC-8AWM cylinders while maintaining an equivalent level of safety. 
Additionally, this proposal would provide reciprocity to Transport 
Canada's authorized use of DOT-8 and DOT-8AL cylinders for acetylene 
transport.
Section 171.23
    Section 171.23 outlines the requirements for specific materials and 
packagings transported under the ICAO Technical Instructions, IMDG 
Code, Transport Canada TDG Regulations, or the IAEA Regulations. It 
also includes authorized use, under specific conditions, of pi-marked 
pressure receptacles that comply with the Agreement Concerning the 
International Carriage of Dangerous Goods by Road (ADR), and the EU 
Directive 2010/35/EU,\11\ and marked with a pi ([pi]) symbol to denote 
such compliance for transport of hazardous materials. PHMSA proposes to 
amend the language in the provisions for pi-marked pressure receptacles 
in paragraph (a)(3) to clarify the scope of pressure receptacles 
authorized by this section. Pressure receptacles is a collective term 
that may be used to refer to many types of pressurized containers of 
various sizes, such as cylinders, tubes, pressure drums, closed 
cryogenic receptacles, metal hydride storage systems, bundles of 
cylinders or salvage pressure receptacles. When PHMSA adopted the 
provisions for pi-marked pressure receptacles,\12\ we did not intend to 
broadly apply the scope to all pressure receptacle types. Instead, 
PHMSA's intent was to apply the authorized use of pi-marked pressure 
receptacles domestically to only cylinders, as indicated in current 
paragraph (a)(3)(iii), which specifically references cylinders. Some of 
the pressure receptacles authorized in accordance with the ADR standard 
do not have an equivalent packaging authorized in the HMR, and some 
have large capacities, both of which give pause to PHMSA with respect 
to the hazardous materials authorized in these packagings. Therefore, 
PHMSA proposes to replace the words ``pressure receptacles'' in 
paragraph (a)(3) with ``cylinders with a water capacity not exceeding 
150 L,'' as defined in Sec.  171.8, to specify the scope of pi-marked 
pressure receptacles authorized under Sec.  171.23. PHMSA expects that 
this amendment will improve safety by providing additional clarity with 
regard to the scope of authorized use of pi-marked pressure receptacles 
for transport of hazardous material in the United States. PHMSA is 
aware of growing interest in the authorization for use of other pi-
marked pressure receptacles and PHMSA plans to address that issue in a 
future rulemaking.
---------------------------------------------------------------------------

    \11\ U.N. Econ. Comm'n for Europe, Transportation Division, 
Agreement Concerning the Int'l Carriage of Dangerous Goods by Road, 
110th Sess., ECE/TRANS/300, U.N. Sales No. E. 21. VIII. 1 (2020).
    \12\ 85 FR 75680 (Nov. 25, 2020).
---------------------------------------------------------------------------

Section 171.25
    Section 171.25 outlines additional requirements for the use of the 
IMDG Code in addition to those found in Sec.  171.22 and Sec.  171.23. 
As discussed above in Section IV. Amendments Not Being Considered for 
Adoption, specifically Issue #1, PHMSA is not proposing to adopt 
provisions for UN FRP portable tanks in the HMR.

[[Page 34576]]

However, to facilitate limited import and export of these tanks in 
international commerce, and to gain additional experience with their 
transport, PHMSA proposes to add a new paragraph Sec.  171.25(c)(5) 
that would prohibit the general transportation of UN FRP portable tanks 
designed and constructed in accordance with Chapter 6.10 of the IMDG 
Code within the United States, yet allow for the tanks to be 
transported within a single port area in the United States in 
accordance with the provisions of Sec.  171.25(d) covering the use of 
the IMDG Code in port areas. This action will maintain the safe 
transportation of hazardous material under the HMR while facilitating 
international commerce by permitting the import or export of hazardous 
materials in UN FRP portable tanks and limiting their use and movement 
within the confines of a single port area.

B. Part 172

Section 172.101 Hazardous Materials Table (HMT)
    The HMT summarizes terms and conditions governing transportation of 
listed hazardous materials under the HMR. For each entry, the HMT 
identifies information such as the PSN, UN identification number, and 
hazard class. The HMT specifies additional information or reference 
requirements in the HMR such as hazard communication, packaging, 
quantity limits aboard aircraft, and stowage of hazardous materials 
aboard vessels. PHMSA proposes several changes to the HMT as discussed 
below. For purposes of the Government Publishing Office's typesetting 
procedures, proposed changes to the HMT appear under three sections of 
the HMT: ``remove,'' ``add,'' and ``revise.'' Certain entries in the 
HMT, such as those with revisions to the PSNs, appear as a ``remove'' 
and ``add.'' Proposed amendments to the HMT include the following:
New HMT Entry
    PHMSA proposes to add new entry, ``UN3550, Cobalt dihydroxide 
powder, containing not less than 10% respirable particles, Division 
6.1, PG I'' to the HMT. Cobalt is a key strategic mineral used in 
various advanced medical and technical applications around the world, 
and it is essential to keep the global supply chains for this material 
open. This material has a 40-year history of safe global transport as 
``UN3077, Environmentally hazardous substance, solid, n.o.s., Class 9'' 
in different forms, including as crude material directly from mines, 
high moisture content paste, and very fine refined powders in flexible 
IBCs rated for PG III. However, recent testing required for compliance 
with the REACH Regulation in the European Union, and subsequent 
evaluation against the hazard classification criteria of the EU 
Classification, Labelling, and Packaging (CLP) Regulation resulted in a 
classification of Acute toxicity by inhalation Category 1, which is 
equivalent to the Division 6.1 hazard classification. As a result of 
this testing, it was determined that when this material is in fine 
powder form, it must no longer be transported as Class 9 miscellaneous 
hazard material. In powder form, cobalt dihydroxide powder must now be 
classified as a Division 6.1 toxic-by-inhalation solid material, for 
which a unique UN identification number and associated classification, 
hazard communication, and packing instructions does not currently exist 
in the HMT. This change in classification led to the development of the 
new UN identification number UN3550 and associated transportation 
requirements by the UNSCOE. To that end, the UNSCOE developed 
appropriate packaging provisions, including a special packaging 
condition, which permits the continued use of certain flexible IBCs. 
PHMSA notes that other forms of cobalt dihydroxide powder may continue 
to be classified and described as ``UN3077, Environmentally hazardous, 
solid, n.o.s., 9, PG III.'' Specifically, the UNSCOE addressed shipper 
concerns that flexible IBCs are not otherwise permitted for transport 
of Division 6.1 toxic solids, yet there is a 40-year record of safe 
transport of the refined material as UN3077 material in flexible IBCs, 
with no recorded accidents, incidents, or health issues. PHMSA proposes 
to also add a corresponding special provision (IP22) to indicate that 
the use of certain flexible IBCs is permitted for UN3550, which is 
discussed further in Sec.  172.102 of this Section-by-Section Review). 
The other packaging provisions for this cobalt dihydroxide powder are 
consistent with those for other Division 6.1 solid materials assigned 
PG I, such as ``UN3467, Organometallic compound, solid, toxic, n.o.s.'' 
An entry for UN3550 was also added in the 2023-2024 ICAO Technical 
Instructions and aligns with the proposed packaging requirements in 
this NPRM. PHMSA agrees with the UN provision to allow for the 
continued transport of this hazardous material in flexible IBCs, or in 
accordance with other special provisions and packaging requirements 
outlined in Part 173. The addition of this new HMT entry will maintain 
the HMR's safety standard for transportation of Division 6.1 solid 
materials.
HMT Corrections
    PHMSA proposes to make corrections to multiple HMT entries that 
were inadvertently modified in previous rulemakings. Specifically, for 
the PGII and PGIII entries for ``UN3129, Water-reactive liquid, 
corrosive, n.o.s'' and ``UN3148, Water-reactive liquid, n.o.s'', the 
references to exceptions in Sec.  173.151 in Column 8A were removed and 
replaced with the word ``None''. While there are no exceptions these 
materials when assigned to PGI, PHMSA did not intend to remove the 
exceptions for PGII and III materials. Additionally, for the PGIII 
entry for ``UN3148, Water-reactive liquid, n.o.s'', the ``G'' in Column 
1, which indicates that a technical name must be provided in 
association with the proper shipping name, was also inadvertently 
deleted. PHMSA expects that making these editorial corrections will 
prevent frustrations in shipping due to the inadvertent removal of the 
reference to authorized shipping exceptions and confusion regarding the 
required shipping description. PHMSA also proposes a correction to the 
entry ``UN0512, Detonators, electronic programmable for blasting''. In 
HM-215P, PHMSA added three new entries for electronic detonators to 
distinguish them from electric detonators, which have different 
functioning characteristics but similar regulatory provisions for their 
transport. PHMSA incorrectly assigned an obsolete special provision, 
Special Provision 103, which was removed from the HMR by final rule HM-
219C.\13\ UN0512 is comparable to the entry UN0255 and therefore should 
reflect the same special provision, Special Provision 148. Therefore, 
PHMSA proposes to remove the reference to Special Provision 103 in 
Column 7 for UN0512 and replace it with Special Provision 148 
consistent with the entry of UN0255. PHMSA expects that this correction 
will remove confusion surrounding additional provisions for these 
detonators. Lastly, PHMSA proposes a correction to the proper shipping 
name for UN3380, which should read ``Desensitized explosive, solid, 
n.o.s.''. In the previous HM-215 rulemaking, the word ``explosive'' was 
inadvertently made plural. This spelling is in conflict with a similar 
material on the HMT, ``UN3379. Desensitized explosive, liquid, n.o.s.'' 
and international regulations. Therefore, PHMSA expects that this 
correction will remove

[[Page 34577]]

confusion surrounding the proper shipping name for these materials.
---------------------------------------------------------------------------

    \13\ 85 FR 75680 (November 25, 2020).
---------------------------------------------------------------------------

    Lastly, PHMSA proposes to make a correction to the HMT entry for 
``UN1791, Hypochlorite Solutions''. In HM-215O, PHMSA added stowage 
codes 53 and 58--which require stowage ``separated from alkaline 
compounds'' and ``separated from cyanides,'' respectively--to Column 
10B of the HMT for several hazardous materials for consistency with 
changes included in Amendment 39-18 of the IMDG Code. These stowage 
codes were intended to be applied to several HMT entries to ensure 
proper segregation between acids and both amines and cyanides but 
should not have included UN1791. Therefore, PHMSA proposes to remove 
stowage codes 53 and 58 from Column 10B for this entry. PHMSA expects 
that this correction will remove the burden faced by shippers who have 
had to segregate hypochlorite solutions for compliance with the HMR, 
which is inconsistent with the requirements of the IMDG Code.
Column (2) Hazardous Materials Descriptions and Proper Shipping Names
    Section 172.101(c) describes column (2) of the HMT and the 
requirements for hazardous materials descriptions and PSNs. PHMSA 
proposes to consolidate two entries in the HMT that are currently 
listed under ``UN1169, Extracts, aromatic, liquid'' (PGII and PGIII) 
and ``UN1197, Extracts, flavoring, liquid'' (PGII and PGIII). 
Specifically, PHMSA proposes to remove the table entry for ``UN1169, 
Extracts, aromatic, liquid'' and modify the PSN associated with the 
table entry for UN1197 to reflect materials that have been historically 
transported separately under UN1169 and UN1197. The 22nd revised 
edition of the UN Model Regulations made these same changes, deleting 
UN1169 from the Dangerous Goods List and changing the PSN for UN1197 to 
``Extracts, liquid, for flavor or aroma'' to remove confusion 
associated with selection of the appropriate PSNs across the various 
languages of nations engaged in international shipments of the 
material. It became apparent that, whether for a flavor extract or 
aroma extract, the PSNs were often used interchangeably as there is no 
difference between the two with regard to classification, hazard 
communication, and packaging for transport. PHMSA agrees that the 
existence of two interchangeable UN numbers does not provide any 
additional value and, therefore, proposes to remove the table entry for 
UN1169 and modify the PSN for UN1197 to read ``Extracts, liquid, for 
flavor or aroma''. Additionally, PHMSA proposes to amend the text of 
paragraph (c)(12)(ii), which outlines requirements for generic or 
n.o.s. descriptions. The text of this paragraph provides an example 
using ``Extracts, flavoring, liquid.'' Therefore, PHMSA proposes to 
amend the wording of that example by replacing ``Extracts, flavoring, 
liquid'' with ``Extracts, liquid, for flavor or aroma'' to correspond 
to the amended PSN for UN1197. This proposed action maintains the 
current level of safety for transportation of liquid extracts.
Column (3) Hazard Class or Division
    Section 172.101(d) describes column (3) of the HMT, which 
designates the hazard class or division corresponding to the PSN of 
that entry. Consistent with changes adopted in the 22nd revised edition 
of the UN Model Regulations, PHMSA proposes to change the primary 
hazard classification for the entry ``UN1891, Ethyl Bromide,'' from a 
toxic liquid of Division 6.1 to a Class 3 flammable liquid. This change 
in classification is consistent with the change adopted in the 2023-
2024 ICAO Technical Instructions as well as the UN Model Regulations 
and is based on new test data indicating that the flash point and 
boiling point of ethyl bromide has a core flammability hazard according 
to the Class 3 classification criteria of the ICAO Technical 
Instructions. More specifically, different data sources showed that its 
flash point of -20 [deg]C (-4 [deg]F) and its boiling point of 38 
[deg]C (100.4 [deg]F) meet the criteria for assignment as a Class 3 at 
the PG II level--the criteria of which is having a flash point <23 
[deg]C and boiling point >35 [deg]C. Additionally, rather than 
classifying ethyl bromide solely as a Class 3 flammable liquid, it was 
determined that the Division 6.1 hazard still applies and should remain 
assigned as a subsidiary hazard. This is consistent with the HMR 
precedence of the hazard table in Sec.  173.2a that instructs for a 
material that meets criteria for classification as both Class 3 and 
Division 6.1 (except for when a material meets the PG I poison-by-
inhalation criteria), the flammability hazard takes precedence and is 
the primary hazard. These changes in hazard class and associated 
packaging requirements were adopted to ensure that the hazards of ethyl 
bromide are accurately communicated and appropriately packaged. PHMSA 
reviewed these findings and agrees that it is appropriate to classify 
ethyl bromide as a flammable liquid, with a subsidiary Division 6.1 
hazard. Because of this change in hazard class, additional conforming 
changes to the HMT entry for ethyl bromide are required in column (6), 
as discussed below. Additionally, PHMSA expects that clearly 
identifying the flammability hazard posed by this material will improve 
safety by ensuring that the material is handled appropriately before 
and during transport.
Column (6) Label Codes
    Section 172.101(g) describes column (6) of the HMT, which contains 
label codes representing the hazard warning labels required for a 
package filled with a material conforming to the associated hazard 
class and proper shipping name, unless the package is otherwise 
excepted from labeling. The first code is indicative of the primary 
hazard of the material. Additional label codes are indicative of 
subsidiary hazards. As discussed above, PHMSA proposes to modify the 
primary hazard class for ``UN1891, Ethyl bromide'' to Class 3. 
Consistent with this change, PHMSA proposes to assign Class 3 as the 
primary hazard label and Division 6.1 as a subsidiary hazard label. 
Consequently, PHMSA proposes to amend column (6) of the HMT for this 
entry to reflect the warning labels required for the transport of this 
hazardous material. PHMSA expects that this proposed change will 
improve safety by clearly communicating the transportation hazards of 
this material.
Column (7) Special Provisions
    Section 172.101(h) describes column (7) of the HMT, which assigns 
special provisions for each HMT entry. Section 172.102 provides for the 
meaning and requirements of the special provisions assigned to entries 
in the HMT. The proposed revisions to column (7) of certain entries in 
the HMT are discussed below.
Special Provision 396
    PHMSA proposes to add a new special provision, Special Provision 
396, and assigning it to ``UN3538, Articles containing non-flammable, 
non-toxic gas, n.o.s.'' For additional information, see Sec.  172.102 
of the Section-by-Section Review.
Special Provision 398
    PHMSA proposes to assign a newly added special provision, Special 
Provision 398, which pertains to the potential classification of 
butylene and butylene mixtures as UN1012. This special provision 
clarifies that butylene mixtures and certain butylene isomers may be 
assigned to UN1012, while specifically excluding isobutylene from this 
UN classification. For additional

[[Page 34578]]

information, see Sec.  172.102 of the Section-by-Section Review.
Special Provisions A4 and A5
    PHMSA proposes to assign Special Provision A4 to the entry 
``UN2922, Corrosive liquid, toxic, n.o.s.'' and Special Provision A5 to 
the entry ``UN2923, Corrosive solid, toxic, n.o.s.''. Special 
Provisions A4 and A5 address liquids and solids in PG I that also pose 
an inhalation toxicity hazard by limiting or prohibiting their 
transportation on aircraft. In principle, all liquids or solids that 
have an inhalation toxicity hazard, and assigned PG I, should be 
subject to one of the two special provisions, as appropriate. However, 
UN2922 and UN2923 are assigned Class 8 as the primary hazard and 
Division 6.1 as a subsidiary hazard because of classification 
guidelines which require hazardous materials that meet the criteria of 
Class 8 and that have an inhalation toxicity of dusts and mists (LC50) 
in the range of PG I, but toxicity through oral ingestion or dermal 
contact only in the range of PG III or less, must be assigned to Class 
8 as the primary hazard rather than Division 6.1. In reviewing these 
provisions, the ICAO Dangerous Goods Panel (DGP) determined that 
additional restrictions should be implemented for these hazardous 
materials as the corrosive classification assigned to UN2922 and UN2923 
does not negate the inhalation toxicity hazard. Because of the 
inhalation hazard posed by these materials, the 2023-2024 ICAO 
Technical Instructions included an amendment to impose quantity limits 
for transportation of these materials by air. PHMSA agrees with this 
determination and therefore proposes to assign Special Provision A4 to 
UN2922, which prohibits it from transport on passenger and cargo 
aircraft. PHMSA also proposes to assign Special Provision A5 to UN2923, 
which prohibits this material on passenger aircraft and limits the 
amount that may be transported on cargo aircraft. PHMSA expects that 
correcting this conflict will improve safety by prohibiting corrosive 
materials that also pose inhalation hazards on passenger aircraft and 
limiting their transport on cargo aircraft.
Special Provisions A224 and A225
    PHMSA proposes to add two new air special provisions, A224 and 
A225, and assign them to HMT entries ``UN3548, Articles containing 
miscellaneous dangerous goods, n.o.s.'' and ``UN3538, Articles 
containing non-flammable, non-toxic gas, n.o.s.,'' respectively. These 
special provisions would allow for transport on both passenger aircraft 
and cargo aircraft under certain conditions. For additional 
information, see 172.102 of the Section-by-Section Review. Also, see 
Sec.  172.102 of the Section-By-Section Review below for a detailed 
discussion of the special provision amendments addressed in this NPRM.
Column (8) Packaging
    Section 172.101(i) explains the purpose of column (8) in the HMT. 
Columns (8A), (8B), and (8C) specify the applicable sections for 
exceptions, non-bulk packaging requirements, and bulk packaging 
requirements, respectively. Columns (8A), (8B), and (8C) are completed 
in a manner which indicates that ``Sec.  173.'' precedes the designated 
numerical entry. Column (8A) contains exceptions from some of the 
requirements of this subchapter. The referenced exceptions are in 
addition to those specified in subpart A of part 173 and elsewhere in 
subchapter C. The word ``None'' in this column means no packaging 
exceptions are authorized, except as may be provided by special 
provisions in column (7). For example, the entry ``151'' in column 
(8A), associated with the proper shipping name ``Nitrocellulose with 
water,'' indicates that, for this material, packaging exceptions are 
provided in Sec.  173.151 of this subchapter.
    PHMSA proposes to remove references to Sec.  173.151, which provide 
exceptions for Class 4 hazardous materials, in column (8A), and add the 
word ``None'' for three solid desensitized explosive entries: ``UN2555, 
Nitrocellulose with water with not less than 25 percent water by 
mass''; ``UN2556, Nitrocellulose with alcohol with not less than 25 
percent alcohol by mass, and with not more than 12.6 percent nitrogen, 
by dry mass''; and ``UN2557, Nitrocellulose, with not more than 12.6 
percent nitrogen, by dry mass mixture with or without plasticizer, with 
or without pigment.'' These changes would remove the applicability of 
the limited quantity exceptions for these hazardous materials to 
correct an inconsistency regarding solid desensitized explosives. 
Consistent with the UN Model Regulations, PHMSA has not authorized 
limited quantity packaging exceptions for 30 other solid desensitized 
explosives.\14\ Solid desensitized explosives are explosive substances 
which are wetted with water or alcohols or are diluted with other 
substances to form a homogeneous solid mixture to suppress their 
explosive properties. Like PG I materials, solid desensitized 
explosives in PG II are specifically prohibited from transport under 
the limited quantity provisions in the UN Model Regulations. However, 
this inconsistency was identified with respect to air transport by the 
ICAO DGP (Dangerous Goods Panel), resulting in a similar amendment in 
the 2023-2024 ICAO Technical Instructions. In this NPRM, PHMSA also 
proposes related editorial amendments in Sec.  173.27, general 
requirements for transportation by aircraft (see additional discussion 
in Sec.  173.27 of Section-by-Section Review). PHMSA expects that 
correcting this oversight to require that these nitrocellulose mixtures 
be transported in accordance with all requirements of the HMR, rather 
than permitting the use of the limited quantity exceptions in Sec.  
173.151, will not only add an additional level of safety, but that it 
will also facilitate the transport of these materials by streamlining 
packaging and hazard communication requirements to be consistent with 
requirements for similar materials and with international regulations.
---------------------------------------------------------------------------

    \14\ UN1310, UN1320, UN1321, UN1322, UN1336, UN1337, UN1344, 
UN1347, UN1348, UN1349, UN1354, UN1355, UN1356, UN1357, UN1517, 
UN1571, UN2555, UN2556, UN2557, UN2852, UN2907, UN3317, UN3319, 
UN3344, UN3364, UN3365, UN3366, UN3367, UN3368, UN3369, UN3370, 
UN3376, UN3380, and UN3474.UN1517, UN1571, UN2555, UN2556, UN2557, 
UN2852, UN2907, UN3317, UN3319, UN3344, UN3364, UN3365, UN3366, 
UN3367, UN3368, UN3369, UN3370, UN3376, UN3380, and UN3474.
---------------------------------------------------------------------------

Column (9) Quantity Limitations
    Section 172.101(j) explains the purpose of column (9) in the HMT. 
Column (9) specifies quantity limitations for packages transported by 
air and rail. Column (9) is divided into two columns: column (9A) 
provides quantity limits for passenger aircraft/rail, and column (9B) 
provides quantity limits for cargo aircraft.
    Consistent with changes adopted in the 2023-2024 edition of the 
ICAO Technical Instructions, PHMSA proposes to amend the quantity 
limitations for UN 1891, Ethyl bromide, when transported by passenger 
aircraft. Previously, the maximum net quantity per package for 
passenger aircraft was 5 L on the Dangerous Goods List of the ICAO 
Technical Instructions; this same quantity limit is currently in place 
for passenger aircraft, as indicated in column (9A) of the HMT. As a 
result of the reclassification of UN1891 as a Class 3 flammable liquid, 
the permitted quantity was reduced in the ICAO Technical Instructions 
to 1L per packaging. This change is in line with the quantity limits 
for many other Class 3 materials. PHMSA proposes to make a 
corresponding change for passenger

[[Page 34579]]

aircraft limits in column (9A). With regard to cargo aircraft, no 
changes to the 60 L maximum net quantity were made in the ICAO 
Technical Instructions, as that limit is the same for Class 3 and 
Division 6.1 materials. PHMSA expects that this change will provide an 
additional level of safety commensurate to the newly recognized 
flammability hazard posed by this material.
    PHMSA also proposes to modify the packaging limits aboard cargo 
aircraft for three battery entries: ``UN2794, Batteries, wet, filled 
with acid, electric storage''; ``UN2795, Batteries, wet, filled with 
alkali, electric storage''; and ``UN3292, Batteries, containing 
sodium.'' Specifically, these changes would limit the quantity per 
packaging to 400 kg, as there is currently no limit for these items. 
Typically, these articles must be packed in UN specification 
packagings, and 400 kg is the maximum quantity permitted in such 
packagings. These proposed changes are consistent with changes made in 
the 2023-2024 ICAO Technical Instructions, which were made as a 
correction to an inconsistency between the ICAO Technical Instructions 
and the UN Model Regulations. Therefore, in column (9B) of the HMT, the 
words ``no limit'' will be replaced by 400 kg. PHMSA expects that this 
change will streamline packaging requirements by providing packaging 
limits for similar items in similar packagings, consistent with 
analogous international regulations. This streamlining will also 
increase safety by increasing clarity on the packaging limits for these 
similar items.
Section 172.102 Special Provisions
    Section 172.102 lists special provisions applicable to the 
transportation of specific hazardous materials. Special provisions 
contain various provisions including packaging requirements, 
prohibitions, and exceptions applicable to particular quantities or 
forms of hazardous materials. PHMSA proposes the following revisions to 
the special provisions in this section:
Special Provision 78
    Special Provision 78 currently states that ``UN1002, Air, 
compressed'' may not be used to describe compressed air which contains 
more than 23.5% oxygen. It also stipulates that compressed air 
containing more than 23.5% oxygen must be shipped using the description 
``UN3156, Compressed gas, oxidizing, n.o.s.'' which has a Class 5 
subsidiary hazard classification. PHMSA proposes to amend Special 
Provision 78, in order to provide additional clarity with regard to the 
permitted use of the proper shipping description UN1002. In an effort 
to address specific mixtures of nitrogen and oxygen that are 
commercially called ``synthetic air,'' the 22nd revised edition of the 
UN Model Regulations includes a new special provision that was intended 
to clarify that ``synthetic air'' may be transported under UN1002, 
provided that it does not contain more than 23.5% oxygen. ``Synthetic 
air'' is typically a mixture containing up to 23.5% oxygen with the 
balance being nitrogen. This mixture is used in a variety of 
applications, including medical and non-medical, and may be used when 
ambient air is not sufficient due to the presence of contaminants. This 
new special provision specifies that mixtures of nitrogen and oxygen 
containing not less than 19.5% and not more than 23.5% oxygen by volume 
may be transported under UN1002 when no other oxidizing gases are 
present. It also states that a Division 5.1 subsidiary hazard label is 
not required for any concentrations within this limit. While this 
language is not drastically different than the current language in the 
HMR, PHMSA expects that rewording Special Provision 78 to include the 
19.5% lower bound for oxygen and the note regarding the use of the 
Division 5.1 subsidiary hazard label will improve safety by providing 
clearer and more useful instructions for shippers of compressed 
synthetic or ambient air.
Special Provision 156
    PHMSA proposes to amend Special Provision 156 to require that, when 
transported by air, a shipping paper, such as an air waybill 
accompanying the shipment must indicate that the package containing 
asbestos is not restricted for shipment. Currently, this special 
provision excepts asbestos from the requirements of 49 CFR Subchapter C 
when it is immersed or fixed in a natural or artificial binder--such as 
cement, plastics, asphalt, resins, or mineral ore--in such a way that 
no escape of hazardous quantities of respirable asbestos fibers can 
occur. It was noted that confusion over whether a shipment was or was 
not excepted from the regulations had led to delays and frustrated 
shipments. The 2023-2024 ICAO Technical Instructions amended a similar 
special provision to assist in providing evidence of compliance with 
its requirements. PHMSA's proposed amendment to Special Provision 156 
would require that, when transported by air, packages or shipping 
documentation be marked to indicate that the package containing 
asbestos is not restricted for shipment. PHMSA expects that this 
requirement will facilitate the safe shipment of asbestos by preventing 
them from being mistaken as fully regulated hazardous materials.
Special Provision 387
    Special Provision 387 provides shippers of polymerizing substances 
with information regarding stabilization requirements for their 
shipments. As discussed below, in an earlier rulemaking, PHMSA placed 
sunset dates on the HMR provisions concerning transport provisions for 
polymerizing substances to allow time for the completion of research on 
various topics concerning their transport and to gather and review 
empirical evidence concerning the appropriate transport provisions for 
polymerizing substances. In line with other amendments proposed in this 
NPRM for the transport of polymerizing substances, PHMSA is proposing 
to amend Special Provision 387 to remove the sunset date of January 2, 
2023. The result of this proposed amendment is that the existing 
stabilization requirements noted in this special provision remain and 
the sunset date is removed. See 173.21 of the Section-by-Section Review 
for the full discussion of changes pertaining to polymerizing 
substances.
Special Provision 396
    PHMSA proposes to add a new special provision, Special Provision 
396, and assign it to ``UN3538, Articles containing non-flammable, non-
toxic gas, n.o.s,'' to authorize the transport of large and robust 
articles (e.g., transformers) that include cylinders containing UN1066 
``Nitrogen''; UN1956 ``Compressed gas N.O.S.''; or UN1002 ``Air, 
compressed'' with the valves open to allow low quantities of gas to be 
constantly supplied through a pressure regulator from a gas cylinder 
connected to the transformer. Similar provisions were added in the 22nd 
revised edition of the UN Model Regulations and Amendment 41-22 of the 
IMDG Code to address shipments of transformers, which are typically 
pressurized with nitrogen or with air but are not gas tight. Prior to 
2020, transformers were transported as ``UN 3363, Dangerous Goods in 
Machinery/Apparatus''; however, the packing provisions for UN3363 
imposed quantity limits requiring multiple approvals from competent 
authorities as specified in Special Provision 136 in the HMR (SP 301 in 
the UN Model Regulations). Following more recent amendments to

[[Page 34580]]

the UN Model Regulations, these transformers were eligible for 
transport under UN 3538, the provisions which allow these transformers 
to be transported unpackaged, do not explicitly require the transformer 
to be gas-tight, but instead require the valves to be closed during 
transport. To obviate the need for an approval each time such 
transformers are transported, a new special provision was added to the 
22nd revised edition of UN Model Regulations because these transformers 
only emit small quantities of nitrogen or synthetic air, which are 
neither flammable, toxic, corrosive, nor oxidizing. PHMSA proposes 
several safety controls in shipments of this type that are largely 
consistent with the provisions adopted in the UN Model Regulations and 
the IMDG Code. These proposed controls include requiring that cylinders 
be connected to the article through pressure regulators and have fixed 
piping to keep the pressure below 35 kPa (0.35) bar; the cylinders must 
be secured to prevent shifting; the cylinders and other components must 
be protected from damage and impacts during transport; the shipping 
paper must include a reference to shipping under this special 
provision; and if placed inside a cargo transport unit (CTU), the CTU 
must be well ventilated. PHMSA notes that these international 
regulations require marking the CTU with the asphyxiation warning mark 
for CTUs. The HMR has not adopted this mark and is not proposing to do 
so at this time. PHMSA is not proposing this mark because it views the 
additional controls, specifically, the indication on the shipping 
paper, as well as other operational controls noted in the proposed 
special provision, as providing sufficient warning to those in the 
transport chain of the dangers present and mitigation of potential 
hazards. PHMSA expects that the addition of this special provision will 
facilitate the transport of this specialized machinery without imposing 
excessive manufacturing requirements to ensure gas tightness to prevent 
the release of relatively innocuous gases during transport.
Special Provision 398
    PHMSA proposes to add Special Provision 398, pertaining to the 
classification of hazardous materials under UN1012, Butylene. This new 
special provision would clarify that butylene mixtures and certain 
butylene isomers may be assigned to UN1012, while specifically 
excluding UN1055, Isobutylene from this UN classification. Butylene, 
also known as butene, includes four different isomers, corresponding to 
one general chemical formula, C4H8. One of these isomers is 
isobutylene, which, while similar to the other three isomers, has been 
assigned a separate UN number, UN1055, which has its own set of 
packaging provisions. To avoid ``UN1055, Isobutylene'' being classified 
and transported under UN1012, this amendment would facilitate 
consistent and proper classification of this group of hazardous 
materials. This clarification for UN1012, Butylene, was added in the 
22nd revised edition of the UN Model Regulations for consistency with 
European regulations, which made similar changes to avoid ``UN1055, 
Isobutylene'' being classified and transported under UN1012. PHMSA 
proposes to add this clarifying special provision with the expectation 
that it will facilitate consistent and proper classification of this 
group of hazardous materials.
Special Provision 421
    Special Provision 421 is assigned to the four polymerizing 
substance entries in the HMT. Currently this special provision notes 
that these entries will no longer be effective on January 2, 2023, 
unless extended or terminated prior to this date. As discussed in the 
``Executive Summary'' section of this rulemaking, PHMSA had placed 
sunset dates on the HMR provisions concerning transport provisions for 
polymerizing substances to allow time for the completion of research on 
various topics concerning their transport and to gather and review 
empirical evidence concerning the appropriate transport provisions for 
polymerizing substances. As we have completed this review, we are 
proposing to delete Special Provision 421 and to maintain the existing 
polymerizing substance HMT entries.
Special Provision 441
    PHMSA proposes to add a new Special Provision 441, assigning it to 
``UN1045, Fluorine, compressed.'' This new special provision would 
specifically address gas mixtures containing fluorine and inert gases 
in UN pressure receptacles in accordance with changes adopted in the 
22nd revised edition of the UN Model Regulations. Specifically, this 
change would provide latitude with regard to the maximum allowable 
working pressure when fluorine is a part of a mixture, which contains 
less reactive gases, such as nitrogen, when the mixture is transported 
in UN pressure receptacles. As a strongly oxidizing gas, pure fluorine 
requires specific safety measures because it reacts spontaneously with 
many organic materials and metals. Additionally, because of its 
reactive properties, the UN Model Regulations limit the maximum 
allowable working pressure for pure fluorine in cylinders to 30 bar and 
a minimum test pressure of 200 bar is also required. However, prior to 
changes adopted in the 22nd revised edition of the UN Model 
Regulations, there was no guidance on the maximum allowable working 
pressure and minimum test pressure for mixtures of gases which contain 
fluorine. Commercially, these mixtures are often placed on the market 
and used in concentrations, which may include as little as one percent 
fluorine combined with noble gases, or ten to twenty percent fluorine 
mixed with nitrogen. Due to the lack of specific provisions addressing 
fluorine gas mixtures, such mixtures containing relatively 
inconsequential amounts of fluorine were subject to the same 
requirements (restrictive maximum allowable working pressures) as pure 
fluorine. Given that fluorine, in a mixture with inert gases or 
nitrogen, is less reactive towards materials than pure fluorine, the 
UNSCOE determined that gas mixtures containing less than 35% fluorine 
by volume should no longer be treated like pure fluorine and may use a 
higher maximum allowable working pressure. The new packing provision 
added in the 22nd revised edition of the UN Model Regulations allows 
for pressure receptacles containing mixtures of fluorine and inert 
gases (including nitrogen) to have higher working pressures by allowing 
for consideration of the partial pressures exerted by the other 
constituents in the mixture, rather than limiting the pressure in the 
receptacle based on fluorine alone. Specifically, the provision permits 
mixtures of fluorine and nitrogen with a fluorine concentration below 
35% by volume to be filled in pressure receptacles up to a maximum 
allowable working pressure for which the partial pressure of fluorine 
does not exceed 31 bar absolute. Additionally, for mixtures of true 
inert gases and fluorine, where the concentration of fluorine is below 
35% by volume, pressure receptacles may be filled up to a maximum 
allowable working pressure for which the partial pressure of fluorine 
does not exceed 31 bar absolute, provided that when calculating the 
partial pressure, the coefficient of nitrogen equivalency is determined 
and accounted for in accordance with ISO 10156:2017. Finally, the newly 
added provision for these two types of gas mixtures limits the working 
pressure to 200 bar or less

[[Page 34581]]

and requires that the minimum test pressure of pressure receptacles for 
these mixtures equals 1.5 times the working pressure or 200 bar, with 
the greater value to be applied. While PHMSA is not adding similar 
provisions for this type of mixture in DOT specification cylinders in 
this rulemaking, PHMSA has evaluated the rationale and the methods for 
determining the pressure limits in UN pressure receptacles and finds 
that they provide an equivalent level of safety. For this reason, PHMSA 
proposes to adopt the packing instruction as drafted in the UN Model 
Regulations as a new special provision for UN1045.
Special Provision A54
    Special Provision A54 specifies that, irrespective of the quantity 
limits in column (9B) of the Sec.  172.101 table, a lithium battery, 
including a lithium battery packed with, or contained in, equipment 
that otherwise meets the applicable requirements of Sec.  173.185, may 
have a mass exceeding 35 kg, if approved by the Associate Administrator 
prior to shipment. PHMSA proposes to amend this special provision to 
require that, when this special provision is used, the special 
provision number must be indicated on the shipping paper. PHMSA expects 
that this amendment will enhance safety by improving the communication 
of potential hazards, as without such indication, the need for shipment 
acceptance staff to check and ensure a copy of the approval 
accompanying the shipment can potentially be missed.
Special Provisions A224 and A225
    The 2023-2024 ICAO Technical Instructions added two new special 
provisions permitting the transport of articles containing hazardous 
materials aboard passenger and cargo aircraft. Currently these articles 
are forbidden from transport on passenger and cargo aircraft, as 
specified in column (9) of the HMT. However, the ICAO DGP developed 
these packaging provisions, which include provisions that ensure 
appropriate gas containment during transport. The aim of these special 
provisions was to facilitate the transport of large articles containing 
environmentally hazardous substances (such as aircraft landing gear 
struts filled with hydraulic fluid) and large articles containing a 
non-flammable, non-toxic gas (such as new types of magnetic resonance 
imaging (MRI) scanners which often contain compressed helium as well as 
lithium cells or batteries). These amendments were adopted in the 2022-
2023 ICAO Technical Instructions and PHMSA proposes to mirror these 
provisions by adding two new air-specific special provisions, A224 and 
A225, and assigning them to HMT entries ``UN3548, Articles containing 
miscellaneous dangerous goods, n.o.s.'' and ``UN 3538, Articles 
containing non-flammable, non-toxic gas, n.o.s.'' respectively.
    These special provisions would allow for the transport of large 
articles containing a non-flammable, non-toxic gas or environmentally 
hazardous substances on both passenger aircraft and cargo aircraft only 
under certain conditions. Specifically, under Special Provision A224, 
``UN3548, Articles containing miscellaneous dangerous goods, n.o.s.'' 
would be permitted on passenger and cargo aircraft, provided that the 
only dangerous goods in the article are environmentally hazardous 
substances with or without lithium cells or batteries that comply with 
Sec.  173.185(c). Similarly, under Special Provision A225, ``UN3538, 
Articles containing non-flammable, non-toxic gas, n.o.s.'' would be 
permitted aboard passenger and cargo aircraft, provided that the 
article contains only a Division 2.2 gas that does not have a 
subsidiary hazard but excluding refrigerated liquefied gases and other 
gases forbidden for transport on passenger aircraft with or without 
lithium cells or batteries that comply with Sec.  173.185(c). In 
addition to containing only the permitted hazardous materials, the 
special provision would also require that shippers comply with 
additional packaging requirements, specified in Sec.  173.232, and that 
the special provision be indicated on shipping documentation.
    The ICAO DGP agreed that these provisions were appropriate given 
that environmentally hazardous substances pose a very low hazard in air 
and that non-flammable, non-toxic gases without subsidiary hazard are 
already allowed on both passenger and cargo aircraft as well as certain 
other articles containing similar gases. PHMSA agrees and expects that, 
in addition to aligning the HMR with recent changes added to the 2023-
2024 ICAO Technical Instructions, the addition of these provisions will 
facilitate the transport of these materials by air while maintaining 
the current level of safety for air transport of certain hazardous 
materials.
IP Codes
    IP Codes are special provisions that are assigned to specific 
commodities, applicable when that commodity is transported in IBCs. 
Table 2 in Sec.  172.102 specifies the requirements corresponding to 
the IP Code indicated in column (7) of the HMT. In this NPRM, PHMSA 
proposes to amend the text of IP15 and to add a new IP Code, IP22.
IP15
    PHMSA proposes to amend the text of IP15 to clarify language 
pertaining to the authorized period of use of composite IBCs. 
Currently, IP15 states that for IBCs containing UN2031 with more than 
55% nitric acid, rigid plastic IBCs and composite IBCs that have a 
rigid plastic inner receptacle are authorized for two years from the 
date of IBC manufacture. A change to a corresponding special provision 
was adopted in the 22nd revised edition of the UN Model Regulations to 
make clear that the authorized two-year period of use specifically 
refers to the duration of use of the inner receptacle of composite IBCs 
and not to the outer framework. The intent of this requirement is to 
limit the inner receptacle for composite IBCs to the two-year period of 
use when used for this specific corrosive material, rather than 
requiring that the outer framework be inspected as often. The entire 
composite IBC remains subject to the five-year inspection interval, 
prescribed in Sec.  180.352. This change in the UN Model Regulations 
was in response to mistranslations of the UN Model Regulations, which 
led to inconsistent maintenance of composite IBCs. While PHMSA is not 
aware of any issues surrounding the language in IP15, PHMSA expects 
that making this editorial change will ensure that international users 
are not confused by the text of the HMR, and this clarification will 
enhance safe transport of hazardous materials in such IBCs.
IP22
    As discussed earlier, PHMSA proposes to add a new IP code, IP22, 
for the new entry ``UN 3550, Cobalt dihydroxide powder, containing not 
less than 10% respirable particles.'' This special provision would 
authorize the transport of Cobalt dihydroxide powder, a Division 6.1 
solid, in flexible IBCs that are equipped with siftproof liners that 
would prevent any egress of dust during transport. This hazardous 
material was recently classified as a solid with a toxic-by-inhalation 
hazard. Prior to this Division 6.1 classification, cobalt dihydroxide 
had been transported as ``UN3077, Environmentally hazardous substance, 
solid, n.o.s., Class 9'' in unlined flexible IBCs. However, this 
reclassification posed a problem for shippers because flexible IBCs are 
not authorized for Division 6.1 toxic solids. In response to the recent 
EU GHS changes, many shippers stopped using

[[Page 34582]]

unlined flexible IBCs and began using lined 13H3 or 13H4 flexible IBCs 
to prevent the release of dust.\15\ Additionally, the industry also 
developed a new design type flexible IBC with an improved liner to 
prevent egress of dust. This new design type 13H3 flexible IBC has been 
tested and approved to PG I by international competent authorities. 
Consequently, to address the packaging problem shippers faced as a 
result of new classification criteria, the UNSCOE created a special 
provision that would allow this material to be transported in lined 
siftproof packagings. This decision was based on the forty-year record 
of safe transport in this material in PG III packagings, as well as the 
additional level of sift-proofness provided by the new design track 
record of the new siftproof packagings. PHMSA agrees with the UNSCOE's 
determination that siftproof flexible IBCs are appropriate packagings 
for this material and expects that this special provision will avoid 
unnecessary disruptions in the transport of this essential raw material 
while still ensuring safe transport of this material. The lack of a UN 
entry for this specific combination of physical and hazardous 
attributes--solid and toxic-by-inhalation--led to the development of 
this new UN entry by the UNSCOE. More specifically, UN3550 was created 
for cobalt dihydroxide to resolve the packaging and transport problem 
faced by shippers because of the new Division 6.1 classification. 
Consequently, based on the record of safe transport by multi-modal 
means in flexible IBCs, with no recorded accidents, incidents, or 
health issues as UN3077, the UNSCOE's resolution of this packaging 
conflict was to develop a new UN number, assigning appropriate packing 
provisions and creating a special packaging condition which permits the 
use of flexible IBCs.
---------------------------------------------------------------------------

    \15\ https://unece.org/DAM/trans/doc/2019/dgac10c3/UN-SCETDG-56-INF19e.pdf.
---------------------------------------------------------------------------

C. Part 173

Section 173.4b
    Section 173.4b specifies the hazard criteria and packaging 
requirements to qualify for the de minimis exception--i.e., exceptions 
from certain HMR requirements for very minor amounts of hazardous 
material. For non-infectious biological specimens that contain minor 
amounts of preservatives that are a hazardous material, PHMSA proposes 
to add a reference to formaldehyde solution in paragraphs (b)(1)(i) and 
(b)(1)(ii) to clarify that the conditions for packing of the specimens 
applies to formaldehyde solution too. Currently, paragraph (b) excepts 
non-infectious biological specimens, such as those of mammals, birds, 
amphibians, reptiles, fish, insects, and other invertebrates, 
containing small quantities of chemical preservatives like ethanol or 
formaldehyde solution from the HMR, provided certain conditions are 
met. For example, paragraph (b)(1) provides instruction for when 
alcohol or an alcohol solution is used, such as when a specimen is 
placed in a plastic bag, that any free liquid in the bag must not 
exceed 30 mL. The ICAO Technical Instructions include a similar 
instruction, yet during a review of the ICAO Technical Instructions, 
the ICAO DGP noted that the exception does not address when 
formaldehyde solutions are used as preservatives for specimens; thus, 
there was no specified limit on the amount of free liquid formaldehyde 
solution that may be in a packaging. Consequently, the 2023-2024 ICAO 
Technical Instructions include an amendment to the de minimis 
provisions to specify limits for formaldehyde solutions. PHMSA agrees 
with this clarifying amendment and expects that adopting a similar 
change will enhance safety by removing uncertainty about whether the 
quantity limits also apply formaldehyde solutions.
Section 173.21
    Section 173.21 describes situations in which offering for transport 
or transportation of certain materials or packages is forbidden. 
Examples of such forbidden shipments include materials designated as 
``Forbidden'' in Column (3) of the HMT; electrical devices that are 
likely to generate sparks and/or a dangerous amount of heat; and 
materials that are likely to decompose or polymerize and generate 
dangerous quantities of heat or gas during decomposition or 
polymerization. This last group of materials is addressed in paragraph 
(f) of this section, which outlines the conditions under which 
materials which are likely to decompose or polymerize unless stabilized 
or inhibited in some manner (e.g., with temperature controls or 
chemical stabilization) are authorized for transport.
    PHMSA proposes to lower the temperature threshold at which 
transport of certain materials in portable tanks require temperature 
control. Specifically, this amendment would lower this threshold 
temperature for a material which is likely to decompose with a self-
accelerated decomposition temperature (SADT) or polymerize with a self-
accelerated polymerization temperature (SAPT) from 50 [deg]C (122 
[deg]F) to 45 [deg]C (113 [deg]F) when transported in portable tanks. 
This means that if adopted, portable tanks containing materials likely 
to decompose or polymerize at temperatures greater than 45 [deg]C will 
not be required to be stabilized or inhibited by temperature control 
and otherwise be forbidden from transport. In an earlier rulemaking, 
HM-215N, PHMSA gave notice that at that time, it would not adopt 
reductions in temperature thresholds for shipments in portable tanks 
and maintained a 50 [deg]C (122 [deg]F) threshold for requiring 
temperature control to allow for additional time to conduct research on 
the impacts of such a change and to allow additional time to fully 
consider the issue. However, PHMSA-sponsored research, which was 
completed in February 2021 by APT Research, Inc. (APT),\16\ has 
informed our proposals in this NPRM. That research aimed to gather more 
information concerning temperature control of polymerizing substances 
in portable tanks and testing requirements for these substances 
intended to be transported in portable tanks or intermediate bulk 
containers (IBCs), as these two areas of safety controls in the HMR 
differed from those adopted in the international consensus standards 
and regulations. The report following research conducted by APT noted 
that ``relaxing the temperature control requirements as proposed by HM-
215N is assessed to be an appropriate approach since it will harmonize 
U.S. regulations with international requirements and no additional 
hazards were identified for any common polymers during transport. 
Polymers in industry with SAPTs approaching 45 [deg]C or 50 [deg]C were 
found to be uncommon.'' PHMSA agrees with this assessment and is 
proposing to lower this temperature threshold at which temperature 
control is required for portable tanks containing a material which is 
likely to decompose with a SADT or polymerize with a SAPT from 50 
[deg]C (122 [deg]F) or less to 45 [deg]C (113 [deg]F) or less. Although 
the APT research focused on polymerizing materials, PHMSA believes 
decomposing materials to behave similarly and has opted to apply the 
changed to both material types. PHMSA believes this proposed amendment 
will help facilitate international transportation of these goods and 
while maintaining the high standard of safety in the HMR for 
transportation of decomposing and polymerizing materials. To that end, 
PHMSA also proposes to amend the table in paragraph (f)(1) to 
accommodate

[[Page 34583]]

the specific temperature controls applicable to decomposing and 
polymerizing substances transported in portable tanks. This proposed 
amendment would align the HMR with temperature thresholds for 
substances with SADTs and SAPTs transported in portable tanks with 
those found in the UN Model Regulations and the IMDG Code. Further, 
based on this change specific to use of portable tanks, PHMSA would 
revise the table in paragraph (f)(1) to include packaging type as a 
factor in determining the criteria for control temperatures and 
emergency temperatures. Lastly, PHMSA proposes to amend paragraph (f) 
to provide a reference to the lower threshold of 45 [deg]C (113 [deg]F) 
for portable tanks and include a reference to proposed language 
concerning organic peroxides that require temperature control. 
Paragraph (f)(2) would be revised to (f)(2)(i)-(iii) to indicate 
general temperature control requirements for organic peroxides by type. 
These requirements are consistent with the UN Model Regulations and 
ensure that appropriate temperature control provisions are applied to 
organic peroxides not specifically listed in the Organic Peroxide Table 
in Sec.  173.225.
---------------------------------------------------------------------------

    \16\ Report can be accessed in Docket No. PHMSA-2021-0092 on 
www.regulations.gov.
---------------------------------------------------------------------------

    Additionally, to fully adopt these proposed changes, PHMSA proposes 
to remove the phaseout language currently found in (f)(1)(i), which 
states that the provisions concerning polymerizing substances in 
paragraph (f) will be effective until January 2, 2023. Finally, based 
on results of the research, PHMSA proposes to maintain the current 
defining criteria for polymerizing substances, in Sec.  173.124, that a 
polymerizing substance must successfully pass the UN Test Series E at 
the ``None'' or ``Low'' level, or achieve equivalent criteria using an 
alternative test method with the approval of the Associate 
Administrator, prior to selection of an appropriate portable tank or 
IBC. While this rulemaking action is being completed through the final 
rule stage, PHMSA directs stakeholders to review the enforcement 
discretion notice available on the PHMSA website \17\ and in this 
rulemaking docket for the continued movement of these materials in 
accordance with regulations in effect prior to January 2, 2023.
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    \17\ https://www.phmsa.dot.gov/regulatory-compliance/phmsa-guidance/phmsa-notice-enforcement-policy-regarding-international.
---------------------------------------------------------------------------

Section 173.27
    Section 173.27 outlines general requirements for transportation by 
aircraft, including requirements and limitations for hazardous 
materials transported in limited quantities. Currently, the provisions 
for combination packagings in paragraph (f)(2) specify that materials 
or articles not authorized as a limited quantity for transportation by 
aircraft include all PG I materials; self-reactive flammable solids in 
Division 4.1; spontaneously combustible materials in Division 4.2; and 
liquids that are dangerous when wet in Division 4.3. The ICAO Technical 
Instructions included similar language for Division 4.1 materials by 
allowing non-self-reactive Division 4.1 materials assigned to PG II or 
PG III to be transported as limited quantities. However, the ICAO DGP 
identified a conflict with limited quantity provisions in the ICAO 
Technical Instructions and the limited quantity provisions in the UN 
Model Regulations pertaining to four Division 4.1 materials, assigned 
PG II: ``UN 2555, Nitrocellulose with water with not less than 25 
percent water by mass''; ``UN 2556, Nitrocellulose with alcohol with 
not less than 25 percent alcohol by mass, and with not more than 12.6 
percent nitrogen, by dry mass''; ``UN 2557, Nitrocellulose, with not 
more than 12.6 percent nitrogen, by dry mass mixture with or without 
plasticizer, with or without pigment''; and ``UN 2907, Isosorbide 
dinitrate mixture with not less than 60 percent lactose, mannose, 
starch or calcium hydrogen phosphate.'' Despite not being defined as 
self-reactive, the UN Model Regulations have never included these 
specific Division 4.1 flammable solid materials for transport as 
limited quantities. The ICAO Technical Instructions were amended for 
consistency with the UN Model Regulations to clearly indicate that the 
transport of these four PG II materials in Division 4.1 are not 
authorized for transportation by aircraft as limited quantities. PHMSA 
proposes to add language in Sec.  173.27(f)(2)(i)(D) to explicitly 
include the UN identification numbers for these materials, indicating 
that these materials may not be transported as limited quantities by 
aircraft. PHMSA expects that this change will add an additional level 
of safety by correcting this packaging provision, which has been 
inconsistent with those in place for materials that pose similar 
hazards.
Section 173.124
    Section 173.124 outlines defining criteria for Divisions 4.1 
(Flammable solid), 4.2 (Spontaneously combustible), and 4.3 (Dangerous 
when wet material). In an earlier rulemaking, PHMSA placed phaseout 
dates on the HMR provisions concerning transport provisions for 
polymerizing substances to allow time for the completion of research on 
various topics concerning their transport and to gather and review 
empirical evidence concerning the appropriate transport provisions for 
polymerizing substances. In line with other amendments proposed in this 
NPRM for the transport of polymerizing substances, PHMSA is proposing 
to remove paragraph (a)(4)(iv), which is the phaseout date of January 
2, 2023. The result of this proposed amendment will be to remove the 
phaseout date and keep the existing requirements--as outlined in 
paragraph (a)(4)--effective beyond the January 2, 2023, date.
Section 173.137
    Section 173.137 prescribes the requirements for assigning a packing 
group to Class 8 (corrosive) materials. PHMSA proposes to authorize the 
use of an additional test method, Test No. 439, In Vitro Skin 
Irritation: Reconstructed Human Epidermis Test Method'' as well as 
editorial changes to this section to provide clarity regarding the use 
of the authorized OECD Guidelines for the Testing of Chemicals.
    Currently, the HMR requires offerors to classify Class 8 materials 
and assign a packing group based on tests performed in accordance with 
various OECD Guidelines for the Testing of Chemicals (TG), including a 
skin corrosion test (in vivo) and various in vitro testing guidelines 
that do not involve animal testing. Data obtained from the currently 
authorized test guidelines is the only data acceptable for 
classification and assignment of a packing group. Specifically for PG 
I, II, or III determinations, the HMR authorize the use of OECD 
Guidelines for the Testing of Chemicals, Test No. 435, ``In Vitro 
Membrane Barrier Test Method for Skin Corrosion'' and Test No. 404, 
``Acute Dermal Irritation/Corrosion'' (an in vivo test method). The HMR 
also authorize the use of OECD Test No. 430 ``In Vitro Skin Corrosion: 
Transcutaneous Electrical Resistance Test (TER)'' and Test No. 431, 
``In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test 
Method'', however the scope of what these tests can determine is 
limited. For that reason, Test No. 430 is authorized for use only to 
determine whether a material is corrosive or not; materials that are 
determined to be corrosive using this test require additional testing 
using Test Nos. 435 or 404 or assignment to the most conservative 
packing group, PG I. Similarly, Test No. 431 may also be used to 
determine whether or not a material is corrosive,

[[Page 34584]]

however while this can identify when a corrosive must be assigned PG I, 
it cannot differentiate between PG II and III materials. Consistent 
with the UN Model Regulations, when this method does not clearly 
distinguish between PG II or PG III, the HMR allow the material to be 
transported as PGII without further in vivo testing. Consistent with 
changes made to the 22nd revised edition of the UN Model Regulations, 
PHMSA proposes to authorize an additional TG, OECD Test No. 439, ``In 
Vitro Skin Irritation: Reconstructed Human Epidermis Test Method'', as 
an authorized test, which may be used to exclude a material from 
classification as a corrosive material. Test No. 439 was adopted in the 
UN Model Regulations because it provides another means of testing, 
without the use of live animals, that can easily identify materials as 
non-corrosive. However, while Test No. 439 may be used for the hazard 
identification of irritant chemicals, it is limited in that it simply 
allows materials to be identified as either corrosive or non-corrosive 
to skin. Because this test method only identifies the material as 
corrosive or not, the UN Model Regulations added an additional 
provision requiring that materials, which are tested using Test No. 439 
and indicate corrosivity, must be assigned to the most conservative PG 
(i.e., PG I), unless additional tests are performed to provide more 
specific data that can be used to assign a less conservative PG. The 
addition of Test No. 439 as an authorized test method will provide 
greater flexibility for shippers to classify, package, and transport 
corrosive material, while maintaining the HMR safety standard for 
transport of corrosive materials.
    With regard to the editorial changes in this section, PHMSA 
proposes to amend the text of this section to provide clarity regarding 
the authorized OECD Testing of Chemicals. Additionally, PHMSA proposes 
to amend the last paragraph of the introductory text, which currently 
states that assignment to packing groups I through III must be made 
based on data obtained from tests conducted in accordance with OECD 
Guideline Number 404 or Number 435, to remove the reference to Test No. 
435. Since its update in 2015, the criteria for packing group 
assignments in Test No. 435 are no longer the same as the criteria for 
Test Guideline 404. PHMSA expects that these amendments will enhance 
safety by providing clarity regarding the proper testing and assignment 
of packing groups and promote efficiency by streamlining the assignment 
of packing groups.
Section 173.167
    Section 173.167 contains the packaging instructions and exceptions 
for ID8000 consumer commodities. The ID8000 entry was added to the HMR 
in final rule HM-215K,\18\ with the intent of aligning the HMR with the 
ICAO Technical Instructions for the air transportation of limited 
quantities of consumer commodity material. Based on inquiries from 
shippers and carriers, PHMSA understands that confusion exists 
regarding the requirements for hazard communication and ability to 
withstand pressure differential for packages of ID8000, consumer 
commodity material when moved by modes other than air. In 2012 and 
2017, PHMSA issued letters of interpretation regarding the 
applicability and hazard communication requirements for ID8000 
shipments.\19\ Both of these letters of interpretation recognized that 
ID8000 shipments are inherently ``limited quantity'' and provided the 
opinion that for transportation by highway, rail, and vessel, ID8000 
packages could be marked with the standard marking found in Sec.  
172.315(a)(1) (i.e., without the ``Y''). In 2022, PHMSA received a 
petition for rulemaking, designated P-1762,\20\ from the Council on the 
Safe Transportation of Hazardous Articles (COSTHA) relating to ID8000.
---------------------------------------------------------------------------

    \18\ 76 FR 3307 (Jan. 19, 2011).
    \19\ Ref. No. 11-0090 (May 3. 2012); Ref. No. 16-0075 (Jan. 9, 
2016).
    \20\ https://www.regulations.gov/document/PHMSA-2022-0007-0001.
---------------------------------------------------------------------------

    In consideration of P-1762 and consistent with these letters of 
interpretation regarding the requirements for ID8000 shipments, PHMSA 
proposes to revise the requirements in Sec.  173.167 for ID8000, 
consumer commodity material. The intent of this proposed revision is to 
clearly address requirements for all modes of transportation, while 
continuing to recognize that the history and intent of the ID8000, 
consumer commodity, entry is closely tied to the ICAO Technical 
Instructions and air transportation.
    First, PHMSA proposes editorial revisions to the title of the 
section and introductory language in paragraph (a). PHMSA proposes to 
rename the section ``ID8000 consumer commodities'' to distinguish this 
section from the historical ``ORM-D, consumer commodity'' HMT entry and 
an exception that ceased to be effective on December 31, 2020. PHMSA 
purposely phased out the ``ORM-D, consumer commodity'' classification 
and description to remove the dual system of shipping certain limited 
quantities domestically and internationally, as it was a source of 
confusion.
    PHMSA acknowledges that there may be circumstances where persons 
need to transport ID8000 packages between locations--e.g., to a 
warehouse for consolidation, etc.--without needing or using air 
transportation. Therefore, PHMSA recognizes the need to not only 
accommodate that portion of transport but also provide assurances that 
any ID8000 package is appropriately prepared for air transportation, 
regardless of whether air transportation is actually used. PHMSA also 
proposes to clarify that ID8000 material is inherently a limited 
quantity, by adding the phrase ``limited quantity'' to the Sec.  
173.167(a) introductory text. Finally, PHMSA proposes to remove the 
phrase ``when offered for transportation by aircraft'' from the 
introductory language in paragraph (a) and to restructure the existing 
first sentence of the section into two separate statements. This 
revision is intended to clarify that the materials and quantities 
listed in this section may be transported by all modes and to clarify 
that only the materials listed in paragraph (a) are eligible to be 
transported as ``ID8000, consumer commodity.''
    More significantly, PHMSA proposes to revise the structure of the 
section by moving the two requirements in the currently effective 
language of paragraph (b)--applicable only to air transportation--to 
new subparagraphs (6) and (7) of paragraph (a). This would have the 
effect of making all packages of ID8000 material subject to the limited 
quantity marking requirements of Sec.  172.315(b) to include the ``Y'' 
limited quantity marking, and other markings required by part 172 
subpart D, including the ID number marking and PSN. This revision would 
also have the effect of requiring compliance with the Sec.  173.27(c) 
pressure differential requirement for transportation by all modes. The 
intent of this proposed revision is two-fold:
    1. Provide clarity to shippers on the hazard communication and 
pressure differential requirements for all shipments of ID8000, 
consumer commodity packages.
    2. Ensure that ID8000, consumer commodity packages--wherever they 
are in the transportation stream--meet the requirements for air 
transportation.
    As proposed, ID8000 packages would continue to be provided 
exceptions from shipping papers and labels when transported by highway 
and rail. PHMSA proposes to provide a labeling exception for ID8000 
packages transported by vessel, which aligns with the labeling 
exception provided to

[[Page 34585]]

limited quantity packages transported by vessel. PHMSA seeks comment on 
this proposed revision to the hazard communication and pressure 
differential packaging requirements for ID8000, consumer commodity 
packages.
    In addition to the revisions to Sec.  173.167 requested in P-1762 
discussed above, COSTHA submitted petition P-1761 \21\ and additional 
requests in P-1762 that PHMSA is not proposing to adopt into the HMR. 
Specifically, in P-1762, COSTHA requested that PHMSA add a reference to 
Sec.  173.167 in the individual sections that outline exceptions 
sections for Class 3, PG II and III (Sec.  173.150), UN3175 (Sec.  
173.151), Division 6.1 PG III (Sec.  173.153), UN3077, UN3082, UN3334 
and UN3335 (Sec.  173.155), and Class 2 non-toxic aerosols (Sec.  
173.306). PHMSA does not propose to adopt this portion of P-1762. 
ID8000 is a specialized exception, designed only for a small subset of 
materials, and the materials are subject to stringent packaging 
requirements. We believe that adding a reference to Sec.  173.167 to 
the exception sections listed above will create confusion for shippers 
by referencing an exception that most may not be able to adequately 
meet. All the materials and quantities authorized in Sec.  173.167 may 
be transported as limited quantities by all modes. For the vast 
majority of hazardous material shippers who offer these materials in 
these small quantities, utilizing the limited quantity exception is the 
most appropriate and simplest option. PHMSA requests comment on this 
determination not to adopt this portion of P-1762.
---------------------------------------------------------------------------

    \21\ https://www.regulations.gov/document/PHMSA-2022-0006-0001.
---------------------------------------------------------------------------

    Separately, in P-1761, COSTHA petitioned PHMSA to add a reference 
to the limited quantity marking section (Sec.  172.315) to the limited 
quantity packaging instructions in Sec. Sec.  173.150, 173.151, 
173.152, 173.153, 173.154, and 173.155. PHMSA does not propose to adopt 
the revision proposed in P-1761. Limited quantity shipments must be 
marked in accordance with Sec.  172.315 (see Sec.  172.315(a) and (b)). 
This longstanding requirement is clearly written in the HMR and PHMSA 
does not believe that any modification of the HMR is warranted. If 
shippers, carriers, or other entities involved in the transportation of 
hazardous materials are uncertain what marking requirements apply to a 
limited quantity shipment, that deficiency is best remedied through the 
proper implementation of a training program. PHMSA requests comment on 
this determination not to adopt P-1761.
Section 173.185
    Section 173.185 prescribes requirements for the transportation of 
lithium cells and batteries. PHMSA proposes numerous changes to this 
section as follows.
    Paragraph (a) classification revisions: Paragraph (a) provides 
general classification provisions, which include requirements for 
manufacturers and subsequent distributers of lithium cells and 
batteries to provide others in the supply chain a test summary of the 
battery, which contains information regarding the cells and batteries. 
PHMSA proposes to amend paragraph (a)(3) to except button cell 
batteries installed in equipment (including circuit boards) from these 
test summary requirements. This proposed amendment would give shippers 
of traditionally less regulated products, such as wrist watches and key 
fobs, an exception from the need to maintain a test summary. Currently, 
as provided in Sec.  173.185(c)(2) and (c)(3), button cell batteries 
are excepted from the lithium battery marking requirements and the 
packing requirement to use a strong, rigid outer package, provided the 
battery is sufficiently protected by the equipment in which it is 
contained. For this reason, PHMSA finds that this proposed amendment 
maintains the safety standard for the transportation of lithium 
batteries consistent with the Sec.  173.185(c) exceptions for smaller 
cells or batteries. Further, PHMSA proposes to make an editorial 
amendment by deleting the onset date of this requirement, January 1, 
2022, as this date has passed, and paragraph (a)(3) now applies 
generally.
    Additionally, PHMSA proposes to add a new paragraph (a)(5) to 
require marking the outer casing of lithium ion batteries with the 
Watt-hour (Wh) rating. This is consistent with the provisions for 
smaller cells or batteries in Sec.  173.185(c)(1)(i), which require 
that ``each lithium ion battery subject to this provision must be 
marked with the Watt-hour rating on the outside case.'' PHMSA added 
this provision to the HMR in HM-224F.\22\ While the requirement was 
added to the HMR for smaller cells or batteries (as a condition for use 
of an exception), no similar provision was added for other lithium ion 
cells and batteries (i.e., those not offered in accordance with, or 
eligible for, the paragraph (c) exceptions). However, upon review, 
PHMSA noted that the international regulations generally require the 
marking of the Wh rating on the outside of the casing. Specifically, 
this is required in accordance with Special Provision 348 of the UN 
Model Regulations, Special Provision 188 of the IMDG Code, Section IA.2 
of Packing Instruction 965 (for UN3480), and Section I.2 of Packing 
Instruction 966 (for UN3481) and 967 (for UN3481) of the ICAO Technical 
Instructions. PHMSA expects that this amendment will improve safety as 
the marking of the Wh rating on the outer casing of a lithium ion cell 
or battery assists a shipper in better understanding the energy 
capacity of the cell or battery, and thus, ensures compliance with 
hazard communication and packing provisions associated with Wh 
limitations.
---------------------------------------------------------------------------

    \22\ 79 FR 46011 (Aug. 6, 2014).
---------------------------------------------------------------------------

    Paragraph (b) packaging revisions: Section 173.185(b)(3) contains 
packaging provisions for lithium cells or batteries packed with 
equipment. Specifically, paragraph (b)(3)(iii) provides two authorized 
packaging configurations for lithium cells and batteries packed with 
equipment. Specifically, it permits lithium cells and batteries, when 
packed with equipment, to be placed in: (1) inner packagings that 
completely enclose the cell or battery, then placed in an outer 
packaging; or (2) inner packagings that completely enclose the cell or 
battery, then placed with equipment in a package that meets the PG II 
performance requirements as specified in paragraph Sec.  
173.185(b)(3)(ii). The intent of the first option provided in paragraph 
(b)(3)(iii)(A) is to permit packing only the cells or batteries in a UN 
specification packaging and then to place this packaging with the 
equipment, for which the batteries are intended, in a non-UN 
specification outer packaging. The intent for the second option 
provided in paragraph (b)(3)(iii)(B) is to pack both the cells/
batteries and the equipment in a UN specification outer packaging. In a 
working paper submitted at the ICAO 2020 Working Group Meeting, it was 
noted that the actual text for the two options was not clear. 
Specifically, paragraph (b)(3)(iii)(A) does not clearly state that the 
specification packaging containing the cells or batteries is then 
packed with the equipment into a non-specification outer packaging. 
Consistent with the clarifying revision in the ICAO Technical 
Instructions, and to align more closely with the text in packing 
instruction P903 of the UN Model Regulations, PHMSA proposes to revise 
paragraph (b)(3)(iii)(A) by clearly indicating that the cells or 
batteries must be placed in a specification package of a type that 
meets PG II performance requirements and then

[[Page 34586]]

placed together with the equipment in a strong, rigid outer non-
specification packaging. For additional clarity, PHMSA also proposes to 
revise paragraph (b)(3)(iii)(B) by replacing the text ``package'' with 
the phrase ``packaging of a type'' when referring to the specification 
package meeting the PG II performance requirements.
    PHMSA also proposes to add a new paragraph (b)(3)(iii)(C) to 
include a limitation for the number of batteries in the package, when 
transported by air. This is consistent with the provisions for smaller 
cells or batteries found in Sec.  173.185(c)(4)(vi), which currently 
requires that for smaller cells or batteries contained in or packed 
with equipment and shipped by aircraft, the number allowed in each 
package is limited to the number required to power the piece of 
equipment, plus two spare sets. The original provision limiting the 
number in each packaging was added in HM-224F but did not apply to 
fully regulated shipments.
    However, PHMSA notes that the limitation on the number of cells or 
batteries allowed in a package should apply to fully regulated 
shipments of lithium batteries packed with equipment, consistent with 
Section I.2 of Packing Instruction 966 (for UN3481) and Packing 
Instruction 969 (for UN3091) of the ICAO Technical Instructions. PHMSA 
did not intend to limit the scope of this requirement to just smaller 
cells or batteries, as a condition for the exception from full 
regulation under paragraph (c), as this packaging requirement is 
intended to limit the hazard of lithium battery shipments in air 
transportation. Limiting the number of batteries allowed to be packaged 
with equipment reduces hazard risks and increases safety.
    Section 173.185(b)(4) contains packaging provisions for lithium 
cells or batteries contained in equipment. Consistent with the ICAO 
Technical Instructions, PHMSA proposes to add a new paragraph 
(b)(4)(iv) clarifying that for transportation by aircraft, when 
multiple pieces of equipment are packed in the same outer packaging, 
each piece of equipment must be packed to prevent contact with other 
equipment. This change is necessary because existing provisions in 
paragraph (b) could be interpreted to only apply to an outer packaging 
containing a single piece of equipment; however, an outer packaging may 
contain multiple pieces of equipment. This provision would more clearly 
communicate that for multiple pieces of equipment containing lithium 
cells or batteries in the same outer packaging, the equipment must be 
packed to prevent damage due to contact between the pieces of 
equipment.
    Paragraph (c) exceptions for smaller cells or batteries revisions: 
Paragraph (c)(3) specifies hazard communication requirements pertaining 
to the use of the lithium battery mark. Currently, the heading of 
paragraph (c)(3) is titled ``hazard communication''; however, PHMSA 
proposes to amend this heading to read ``lithium battery mark.'' In 
general, hazard communication refers to various documentation and 
communication requirements, including but not limited to marking. PHMSA 
expects that this change will provide clarity by referring to the 
specific requirement for hazard communication stipulated in this 
paragraph. PHMSA proposes to remove the telephone number requirement 
from the lithium battery mark. The intended use of the telephone number 
and its effectiveness was discussed by the UNSCOE. Examples pointing to 
its ineffectiveness include differences in time zones and languages 
between the origin and destination of a shipment or intermediate 
transport point, and a lack of clarity on the expected capability of 
the person responding to a telephone call. The requirement to include a 
``telephone number for additional information'' was originally 
introduced in the 15th revised edition of the UN Model Regulations. It 
was envisioned that the telephone number would be for the consignor or 
other responsible individual who could provide further information 
(e.g., appropriate corrective actions should something be wrong with 
the package) beyond the minimal information required to be indicated on 
the package. At that time, there was minimal hazard communication and 
less awareness than is currently provided for in the UN Model 
Regulations. The consignor information can now be readily obtained 
through other means such as a bill of lading, shipping labels, or other 
paperwork thereby rendering the telephone number requirement as a piece 
of information on the lithium battery mark effectively redundant. The 
resulting consensus based on both the discussion and experience with 
transport of small lithium batteries was that the telephone number adds 
little value and removing the telephone number requirement from the 
mark would not reduce the effectiveness of the mark and therefore, not 
impact safety of transportation. Specifically, PHMSA proposes to revise 
the lithium battery mark by removing the double asterisk from the 
example figure and the corresponding requirement in paragraph 
(c)(3)(i)(C) to replace the double asterisk with the telephone number. 
PHMSA proposes a transition period authorizing continued use of the 
current lithium battery mark until December 31, 2026.
    Section 173.185(c) provides exceptions for smaller cells or 
batteries. Paragraph (c)(4) contains provisions for exceptions for 
smaller lithium cells and batteries offered by air transportation. 
PHMSA proposes to remove the exceptions applicable to small lithium 
cells and batteries when they are not packed with, or contained in, 
equipment. This change was also implemented on January 1, 2022, by the 
International Air Transport Association (IATA) and member airlines will 
no longer accept packages of lithium batteries prepared in accordance 
with Section II of Packing Instructions 965 and 968 of the ICAO 
Technical Instructions. These exceptions in Sec.  173.185(c)(4), had 
been developed to facilitate the global transport of small lithium 
cells and batteries. However, these exceptions removed many of the 
regulatory safeguards that provide for the safe transport of lithium 
batteries, including requirements for air operators to perform an 
acceptance check, information to be provided to the pilot-in-command, 
and package hazard communication. Furthermore, the exceptions for small 
lithium cells and batteries limit the ability of air operators to 
conduct the necessary safety risk assessments. The reduced hazard 
communication also increases the risk of small lithium cells and 
battery packages restricted to transport on cargo aircraft only being 
inadvertently loaded on a passenger aircraft. This proposed removal of 
these exceptions would increase the visibility of these shipments to 
operators who could perform an acceptance check to ensure proper 
packaging and hazard communication and ensure the information regarding 
the number and location of packages containing lithium batteries will 
be provided to the pilot-in-command. The proposed changes do not apply 
to the exceptions for small lithium cells and batteries packed with, or 
contained in, equipment. Specifically, PHMSA proposes to remove the 
following provisions:
     Paragraph (c)(4)(i), including Table 1 regarding the 
number and net quantity of lithium batteries.
     In paragraph (c)(4)(ii), the first sentence with reference 
to (c)(4).
     Paragraph (c)(4)(iii), regarding limitation of one package 
per consignment.
     Paragraph (c)(4)(v), regarding offering packages and 
overpacks to an

[[Page 34587]]

operator separately from cargo not subject to the HMR.
     Paragraph (c)(4)(viii), regarding packing cells and 
batteries with other hazardous materials in the same package or 
overpack.
    As a consequence, the remaining provisions in paragraph (c)(4) 
applicable to lithium cells or batteries packed with, or contained in, 
equipment would be reorganized and renumbered. The paragraph (c)(4) 
introductory text would be revised to read ``Air Transportation. 
Smaller Lithium cell or batteries packed with, or contained in, 
equipment.'' Further, consistent with the ICAO Technical Instructions, 
paragraph (c)(4)(ii), concerning overpacks, would be revised to add a 
packing instruction that when placed into an overpack, packages must be 
secured within the overpack, and the intended function of each package 
must not be impaired by the overpack. The general provisions for 
overpacks in Part 5; 1.1 of the ICAO Technical Instructions require 
that packages must be secured within the overpack, and that the 
intended function of the package must not be impaired by the overpack. 
However, with the current construction of the provisions for small 
batteries in Packing Instructions 966, 967, 969, and 970, the general 
Part 5 overpack provisions do not apply, which could lead to packages 
being unsecured or even damaged by being unrestrained within an 
overpack. Therefore, these overpack provisions from Part 5 were added 
to the respective packing instructions to ensure protection against 
damage of the packages and their contents. These changes are consistent 
with the elimination of ``Section II'' from Packing Instructions 965 
and 968 in the ICAO Technical Instructions. These proposed amendments 
maintain the level of safety (i.e., hazard communication clarifications 
and revisions to lithium battery requirements for consistency). All the 
proposed amendments are expected to maintain the HMR's high safety 
standard. Safety benefits will also be derived from improved compliance 
related to consistency amongst domestic and international regulations. 
PHMSA solicits comment on the amendments proposed in this NPRM 
pertaining to need, benefits and costs; impact on safety and the 
environment; impact on environmental justice and equity; and any other 
relevant information.
    Section 173.185(c)(5), corresponding to Section IB in ICAO 
Technical Instructions Packing Instructions 965 and 968, provides an 
exception from specification packing requirements for smaller lithium 
cells and batteries, not exceeding the size prescribed in paragraph 
(c)(1) and subject to certain quantity limits. PHMSA proposes to revise 
the paragraph (c)(5) introductory text to ``Air Transportation. Smaller 
lithium cell and batteries.'' Combined with the revision of the (c)(4) 
introductory text, this will assist users of this section by 
identifying the subparagraphs in paragraph (c) containing additional 
air transport provisions for lithium batteries, packed with, or 
contained in, equipment, and those only applicable to lithium cells and 
batteries. PHMSA proposes to revise paragraph (c)(5) by requiring 
packages to be capable of withstanding a three-meter stack test for a 
duration of 24 hours. Because lithium cells and batteries offered in 
accordance with paragraph (c)(5) (which corresponds with IB of Packing 
Instructions 965 and 968 of the ICAO Technical Instructions) are 
excepted from the specification package requirements, they are not 
presently subject to a stack test. However, the general requirements 
for limited quantity packages by air in Sec.  173.27(f)(2)(vi), which 
are also excepted from specification packaging requirements, do require 
that each package be capable of withstanding a three-meter stack test 
for a duration of 24 hours. In considering the packaging standards 
between limited quantity packages and those for smaller lithium cells 
and batteries, it was agreed by the DGP that packages must be capable 
of withstanding a stack test, in parallel with the requirement for 
limited quantity packages. PHMSA agrees with introducing a stack test 
as a preventative safety measure against potential damage to lithium 
battery packages from stacking of packages and proposes to include a 
stack test requirement in paragraph (c)(5).
    Lastly, consistent with corresponding revisions to international 
standards, PHMSA is proposing editorial revisions in paragraphs (b)(5), 
(e)(5), (e)(6), and (e)(7), where references to ``battery assemblies'' 
are removed and replaced with the phrase ``cells and batteries,'' as 
used throughout the section. Paragraph 173.185(a)(1) requires each 
lithium cell or battery to be of the type proven to meet the criteria 
in part III, sub-section 38.3 of the UN Manual of Tests and Criteria. 
The 38.3.2.3 definition for ``battery'' states that:

    ``. . . Units that are commonly referred to as ``battery 
packs,'' ``modules'' or ``battery assemblies'' having the primary 
function of providing a source of power to another piece of 
equipment are, for the purposes of the Model Regulations and this 
Manual, treated as batteries.''

    Use of ``battery assemblies'' may be a source of confusion, as the 
reader may understand it to have a separate meaning from ``battery,'' 
yet it is not specifically defined in the HMR. Further, based on the 
requirement above to comply with the UN Manual of Tests and Criteria 
and its associated meaning of ``battery assemblies,'' PHMSA considers 
that the use of the term ``battery assemblies'' is redundant with the 
term ``battery'' in the context of these transport requirements and 
proposes to revise the text to reduce confusion of the provisions in 
these paragraphs, regarding applicability to the assembly or to the 
cells and batteries contained within an assembly. PHMSA expects that 
the proposed changes to Sec.  173.185 will provide clarity, thus 
enhancing the safety standard in the HMR for transportation of lithium 
batteries.
Section 173.224
    Section 173.224 establishes packaging and control and emergency 
temperatures for self-reactive materials. The Self-Reactive Materials 
Table in paragraph (b) of this section specifies self-reactive 
materials authorized for transportation without first being approved 
for transportation by the Associate Administrator for Hazardous 
Materials Safety and requirements for transporting these materials. As 
a result of new self-reactive materials formulations becoming 
commercially available, the 22nd revised edition of the UN Model 
Regulations includes updates to the list of specified self-reactive 
materials authorized for transportation without prior approval. To 
maintain consistency with the UN Model Regulations, PHMSA proposes to 
update the Self-Reactive Materials Table by adding a new entry for 
``(7-Methoxy-5-methyl-benzothiophen-2-yl) boronic acid''. PHMSA also 
proposes to correct the name of one of the listed self-reactive 
substances on the self-reactive substances table. Currently, ``2-(N,N-
Methylaminoethylcarbonyl)-4-(3,4-dimethyl-phenylsulphonyl)benzene 
diazonium zinc chloride'' is listed, however this formulation name 
should be ``2-(N,N-Methylaminoethylcarbonyl)-4-(3,4-
dimethylphenylsulphonyl)benzenediazonium hydrogen sulphate''. While 
reviewing the self-reactive table in the UN Model Regulations and ICAO 
Technical Instructions, PHMSA discovered that ``2-(N,N-
Methylaminoethylcarbonyl)-4-(3,4-dimethyl-phenylsulphonyl)benzene 
diazonium zinc chloride'' does not appear in any other international 
regulations but that ``2-(N,N-

[[Page 34588]]

Methylaminoethylcarbonyl)-4-(3,4-
dimethylphenylsulphonyl)benzenediazonium hydrogen sulphate'' does and 
includes identical packaging provisions. PHMSA does not believe that 
there is any formulation called ``2-(N,N-Methylaminoethylcarbonyl)-4-
(3,4-dimethyl-phenylsulphonyl)benzene diazonium zinc chloride'' that 
exists and that this entry as it appears is the result of an editorial 
error in which two individual formulation names were inadvertently 
combined. Therefore, PHMSA proposes to correct the name associated with 
this formulation by removing the suffix ``benzene diazonium zinc 
chloride'' and replacing it with ``benzenediazonium hydrogen 
sulphate.'' PHMSA requests comment regarding this change, specifically 
regarding whether the deletion of ``2-(N,N-Methylaminoethylcarbonyl)-4-
(3,4-dimethyl-phenylsulphonyl)benzene diazonium zinc chloride'' should 
be reconsidered.
    In addition, PHMSA proposes assigning a new ``Note 6'' to this 
entry among the list of notes following the table. ``Note 6'' would 
provide concentration limits of water and organic impurities for this 
new self-reactive material. PHMSA expects that adding provisions for 
the transport of (7-Methoxy-5-methyl-benzothiophen-2-yl) boronic acid 
formulations will facilitate its transport while maintaining the HMR's 
safe standard for transportation of self-reactive hazardous materials.
    PHMSA also proposes to revise Sec.  173.224(b)(4). In a previous 
final rule, HM-215O, PHMSA revised Sec.  173.224 to authorize self-
reactive materials to be transported and packed in accordance with 
packing method OP8 where transport in IBCs or portable tanks is 
permitted in accordance with Sec.  173.225, provided that the control 
and emergency temperatures specified in the instructions are complied 
with. This change allowed materials that are authorized in bulk 
packagings to also be transported in appropriate non-bulk packagings. 
PHMSA proposes to make an editorial correction to a reference to the 
formulations listed in Sec.  173.225. In the course of adding this 
provision, PHMSA incorrectly directed users to the Organic Peroxide IBC 
Table by referencing 173.225(f) however the table is found in 
173.225(e); therefore, PHSMA proposes to correct that sentence to refer 
to 173.225(e).
Section 173.225
    Section 173.225 prescribes packaging requirements and other 
provisions for organic peroxides. As a result of new peroxide 
formulations becoming commercially available, the 22nd revised edition 
of the UN Model Regulations includes updates to the list of identified 
organic peroxides, which provides for formulations of these materials 
that are authorized for transportation without prior approval. To 
maintain consistency with the UN Model Regulations, PHMSA proposes to 
update the Organic Peroxide Table in Sec.  173.225(c) by adding new 
entries for ``tert-Butylperoxy isopropylcarbonate,'' ``tert-hexyl 
peroxypivalate,'' and ``acetyl acetone peroxide,'' and identifying them 
as ``UN3105, Organic peroxide type D, liquid''; ``UN3117, Organic 
peroxide type E, liquid, temperature controlled''; and ``UN3107, 
Organic peroxide type E, liquid,'' respectively. Additionally, PHMSA 
proposes to add a ``Note 32'' following the table, in association with 
the new entry for ``acetyl acetone peroxide,'' to indicate that the 
active oxygen concentration for this formulation is limited to 
concentrations of 4.15% active oxygen or less. PHMSA also proposes to 
revise the Organic Peroxide Portable Tank Table in paragraph (g) to 
maintain alignment with the 22nd revised edition of UN Model 
Regulations by adding new formulation ``tert-Butyl hydroperoxide, not 
more than 56% with diluent type B,'' identified by ``UN3109, Organic 
peroxide type F, liquid.'' This amendment would also include the 
addition of ``Note 2'' following the table to specify that diluent type 
B is tert-Butyl alcohol. PHMSA expects that adding provisions for the 
transport of these newly available peroxide formulations will 
facilitate transportation of these materials, while maintaining the 
HMR's safety standard for transportation of organic peroxide hazardous 
materials.
Section 173.232
    Section 173.232 outlines the packaging requirements for articles 
containing hazardous materials. For the purposes of this section, an 
``article'' means machinery, apparatus, or other device that contains 
one or more hazardous materials--or residues thereof--that are an 
integral element of the article, necessary for its functioning, and 
that cannot be removed for the purpose of transport. Currently, these 
articles are forbidden from transport on passenger and cargo aircraft, 
as specified in column (9) of the HMT. However, the 2023-2024 ICAO 
Technical Instructions include new provisions permitting the transport 
of certain articles containing hazardous materials aboard passenger and 
cargo aircraft. These new provisions allow articles described and 
classified as ``UN3548, Articles containing miscellaneous dangerous 
goods, n.o.s., 9'' or ``UN 3538, Articles containing non-flammable, 
non-toxic gas, n.o.s., 2.2'' to be transported by cargo and passenger 
aircraft under certain conditions. PHMSA proposes to make changes 
consistent with those provisions by adding two new packaging provisions 
in Sec.  173.232, in addition to the new special provisions A224 and 
A225 discussed above in Section-by-Section Review of NPRM Proposals for 
Sec.  172.102. Specifically, PHMSA proposes to specify in paragraph (h) 
that air transport is permitted for UN3548 articles containing less 
than 5 L or 5 kg of environmentally hazardous substances when all other 
conditions of Sec.  173.232 are met. In a new paragraph (i), the same 
requirements are proposed for articles transported under UN3538, which: 
(1) do not have an existing proper shipping name; (2) contain only 
gases of Division 2.2 without a subsidiary hazard, except for 
refrigerated liquefied gases and other gases that are forbidden for 
transport on passenger aircraft, where the quantity of the Division 2.2 
gas exceeds the quantity limits for UN 3363, as prescribed in Sec.  
173.222; (3) the quantity of gas in the article does not exceed 75 kg 
when transported by passenger aircraft or 150 kg when transported by 
cargo aircraft; and (4) gas containing receptacles within the article 
must meet the requirements of Part 173 and Part 175, as appropriate., 
or meet a national or regionally recognized pressure receptacle 
standard.
    Additionally, both packaging provisions would also permit the 
transport of these articles, containing lithium cells or batteries, 
provided that the batteries meet the requirements specified in Sec.  
173.185. The aim of these new provisions is to facilitate the transport 
of large articles containing environmentally hazardous substances, such 
as aircraft landing gear struts filled with hydraulic fluid and large 
articles containing a non-flammable, non-toxic gas, such as new types 
of magnetic resonance imaging (MRI) scanners, which often contain 
compressed helium, as well as lithium cells or batteries. As a 
participant on the Dangerous Goods Panel, PHMSA expects that the 
proposed packaging provisions provide an appropriate level of safety to 
allow these items to be transported by air and are appropriate for 
incorporation in the HMR.
Section 173.301b
    Section 173.301b outlines additional general requirements when 
shipping gases in UN pressure receptacles (e.g., cylinders). The 22nd 
revised edition of

[[Page 34589]]

the UN Model Regulations updated references of several authorized 
standards for ensuring proper valve protection. In order to maintain 
the current safety standard of the HMR for valve protection and 
harmonization with the requirements for UN pressure receptacles, PHMSA 
proposes to also update these references. Currently, paragraph (c)(1) 
requires that quick release cylinder valves for specification and type 
testing must conform to the requirements in ISO 17871:2015(E), ``Gas 
cylinders--Quick-release cylinder valves--Specification and type 
testing.'' ISO 17871, in conjunction with ISO 10297 and ISO 14246, 
specifies design, type testing, marking, manufacturing tests, and 
examination requirements for quick-release cylinder valves, intended to 
be fitted to refillable transportable gas cylinders and pressure drums 
and tubes used to transport compressed or liquefied gases or 
extinguishing agents charged with compressed gases to be used for fire-
extinguishing, explosion protection, and rescue applications. As part 
of its regular review of its standards, ISO updated and published the 
second edition of ISO 17871 as ISO 17871:2020(E). PHMSA proposes to 
revise the valve requirements in this paragraph to require quick 
release cylinder valves for specification and type testing to conform 
to ISO 17871:2020(E). After December 31, 2026, conformance with ISO 
17871:2015(E) will no longer be authorized in the UN Model Regulations; 
therefore, for consistency, PHMSA also proposes to add a phaseout date 
of December 31, 2026, for continued conformance with ISO 17871:2015(E). 
The second edition of this standard broadens the scope to include quick 
release valves for pressure drums and tubes and specifically excludes 
the use of quick-release valves with flammable gases. Other notable 
changes include the addition of the valve burst test pressure, the 
deletion of the flame impingement test, and the deletion of the 
internal leak tightness test at -40 [deg]C for quick-release cylinder 
valves, used only for fixed firefighting systems installed in 
buildings. PHMSA expects that updating the requirements for conformance 
of UN pressure receptacles with this document will maintain the HMR 
safety standard for these packagings and facilitate compliance with 
valve requirements domestically and internationally by aligning the HMR 
with changes adopted in the 22nd revised edition of the UN Model 
Regulations. PHMSA reviewed this edition as part of its regular 
participation in the review of amendments proposed for the UN Model 
Regulations.
    PHMSA also proposes to revise paragraph (c)(2), which requires UN 
pressure receptacles to have their valves protected from damage to 
prevent unintentional release of the contents of the receptacles. 
Various methods on how to achieve damage protection are provided, 
including equipping the container with a valve cap or guard that 
conforms to ISO 11117:2008, ``Gas cylinders--Valve protection caps and 
guards--Design, construction and tests'' and the Technical Corrigendum 
1, a complementary document to the standard. As part of its regular 
review of its existing standards, in 2019, ISO published an updated 
version of this standard, 11117:2019, which was adopted in the 22nd 
revised edition of the UN Model Regulations as a permitted conformance 
standard for valve protection. This document updates the 2008 version, 
currently authorized in paragraphs (c)(2)(ii) and (c)(2)(iii). In 
accordance with the UN Model Regulations, PHMSA also proposes to 
authorize the continued use of ISO 11117:2008, in conjunction with the 
Technical Corrigendum, until December 31, 2026. Similarly, for metal 
hydride storage systems, damage protection of the valve must be 
provided in accordance with ISO 16111:2008, ``Transportable gas storage 
devices--Hydrogen absorbed in reversible metal hydride.'' As part of 
its regular review of its existing standards, in 2018, ISO published an 
updated version of this standard, which was adopted in the 22nd revised 
edition of the UN Model Regulations as a permitted conformance standard 
for valve protection. Therefore, to maintain alignment with the UN 
Model Regulations' requirements for UN metal hydride storage systems, 
PHMSA proposes to update the required standard for protection of valves 
to ISO 16111:2018 and include a phaseout date of December 31, 2026, for 
continued use of valve guards conforming to valve protection standards 
in ISO 16111:2008. PHMSA has reviewed the updated ISO standards as part 
of its regular participation in the review of amendments proposed for 
the UN Model Regulations and has determined use of the update ISO 16111 
will maintain the HMR safety standard for protection of valves used in 
UN metal hydride storage systems.
    Paragraph (d) requires that when the use of a valve is prescribed, 
the valve must conform to the requirements in ISO 11118:2015(E), ``Gas 
cylinders--Non-refillable metallic gas cylinders--Specification and 
test methods.'' ISO 11118:2015 specifies minimum requirements for the 
material, design, inspections, construction and workmanship, 
manufacturing processes, and tests at manufacture of non-refillable 
metallic gas cylinders of welded, brazed, or seamless construction for 
compressed and liquefied gases including the requirements for their 
non-refillable sealing devices and their methods of testing. For 
consistency with the UN Model Regulations, PHMSA proposes to revise the 
valve conformance requirements to include a reference to the 2019 
amendment of ISO 11118, specifically, ISO 11118:2015/Amd 1:2019, which 
ISO published as a supplement to ISO 11118:2015(E). This supplement 
corrects the references and numerous typographical errors. The 
amendment also includes updates to the marking requirements in the 
normative Annex A, which includes clarifications, corrections, and new 
testing requirements. Additionally, paragraph (d) currently indicates 
that the manufacture of valves to ISO 13340:2001(E) is authorized until 
December 31, 2020. Since this date has passed, PHMSA proposes to remove 
reference to this expired authorization.
    Updating references to these documents would align the HMR with 
changes adopted in the 22nd revised edition of the UN Model Regulations 
pertaining to the design and construction of UN pressure drums. PHMSA 
has reviewed this edition as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and does not 
expect any degradation of safety standards in association with its use.
    Lastly, paragraph (f) of this section requires that for the 
transportation of hydrogen bearing gases, a steel UN pressure 
receptacle bearing an ``H'' mark must be used. The ``H'' marking 
indicates that the receptacle is compatible with hydrogen embrittling 
gases. However, some hydrogen bearing gases may also be transported in 
composite pressure receptacles with steel liners as provided in Sec.  
173.311. Therefore, PHMSA proposes to amend Sec.  173.301b(f) to 
clarify that these compatibility provisions apply to steel UN cylinders 
as well as composite pressure receptacles that include steel liners. 
PHMSA expects that this amendment will add an additional level of 
safety by ensuring that suitability of materials is considered when 
shippers opt to use composite cylinders for the transport of hydrogen 
bearing gases.
Section 173.302c
    Section 173.302c outlines additional requirements for the shipment 
of

[[Page 34590]]

adsorbed gases in UN pressure receptacles. Currently paragraph (k) 
requires that filling of UN pressure receptacles with adsorbed gases be 
performed in accordance with Annex A of ISO 11513:2011, ``Gas 
cylinders--Refillable welded steel cylinders containing materials for 
sub-atmospheric gas packaging (excluding acetylene)--Design, 
construction, testing, use and periodic inspection.'' As part of its 
periodic review and updates of standards, ISO has developed an updated 
second edition (published in 2019). The updated ISO 11513 standard was 
adopted in the 22nd revised edition of the UN Model Regulations for use 
for cylinders filled with adsorbed gases. Similarly, PHMSA proposes to 
require use of Annex A of ISO 11513:2019. Specifically, this amendment 
would require the use of the 2019 standard and provide a phaseout date 
for continued use of the ISO 11513:2011 until December 31, 2024. 
Updating references to this document would align the HMR with changes 
adopted in the 22nd revised edition of the UN Model Regulations 
pertaining to the shipment of adsorbed gases in UN pressure 
receptacles. PHMSA has reviewed this edition as part of its regular 
participation in the review of amendments proposed for the UN Model 
Regulations and does not expect any degradation of safety standards in 
association with its use.
Section 173.311
    Section 173.311 specifies requirements for transportable UN metal 
hydride storage systems (UN3468) that are comprised of pressure 
receptacles not exceeding 150 L (40 gallons) in water capacity and 
having a maximum developed pressure not exceeding 25 MPa (145 psi). 
Currently, the HMR requires that these metal hydride storage systems be 
designed, constructed, initially inspected, and tested in accordance 
with ISO 16111:2008, ``Transportable gas storage devices--Hydrogen 
absorbed in reversible metal hydride.'' However, the 22nd revised 
edition of the UN Model Regulations updated references to this standard 
to authorize the use of the updated 2018 version of ISO 16111, while 
allowing the 2008 version to remain authorized for use until December 
31, 2026. Therefore, for consistency with the requirements for UN metal 
hydride storage systems, PHMSA proposes to adopt changes made in the 
22nd revised edition of the UN Model Regulations to authorize the use 
of ISO 16111:2018 and add a phaseout date of December 31, 2026, for 
continued use of ISO 16111:2008. PHMSA has reviewed this edition as 
part of its regular participation in the review of amendments proposed 
for the UN Model Regulations and has determined the updated edition of 
ISO 16111 will maintain the HMR safety standards for the design, 
construction, initial inspection, and testing of UN metal hydride 
storage systems.

D. Part 175

Section 175.1
    Section 175.1 outlines the purpose, scope, and applicability of the 
Part 175 requirements for the transport of hazardous materials by 
aircraft. Specifically, these requirements are in addition to other 
requirements contained in the HMR. The aircraft-level risk presented by 
hazardous materials depends on factors, such as the total quantity and 
type, potential interactions, and existing risk mitigation measures. 
When accepting hazardous materials for transportation by aircraft, 
aircraft operators (i.e., air carriers) must also comply with Federal 
Aviation Administration (FAA) Safety Management System (SMS) 
requirements in 14 CFR part 5--Safety Management Systems, that impacts 
how operators comply with requirements of the HMR.
    PHMSA proposes to add a new paragraph (e) to the HMR that includes 
a reference that directs operators to the FAA's requirements to have an 
SMS in place, in accordance with 14 CFR part 121. Safety risk 
management is the process within the SMS composed of describing the 
system, identifying the hazards, and analyzing, assessing, and 
controlling risk. According to 14 CFR part 5, certain aircraft 
operators are certificated, in accordance with 14 CFR part 121, to the 
appropriate SMS requirements and a note referencing guidance for 
performing a safety risk assessment. This action will not introduce new 
regulatory burden, as these SMS requirements have been in place for 
several years. However, PHMSA expects that adding a reference to these 
requirements in the HMR will provide additional clarity for aircraft 
operators, with respect to the applicability of SMS to the acceptance 
and transport of hazardous materials at the aircraft level. Finally, 
PHMSA notes that FAA Advisory Circular (AC) 120-121 \23\ provides 
information relating to the risk assessments and potential mitigation 
strategies to items in the aircraft cargo compartment. When using this 
document, aircraft operators should refer to requisite ICAO documents, 
check the FAA websites for additional information on cargo safety and 
mitigations relating to fire events, and consider safety enhancements 
developed and promoted by industry groups.
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    \23\ https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_120-121.pdf.
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Section 175.10
    Section 175.10 specifies the conditions under which passengers, 
crew members, or an operator may carry hazardous materials aboard an 
aircraft. Consistent with revisions to the ICAO Technical Instructions, 
PHMSA proposes revisions in paragraphs (a)(15) and (a)(17) applicable 
to the carriage of wheelchairs or other mobility aids powered by 
batteries. Specifically, in paragraphs (a)(15)(v), (a)(15)(vi) and 
(a)(17)(v), which currently require that the battery be securely 
attached to the wheelchair or mobility aid or be removed and packed 
appropriately, PHMSA proposes to add the supplemental requirements that 
the battery is adequately protected against damage by the design of the 
wheelchair or mobility aid. The proposed revisions will enhance the 
safe carriage of these battery-powered items aboard passenger aircraft 
by requiring combined measures of protection against damage and 
securement of batteries or otherwise removed and packed appropriately. 
Furthermore, the proposed revisions will assist passengers traveling 
with battery-powered wheelchairs or mobility aids by providing better 
clarity on the required safety measures. Additionally, PHMSA proposes 
to revise introductory text to paragraphs (a)(14) and (a)(26) to 
specifically state that each lithium battery must be of a type which 
meets the requirements of UN Manual of Tests and Criteria, Part III, 
Subsection 38.3. Currently this requirement is outlined in every other 
subparagraph under paragraph (a) pertaining to lithium batteries but 
was inadvertently omitted in prior rulemakings for paragraphs (a)(14) 
and (a)(26). Therefore, for clarity and consistency with the ICAO 
Technical Instructions, PHMSA proposes this editorial change, and 
expects that it will improve safety by ensuring that it is understood 
that all batteries transported under the provisions of that paragraph 
are subject to UN testing.
    PHMSA also proposes to revise paragraph (a)(18) regarding the 
carriage of portable electronic devices (e.g., watches, cell phones, 
etc.). Currently, the HMR allows these devices to be carried both in 
carry-on baggage and checked baggage. However, this paragraph 
stipulates that for lithium battery-powered devices carried in

[[Page 34591]]

checked baggage, the devices must be completely switched off (i.e., not 
in sleep or hibernation mode). The requirement to turn off battery 
powered devices was added in the ICAO Technical Instructions and the 
HMR as a result of temporary security restrictions that prohibited the 
carriage of large portable electronic devices in the cabin on certain 
flights. In addition to the restriction of electronic devices in the 
aircraft cabin, a requirement to turn off all devices powered by 
lithium batteries when placed in checked baggage was added to prevent 
risks from overheating in those devices that might remain active when 
not powered off (e.g., laptops). This requirement to turn devices off 
was applied to all devices powered by batteries or cells, regardless of 
their size and level of risk, primarily to simplify the regulations and 
facilitate its implementation. However, in light of the need for 
passengers to carry active devices powered by small cells in checked 
baggage (e.g., small tracking devices), PHMSA proposes to provide some 
conditional relief from this requirement for passengers and crew by 
applying the provision to switch off the device to only those devices 
powered by lithium metal batteries exceeding 0.3 grams lithium content 
or lithium ion batteries exceeding 2.7 Wh. This is consistent with 
paragraph (a)(26) which allows baggage equipped with lithium batteries 
to be carried as checked baggage if the batteries do not exceed 0.3 
grams of lithium content or 2.7 Wh, respectively. Based on similar 
battery size criteria in paragraph (a)(26), PHMSA does not expect a 
reduction in safety of transporting lithium battery-powered devices 
aboard passenger aircraft under the proposed exception. Moreover, small 
lithium battery-powered devices are not known or expected to create 
heat in the same manner as portable electronic devices powered by much 
larger batteries. PHMSA expects that this amendment will avoid 
unnecessary operational challenges for States, operators, and the 
travelling public without compromising safety.
    Additionally, PHMSA proposes to add clarification in paragraph (a) 
that the most appropriate exception from this section shall be selected 
when hazardous materials are carried by aircraft passengers or 
crewmembers. For example, paragraph (a)(19) specifies conditions for 
battery-powered smoking devices such that a person cannot opt to follow 
the more generalized portable electronic device conditions of paragraph 
(a)(18). PHMSA expects that this clarification will support the safe 
transport of excepted hazardous materials by ensuring that they will be 
transported in a manner that is most appropriate for the hazard they 
may pose.
    Finally, PHMSA proposes to make a clarifying amendment to paragraph 
(a)(26) regarding baggage equipped with lithium batteries. Oftentimes, 
the baggage has built-in features that cannot be turned off and the 
intent of paragraph (a)(26) is the devices are not required to be 
turned off when the baggage is checked. Therefore, PHMSA proposes to 
clarify paragraph (a)(26) to state plainly that, under the conditions 
allowing baggage to be checked without removing the batteries, 
electronic features of the baggage do not have to be switched off.
Section 175.33
    Section 175.33 establishes requirements for shipping papers and for 
the notification of the pilot-in-command when hazardous materials are 
transported by aircraft. Consistent with the proposed removal of the 
exceptions applicable to small lithium cells and batteries, as 
discussed in the Section-by-Section Review discussion of changes in 
Sec.  173.185(c), PHMSA proposes to revise paragraph (a)(13)(iii) to 
remove reference to UN3480, lithium ion batteries and UN3090 lithium 
metal batteries. Currently, paragraph (a)(13)(iii) conditionally 
excepts certain lithium batteries \24\ that are prepared in accordance 
with the paragraph Sec.  173.185(c) exceptions for smaller cells and 
batteries from the requirement to be included with the information to 
be provided to the pilot-in-command. Since smaller lithium cells and 
batteries that are not packed with or contained in equipment are no 
longer provided relief from hazard communication requirements, such as 
shipping papers, PHMSA proposes a conforming change to this section to 
also require the inclusion of lithium cells and batteries as part of 
the information provided to the pilot-in-command. This revision will 
maintain the HMR standard of hazard communication for transportation of 
lithium cells and batteries by air.
---------------------------------------------------------------------------

    \24\ UN3480, Lithium ion batteries, UN3481, Lithium ion 
batteries, contained in equipment, UN3090, Lithium metal battery 
including lithium alloy batteries, and UN3091, Lithium metal 
batteries packed with/contained in equipment.
---------------------------------------------------------------------------

E. Part 178

Section 178.37
    Section 178.37 outlines the construction requirements for DOT 
specification 3AA and 3AAX seamless steel cylinders. As summarized in 
the Section IV. Section-by-Section Review discussion of changes to 
Sec.  171.7, PHMSA proposes to incorporate by reference the revised 
third edition (published in 2019) of ISO 9809-1, ``Gas cylinders--
Design, construction and testing of refillable seamless steel gas 
cylinders and tubes--Part 1: Quenched and tempered steel cylinders and 
tubes with tensile strength less than 1100 Mpa.'' Currently, ISO 9809-1 
is referenced in Sec.  178.37 as an approved methodology by which to 
perform bend tests, instead of the required flattening test specified 
in paragraph (j). As currently written, paragraph (j) does not specify 
which edition is authorized, yet multiple editions are incorporated by 
reference in Sec.  171.7. PHMSA aims to make the requirement clearer by 
proposing to authorize use of the most current version of ISO 9809-1 
only. PHMSA reviewed the 2019 version and concludes that the bend test 
provisions in the standard remain a suitable alternative for the 
flattening test provisions of paragraph (j). This clarification will 
improve compliance with the appropriate version of ISO 9809-1 and 
ensure an appropriate level of safety.
Section 178.71
    Section 178.71 prescribes specifications for UN pressure 
receptacles. Several updates to referenced standards pertaining to the 
design, construction, and maintenance of UN pressure receptacles were 
added in the 22nd revised edition of the UN Model Regulations. To 
maintain consistency with the UN Model Regulations, PHMSA proposes 
similar updates to those ISO standards incorporated by reference in 
this section.
    Paragraph (f) outlines required conformance to ISO design and 
construction standards, as applicable, for UN refillable welded 
cylinders and UN pressure drums in addition to the general requirements 
of the section. ISO 21172-1:2015, ``Gas cylinders--Welded steel 
pressure drums up to 3,000 litres capacity for the transport of gases--
Design and constructionmdash;Part 1: Capacities up to 1,000 litres'' is 
currently included in paragraph (f)(4) and specifies the minimum 
requirements for the material, design, fabrication, construction and 
workmanship, inspection, and testing at manufacture of refillable 
welded steel pressure drums of volumes up to 1,000 L (264 gallons). The 
22nd revised edition of the UN Model Regulations includes an amendment 
to ISO 21172:2015--ISO 21172-1:2015/Amd1:2018, ``Gas cylinders--Welded

[[Page 34592]]

steel pressure drums up to 3,000 litres capacity for the transport of 
gases--Design and construction--Part 1: Capacities up to 1,000 litres--
Amendment 1.'' ISO 21172-1:2015/Amd1:2018 is a short supplemental 
amendment to be used in conjunction with ISO 21172-1:2015. It removes 
the restriction on use of UN pressure drums for transportation of 
corrosive materials. In addition to adding a reference for use of this 
supplemental document, the UN Model Regulations added a phase out date 
of manufacture of December 31, 2026, until which ISO 21172-1:2015 UN 
pressure drums may continue to be manufactured without the supplement. 
Similarly, PHMSA proposes to require conformance of UN pressure drums 
with ISO 21172 used in combination with the supplemental amendment, and 
adding a phaseout date of December 31, 2026, for continued manufacture 
of UN pressure drums in conformance with ISO 21172-1:2015 without the 
supplemental amendment.
    Additionally, PHMSA proposes to revise paragraphs (g), (k), and (n) 
which outline the design and construction requirements for UN 
refillable seamless steel cylinders, UN acetylene cylinders, and UN 
cylinders for the transportation of adsorbed gases, respectively. 
Currently this section requires that these UN cylinders conform to the 
second edition (published in 2010) of one or more of following ISO 
standards:
    (1) ISO 9809-1:2010 ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1,100 MPa.'';
    (2) ISO 9809-2, ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1,100 MPa.''.
    (3) ISO 9809-3, ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 3: Normalized steel 
cylinders.''
    This series of ISO standards specifies minimum requirements for the 
material, design, construction and workmanship, manufacturing 
processes, examination, and testing at time of manufacture for 
refillable seamless steel gas cylinders and tubes with water capacities 
up to and including 450 L (119 gallons). PHMSA proposes to modify the 
design and construction requirements for UN cylinders by authorizing 
the use of the revised third edition of ISO 9809, Parts 1 through 3. 
Additionally, PHMSA proposes to add a phaseout date of December 31, 
2026, for continued design, construction, and testing of UN cylinders 
conforming to the second edition. Finally, PHMSA proposes to remove 
reference to the first edition of these standards as the authorized 
date (December 31, 2018) for continued manufacture in accordance with 
this edition has expired. PHMSA has reviewed these updated standards as 
part of its regular participation in the review of amendments proposed 
for the UN Model Regulations and expects their required use will 
maintain the HMR safety standard for manufacture of UN cylinders.
    Paragraph (i) outlines required conformance to ISO design and 
construction standards for UN non-refillable metal cylinders. PHMSA 
proposes to remove reference to ISO 11118:1999 and add a reference to a 
supplemental amendment, ISO 11118:2015/Amd 1:2019. Current paragraph 
(i) requires, in addition to the general requirements of the section, 
conformance with ISO 11118:2015, ``Gas cylinders--Non-refillable 
metallic gas cylinders--Specification and test methods.'' ISO 
11118:2015 specifies minimum requirements for the material, design, 
inspections, construction, workmanship, manufacturing processes, and 
tests for manufacture of non-refillable metallic gas cylinders of 
welded, brazed, or seamless construction for compressed and liquefied 
gases including the requirements for their non-refillable sealing 
devices and their methods of testing. PHMSA proposes to revise the 
valve conformance requirements to include a reference to the 2019 
supplemental amendment (ISO 11118:2015/Amd 1:2019), which ISO published 
to be used in conjunction with an ISO 11118:2015. Additionally, PHMSA 
proposes to add an end date of December 31, 2026, to the authorization 
to use ISO 11118:2015 when not used in conjunction with the 
supplemental 2019 amendment, ISO 11118:2015 +Amd.1:2019. This 
supplemental amendment corrects the identity of referenced clauses and 
corrects numerous typographical errors. PHMSA has reviewed this 
supplemental amendment as part of its regular participation in the 
review of amendments proposed for the UN Model Regulations and does not 
expect any degradation of safety standards in association with the use 
of these two documents.
    Paragraph (m) outlines required conformance to ISO standards for 
the design and construction requirements of UN metal hydride storage 
systems. Currently this paragraph requires that metal hydride storage 
systems conform to ISO 16111:2008, ``Transportable gas storage 
devices--Hydrogen absorbed in reversible metal hydride,'' in addition 
to the general requirements of this section. As part of its regular 
review of its existing standards, in 2018 ISO published an updated 
version of this standard, which was adopted in the 22nd revised edition 
of the UN Model Regulations. In addition to permitting construction in 
accordance with ISO 16111:2018, the 22nd revised edition of the UN 
Model Regulations added a December 31, 2026, phaseout date for the 
continued construction of UN metal hydride storage systems conforming 
to ISO 16111:2008. Therefore, to maintain alignment with the UN Model 
Regulations, PHMSA proposes to add the same phaseout date of December 
31, 2026.
    Paragraph (n) prescribes the design and construction requirements 
for UN cylinders for the transportation of adsorbed gases. In addition 
to updating reference for required conformance with ISO 9809-1:2019 as 
discussed above, PHMSA also proposes to require conformance to an 
updated version of ISO 11513, ``Gas cylinders--Refillable welded steel 
cylinders containing materials for sub-atmospheric gas packaging 
(excluding acetylene)--Design, construction, testing, use and periodic 
inspection.'' ISO 11513 specifies minimum requirements for the 
material, design, construction, workmanship, examination and testing at 
manufacture of refillable welded steel cylinders for the sub-
atmospheric pressure storage of liquefied and compressed gases. The 
second edition has updated packing instructions and allows the use of 
ultrasonic testing as a nondestructive method for inspection of the 
cylinders. Currently the HMR require that UN cylinders that are used 
for the transportation of adsorbed gases conform to either ISO 9809-
1:2010 or ISO 11513:2011. PHMSA proposes to require conformance with 
the updated ISO 11513:2019 in addition to the option of the updated ISO 
9809-1:2019 edition. PHMSA also proposes to add a phaseout date of 
December 31, 2026, to allow UN cylinders to continue to be built in 
conformance with ISO 11513:2011.
    Updating reference to this standard would align the HMR with 
changes adopted in the 22nd revised edition of the UN Model 
Regulations, pertaining to the design and construction of UN cylinders 
used for the transportation of adsorbed gases. PHMSA has reviewed this 
edition as part of its regular participation in the review of 
amendments proposed for the UN Model Regulations and expects that the 
required use will maintain the HMR

[[Page 34593]]

safety standard for the manufacture of UN cylinders.
Section 178.75
    Section 178.75 prescribes specifications for multiple-element gas 
containers (MEGCs), which are assemblies of UN cylinders, tubes, or 
bundles of cylinders interconnected by a manifold and assembled within 
a framework. PHMSA proposes to revise paragraph (d)(3) which outlines 
the general design and construction requirements for MEGCs. Currently 
this paragraph requires that each pressure receptacle of a MEGC be of 
the same design type, seamless steel, and constructed and tested 
according to one of five ISO standards including the second editions 
of:
    (1) ISO 9809-1 ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1100 MPa.'';
    (2) ISO 9809-2, ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1100 MPa.''; and
    (3) ISO 9809-3, ``Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction and testing--Part 3: Normalized steel 
cylinders.''
    This series of ISO standards specify minimum requirements for the 
material, design, construction, workmanship, manufacturing processes, 
examination, and testing at time of manufacture for refillable seamless 
steel gas cylinders and tubes with water capacities up to and including 
450 L (119 gallons). The standards were updated and revised, as 
discussed in the Section IV. Section-by-Section Review discussion of 
Sec.  171.7 changes. PHMSA proposes to authorize the use of the third 
edition of ISO 9809, Parts 1 through 3, and to add a phaseout date of 
December 31, 2026, for continued manufacture of pressure receptacles 
using the second edition. Finally, PHMSA proposes to remove reference 
to the first edition of these standards, as the authorization date 
(December 31, 2018) for continued manufacture in accordance with this 
edition has expired. Authorizing the use of these updated references to 
this document would align the HMR with changes adopted in the 22nd 
revised edition of the UN Model Regulations, pertaining to the design 
and construction of pressure vessels, including MEGCs, while 
maintaining the HMR safety standard for use of MEGCs.
Section 178.609
    Section 178.609 provides test requirements for packagings intended 
for transport of infectious substances. PHMSA proposes an editorial 
change in paragraph (d) to clarify the drop testing requirements for 
these packagings. In rule HM-215P,\25\ PHMSA made editorial changes in 
paragraph (g) to clarify the performance requirements for packagings 
intended to also contain dry ice consistent with changes to the 21st 
revised edition of UN Model Regulations. However, some additional 
editorial changes regarding the drop test requirements for these 
packagings were later added to the UN Model Regulations that were not 
reflected in HM-215P. Therefore, in this NPRM, PHMSA proposes to make 
additional editorial corrections to this section pertaining to the drop 
test requirements in paragraph (d). Currently, paragraph (d)(2) states 
that where the samples are in the shape of a drum, three samples must 
be dropped, in three different orientations. However, during the course 
of the finalization of these changes in the UN Model Regulations, an 
additional precision was made regarding the word ``chime,'' which was 
removed from these testing requirements and replaced with the word 
``edge.'' The wording was changed so as not to specify which direction 
the package should be dropped. PHMSA does not consider this change to 
be technical, but editorial, with the intent of conveying the testing 
protocol, as it was designed, more clearly. For that reason, PHMSA 
expects this change to maintain the current level of safety for 
packagings intended to contain infectious substances. This change would 
simply result in a packaging being tested in line with the design of 
the original packaging test method.
---------------------------------------------------------------------------

    \25\ 87 FR 44944 (July 26, 2022).
---------------------------------------------------------------------------

Section 178.706
    Section 178.706 prescribes construction standards for rigid plastic 
IBCs. PHMSA proposes to revise paragraph (c)(3) to allow the use of 
recycled plastic (i.e., used material) in the construction of rigid 
plastic IBCs with the approval of the Associate Administrator 
consistent with a similar change adopted in the 22nd revised edition of 
the UN Model Regulations and international standards. PHMSA proposes 
including a slight variation from the international provision by 
requiring prior approval by the Associate Administrator for use of 
recycled plastics in the construction of rigid plastic IBCs. This 
approach is consistent with current requirements for the construction 
of plastic drums and jerricans in Sec.  178.509(b)(1) that restrict use 
of ``used material'' unless approved by the Associate Administrator. 
The UN Model Regulations incorporate quality assurance program 
requirements that require recognition by a governing body. By requiring 
approval of the Associate Administrator, PHMSA is able to maintain 
oversight of procedures, such as batch testing, that manufacturers will 
use to ensure the quality of recycled plastics used in the construction 
of rigid plastic IBCs. This proposed action will facilitate 
environmentally friendly processes in the construction of rigid plastic 
IBCs while maintaining the high safety standards in the production of 
these packagings for use in transportation of hazardous materials.
Section 178.707
    Section 178.707 prescribes construction standards for composite 
IBCs. PHMSA proposes to revise paragraph (c)(3)(iii) to allow the use 
of recycled plastic (i.e., used material) in the construction of inner 
receptacles of composite IBCs, with the approval of the Associate 
Administrator, consistent with a similar change adopted in the 22nd 
revised edition of the UN Model Regulations and the model international 
standards. PHMSA is including a slight variation from the international 
provision by requiring prior approval by the Associate Administrator to 
use recycled plastics in the construction of inner plastic receptacles 
of composite IBCs. This approach is consistent with current 
requirements for construction of plastic drums and jerricans in Sec.  
[thinsp]178.509(b)(1), which restrict use of ``used material,'' unless 
approved by the Associate Administrator. The UN Model Regulations 
incorporate quality assurance program requirements that require 
recognition by a governing body. By requiring approval of the Associate 
Administrator, PHMSA is able to maintain oversight of procedures, such 
as batch testing, that manufacturers will use to ensure the quality of 
recycled plastics used in the construction of inner plastic receptacles 
of composite IBCs. This proposed action will facilitate environmentally 
friendly processes in the construction of composite IBCs while 
maintaining the high safety standards in the production of these 
packagings for use in transportation of hazardous materials.

F. Part 180

Section 180.207
    Section 180.207 outlines the requirements for requalification of UN

[[Page 34594]]

pressure receptacles. The 22nd revised edition of the UN Model 
Regulations includes numerous updates to referenced standards for 
inspection and maintenance of UN pressure receptacles. PHMSA proposes 
similar amendments in the HMR to maintain consistency with the UN Model 
Regulations. To that end, PHMSA proposes to revise paragraph (d), which 
specifies the requalification procedures and conformance standards for 
specific procedures. Specifically, paragraph (d)(3) currently requires 
that dissolved acetylene UN cylinders be requalified in accordance with 
ISO 10462:2013, ``Gas cylinders--Acetylene cylinders--Periodic 
inspection and maintenance. ISO 10462:2013 specifies requirements for 
the periodic inspection and maintenance of acetylene cylinders. It 
applies to acetylene cylinders with and without solvent and with a 
maximum nominal water capacity of 150 L. As part of a periodic review 
of its standards, the ISO reviewed this standard, and in June 2019 
published a short supplemental amendment, ISO 10462:2013/Amd 1:2019. 
The supplemental document provides amendments that simplify the marking 
of rejected cylinders to render them unserviceable. This supplemental 
document is intended for use in conjunction with ISO 10462:2013 for the 
periodic inspection and maintenance of dissolved acetylene UN 
cylinders. As such, PHMSA proposes to add a reference to ISO 
10462:2013/Amd 1:2019 in Sec.  180.207(d)(3) where ISO 10462:2013 is 
currently required, and add a phaseout date of December 31, 2024, for 
authorized use of ISO 10462:2013 without the supplemental amendment.
    PHMSA also proposes to revise paragraph (d)(5) which requires that 
UN cylinders used for adsorbed gases be inspected and tested in 
accordance with Sec.  173.302c and ISO 11513:2011. ISO 11513 specifies 
minimum requirements for the material, design, construction, 
workmanship, examination and testing at manufacture of refillable 
welded steel cylinders for the sub-atmospheric pressure storage of 
liquefied and compressed gases. The 22nd revised edition of the UN 
Model Regulations updated references to ISO 11513 to authorize the use 
of the second edition, ISO 11513:2019. This second edition has been 
updated to amend packing instructions and remove the prohibition on the 
use of ultrasonic testing during periodic inspection. PHMSA proposes 
authorizing the use of ISO 11513:2019 and adding a sunset date of 
December 31, 2024, until which the current edition of ISO 11513 may 
continue to be used.
    Lastly, PHMSA proposes to add paragraph (d)(8) to reference ISO 
23088:2020, ``Gas cylinders--Periodic inspection and testing of welded 
steel pressure drums--Capacities up to 1,000 L,'' to provide a 
requalification standard for UN pressure drums because requalification 
procedures may differ for pressure drums versus other UN pressure 
receptacles. The ISO 23088:2020 standard complements the design and 
construction standard ISO 21172-1, ``Gas cylinders--Welded steel 
pressure drums up to 3,000 litre capacity for the transport of gases--
Design and construction--Part 1: Capacities up to 1,000 litres'', 
referenced in Sec.  178.71 for UN pressure drums. ISO 21172-1:2015 was 
added in the HMR in rule HM-215O. PHMSA expects that incorporating by 
reference a safety standard for requalification will reduce business 
costs and environmental effects by allowing existing UN pressure drums 
to be reintroduced into service for continued use for an extended 
period of time.
    These revisions would align the HMR with changes adopted in the 
22nd revised edition of the UN Model Regulations pertaining to industry 
consensus standards for requalification and maintenance procedures for 
UN pressure receptacles. PHMSA has reviewed this edition as part of its 
regular participation in the review of amendments proposed for the UN 
Model Regulations and does not expect any degradation of safety 
standards in association with its use. PHMSA expects that these 
amendments will enhance safety by providing cylinder and pressure drum 
users with the necessary guidelines for the continued use of UN 
pressure receptacles.

VI. Regulatory Analyses and Notices

A. Statutory/Legal Authority for This Rulemaking

    This NPRM is published under the authority of Federal Hazardous 
Materials Transportation Law. Section 5103(b) authorizes the Secretary 
of Transportation to prescribe regulations for the safe transportation, 
including security, of hazardous materials in intrastate, interstate, 
and foreign commerce. Additionally, 49 U.S.C. 5120 authorizes the 
Secretary to consult with interested international authorities to 
ensure that, to the extent practicable, regulations governing the 
transportation of hazardous materials in commerce are consistent with 
the standards adopted by international authorities. The Secretary has 
delegated the authority granted in the Federal Hazardous Materials 
Transportation Law to the PHMSA Administrator at 49 CFR 1.97(b).

B. Executive Order 12866 and DOT Regulatory Policies and Procedures

    Executive Order 12866 (``Regulatory Planning and Review'') \26\ 
requires agencies to regulate 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.'' Similarly, DOT Order 2100.6A 
(``Policies and Procedures for Rulemakings'') requires that PHMSA 
rulemaking actions include ``an assessment of the potential benefits, 
costs, and other important impacts of the regulatory action,'' and (to 
the extent practicable) the benefits, costs, and any significant 
distributional impacts, including any environmental impacts.
---------------------------------------------------------------------------

    \26\ 58 FR 51735 (Oct. 4, 1993).
---------------------------------------------------------------------------

    Executive Order 12866 and DOT Order 2100.6A require that PHMSA 
submit ``significant regulatory actions'' to the Office of Management 
and Budget (OMB) for review. This rulemaking is not considered a 
significant regulatory action under section 3(f) of Executive Order 
12866 and, therefore, was not formally reviewed by OMB. This rulemaking 
is also not considered a significant rule under DOT Order 2100.6A.
    The following is a brief summary of costs, savings, and net 
benefits of some of the amendments proposed in this notice. PHMSA has 
developed a more detailed analysis of these costs and benefits in the 
preliminary regulatory impact analysis (PRIA), a copy of which has been 
placed in the docket. PHMSA seeks public comment on its proposed 
revisions to the HMR and the preliminary cost and benefit analyses in 
the PRIA.
    PHMSA proposes to amend the HMR to maintain alignment with 
international regulations and standards, thereby maintaining the high 
safety standard currently achieved under the HMR, facilitating the safe 
transportation of, and aligning HMR requirements with, anticipated 
increases in the volume of lithium batteries transported by interstate 
commerce from electrification of the transportation and other economic 
sectors. PHMSA examined the likely impacts of finalizing and 
implementing the provisions proposed in the NPRM in order to assess the 
benefits and costs of these amendments. This analysis allowed PHMSA to 
quantitatively assess the material effects of four of the

[[Page 34595]]

proposed amendments in the rulemaking. The effects of six remaining 
proposed amendments are not quantified but are assessed qualitatively.
    PHMSA estimates that the net annualized quantified net cost savings 
of this rulemaking, using a 7% discount rate, are between $5.5 million 
and $13.2 million per year. The following table presents a summary of 
the monetized impacts that these proposed changes may have upon 
codification.

                                                              Summary of Net Regulatory Cost Savings, Discount Rate = 7%, 2022-2031
                                                                                        [millions, 2021$]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  10 Year costs     10 Year cost savings    10 Year net cost        Annual costs       Annual cost savings     Annual net cost
                                                             --------------------------------------------        savings       --------------------------------------------        savings
                       Rule amendment                                                                    ----------------------                                            ---------------------
                                                                 Low        High       Low        High       Low        High       Low        High       Low        High       Low        High
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1: Incorporation by reference...............................         $8         $8         $0         $0       $(8)       $(8)         $1         $1         $0         $0       $(1)       $(1)
2: HMT additions............................................        0.1        0.1          0          0      (0.1)      (0.1)       0.01       0.01          0          0     (0.01)     (0.01)
3: Self-reactive materials and organic peroxides............          0          0       0.01       0.03       0.01       0.03          0          0      0.001      0.005      0.001      0.005
5: Lithium battery changes..................................          4          7         54        105         47        101        0.5          1          8         15          7         14
                                                             -----------------------------------------------------------------------------------------------------------------------------------
    Total...................................................       12.1       15.0       53.9      104.8       38.9       92.8        1.7        2.1        7.7       14.9        5.5       13.2
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Values in red in net cost savings columns indicate costs. Low net cost savings for each amendment are determined by subtracting the highest costs from the lowest cost savings. High net
  cost savings are determined by subtracting the lowest costs from the highest cost savings.

    The safety and environmental benefits of the proposed rule have not 
been quantified. However, PHMSA expects the proposed amendments would 
help to improve public safety and reduce the risk of environmental harm 
by maintaining consistency between these international regulations and 
the HMR. Harmonization of the HMR with international consensus 
standards as proposed could reduce delays and interruptions of 
hazardous materials during transportation, thereby lowering GHG 
emissions and safety risks to communities (including minority, low 
income, underserved, and other disadvantaged populations and 
communities) in the vicinity of interim storage sites and 
transportation arteries and hubs.

C. Executive Order 13132

    PHMSA analyzed this rulemaking in accordance with the principles 
and criteria contained in Executive Order 13132 (``Federalism'') \27\ 
and the Presidential memorandum (``Preemption'') that was published in 
the Federal Register on May 22, 2009.\28\ Executive Order 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.''
---------------------------------------------------------------------------

    \27\ 64 FR 43255 (Aug. 10, 1999).
    \28\ 74 FR 24693 (May 22, 2009).
---------------------------------------------------------------------------

    The rulemaking may preempt state, local, and Native American tribe 
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. The Federal 
Hazardous Materials Transportation Law contains an express preemption 
provision at 49 U.S.C. 5125(b) that preempts state, local, and tribal 
requirements on certain covered subjects, unless the non-federal 
requirements are ``substantively the same'' as the federal 
requirements, including the following:
    (1) The designation, description, and classification of hazardous 
material;
    (2) The packing, repacking, handling, labeling, marking, and 
placarding of hazardous material;
    (3) The preparation, execution, and use of shipping documents 
related to hazardous material and requirements related to the number, 
contents, and placement of those documents;
    (4) The written notification, recording, and reporting of the 
unintentional release in transportation of hazardous material; and
    (5) The design, manufacture, fabrication, inspection, marking, 
maintenance, recondition, repair, or testing of a packaging or 
container represented, marked, certified, or sold as qualified for use 
in transporting hazardous material in commerce.
    This proposed rule addresses covered subject items (1), (2), (3), 
(4), and (5) above and would preempt state, local, and tribal 
requirements not meeting the ``substantively the same'' standard. In 
this instance, the preemptive effect of the proposed rule is limited to 
the minimum level necessary to achieve the objectives of the hazardous 
materials transportation law under which the final rule is promulgated. 
Therefore, the consultation and funding requirements of Executive Order 
13132 do not apply.

D. Executive Order 13175

    PHMSA analyzed this rulemaking in accordance with the principles 
and criteria contained in Executive Order 13175 (``Consultation and 
Coordination with Indian Tribal Governments'') \29\ and DOT Order 
5301.1 (``Department of Transportation Policies, Programs, and 
Procedures Affecting American Indians, Alaska Natives, and Tribes''). 
Executive Order 13175 and DOT Order 5301.1 require DOT Operating 
Administrations to assure meaningful and timely input from Native 
American 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 Native American tribes.
---------------------------------------------------------------------------

    \29\ 65 FR 67249 (Nov. 9, 2000).
---------------------------------------------------------------------------

    PHMSA assessed the impact of the rulemaking and preliminarily 
determined that it would not significantly or uniquely affect tribal 
communities or Native American tribal governments. The changes to the 
HMR proposed in this NPRM are facially neutral and would have broad, 
national scope; PHMSA, therefore, expects this rulemaking to not 
significantly or uniquely affect tribal communities, much less impose 
substantial compliance costs on Native American tribal governments or 
mandate tribal action. And because PHMSA expects the rulemaking would 
not adversely affect the safe transportation of hazardous materials 
generally, PHMSA does not expect it would entail disproportionately 
high adverse risks for tribal communities. For these reasons, PHMSA 
does not expect the funding and consultation requirements of Executive 
Order 13175 and DOT Order 5301.1 to apply. However, PHMSA solicits 
comment from Native American tribal governments and communities on 
potential impacts of the proposed rulemaking.

[[Page 34596]]

E. Regulatory Flexibility Act and Executive Order 13272

    The Regulatory Flexibility Act (5 U.S.C. 601, et seq.) requires 
agencies to review proposed regulations to assess their impact on small 
entities, unless the agency head certifies that a proposed rulemaking 
will not have a significant economic impact on a substantial number of 
small entities, including small businesses, not-for-profit 
organizations that are independently owned and operated and are not 
dominant in their fields, and governmental jurisdictions with 
populations under 50,000. The Regulatory Flexibility Act directs 
agencies to establish exceptions and differing compliance standards for 
small businesses, where possible to do so and still meet the objectives 
of applicable regulatory statutes. Executive Order 13272 (``Proper 
Consideration of Small Entities in Agency Rulemaking'') \30\ 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. The DOT posts its implementing guidance on a dedicated 
web page.\31\
---------------------------------------------------------------------------

    \30\ 67 FR 53461 (Aug. 16, 2002).
    \31\ DOT, ``Rulemaking Requirements Related to Small Entities,'' 
www.transportation.gov/regulations/rulemaking-requirements-concerning-small-entities.
---------------------------------------------------------------------------

    This proposed rulemaking has been developed in accordance with 
Executive Order 13272 and with DOT's procedures and policies to promote 
compliance with the Regulatory Flexibility Act to ensure that potential 
impacts of draft rules on small entities are properly considered. This 
proposed rule facilitates the transportation of hazardous materials in 
international commerce by providing consistency with international 
standards. It applies to offerors and carriers of hazardous materials, 
some of whom are small entities, such as chemical manufacturers, users, 
and suppliers, packaging manufacturers, distributors, and training 
companies. As discussed at length in the PRIA found in the rulemaking 
docket, the amendments in this proposed rule should result in net cost 
savings that would ease the regulatory compliance burden for those and 
other entities engaged in domestic and international commerce, 
including trans-border shipments within North America. Additionally, 
the changes proposed in this NPRM would relieve U.S. companies, 
including small entities competing in foreign markets, from the burden 
of complying with a dual system of regulations. Therefore, PHMSA 
expects that these amendments will not, if adopted, have a significant 
economic impact on a substantial number of small entities. However, 
PHMSA solicits comments on the anticipated economic impacts to small 
entities.

F. Paperwork Reduction Act

    Under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501, et 
seq.), no person is required to respond to an information collection 
unless it has been approved by OMB and displays a valid OMB control 
number. Pursuant to 44 U.S.C. 3506(c)(2)(B) and 5 CFR 1320.8(d), PHMSA 
must provide interested members of the public and affected agencies 
with an opportunity to comment on information collection and 
recordkeeping requests.
    PHMSA has analyzed this NPRM in accordance with the Paperwork 
Reduction Act. PHMSA currently accounts for shipping paper burdens 
under OMB Control Number 2137-0034, ``Hazardous Materials Shipping 
Papers and Emergency Response Information.'' PHMSA proposes some 
amendments that may impact OMB Control Number 2137-0034, such as the 
requirement to indicate the use of Special Provisions A54 on the 
shipping papers, however PHMSA expects the overall impact to annual 
paperwork burden is negligible in relation to the number of burden 
hours currently associated with this information collection. While 
PHMSA expects this proposal to reduce the burden associated with this 
information collection, PHMSA anticipates the reduction is negligible 
in relation to the total burden hours associated with special permit 
applications.
    Additionally, PHMSA is revising Sec.  173.185(c)(4) to require that 
shippers and carriers of small lithium batteries not contained in 
equipment have shipping papers and perform NOPIC checks when 
transported by air. PHMSA estimates that 45 domestic airlines 
transporting 4,044 shipments of affected lithium batteries may be 
affected by this provision. PHMSA estimates a burden increase of 16 
minutes per shipment, or 64,704 minutes (1,078 hours) in the first 
year. PHMSA estimates the increased burden for this information 
collection as follows:

OMB Control No. 2137-0034: Hazardous Materials Shipping Papers & 
Emergency Response Information
Annual increase in number of respondents: 45.
Annual increase in number of responses: 4,044.
Annual increase in burden hours: 1,078.
Increase in Annual Burden Cost: $0.

    PHMSA accounts for the burden from approval applications in OMB 
Control Number 2137-0557, ``Approvals for Hazardous Materials.'' PHMSA 
also proposes to add new entries to the Sec.  173.224 Self Reactives 
Table and Sec.  173.225 Organic Peroxide Table, which PHMSA expects 
estimates would decrease the number of annual approval applicants. 
However, PHMSA expects that these proposed changes are negligible to 
the overall impact of the total burden, in relation to the number of 
burden hours associated with this information collection. Based on 
estimates provided in the PRIA, PHMSA estimates that this proposal 
would reduce the number of approvals by one annually. PHMSA estimates 
the reduction in this information collection as follows:
OMB Control No. 2137-0057: Approvals for Hazardous Materials
Decrease in Annual Number of Respondents: 1
Decrease in Annual Responses: 1
Decrease in Annual Burden Hours: 4.75
Decrease in Annual Burden Cost: $0

    PHMSA requests comments on the information collection and 
recordkeeping burdens associated with developing, implementing, and 
maintaining the proposed requirements in this NPRM. Address written 
comments to the DOT Docket Operations Office identified in the 
ADDRESSES section of this rulemaking. PHMSA must receive comments 
regarding information collection burdens prior to the close of the 
comment period identified in the DATES section of this rulemaking. 
Requests for a copy of this information collection should be directed 
to Steven Andrews, Standards and Rulemaking Division (PHH-10), Pipeline 
and Hazardous Materials Safety Administration, 1200 New Jersey Avenue 
SE, Washington, DC 20590-0001. If these proposed requirements are 
adopted in a final rule, PHMSA will submit the revised information 
collection and recordkeeping requirements to OMB for approval.

G. Unfunded Mandates Reform Act of 1995

    The Unfunded Mandates Reform Act of 1995 (UMRA; 2 U.S.C. 1501, et 
seq.) requires agencies to assess the effects of federal regulatory 
actions on state, local, and tribal governments, and the private 
sector. For any NPRM or final rule that includes a federal mandate that 
may result in the expenditure by state, local, and tribal governments, 
or by the

[[Page 34597]]

private sector, of $100 million or more in 1996 dollars in any given 
year, the agency must prepare, amongst other things, a written 
statement that qualitatively and quantitatively assesses the costs and 
benefits of the federal mandate.
    As explained in the PRIA, this proposed rulemaking does not impose 
unfunded mandates under the UMRA. It is not expected to result in costs 
of $100 million or more in 1996 dollars to either state, local, or 
tribal governments, or to the private sector, in any one year. A copy 
of the PRIA is available for review in the docket.

H. Environmental Assessment

    The National Environmental Policy Act of 1969 (NEPA; 42 U.S.C. 
4321, et seq.), requires that federal agencies analyze proposed actions 
to determine if the action would have a significant impact on the human 
environment. The Council on Environmental Quality implementing 
regulations (40 CFR, parts 1500-1508) require federal agencies to 
conduct an environmental review considering (1) the need for the 
action, (2) alternatives to the action, (3) probable environmental 
impacts of the action and alternatives, and (4) the agencies and 
persons consulted during the consideration process. DOT Order 5610.1C 
(``Procedures for Considering Environmental Impacts'') establishes 
departmental procedures for evaluation of environmental impacts under 
NEPA and its implementing regulations. This Environmental Assessment 
incorporates by reference the analysis discussing safety impacts that 
is included in the preamble language above.
1. Purpose and Need
    This NPRM would amend the HMR to maintain alignment with 
international consensus standards by incorporating into the HMR various 
amendments, including changes to proper shipping names, hazard classes, 
packing groups, special provisions, packaging authorizations, air 
transport quantity limitations, and vessel stowage requirements. PHMSA 
notes that the amendments proposed in this NPRM are intended to result 
in cost savings and reduced regulatory burden for shippers engaged in 
domestic and international commerce, including trans-border shipments 
within North America. Absent adoption of the amendments proposed in the 
NPRM, U.S. companies--including numerous small entities competing in 
foreign markets--may be at an economic disadvantage because of their 
need to comply with a dual system of regulations. Further, among the 
HMR amendments introduced in this rulemaking are those aligning HMR 
requirements with anticipated increases in the volume of lithium 
batteries transported in interstate commerce, from electrification of 
the transportation and other economic sectors.
    As explained at greater length above in the preamble of this NPRM 
and in the PRIA (each of which is incorporated by reference in this 
discussion of the environmental impacts of the Proposed Action 
Alternative), PHMSA expects that the adoption of the regulatory 
amendments proposed in this NPRM would maintain the high safety 
standard currently achieved under the HMR. PHMSA has evaluated the 
safety of each of the amendments proposed in this NPRM on its own 
merit, as well as the aggregate impact on transportation safety from 
adoption of those amendments.
2. Alternatives
    In proposing this rulemaking, PHMSA is considering the following 
alternatives:
No Action Alternative
    If PHMSA were to select the No Action Alternative, current 
regulations would remain in place and no provisions would be amended or 
added.
Proposed Action Alternative
    This alternative is the current proposal as it appears in this 
NPRM, applying to transport of hazardous materials by various transport 
modes (highway, rail, vessel, and aircraft). The proposed amendments 
included in this alternative are more fully discussed in the preamble 
and regulatory text sections of this NPRM.
3. Reasonably Foreseeable Environmental Impacts of the Alternatives
No Action Alternative
    If PHMSA were to select the No Action Alternative, the HMR would 
remain unchanged, and no provisions would be amended or added. However, 
any economic benefits gained through harmonization of the HMR with 
updated international consensus standards (including, but not limited 
to, the 22nd revised edition of the UN Model Regulations, the 2023-2024 
ICAO Technical Instructions and amendment 41-22 of the IMDG Code) 
governing shipping of hazardous materials would not be realized.
    Additionally, the No Action Alternative would not adopt enhanced 
and clarified regulatory requirements expected to maintain the high 
level of safety in transportation of hazardous materials provided by 
the HMR. As explained in the preamble to the NPRM, consistency between 
the HMR and current international standards can enhance safety by (1) 
ensuring that the HMR is informed by the latest best practices and 
lessons learned; (2) improving understanding of, and compliance with, 
pertinent requirements; (3) enabling consistent emergency response 
procedures in the event of a hazardous materials incident; and (4) 
facilitating the smooth flow of hazardous materials from their points 
of origin to their points of destination, thereby avoiding risks to the 
public and the environment from release of hazardous materials from 
delays or interruptions in the transportation of those materials. PHMSA 
would not capture those benefits if it were to pass on incorporating 
updated international standards into the HMR under the No Action 
Alternative.
    PHMSA expects that the No Action Alternative could have a modest 
impact on GHG emissions. Because PHMSA expects that the differences 
between the HMR and international standards for transportation of 
hazardous materials could result in transportation delays or 
interruptions, PHMSA anticipates that there could be modestly higher 
GHG emissions from some combination of (1) transfer of delayed 
hazardous materials to and from interim storage, (2) return of 
improperly shipped materials to their point of origin, and (3) 
reshipment of returned materials. PHMSA notes that it is unable to 
quantify such GHG emissions because of the difficulty in identifying 
the precise quantity or characteristics of such interim storage or 
returns/re-shipments. PHMSA also submits that, as explained at greater 
length in Section IV.J., to the extent that there are any delays 
arising from inconsistencies between the HMR and recently updated 
international standards, there could also be adverse impacts from the 
No Action Alternative for minority populations, low-income populations, 
or other underserved and other disadvantaged communities.
Proposed Action Alternative
    As explained further in the discussions in each of the No Action 
Alternative above, the preamble, and the PRIA, PHMSA anticipates the 
changes proposed under the Proposed Action Alternative will maintain 
the high safety standards currently achieved under the HMR. 
Harmonization of the HMR with updated international consensus standards 
is also expected to capture economic efficiencies gained from avoiding 
shipping delays and compliance costs associated with having

[[Page 34598]]

to comply with divergent U.S. and international regulatory regimes for 
transportation of hazardous materials. Further, PHMSA expects revision 
of the HMR as proposed in the NPRM will accommodate safe transportation 
of emerging technologies (in particular components of lithium battery 
technologies) and facilitate safe shipment of hazardous materials.
    PHMSA expects that the Proposed Action Alternative could realize 
modest reductions in GHG emissions. Because PHMSA expects that the 
differences between the HMR and international standards for 
transportation of hazardous materials could result in delays or 
interruptions, PHMSA anticipates that the No Action Alternative could 
result in modestly higher GHG emissions from some combination of (1) 
transfer of delayed hazardous materials to and from interim storage, 
(2) return of improperly shipped materials to their point of origin, or 
(3) reshipment of returned materials. The Proposed Action Alternative 
avoids those risks resulting from divergence of the HMR from updated 
international standards. PHMSA notes, however, that it is unable to 
quantify any GHG emissions benefits because of the difficulty in 
identifying the precise quantity or characteristics of such interim 
storage or returns/re-shipments. Lastly, PHMSA also submits that, as 
explained at greater length in Section IV.J., the Proposed Action 
Alternative would avoid any delayed or interrupted shipments arising 
from the divergence of the HMR from updated international standards 
under the No Action Alternative that could result in adverse impacts 
for minority populations, low-income populations, or other underserved 
and other disadvantaged communities.
4. Agencies Consulted
    PHMSA has coordinated with FAA, FMCSA, FRA, and USCG in the 
development of this proposed rule. PHMSA solicits, and will consider, 
comments on the NPRM's potential impacts on the human environment 
submitted by members of the public, state, and local governments, 
tribal communities, and industry.
5. Proposed Finding of No Significant Impact
    PHMSA expects the adoption of the Proposed Action Alternative's 
regulatory amendments will maintain the HMR's current high level of 
safety for shipments of hazardous materials transported by highway, 
rail, aircraft, and vessel, and as such finds the HMR amendments in the 
NPRM would have no significant impact on the human environment. PHMSA 
expects that the Proposed Action Alternative will avoid adverse safety, 
environmental justice, and GHG emissions impacts of the No Action 
Alternative. Furthermore, based on PHMSA's analysis of these provisions 
described above, PHMSA proposes to find that codification and 
implementation of this rule would not result in a significant impact to 
the human environment.
    PHMSA welcomes any views, data, or information related to 
environmental impacts that may result from NPRM's proposed 
requirements, the No Action Alternative, and other viable alternatives 
and their environmental impacts.

I. Environmental Justice

    DOT Order 5610.2C (Department of Transportation Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations'') and Executive Orders 12898 (``Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations''),\32\ 13985 (``Advancing Racial Equity and Support for 
Underserved Communities Through the Federal Government''),\33\ 13990 
(``Protecting Public Health and the Environment and Restoring Science 
To Tackle the Climate Crisis''),\34\ and 14008 (``Tackling the Climate 
Crisis at Home and Abroad'') \35\ require DOT agencies to achieve 
environmental justice as part of their mission by identifying and 
addressing, as appropriate, disproportionately high and adverse human 
health or environmental effects, including interrelated social and 
economic effects of their programs, policies, and activities on 
minority populations, low-income populations, and other underserved and 
disadvantaged communities.
---------------------------------------------------------------------------

    \32\ 59 FR 7629 (Feb. 11, 1994).
    \33\ 86 FR 7009 (Jan. 20, 2021).
    \34\ 86 FR 7037 (Jan. 20, 2021).
    \35\ 86 FR 7619 (Feb. 1, 2021).
---------------------------------------------------------------------------

    PHMSA has evaluated this proposed rule under the above Executive 
Orders and DOT Order 5610.2C. PHMSA does not expect the proposed rule, 
if finalized, to cause disproportionately high and adverse human health 
and environmental effects on minority, low-income, underserved, and 
other disadvantaged populations and communities. The rulemaking is 
facially neutral and national in scope; it is neither directed toward a 
particular population, region, or community, nor is it expected to 
adversely impact any particular population, region, or community. And 
because PHMSA expects the rulemaking would not adversely affect the 
safe transportation of hazardous materials generally, PHMSA does not 
expect that the proposed revisions would entail disproportionately high 
adverse risks for minority populations, low-income populations, or 
other underserved and other disadvantaged communities.
    PHMSA submits that the proposed rulemaking could in fact reduce 
risks to minority populations, low-income populations, or other 
underserved and other disadvantaged communities. Because the proposed 
HMR amendments could avoid the release of hazardous materials and 
reduce the frequency of delays and returned/resubmitted shipments of 
hazardous materials resulting from conflict between the current HMR and 
updated international standards, the proposed rule could reduce risks 
to populations and communities--including any minority, low-income, 
underserved and other disadvantaged populations and communities--in the 
vicinity of interim storage sites and transportation arteries and hubs. 
Additionally, as explained in the above discussion of NEPA, PHMSA 
expects that its proposed HMR amendments will yield modest GHG 
emissions reductions, thereby reducing the risks posed by anthropogenic 
climate change to minority, low-income, underserved, and other 
disadvantaged populations and communities.
    PHMSA solicits comment from minority, low-income, underserved, and 
other disadvantaged populations and communities on potential impacts of 
the proposed rulemaking.

J. Privacy Act

    In accordance with 5 U.S.C. 553(c), DOT solicits comments from the 
public to better inform its rulemaking process. DOT posts these 
comments, without edit and including any personal information that the 
commenter includes, in the system of records notice. DOT's complete 
Privacy Act Statement is in the Federal Register published on April 11, 
2000,\36\ or on DOT's website at http://www.dot.gov/privacy.
---------------------------------------------------------------------------

    \36\ 65 FR 19477 (Apr. 11, 2000).
---------------------------------------------------------------------------

K. Executive Order 13609 and International Trade Analysis

    Executive Order 13609 (``Promoting International Regulatory 
Cooperation'') \37\ requires that agencies consider whether the impacts 
associated with significant variations between domestic and 
international regulatory

[[Page 34599]]

approaches are unnecessary or may impair the ability of American 
business to export and compete internationally. In meeting shared 
challenges involving health, safety, labor, security, environmental, 
and other issues, international regulatory cooperation can identify 
approaches that are at least as protective as those that are or would 
be adopted in the absence of such cooperation. International regulatory 
cooperation can also reduce, eliminate, or prevent unnecessary 
differences in regulatory requirements.
---------------------------------------------------------------------------

    \37\ 77 FR 26413 (May 4, 2012).
---------------------------------------------------------------------------

    Similarly, the Trade Agreements Act of 1979 (Pub. L. 96-39), as 
amended by the Uruguay Round Agreements Act (Pub. L. 103-465) (as 
amended, the Trade Agreements Act), prohibits agencies from 
establishing any standards or engaging in related activities that 
create unnecessary obstacles to the foreign commerce of the United 
States. Pursuant to the Trade Agreements Act, the establishment of 
standards is not considered an unnecessary obstacle to the foreign 
commerce of the United States, so long as the standards have a 
legitimate domestic objective, such as providing for safety, and do not 
operate to exclude imports that meet this objective. The statute also 
requires consideration of international standards and, where 
appropriate, that they be the basis for U.S. standards.
    PHMSA participates in the establishment of international standards 
to protect the safety of the American public, and it has assessed the 
effects of the proposed rule to ensure that it does not cause 
unnecessary obstacles to foreign trade. In fact, the proposed rule is 
expected to facilitate international trade by harmonizing U.S. and 
international requirements for the transportation of hazardous 
materials so as to reduce regulatory burdens and minimize delays 
arising from having to comply with divergent regulatory requirements. 
Accordingly, this rulemaking is consistent with Executive Order 13609 
and PHMSA's obligations under the Trade Agreements Act.

L. National Technology Transfer and Advancement Act

    The National Technology Transfer and Advancement Act of 1995 (15 
U.S.C. 272 note) directs federal agencies to use voluntary consensus 
standards in their regulatory activities, unless doing so would be 
inconsistent with applicable law or otherwise impractical. Voluntary 
consensus standards are technical standards (e.g., specification of 
materials, test methods, or performance requirements) that are 
developed or adopted by voluntary consensus standard bodies. This 
rulemaking involves multiple voluntary consensus standards, which are 
discussed at length in the discussion on Sec.  171.7. See Section 171.7 
of the Section-by-Section Review for further details.

M. Executive Order 13211

    Executive Order 13211 (``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'') \38\ 
requires federal agencies to prepare a Statement of Energy Effects for 
any ``significant energy action.'' Executive Order 13211 defines a 
``significant energy action'' as any action by an agency (normally 
published in the Federal Register) that promulgates, or is expected to 
lead to the promulgation of, a final rule or regulation that (1)(i) is 
a significant regulatory action under Executive Order 12866 or any 
successor order and (ii) is likely to have a significant adverse effect 
on the supply, distribution, or use of energy (including a shortfall in 
supply, price increases, and increased use of foreign supplies); or (2) 
is designated by the Administrator of the Office of Information and 
Regulatory Affairs (OIRA) as a significant energy action.
---------------------------------------------------------------------------

    \38\ 66 FR 28355 (May 22, 2001).
---------------------------------------------------------------------------

    This proposed rule is not a significant action under Executive 
Order 12866, nor is it expected to have an annual effect on the economy 
of $100 million. Further, this action is not expected to have a 
significant adverse effect on the supply, distribution, or use of 
energy in the United States. The Administrator of OIRA has not 
designated the proposed rule as a significant energy action. For 
additional discussion of the anticipated economic impact of this 
rulemaking, please review the PRIA posted in the rulemaking docket.

List of Subjects

49 CFR Part 171

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

49 CFR Part 172

    Education, Hazardous materials transportation, Hazardous waste, 
Incorporation by reference, Labeling, Markings, Packaging and 
containers, Reporting and recordkeeping requirements.

49 CFR Part 173

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

49 CFR Part 175

    Air carriers, Hazardous materials transportation, Incorporation by 
reference, Radioactive materials, Reporting and recordkeeping 
requirements.

49 CFR Part 176

    Cargo vessels, Hazardous materials transportation, Incorporation by 
reference, Maritime carriers, Radioactive materials, Reporting and 
recordkeeping requirements.

49 CFR Part 178

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

49 CFR Part 180

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

    In consideration of the foregoing, PHMSA proposes to amend 49 CFR 
chapter I as follows:

PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS

0
1. The authority citation for part 171 continues to read as follows:

    Authority:  49 U.S.C. 5101-5128, 44701; Pub. L. 101-410 section 
4; Pub. L. 104-134, section 31001; Pub. L. 114-74 section 4 (28 
U.S.C. 2461 note); 49 CFR 1.81 and 1.97.

0
2. In Sec.  171.7:
0
a. Revise paragraphs (t)(1), (v)(2); and (w)(32) through (81);
0
b. Add paragraphs (w)(82) through (92); and
0
c. Revise paragraphs (aa)(3) and (dd)(1) through (4).
    The revisions and additions read as follows:

Sec.  171.7  Reference material.

* * * * *
    (t) * * *
    (1) ICAO Doc 9284 Technical Instructions for the Safe Transport of 
Dangerous Goods by Air (ICAO Technical Instructions), 2023-2024 
Edition, copyright 2021; into Sec. Sec.  171.8; 171.22 through 171.24; 
172.101; 172.202; 172.401; 172.407; 172.512; 172.519; 172.602; 173.56; 
173.320; 175.10, 175.33; 178.3.
* * * * *
    (v) * * *
    (2) International Maritime Dangerous Goods Code (IMDG Code), 
Incorporating

[[Page 34600]]

Amendment 41-22 (English Edition), Volumes 1 and 2, 2022 Edition; into 
Sec. Sec.  171.22; 171.23; 171.25; 172.101; 172.202; 172.203; 172.401; 
172.407; 172.502; 172.519; 172.602; 173.21; 173.56; 176.2; 176.5; 
176.11; 176.27; 176.30; 176.83; 176.84; 176.140; 176.720; 176.906; 
178.3; 178.274.
    (w) * * *
    (32) ISO 9809-1:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 1: 
Quenched and tempered steel cylinders and tubes with tensile strength 
less than 1100 Mpa, Third Edition, 2019-08-01; into Sec. Sec.  178.37; 
178.71; 178.75.
    (33) ISO 9809-2:2000(E): Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1 100 MPa., First edition, June 2000; into Sec. Sec.  178.71; 178.75.
    (34) ISO 9809-2:2010(E): Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 2: Quenched and 
tempered steel cylinders with tensile strength greater than or equal to 
1100 MPa., Second edition, 2010-04-15; into Sec. Sec.  178.71; 178.75.
    (35) ISO 9809-2:2019(E): Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 2: 
Quenched and tempered steel cylinders and tubes with tensile strength 
greater than or equal to 1100 MPa, Third edition, 2019-08; into 
Sec. Sec.  178.71; 178.75.
    (36) ISO 9809-3:2000(E): Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 3: Normalized 
steel cylinders, First edition, December 2000; into Sec. Sec.  178.71; 
178.75.
    (37) ISO 9809-3:2010(E): Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 3: Normalized 
steel cylinders, Second edition, 2010-04-15; into Sec. Sec.  178.71; 
178.75.
    (38) ISO 9809-3:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 3: 
Normalized steel cylinders and tubes, Third edition, 2018-08; into 
Sec. Sec.  178.71; 178.75.
    (39) ISO 9809-4:2014(E), Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 4: Stainless 
steel cylinders with an Rm value of less than 1 100 MPa, First edition, 
2014-07-15; into Sec. Sec.  178.71; 178.75.
    (40) ISO 9978:1992(E)--Radiation protection--Sealed radioactive 
sources--Leakage test methods. First Edition, (February 15, 1992); into 
Sec.  173.469.
    (41) ISO 10156:2017(E), Gas cylinders--Gases and gas mixtures--
Determination of fire potential and oxidizing ability for the selection 
of cylinder valve outlets, Fourth edition, 2017-07; into Sec.  173.115.
    (42) ISO 10297:1999(E), Gas cylinders--Refillable gas cylinder 
valves--Specification and type testing, First Edition, 1995-05-01; into 
Sec. Sec.  173.301b; 178.71.
    (43) ISO 10297:2006(E), Transportable gas cylinders--Cylinder 
valves--Specification and type testing, Second Edition, 2006-01-15; 
into Sec. Sec.  173.301b; 178.71.
    (44) ISO 10297:2014(E), Gas cylinders--Cylinder valves--
Specification and type testing, Third Edition, 2014-07-15; into 
Sec. Sec.  173.301b; 178.71.
    (45) ISO 10297:2014/Amd 1:2017(E), Gas cylinders--Cylinder valves--
Specification and type testing--Amendment 1: Pressure drums and tubes, 
Third Edition, 2017-03; into Sec. Sec.  173.301b; 178.71.
    (46) ISO 10461:2005(E), Gas cylinders--Seamless aluminum-alloy gas 
cylinders--Periodic inspection and testing, Second Edition, 2005-02-15 
and Amendment 1, 2006-07-15; into Sec.  180.207.
    (47) ISO 10462:2013(E), Gas cylinders--Acetylene cylinders--
Periodic inspection and maintenance, Third Edition, 2013-12-15; into 
Sec.  180.207.
    (48) ISO 10462:2013/Amd 1:2019(E), ``Gas cylinders--Acetylene 
cylinders--Periodic inspection and maintenance--Amendment 1, Third 
Edition, 2019-06; into Sec.  180.207.
    (49) ISO 10692-2:2001(E), Gas cylinders--Gas cylinder valve 
connections for use in the micro-electronics industry--Part 2: 
Specification and type testing for valve to cylinder connections, First 
Edition, 2001-08-01; into Sec. Sec.  173.40; 173.302c.
    (50) ISO 11114-1:2012(E), Gas cylinders--Compatibility of cylinder 
and valve materials with gas contents--Part 1: Metallic materials, 
Second edition, 2012-03-15; into Sec. Sec.  172.102; 173.301b; 178.71.
    (51) ISO 11114-1:2012/Amd 1:2017(E), Gas cylinders--Compatibility 
of cylinder and valve materials with gas contents--Part 1: Metallic 
materials--Amendment 1, Second Edition, 2017-01; into Sec. Sec.  
172.102, 173.301b, 178.71.
    (52) ISO 11114-2:2013(E), Gas cylinders--Compatibility of cylinder 
and valve materials with gas contents--Part 2: Non-metallic materials, 
Second edition, 2013-04; into Sec. Sec.  173.301b; 178.71.
    (53) ISO 11117:1998(E): Gas cylinders--Valve protection caps and 
valve guards for industrial and medical gas cylinders--Design, 
construction and tests, First edition, 1998-08-01; into Sec.  173.301b.
    (54) ISO 11117:2008(E): Gas cylinders--Valve protection caps and 
valve guards--Design, construction and tests, Second edition, 2008-09-
01; into Sec.  173.301b.
    (55) ISO 11117:2008/Cor.1:2009(E): Gas cylinders--Valve protection 
caps and valve guards--Design, construction and tests, Technical 
Corrigendum 1, 2009-05-01; into Sec.  173.301b.
    (56) ISO 11117:2019(E), ``Gas cylinders--Valve protection caps and 
guards--Design, construction and tests, 2019-11-01; into Sec.  
173.301b.
    (57) ISO 11118(E), Gas cylinders--Non-refillable metallic gas 
cylinders--Specification and test methods, First edition, October 1999; 
into Sec.  178.71.
    (58) ISO 11118:2015(E), Gas cylinders--Non-refillable metallic gas 
cylinders--Specification and test methods, Second edition, 2015-09-15; 
into Sec. Sec.  173.301b; 178.71.
    (59) ISO 11118:2015/Amd 1:2019(E), Gas cylinders--Non-refillable 
metallic gas cylinders--Specification and test methods--Amendment 1, 
Second edition, 2019-10; into Sec. Sec.  173.301b; 178.71.
    (60) ISO 11119-1(E), Gas cylinders--Gas cylinders of composite 
construction--Specification and test methods--Part 1: Hoop-wrapped 
composite gas cylinders, First edition, May 2002, into Sec.  178.71.
    (61) ISO 11119-1:2012(E), Gas cylinders--Refillable composite gas 
cylinders and tubes--Design, construction and testing--Part 1: Hoop 
wrapped fibre reinforced composite gas cylinders and tubes up to 450 L, 
Second edition, 2012-08-01; into Sec. Sec.  178.71; 178.75.
    (62) ISO 11119-2(E), Gas cylinders--Gas cylinders of composite 
construction--Specification and test methods--Part 2: Fully wrapped 
fibre reinforced composite gas cylinders with load-sharing metal 
liners, First edition, May 2002; into Sec.  178.71.
    (63) ISO 11119-2:2012(E), Gas cylinders--Refillable composite gas 
cylinders and tubes--Design, construction and testing--Part 2: Fully 
wrapped fibre reinforced composite gas cylinders and tubes up to 450 l 
with load-sharing metal liners, Second edition, 2012-07-15; into 
Sec. Sec.  178.71; 178.75.
    (64) ISO 11119-2:2012/Amd.1:2014(E), Gas cylinders--

[[Page 34601]]

Refillable composite gas cylinders and tubes--Design, construction and 
testing--Part 2: Fully wrapped fibre reinforced composite gas cylinders 
and tubes up to 450 l with load-sharing metal liners, Amendment 1, 
2014-08-15; into Sec. Sec.  178.71; 178.75.
    (65) ISO 11119-3(E), Gas cylinders of composite construction--
Specification and test methods--Part 3: Fully wrapped fibre reinforced 
composite gas cylinders with non-load-sharing metallic or non-metallic 
liners, First edition, September 2002; into Sec.  178.71.
    (66) ISO 11119-3:2013(E), Gas cylinders--Refillable composite gas 
cylinders and tubes--Design, construction and testing--Part 3: Fully 
wrapped fibre reinforced composite gas cylinders and tubes up to 450 l 
with non-load-sharing metallic or non-metallic liners, Second edition, 
2013-04-15; into Sec. Sec.  178.71; 178.75.
    (67) ISO 11119-4:2016(E), Gas cylinders--Refillable composite gas 
cylinders--Design, construction and testing--Part 4: Fully wrapped 
fibre reinforced composite gas cylinders up to 150 l with load-sharing 
welded metallic liners, First Edition, 2016-02-15; into Sec.  178.71; 
178.75.
    (68) ISO 11120(E), Gas cylinders--Refillable seamless steel tubes 
of water capacity between 150 l and 3000 l--Design, construction and 
testing, First edition, 1999-03; into Sec. Sec.  178.71; 178.75.
    (69) ISO 11120:2015(E), Gas cylinders--Refillable seamless steel 
tubes of water capacity between 150 l and 3000 l--Design, construction 
and testing, Second Edition, 2015-02-01; into Sec. Sec.  178.71; 
178.75.
    (70) ISO 11513:2011(E), Gas cylinders--Refillable welded steel 
cylinders containing materials for sub-atmospheric gas packaging 
(excluding acetylene)--Design, construction, testing, use and periodic 
inspection, First edition, 2011-09-12; into Sec. Sec.  173.302c; 
178.71; 180.207.
    (71) ISO 11513:2019(E), Gas cylinders--Refillable welded steel 
cylinders containing materials for sub-atmospheric gas packaging 
(excluding acetylene)--Design, construction, testing, use and periodic 
inspection, Second edition, 2019-09; into Sec. Sec.  173.302c; 178.71; 
180.207.
    (72) ISO 11621(E), Gas cylinders--Procedures for change of gas 
service, First edition, April 1997; into Sec. Sec.  173.302, 173.336, 
173.337.
    (73) ISO 11623(E), Transportable gas cylinders--Periodic inspection 
and testing of composite gas cylinders, First edition, March 2002; into 
Sec.  180.207.
    (74) ISO 11623:2015 (E), Gas cylinders--Composite construction--
Periodic inspection and testing, Second edition, 2015-12-01; into Sec.  
180.207.
    (75) ISO 13340:2001(E), Transportable gas cylinders--Cylinder 
valves for non-refillable cylinders--Specification and prototype 
testing, First edition, 2004-04-01; into Sec.  178.71.
    (76) ISO 13736:2008(E), Determination of flash point--Abel closed-
cup method, Second Edition, 2008-09-15; into Sec.  173.120.
    (77) ISO 14246:2014(E), Gas cylinders--Cylinder valves--
Manufacturing tests and examination, Second Edition, 2014-06-15; into 
Sec.  178.71.
    (78) ISO 14246:2014/Amd 1:2017(E), Gas cylinders--Cylinder valves--
Manufacturing tests and examinations--Amendment 1, Second Edition, 
2017-06; into Sec.  178.71.
    (79) ISO 16111:2008(E), Transportable gas storage devices--Hydrogen 
absorbed in reversible metal hydride, First Edition, 2008-11-15; into 
Sec. Sec.  173.301b; 173.311; 178.71.
    (80) ISO 16111:2018(E), Transportable gas storage devices--Hydrogen 
absorbed in reversible metal hydride, Second Edition, 2018-08; into 
Sec. Sec.  173.301b; 173.311; 178.71.
    (81) ISO 16148:2016(E), Gas cylinders--Refillable seamless steel 
gas cylinders and tubes--Acoustic emission examination (AT) and follow-
up ultrasonic examination (UT) for periodic inspection and testing, 
Second Edition, 2016-04-15; into Sec.  180.207.
    (82) ISO 17871:2015(E), Gas cylinders--Quick-release cylinder 
valves--Specification and type testing, First Edition, 2015-08-15; into 
Sec.  173.301b.
    (83) ISO 17871:2020(E), Gas cylinders--Quick-release cylinder 
valves--Specification and type testing, Second Edition, 2020-07; into 
Sec.  173.301b.
    (84) ISO 17879: 2017(E), Gas cylinders--Self-closing cylinder 
valves--Specification and type testing, First Edition, 2017-07; into 
Sec. Sec.  173.301b; 178.71.
    (85) ISO 18172-1:2007(E), Gas cylinders--Refillable welded 
stainless steel cylinders--Part 1: Test pressure 6 MPa and below, First 
Edition, 2007-03-01; into Sec.  178.71.
    (86) ISO 20475:2018(E), Gas cylinders--Cylinder bundles--Periodic 
inspection and testing, First Edition, 2018-02; into Sec.  180.207.
    (87) ISO 20703:2006(E), Gas cylinders--Refillable welded aluminum-
alloy cylinders--Design, construction and testing, First Edition, 2006-
05-01; into Sec.  178.71.
    (88) ISO 21172-1:2015(E), Gas cylinders--Welded steel pressure 
drums up to 3,000 litres capacity for the transport of gases--Design 
and construction--Part 1: Capacities up to 1,000 litres, First edition, 
2015-04-01; into Sec.  178.71.
    (89) ISO 21172-1:2015/Amd 1:2018(E), Gas cylinders--Welded steel 
pressure drums up to 3,000 litres capacity for the transport of gases--
Design and construction--Part 1: Capacities up to 1,000 litres--
Amendment 1, First Edition, 2018-11-01; into Sec.  178.71.
    (90) ISO 22434:2006(E), Transportable gas cylinders--Inspection and 
maintenance of cylinder valves, First Edition, 2006-09-01; into Sec.  
180.207.
    (91) ISO 23088:2020, Gas cylinders--Periodic inspection and testing 
of welded steel pressure drums--Capacities up to 1,000 l, First 
Edition, 2020-02; into Sec.  180.207.
    (92) ISO/TR 11364:2012(E), Gas cylinders--Compilation of national 
and international valve stem/gas cylinder neck threads and their 
identification and marking system, First Edition, 2012-12-01; into 
Sec.  178.71.
* * * * *
    (aa) * * *
    (3) Test No. 439: In Vitro Skin Irritation: Reconstructed Human 
Epidermis (RHE) Test Method, OECD Guidelines for the Testing of 
Chemicals, 29 July 2015; into Sec.  173.137.
* * * * *
    (dd) * * *
    (1) UN Recommendations on the Transport of Dangerous Goods, Model 
Regulations (UN Recommendations), 22nd revised edition, (2021); into 
Sec. Sec.  171.8; 171.12; 172.202; 172.401; 172.407; 172.502; 172.519; 
173.22; 173.24; 173.24b; 173.40; 173.56; 173.192; 173.302b; 173.304b; 
178.75; 178.274 as follows:
    (i) Volume I, ST/SG/AC.10/1/Rev.22 (Vol. I).
    (ii) Volume II, ST/SG/AC.10/1/Rev.22 (Vol. II).
    (2) Manual of Tests and Criteria; into Sec. Sec.  171.24, 172.102; 
173.21; 173.56; 173.57; 173.58; 173.60; 173.115; 173.124; 173.125; 
173.127; 173.128; 173.137; 173.185; 173.220; 173.221; 173.224; 173.225; 
173.232; part 173, appendix H; 175.10; 176.905; 178.274 as follows:
    (i) Seventh revised edition (2019).
    (ii) Seventh revised edition, Amendment 1 (2021).
    (3) Globally Harmonized System of Classification and Labelling of 
Chemicals (GHS), 9th revised edition, ST/SG/AC.10/30/Rev.9 (2021); into 
Sec.  172.401.
    (4) Agreement concerning the International Carriage of Dangerous

[[Page 34602]]

Goods by Road (ADR), copyright 2020; into Sec.  171.23 as follows:
    (i) Volume I, ECE/TRANS/300 (Vol. I).
    (ii) Volume II, ECE/TRANS/300 (Vol. II).
    (iii) Corrigendum, ECE/TRANS/300 (Corr. 1).
* * * * *
0
3. In Sec.  171.12, revise paragraph (a)(4)(iii) to read as follows:

Sec.  171.12  North American Shipments.

* * * * *
    (a) * * *
    (4) * * *
    (iii) Authorized CRC, BTC, CTC or TC specification cylinders that 
correspond with a DOT specification cylinder are as follows:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                   DOT (some or all of these specifications may instead be      CTC (some or all of these specifications may instead be
               TC                                marked with the prefix ICC)                              marked with the prefix BTC or CRC)
--------------------------------------------------------------------------------------------------------------------------------------------------------
TC-3AM.........................  DOT-3A [ICC-3].............................................  CTC-3A.
TC-3AAM........................  DOT-3AA....................................................  CTC-3AA
TC-3ANM........................  DOT-3BN....................................................  CTC-3BN.
TC-3EM.........................  DOT-3E.....................................................  CTC-3E.
TC-3HTM........................  DOT-3HT....................................................  CTC-3HT.
TC-3ALM........................  DOT-3AL....................................................  CTC-3AL.
                                 DOT-3B.....................................................  CTC-3B.
TC-3AXM........................  DOT-3AX....................................................  CTC-3AX.
TC-3AAXM.......................  DOT-3AAX...................................................  CTC-3AAX.
                                 DOT-3A480X.................................................  CTC-3A480X.
TC-3TM.........................  DOT-3T.....................................................  ..........................................................
TC-4AAM33......................  DOT-4AA480.................................................  CTC-4AA480.
TC-4BM.........................  DOT-4B.....................................................  CTC-4B.
TC-4BM17ET.....................  DOT-4B240ET................................................  CTC-4B240ET.
TC-4BAM........................  DOT-4BA....................................................  CTC-4BA.
TC-4BWM........................  DOT-4BW....................................................  CTC-4BW.
TC-4DM.........................  DOT-4D.....................................................  CTC-4D.
TC-4DAM........................  DOT-4DA....................................................  CTC-4DA.
TC-4DSM........................  DOT-4DS....................................................  CTC-4DS.
TC-4EM.........................  DOT-4E.....................................................  CTC-4E.
TC-39M.........................  DOT-39.....................................................  CTC-39.
TC-4LM.........................  DOT-4L.....................................................  CTC-4L.
TC-8WM.........................  DOT-8......................................................  CTC-8.
TC8-WAM........................  DOT-8AL....................................................  CTC-8AL.
--------------------------------------------------------------------------------------------------------------------------------------------------------

* * * * *
0
4. In Sec.  171.23, revise paragraph (a)(3) to read as follows:

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

    (a) * * *
    (3) Pi-marked cylinders. Cylinders with a water capacity not 
exceeding 150 L and that are marked with a pi mark, in accordance with 
the European Directive 2010/35/EU (IBR, see Sec.  171.7), on 
transportable pressure equipment (TPED), and that comply with the 
requirements of Packing Instruction P200 or P208 and 6.2 of the 
Agreement Concerning the International Carriage of Dangerous Goods by 
Road (ADR) (IBR, see Sec.  171.7), concerning pressure relief device 
use, test period, filling ratios, test pressure, maximum working 
pressure, and material compatibility for the lading contained or gas 
being filled, are authorized as follows:
    (i) Filled cylinders imported for intermediate storage, transport 
to point of use, discharge, and export without further filling; and
    (ii) Cylinders imported or domestically sourced for the purpose of 
filling, intermediate storage, and export.
    (iii) The bill of lading or other shipping paper must identify the 
cylinder and include the following certification: ``This cylinder 
(These cylinders) conform(s) to the requirements for pi-marked 
cylinders found in Sec.  171.23(a)(3).''
* * * * *
0
5. In Sec.  171.25:
0
a. Revise paragraphs (c)(3) and (4); and
0
b. Add paragraph (c)(5).
    To read as follows:

Sec.  171.25  Conditions and requirements for bulk packagings.

* * * * *
    (c) * * *
    (3) Except as specified in this subpart, for a material poisonous 
(toxic) by inhalation, the T Codes specified in Column 13 of the 
Dangerous Goods List in the IMDG Code may be applied to the 
transportation of those materials in IM, IMO, and DOT Specification 51 
portable tanks, when these portable tanks are authorized in accordance 
with the requirements of this subchapter;
    (4) No person may offer an IM or UN portable tank containing liquid 
hazardous materials of Class 3, PG I or II, or PG III with a flash 
point less than 100 [deg]F (38 [deg]C); Division 5.1, PG I or II; or 
Division 6.1, PG I or II, for unloading while it remains on a transport 
vehicle with the motive power unit attached, unless it conforms to the 
requirements in Sec.  177.834(o) of this subchapter; and
    (5) No person may offer a UN fiber-reinforced plastic portable tank 
meeting the provisions of Chapter 6.10 of the IMDG Code (IBR, see Sec.  
171.7), except for transportation falling within the single port area 
criteria in paragraph (d) of this section.
* * * * *

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

0
6. The authority citation for part 172 continues to read as follows:

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

[[Page 34603]]

0
7. In 172.101:
0
a. Revise paragraph (c)(12)(ii); and
0
b. In the Hazardous Materials Table, amend by removing the entries 
under ``[REMOVE]'' by adding the entries under ``[ADD]'' and by 
revising entries under ``[REVISE]'' in the appropriate alphabetical 
sequence.
    The additions and revisions read as follows:

Sec.  172.101  Purpose and use of the hazardous materials table.

    (c) * * *
    (12) * * *
    (ii) Generic or n.o.s. descriptions. If an appropriate technical 
name is not shown in the Table, selection of a proper shipping name 
shall be made from the generic or n.o.s. descriptions corresponding to 
the specific hazard class, packing group, hazard zone, or subsidiary 
hazard, if any, for the material. The name that most appropriately 
describes the material shall be used, e.g., an alcohol not listed by 
its technical name in the Table shall be described as ``Alcohol, 
n.o.s.'' rather than ``Flammable liquid, n.o.s.'' Some mixtures may be 
more appropriately described according to their application, such as 
``Coating solution'' or ``Extracts, liquid, for flavor or aroma,'' 
rather than by an n.o.s. entry, such as ``Flammable liquid, n.o.s.'' It 
should be noted, however, that an n.o.s. description as a proper 
shipping name may not provide sufficient information for shipping 
papers and package markings. Under the provisions of subparts C and D 
of this part, the technical name of one or more constituents which 
makes the product a hazardous material may be required in association 
with the proper shipping name.
* * * * *
BILLING CODE 4910-60-P

[[Page 34604]]

[GRAPHIC] [TIFF OMITTED] TP30MY23.000

[[Page 34605]]

[GRAPHIC] [TIFF OMITTED] TP30MY23.001

[[Page 34606]]

[GRAPHIC] [TIFF OMITTED] TP30MY23.002

BILLING CODE 4910-60-C
* * * * *
0
8. In Sec.  172.102 paragraph (c)(1):
0
a. Revise special provisions 78, 156, 387;
0
b. Add special provisions 396, 398;
0
c. Remove and reserve special provision 421;
0
d. Add special provision 441;
0
e. Revise special provision A54 and;

[[Page 34607]]

0
 f. Add special provisions A224, A225, IP15, IP22 in numerical order.
    The additions and revisions read as follows:

Sec.  172.102  Special provisions.

* * * * *
    (c) * * *
    (1) * * *
    78 Mixtures of nitrogen and oxygen containing not less than 19.5% 
and not more than 23.5% oxygen by volume may be transported under this 
entry when no other oxidizing gases are present. A Division 5.1 
subsidiary hazard label is not required for any concentrations within 
this limit. Compressed air containing greater than 23.5% oxygen by 
volume must be shipped using the description ``Compressed gas, 
oxidizing, n.o.s., UN3156.''
* * * * *
    156 Asbestos that is immersed or fixed in a natural or artificial 
binder material, such as cement, plastic, asphalt, resins, or mineral 
ore, or contained in manufactured products, is not subject to the 
requirements of this subchapter, except that when transported by air, 
an indication of compliance with this special provision must be 
provided by including the words ``not restricted'' on a shipping paper, 
such as an air waybill accompanying the shipment.
* * * * *
    387 When materials are stabilized by temperature control, the 
provisions of Sec.  173.21(f) of this subchapter apply. When chemical 
stabilization is employed, the person offering the material for 
transport shall ensure that the level of stabilization is sufficient to 
prevent the material as packaged from dangerous polymerization at 50 
[deg]C (122 [deg]F). If chemical stabilization becomes ineffective at 
lower temperatures within the anticipated duration of transport, 
temperature control is required and is forbidden by aircraft. In making 
this determination factors to be taken into consideration include, but 
are not limited to, the capacity and geometry of the packaging and the 
effect of any insulation present; the temperature of the material when 
offered for transport; the duration of the journey and the ambient 
temperature conditions typically encountered in the journey 
(considering also the season of year); the effectiveness and other 
properties of the stabilizer employed; applicable operational controls 
imposed by regulation (e.g., requirements to protect from sources of 
heat, including other cargo carried at a temperature above ambient); 
and any other relevant factors.
* * * * *
    396 Large and robust articles may be transported with connected gas 
cylinders with the valves open regardless of Sec.  173.24(b)(1), 
provided:
    a. the gas cylinders contain nitrogen of UN 1066 or compressed gas 
of UN 1956 or compressed air of UN1002;
    b. the gas cylinders are connected to the article through pressure 
regulators and fixed piping in such a way that the pressure of the gas 
(gauge pressure) in the article does not exceed 35 kPa (0.35 bar);
    c. the gas cylinders are properly secured so that they cannot shift 
in relation to the article and are fitted with strong and pressure 
resistant hoses and pipes;
    d. the gas cylinders, pressure regulators, piping, and other 
components are protected from damage and impacts during transport by 
wooden crates or other suitable means;
    e. the shipping paper must include the following statement: 
``Transport in accordance with special provision 396.''; and
    f. cargo transport units containing articles transported with 
cylinders with open valves containing a gas presenting a risk of 
asphyxiation are well ventilated.
* * * * *
    398 This entry applies to 1-butylene, cis-2-butylene and trans-2-
butylene, and mixtures of butylenes. For isobutylene, see UN 1055.
* * * * *
    421 [Reserved]
    441 Mixtures of fluorine and nitrogen with a fluorine concentration 
below 35% by volume may be filled in pressure receptacles up to a 
maximum allowable working pressure for which the partial pressure of 
fluorine does not exceed 31 bar (abs.).

Working pressure
(bar)<31/xf-1, in which xf = fluorine concentration in % by volume/100.

    Mixtures of fluorine and inert gases with a fluorine concentration 
below 35% by volume may be filled in pressure receptacles up to a 
maximum allowable working pressure for which the partial pressure of 
fluorine does not exceed 31 bar (abs.), additionally taking the 
coefficient of nitrogen equivalency in accordance with ISO 10156:2017 
into account when calculating the partial pressure.

Working pressure (bar)<31xf(xf+Kkxxk)-1, in which xf = fluorine 
concentration in % by volume/100; Kk = coefficient of equivalency of an 
inert gas relative to nitrogen (coefficient of nitrogen equivalency); 
xk = inert gas concentration in % by volume/100;
Kk = coefficient of equivalency of an inert gas relative to nitrogen 
(coefficient of nitrogen equivalency);
xk = inert gas concentration in % by volume/100.

    However, the working pressure for mixtures of fluorine and inert 
gases shall not exceed 200 bar. The minimum test pressure of pressure 
receptacles for mixtures of fluorine and inert gases equals 1.5 times 
the working pressure or 200 bar, with the greater value to be applied.
* * * * *
    A54 Irrespective of the quantity limits in Column 9B of the Sec.  
172.101 table, a lithium battery, including a lithium battery packed 
with, or contained in, equipment that otherwise meets the applicable 
requirements of Sec.  173.185, may have a mass exceeding 35 kg if 
approved by the Associate Administrator prior to shipment in accordance 
with this special provision must be noted on the shipping papers.
* * * * *
    A224 UN3548, Articles containing miscellaneous dangerous goods, 
n.o.s. may be transported on passenger and cargo aircraft, irrespective 
of the indication of ``forbidden'' in Columns (9A) and (9B) of the 
Hazardous Materials Table, provided: (a) the only dangerous good 
contained in the article is an environmentally hazardous substance, or 
lithium cells or batteries that comply with Sec.  173.185; (b) the 
articles are packed in accordance with Sec.  173.232; and (c) reference 
to Special Provision A224 is made on the shipping paper.
* * * * *
    A225 UN3538, Articles containing non-flammable, non-toxic gas, 
n.o.s. may be transported on passenger and cargo aircraft irrespective 
of the indication of ``forbidden'' in Columns (9A) and (9B) of the 
Hazardous Materials Table, provided: (a) the only dangerous good 
contained in the article is a Division 2.2 gas without a subsidiary 
hazard, but excluding refrigerated liquefied gases and gases forbidden 
for transport on passenger aircraft, or lithium cells or batteries that 
comply with Sec.  173.185; (b) the articles are packed in accordance 
with Sec.  173.232 and limited to a maximum net quantity of gas of 75 
kg by passenger aircraft and 150 kg by cargo aircraft; and (c) 
reference to Special Provision A225 is made on the shipping paper.
* * * * *

[[Page 34608]]

    IP15 For UN2031 with more than 55% nitric acid, the permitted use 
of rigid plastic IBCs, and the inner receptacle of composite IBCs with 
rigid plastics, shall be two years from their date of manufacture.
* * * * *
    IP22 UN3550 may be transported in flexible IBCs (13H3 or 13H4) with 
siftproof liners to prevent any egress of dust during transport.
* * * * *

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

0
9. The authority citation for part 173 continues to read as follows:

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

0
10. In Sec.  173.4b, revise paragraph (b)(1) to read as follows:

Sec.  173.4b  De minimis exceptions.

* * * * *
    (b) * * *
    (1) The specimens are:
    (i) Wrapped in a paper towel or cheesecloth moistened with alcohol, 
an alcohol solution, or a formaldehyde solution and placed in a plastic 
bag that is heat-sealed. Any free liquid in the bag must not exceed 30 
mL; or
    (ii) Placed in vials or other rigid containers with no more than 30 
mL of alcohol, an alcohol solution, or a formaldehyde solution. The 
containers are placed in a plastic bag that is heat-sealed;
* * * * *
0
11. In Sec.  173.21 revise paragraphs (f) introductory text, (f)(1), 
and (f)(2) to read as follows:

Sec.  173.21  Forbidden materials and packages.

* * * * *
    (f) A package containing a material which is likely to decompose 
with a self-accelerated decomposition temperature (SADT) or polymerize 
with a self-accelerated polymerization temperature (SAPT) of 50 [deg]C 
(122 [deg]F) or less, or 45 [deg]C (113 [deg]F) or less when offered 
for transportation in portable tanks, with an evolution of a dangerous 
quantity of heat or gas when decomposing or polymerizing, unless the 
material is stabilized or inhibited in a manner to preclude such 
evolution. For organic peroxides see paragraph (f)(2) of this section. 
The SADT and SAPT may be determined by any of the test methods 
described in Part II of the UN Manual of Tests and Criteria (IBR, see 
Sec.  171.7 of this subchapter).
    (1) A package meeting the criteria of paragraph (f) of this section 
may be required to be shipped under controlled temperature conditions. 
The control temperature and emergency temperature for a package shall 
be as specified in Table 1 in this paragraph based upon the SADT or 
SAPT of the material. The control temperature is the temperature above 
which a package of the material may not be offered for transportation 
or transported. The emergency temperature is the temperature at which, 
due to imminent danger, emergency measures must be initiated.

                  Table 1 to Paragraph (f)(1)--Derivation of Control and Emergency Temperature
----------------------------------------------------------------------------------------------------------------
          Type of receptacle                SADT/SAPT \1\         Control temperatures    Emergency temperature
----------------------------------------------------------------------------------------------------------------
Single packagings and IBCs...........  SADT/SAPT <=20 [deg]C    20 [deg]C (36 [deg]F)    10 [deg]C (18 [deg]F)
                                        (68 [deg]F).             below SADT/SAPT.         below SADT/SAPT.
Single packagings and IBCs...........  20 [deg]C (68 [deg]F)    15 [deg]C (27 [deg]F)    10 [deg]C (18 [deg]F)
                                        =88 + <=12               OP8                 -10                  0  .........
 Diisopropylperoxydicarbonate.....................
2,5-Dimethoxy-4-(4-                                           3236                79               OP7                + 40               + 45  .........
 methylphenylsulphony)benzenediazonium zinc
 chloride.........................................
4-Dimethylamino-6-(2-dimethylaminoethoxy)toluene-2-           3236               100               OP7                + 40               + 45  .........
 diazonium zinc chloride..........................
4-(Dimethylamino)-benzenediazonium                            3228               100               OP8  .....................  ..............  .........
 trichlorozincate (-1)............................
N,N'-Dinitroso-N, N'-dimethyl-terephthalamide, as             3224                72               OP6  .....................  ..............  .........
 a paste..........................................
N,N'-Dinitrosopentamethylenetetramine.............            3224                82               OP6  .....................  ..............          2
Diphenyloxide-4,4'-disulphohydrazide..............            3226               100               OP7  .....................  ..............  .........
Diphenyloxide-4,4'-disulphonylhydrazide...........            3226               100               OP7  .....................  ..............  .........
4-Dipropylaminobenzenediazonium zinc chloride.....            3226               100               OP7  .....................  ..............  .........
2-(N,N-Ethoxycarbonylphenylamino)-3-methoxy-4-(N-             3236             63-92               OP7                + 40               + 45  .........
 methyl-N- cyclohexylamino)benzenediazonium zinc
 chloride.........................................
2-(N,N-Ethoxycarbonylphenylamino)-3-methoxy-4-(N-             3236                62               OP7                + 35               + 40  .........
 methyl-N- cyclohexylamino)benzenediazonium zinc
 chloride.........................................
N-Formyl-2-(nitromethylene)-1,3-perhydrothiazine..            3236               100               OP7                + 45               + 50  .........
2-(2-Hydroxyethoxy)-1-(pyrrolidin-1-yl)benzene-4-             3236               100               OP7                + 45               + 50  .........
 diazonium zinc chloride..........................
3-(2-Hydroxyethoxy)-4-(pyrrolidin-1-                          3236               100               OP7                + 40               + 45  .........
 yl)benzenediazonium zinc chloride................

[[Page 34613]]

 
7-Methoxy-5-methyl-benzothiophen-2-yl boronic                 3230            88-100    ..............  .....................  ..............          6
 acid''...........................................
2-(N,N-Methylaminoethylcarbonyl)-4-(3,4-dimethyl-             3236                96               OP7                + 45               + 50  .........
 phenylsulphonyl) benzenediazonium hydrogen
 sulphate.........................................
4-Methylbenzenesulphonylhydrazide.................            3226               100               OP7  .....................  ..............  .........
3-Methyl-4-(pyrrolidin-1-yl)benzenediazonium                  3234                95               OP6                + 45               + 50  .........
 tetrafluoroborate................................
4-Nitrosophenol...................................            3236               100               OP7                + 35               + 40  .........
Phosphorothioic acid, O-[(cyanophenyl methylene)              3227             82-91               OP8  .....................  ..............          5
 azanyl] O,O-diethyl ester........................                        (Z isomer)
Self-reactive liquid, sample......................            3223  ..................             OP2  .....................  ..............          3
Self-reactive liquid, sample, temperature control.            3233  ..................             OP2  .....................  ..............          3
Self-reactive solid, sample.......................            3224  ..................             OP2  .....................  ..............          3
Self-reactive solid, sample, temperature control..            3234  ..................             OP2  .....................  ..............          3
Sodium 2-diazo-1-naphthol-4-sulphonate............            3226               100               OP7  .....................  ..............  .........
Sodium 2-diazo-1-naphthol-5-sulphonate............            3226               100               OP7  .....................  ..............  .........
Tetramine palladium (II) nitrate..................            3234               100               OP6                + 30               + 35  .........
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes: 1. The emergency and control temperatures must be determined in accordance with Sec.   173.21(f).
2. With a compatible diluent having a boiling point of not less than 150 [deg]C.
3. Samples may only be offered for transportation under the provisions of paragraph (c)(3) of this section.
4. This entry applies to mixtures of esters of 2-diazo-1-naphthol-4-sulphonic acid and 2-diazo-1-naphthol-5-sulphonic acid.

    5. This entry applies to the technical mixture in n-butanol within 
the specified concentration limits of the (Z) isomer.
    6. The technical compound with the specified concentration limits 
may contain up to 12% water and up to 1% organic impurities.
* * * * *
0
18. In Sec.  173.225:
0
a. Revise table 1 to paragraph (c);
0
b. Designate the tables immediately following paragraph (d) and 
immediately following paragraph (g) as table 2 to paragraph (d) and 
table 4 to paragraph (g), respectively; and
0
c. Revise newly-designated table 4 to paragraph (g).

Sec.  173.225  Packaging requirements and other provisions for organic 
peroxides.

* * * * *
    (c) * * *

                                                    Table 1 to Paragraph (c): Organic Peroxide Table
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Diluent (mass %)                                   Temperature ([deg]C)
         Technical name              ID No.      Concentration  ------------------------------   Water       Packing    -----------------------   Notes
                                                    (mass %)         A         B         I      (mass %)      method      Control   Emergency
(1)                              (2)                        (3)      (4a)      (4b)      (4c)        (5)  (6)                (7a)         (7b)       (8)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acetyl acetone peroxide........  UN3105                    <=42      >=48  ........  ........        >=8  OP7            ........  ...........         2
Acetyl acetone peroxide........  UN3107                    <=35  ........  ........  ........        >=8  OP8            ........  ...........        32
Acetyl acetone peroxide [as a    UN3106                    <=32  ........  ........  ........  .........  OP7            ........  ...........        21
 paste].
Acetyl cyclohexanesulfonyl       UN3112                    <=82  ........  ........  ........       >=12  OP4                 -10            0  ........
 peroxide.
Acetyl cyclohexanesulfonyl       UN3115                    <=32  ........      >=68  ........  .........  OP7                 -10            0  ........
 peroxide.
tert-Amyl hydroperoxide........  UN3107                    <=88       >=6  ........  ........        >=6  OP8            ........  ...........  ........
tert-Amyl peroxyacetate........  UN3105                    <=62      >=38  ........  ........  .........  OP7            ........  ...........  ........
tert-Amyl peroxybenzoate.......  UN3103                   <=100  ........  ........  ........  .........  OP5            ........  ...........  ........
tert-Amyl peroxy-2-              UN3115                   <=100  ........  ........  ........  .........  OP7                  20           25  ........
 ethylhexanoate.
tert-Amyl peroxy-2-ethylhexyl    UN3105                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 carbonate.
tert-Amyl peroxy isopropyl       UN3103                    <=77      >=23  ........  ........  .........  OP5            ........  ...........  ........
 carbonate.
tert-Amyl peroxyneodecanoate...  UN3115                    <=77  ........      >=23  ........  .........  OP7                   0           10  ........
tert-Amyl peroxyneodecanoate...  UN3119                    <=47      >=53  ........  ........  .........  OP8                   0           10  ........
tert-Amyl peroxypivalate.......  UN3113                    <=77  ........      >=23  ........  .........  OP5                  10           15  ........
tert-Amyl peroxypivalate.......  UN3119                    <=32      >=68  ........  ........  .........  OP8                  10           15  ........
tert-Amyl peroxy-3,5,5-          UN3105                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 trimethylhexanoate.
tert-Butyl cumyl peroxide......  UN3109                 >42-100  ........  ........  ........  .........  OP8            ........  ...........         9
tert-Butyl cumyl peroxide......  UN3108                    <=52  ........  ........      >=48  .........  OP8            ........  ...........         9
n-Butyl-4,4-di-(tert-            UN3103                 >52-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)valerate.
n-Butyl-4,4-di-(tert-            UN3108                    <=52  ........  ........      >=48  .........  OP8            ........  ...........  ........
 butylperoxy)valerate.
tert-Butyl hydroperoxide.......  UN3103                  >79-90  ........  ........  ........       >=10  OP5            ........  ...........        13
tert-Butyl hydroperoxide.......  UN3105                    <=80      >=20  ........  ........  .........  OP7            ........  ...........     4, 13
tert-Butyl hydroperoxide.......  UN3107                    <=79  ........  ........  ........        >14  OP8            ........  ...........    13, 16
tert-Butyl hydroperoxide.......  UN3109                    <=72  ........  ........  ........       >=28  OP8            ........  ...........        13

[[Page 34614]]

 
tert-Butyl hydroperoxide [and]   UN3103                <82 + >9  ........  ........  ........        >=7  OP5            ........  ...........        13
 Di-tert-butylperoxide.
tert-Butyl monoperoxymaleate...  UN3102                 >52-100  ........  ........  ........  .........  OP5            ........  ...........  ........
tert-Butyl monoperoxymaleate...  UN3103                    <=52      >=48  ........  ........  .........  OP6            ........  ...........  ........
tert-Butyl monoperoxymaleate...  UN3108                    <=52  ........  ........      >=48  .........  OP8            ........  ...........  ........
tert-Butyl monoperoxymaleate     UN3108                    <=52  ........  ........  ........  .........  OP8            ........  ...........  ........
 [as a paste].
tert-Butyl peroxyacetate.......  UN3101                  >52-77      >=23  ........  ........  .........  OP5            ........  ...........  ........
tert-Butyl peroxyacetate.......  UN3103                  >32-52      >=48  ........  ........  .........  OP6            ........  ...........  ........
tert-Butyl peroxyacetate.......  UN3109                    <=32  ........      >=68  ........  .........  OP8            ........  ...........  ........
tert-Butyl peroxybenzoate......  UN3103                 >77-100  ........  ........  ........  .........  OP5            ........  ...........  ........
tert-Butyl peroxybenzoate......  UN3105                  >52-77      >=23  ........  ........  .........  OP7            ........  ...........         1
tert-Butyl peroxybenzoate......  UN3106                    <=52  ........  ........      >=48  .........  OP7            ........  ...........  ........
tert-Butyl peroxybenzoate......  UN3109                    <=32      >=68  ........  ........  .........  OP8            ........  ...........  ........
tert-Butyl peroxybutyl fumarate  UN3105                    <=52      >=48  ........  ........  .........  OP7            ........  ...........  ........
tert-Butyl peroxycrotonate.....  UN3105                    <=77      >=23  ........  ........  .........  OP7            ........  ...........  ........
tert-Butyl peroxydiethylacetate  UN3113                   <=100  ........  ........  ........  .........  OP5                  20           25  ........
tert-Butyl peroxy-2-             UN3113                 >52-100  ........  ........  ........  .........  OP6                  20           25  ........
 ethylhexanoate.
tert-Butyl peroxy-2-             UN3117                  >32-52  ........      >=48  ........  .........  OP8                  30           35  ........
 ethylhexanoate.
tert-Butyl peroxy-2-             UN3118                    <=52  ........  ........      >=48  .........  OP8                  20           25  ........
 ethylhexanoate.
tert-Butyl peroxy-2-             UN3119                    <=32  ........      >=68  ........  .........  OP8                  40           45  ........
 ethylhexanoate.
tert-Butyl peroxy-2-             UN3106             <=12 + <=14      >=14  ........      >=60  .........  OP7            ........  ...........  ........
 ethylhexanoate [and] 2,2-di-
 (tert-Butylperoxy)butane.
tert-Butyl peroxy-2-             UN3115             <=31 + <=36  ........      >=33  ........  .........  OP7                  35           40  ........
 ethylhexanoate [and] 2,2-di-
 (tert-Butylperoxy)butane.
tert-Butyl peroxy-2-             UN3105                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 ethylhexylcarbonate.
tert-Butyl peroxyisobutyrate...  UN3111                  >52-77  ........      >=23  ........  .........  OP5                  15           20  ........
tert-Butyl peroxyisobutyrate...  UN3115                    <=52  ........      >=48  ........  .........  OP7                  15           20  ........
tert-Butylperoxy                 UN3103                    <=77      >=23  ........  ........  .........  OP5            ........  ...........  ........
 isopropylcarbonate.
tert-Butylperoxy                 UN3105                    <=62  ........     >= 38  ........  .........  OP7            ........  ...........  ........
 isopropylcarbonate.
1-(2-tert-Butylperoxy            UN3105                    <=77      >=23  ........  ........  .........  OP7            ........  ...........  ........
 isopropyl)-3-
 isopropenylbenzene.
1-(2-tert-Butylperoxy            UN3108                    <=42  ........  ........      >=58  .........  OP8            ........  ...........  ........
 isopropyl)-3-
 isopropenylbenzene.
tert-Butyl peroxy-2-             UN3103                   <=100  ........  ........  ........  .........  OP5            ........  ...........  ........
 methylbenzoate.
tert-Butyl peroxyneodecanoate..  UN3115                 >77-100  ........  ........  ........  .........  OP7                  -5            5  ........
tert-Butyl peroxyneodecanoate..  UN3115                    <=77  ........      >=23  ........  .........  OP7                   0           10  ........
tert-Butyl peroxyneodecanoate    UN3119                    <=52  ........  ........  ........  .........  OP8                   0           10  ........
 [as a stable dispersion in
 water].
tert-Butyl peroxyneodecanoate    UN3118                    <=42  ........  ........  ........  .........  OP8                   0           10  ........
 [as a stable dispersion in
 water (frozen)].
tert-Butyl peroxyneodecanoate..  UN3119                    <=32      >=68  ........  ........  .........  OP8                   0           10  ........
tert-Butyl peroxyneoheptanoate.  UN3115                    <=77      >=23  ........  ........  .........  OP7                   0           10  ........
tert-Butyl peroxyneoheptanoate   UN3117                    <=42  ........  ........  ........  .........  OP8                   0           10  ........
 [as a stable dispersion in
 water].
tert-Butyl peroxypivalate......  UN3113                  >67-77      >=23  ........  ........  .........  OP5                   0           10  ........
tert-Butyl peroxypivalate......  UN3115                  >27-67  ........      >=33  ........  .........  OP7                   0           10  ........
tert-Butyl peroxypivalate......  UN3119                    <=27  ........      >=73  ........  .........  OP8                  30           35  ........
tert-Butylperoxy                 UN3106                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 stearylcarbonate.
tert-Butyl peroxy-3,5,5-         UN3105                 >37-100  ........  ........  ........  .........  OP7            ........  ...........  ........
 trimethylhexanoate.
tert-Butyl peroxy-3,5,5-         UN3106                    <=42  ........  ........      >=58  .........  OP7            ........  ...........  ........
 trimethlyhexanoate.
tert-Butyl peroxy-3,5,5-         UN3109                    <=37  ........      >=63  ........  .........  OP8            ........  ...........  ........
 trimethylhexanoate.
3-Chloroperoxybenzoic acid.....  UN3102                  >57-86  ........  ........      >=14  .........  OP1            ........  ...........  ........
3-Chloroperoxybenzoic acid.....  UN3106                    <=57  ........  ........       >=3       >=40  OP7            ........  ...........  ........
3-Chloroperoxybenzoic acid.....  UN3106                    <=77  ........  ........       >=6       >=17  OP7            ........  ...........  ........
Cumyl hydroperoxide............  UN3107                  >90-98      <=10  ........  ........  .........  OP8            ........  ...........        13
Cumyl hydroperoxide............  UN3109                    <=90      >=10  ........  ........  .........  OP8            ........  ...........    13, 15
Cumyl peroxyneodecanoate.......  UN3115                    <=87      >=13  ........  ........  .........  OP7                 -10            0  ........
Cumyl peroxyneodecanoate.......  UN3115                    <=77  ........      >=23  ........  .........  OP7                 -10            0  ........
Cumyl peroxyneodecanoate [as a   UN3119                    <=52  ........  ........  ........  .........  OP8                 -10            0  ........
 stable dispersion in water].
Cumyl peroxyneoheptanoate......  UN3115                    <=77      >=23  ........  ........  .........  OP7                 -10            0  ........
Cumyl peroxypivalate...........  UN3115                    <=77  ........      >=23  ........  .........  OP7                  -5            5  ........
Cyclohexanone peroxide(s)......  UN3104                    <=91  ........  ........  ........        >=9  OP6            ........  ...........        13
Cyclohexanone peroxide(s)......  UN3105                    <=72      >=28  ........  ........  .........  OP7            ........  ...........         5
Cyclohexanone peroxide(s) [as a  UN3106                    <=72  ........  ........  ........  .........  OP7            ........  ...........     5, 21
 paste].
Cyclohexanone peroxide(s)......  Exempt                    <=32  ........       >68  ........  .........  Exempt         ........  ...........        29
Diacetone alcohol peroxides....  UN3115                    <=57  ........      >=26  ........        >=8  OP7                  40           45         5
Diacetyl peroxide..............  UN3115                    <=27  ........      >=73  ........  .........  OP7                  20           25      8,13
Di-tert-amyl peroxide..........  UN3107                   <=100  ........  ........  ........  .........  OP8            ........  ...........  ........
([3R- (3R, 5aS, 6S, 8aS, 9R,     UN3106                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 10R, 12S, 12aR**)]-Decahydro-
 10-methoxy-3, 6, 9-trimethyl-
 3, 12-epoxy-12H-pyrano [4, 3-
 j]-1, 2-benzodioxepin).
2,2-Di-(tert-amylperoxy)-butane  UN3105                    <=57      >=43  ........  ........  .........  OP7            ........  ...........  ........

[[Page 34615]]

 
1,1-Di-(tert-                    UN3103                    <=82      >=18  ........  ........  .........  OP6            ........  ...........  ........
 amylperoxy)cyclohexane.
Dibenzoyl peroxide.............  UN3102                 >52-100  ........  ........      <=48  .........  OP2            ........  ...........         3
Dibenzoyl peroxide.............  UN3102                  >77-94  ........  ........  ........        >=6  OP4            ........  ...........         3
Dibenzoyl peroxide.............  UN3104                    <=77  ........  ........  ........       >=23  OP6            ........  ...........  ........
Dibenzoyl peroxide.............  UN3106                    <=62  ........  ........      >=28       >=10  OP7            ........  ...........  ........
Dibenzoyl peroxide [as a paste]  UN3106                  >52-62  ........  ........  ........  .........  OP7            ........  ...........        21
Dibenzoyl peroxide.............  UN3106                  >35-52  ........  ........      >=48  .........  OP7            ........  ...........  ........
Dibenzoyl peroxide.............  UN3107                  >36-42      >=18  ........  ........       <=40  OP8            ........  ...........  ........
Dibenzoyl peroxide [as a paste]  UN3108                  <=56.5  ........  ........  ........       >=15  OP8            ........  ...........  ........
Dibenzoyl peroxide [as a paste]  UN3108                    <=52  ........  ........  ........  .........  OP8            ........  ...........        21
Dibenzoyl peroxide [as a stable  UN3109                    <=42  ........  ........  ........  .........  OP8            ........  ...........  ........
 dispersion in water].
Dibenzoyl peroxide.............  Exempt                    <=35  ........  ........      >=65  .........  Exempt         ........  ...........        29
Di-(4-tert-                      UN3114                   <=100  ........  ........  ........  .........  OP6                  30           35  ........
 butylcyclohexyl)peroxydicarbon
 ate.
Di-(4-tert-                      UN3119                    <=42  ........  ........  ........  .........  OP8                  30           35  ........
 butylcyclohexyl)peroxydicarbon
 ate [as a stable dispersion in
 water].
Di-(4-tert-                      UN3118                    <=42  ........  ........  ........  .........  OP8                  35           40  ........
 butylcyclohexyl)peroxydicarbon
 ate [as a paste].
Di-tert-butyl peroxide.........  UN3107                 >52-100  ........  ........  ........  .........  OP8            ........  ...........  ........
Di-tert-butyl peroxide.........  UN3109                    <=52  ........      >=48  ........  .........  OP8            ........  ...........        24
Di-tert-butyl peroxyazelate....  UN3105                    <=52      >=48  ........  ........  .........  OP7            ........  ...........  ........
2,2-Di-(tert-butylperoxy)butane  UN3103                    <=52      >=48  ........  ........  .........  OP6            ........  ...........  ........
1,6-Di-(tert-                    UN3103                    <=72      >=28  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxycarbonyloxy)hexane.
1,1-Di-(tert-                    UN3101                 >80-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3103                  >52-80      >=20  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-butylperoxy)-       UN3103                    <=72  ........      >=28  ........  .........  OP5            ........  ...........        30
 cyclohexane.
1,1-Di-(tert-                    UN3105                  >42-52      >=48  ........  ........  .........  OP7            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3106                    <=42      >=13  ........      >=45  .........  OP7            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3107                    <=27      >=25  ........  ........  .........  OP8            ........  ...........        22
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3109                    <=42      >=58  ........  ........  .........  OP8            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3109                    <=37      >=63  ........  ........  .........  OP8            ........  ...........  ........
 Butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3109                    <=25      >=25      >=50  ........  .........  OP8            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3109                    <=13      >=13      >=74  ........  .........  OP8            ........  ...........  ........
 butylperoxy)cyclohexane.
1,1-Di-(tert-                    UN3105               <=43+<=16      >=41  ........  ........  .........  OP7            ........  ...........  ........
 butylperoxy)cyclohexane + tert-
 Butyl peroxy-2-ethylhexanoate.
Di-n-butyl peroxydicarbonate...  UN3115                  >27-52  ........      >=48  ........  .........  OP7                 -15           -5  ........
Di-n-butyl peroxydicarbonate...  UN3117                    <=27  ........      >=73  ........  .........  OP8                 -10            0  ........
Di-n-butyl peroxydicarbonate     UN3118                    <=42  ........  ........  ........  .........  OP8                 -15           -5  ........
 [as a stable dispersion in
 water (frozen)].
Di-sec-butyl peroxydicarbonate.  UN3113                 >52-100  ........  ........  ........  .........  OP4                 -20          -10         6
Di-sec-butyl peroxydicarbonate.  UN3115                    <=52  ........      >=48  ........  .........  OP7                 -15           -5  ........
Di-(tert-butylperoxyisopropyl)   UN3106                 >42-100  ........  ........      <=57  .........  OP7            ........  ...........      1, 9
 benzene(s).
Di-(tert-butylperoxyisopropyl)   Exempt                    <=42  ........  ........      >=58  .........  Exempt         ........  ...........  ........
 benzene(s).
Di-(tert-butylperoxy)phthalate.  UN3105                  >42-52      >=48  ........  ........  .........  OP7            ........  ...........  ........
Di-(tert-butylperoxy)phthalate   UN3106                    <=52  ........  ........  ........  .........  OP7            ........  ...........        21
 [as a paste].
Di-(tert-butylperoxy)phthalate.  UN3107                    <=42      >=58  ........  ........  .........  OP8            ........  ...........  ........
2,2-Di-(tert-                    UN3105                    <=52      >=48  ........  ........  .........  OP7            ........  ...........  ........
 butylperoxy)propane.
2,2-Di-(tert-                    UN3106                    <=42      >=13  ........      >=45  .........  OP7            ........  ...........  ........
 butylperoxy)propane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3101                 >90-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3103                  >57-90      >=10  ........  ........  .........  OP5            ........  ...........  ........
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3103                    <=77  ........      >=23  ........  .........  OP5            ........  ...........  ........
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3103                    <=90  ........      >=10  ........  .........  OP5            ........  ...........        30
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3110                    <=57  ........  ........      >=43  .........  OP8            ........  ...........  ........
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3107                    <=57      >=43  ........  ........  .........  OP8            ........  ...........  ........
 trimethylcyclohexane.
1,1-Di-(tert-butylperoxy)-3,3,5- UN3107                    <=32      >=26      >=42  ........  .........  OP8            ........  ...........  ........
 trimethylcyclohexane.
Dicetyl peroxydicarbonate......  UN3120                   <=100  ........  ........  ........  .........  OP8                  30           35  ........
Dicetyl peroxydicarbonate [as a  UN3119                    <=42  ........  ........  ........  .........  OP8                  30           35  ........
 stable dispersion in water].
Di-4-chlorobenzoyl peroxide....  UN3102                    <=77  ........  ........  ........       >=23  OP5            ........  ...........  ........
Di-4-chlorobenzoyl peroxide....  Exempt                    <=32  ........  ........      >=68  .........  Exempt         ........  ...........        29
Di-2,4-dichlorobenzoyl peroxide  UN3118                    <=52  ........  ........  ........  .........  OP8                  20           25  ........
 [as a paste].
Di-4-chlorobenzoyl peroxide [as  UN3106                    <=52  ........  ........  ........  .........  OP7            ........  ...........        21
 a paste].
Dicumyl peroxide...............  UN3110                 >52-100  ........  ........      <=48  .........  OP8            ........  ...........         9

[[Page 34616]]

 
Dicumyl peroxide...............  Exempt                    <=52  ........  ........      >=48  .........  Exempt         ........  ...........        29
Dicyclohexyl peroxydicarbonate.  UN3112                 >91-100  ........  ........  ........  .........  OP3                  10           15  ........
Dicyclohexyl peroxydicarbonate.  UN3114                    <=91  ........  ........  ........        >=9  OP5                  10           15  ........
Dicyclohexyl peroxydicarbonate   UN3119                    <=42  ........  ........  ........  .........  OP8                  15           20  ........
 [as a stable dispersion in
 water].
Didecanoyl peroxide............  UN3114                   <=100  ........  ........  ........  .........  OP6                  30           35  ........
2,2-Di-(4,4-di(tert-             UN3106                    <=42  ........  ........      >=58  .........  OP7            ........  ...........  ........
 butylperoxy)cyclohexyl)propane.
2,2-Di-(4,4-di(tert-             UN3107                    <=22  ........      >=78  ........  .........  OP8            ........  ...........  ........
 butylperoxy)cyclohexyl)propane.
Di-2,4-dichlorobenzoyl peroxide  UN3102                    <=77  ........  ........  ........       >=23  OP5            ........  ...........  ........
Di-2,4-dichlorobenzoyl peroxide  UN3106                    <=52  ........  ........  ........  .........  OP7            ........  ...........  ........
 [as a paste with silicone oil].
Di-(2-ethoxyethyl)               UN3115                    <=52  ........      >=48  ........  .........  OP7                 -10            0  ........
 peroxydicarbonate.
Di-(2-ethylhexyl)                UN3113                 >77-100  ........  ........  ........  .........  OP5                 -20          -10  ........
 peroxydicarbonate.
Di-(2-ethylhexyl)                UN3115                    <=77  ........      >=23  ........  .........  OP7                 -15           -5  ........
 peroxydicarbonate.
Di-(2-ethylhexyl)                UN3119                    <=62  ........  ........  ........  .........  OP8                 -15           -5  ........
 peroxydicarbonate [as a stable
 dispersion in water].
Di-(2-ethylhexyl)                UN3119                    <=52  ........  ........  ........  .........  OP8                 -15           -5  ........
 peroxydicarbonate [as a stable
 dispersion in water].
Di-(2-ethylhexyl)                UN3120                    <=52  ........  ........  ........  .........  OP8                 -15           -5  ........
 peroxydicarbonate [as a stable
 dispersion in water (frozen)].
2,2-Dihydroperoxypropane.......  UN3102                    <=27  ........  ........      >=73  .........  OP5            ........  ...........  ........
Di-(1-                           UN3106                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 hydroxycyclohexyl)peroxide.
Diisobutyryl peroxide..........  UN3111                  >32-52  ........      >=48  ........  .........  OP5                 -20          -10  ........
Diisobutyryl peroxide [as a      UN3119                    <=42  ........  ........  ........  .........  OP8                 -20          -10  ........
 stable dispersion in water].
Diisobutyryl peroxide..........  UN3115                    <=32  ........      >=68  ........  .........  OP7                 -20          -10  ........
Diisopropylbenzene               UN3106                    <=82       >=5  ........  ........        >=5  OP7            ........  ...........        17
 dihydroperoxide.
Diisopropyl peroxydicarbonate..  UN3112                 >52-100  ........  ........  ........  .........  OP2                 -15           -5  ........
Diisopropyl peroxydicarbonate..  UN3115                    <=52  ........      >=48  ........  .........  OP7                 -20          -10  ........
Diisopropyl peroxydicarbonate..  UN3115                    <=32      >=68  ........  ........  .........  OP7                 -15           -5  ........
Dilauroyl peroxide.............  UN3106                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
Dilauroyl peroxide [as a stable  UN3109                    <=42  ........  ........  ........  .........  OP8            ........  ...........  ........
 dispersion in water].
Di-(3-methoxybutyl)              UN3115                    <=52  ........      >=48  ........  .........  OP7                  -5            5  ........
 peroxydicarbonate.
Di-(2-methylbenzoyl)peroxide...  UN3112                    <=87  ........  ........  ........       >=13  OP5                  30           35  ........
Di-(4-methylbenzoyl)peroxide     UN3106                    <=52  ........  ........  ........  .........  OP7            ........  ...........  ........
 [as a paste with silicone oil].
Di-(3-methylbenzoyl) peroxide +  UN3115           <=20 + <=18 +  ........      >=58  ........  .........  OP7                  35           40  ........
 Benzoyl (3-methylbenzoyl)                                  <=4
 peroxide + Dibenzoyl peroxide.
2,5-Dimethyl-2,5-di-             UN3102                 >82-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 (benzoylperoxy)hexane.
2,5-Dimethyl-2,5-di-             UN3106                    <=82  ........  ........      >=18  .........  OP7            ........  ...........  ........
 (benzoylperoxy)hexane.
2,5-Dimethyl-2,5-di-             UN3104                    <=82  ........  ........  ........       >=18  OP5            ........  ...........  ........
 (benzoylperoxy)hexane.
2,5-Dimethyl-2,5-di-(tert-       UN3103                 >90-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)hexane.
2,5-Dimethyl-2,5-di-(tert-       UN3105                  >52-90      >=10  ........  ........  .........  OP7            ........  ...........  ........
 butylperoxy)hexane.
2,5-Dimethyl-2,5-di-(tert-       UN3108                    <=77  ........  ........      >=23  .........  OP8            ........  ...........  ........
 butylperoxy)hexane.
2,5-Dimethyl-2,5-di-(tert-       UN3109                    <=52      >=48  ........  ........  .........  OP8            ........  ...........  ........
 butylperoxy)hexane.
2,5-Dimethyl-2,5-di-(tert-       UN3108                    <=47  ........  ........  ........  .........  OP8            ........  ...........  ........
 butylperoxy)hexane [as a
 paste].
2,5-Dimethyl-2,5-di-(tert-       UN3101                 >86-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)hexyne-3.
2,5-Dimethyl-2,5-di-(tert-       UN3103                  >52-86      >=14  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)hexyne-3.
2,5-Dimethyl-2,5-di-(tert-       UN3106                    <=52  ........  ........      >=48  .........  OP7            ........  ...........  ........
 butylperoxy)hexyne-3.
2,5-Dimethyl-2,5-di-(2-          UN3113                   <=100  ........  ........  ........  .........  OP5                  20           25  ........
 ethylhexanoylperoxy)hexane.
2,5-Dimethyl-2,5-                UN3104                    <=82  ........  ........  ........       >=18  OP6            ........  ...........  ........
 dihydroperoxyhexane.
2,5-Dimethyl-2,5-di-(3,5,5-      UN3105                    <=77      >=23  ........  ........  .........  OP7            ........  ...........  ........
 trimethylhexanoylperoxy)hexane.
1,1-Dimethyl-3-                  UN3117                    <=52      >=48  ........  ........  .........  OP8                   0           10  ........
 hydroxybutylperoxyneoheptanoat
 e.
Dimyristyl peroxydicarbonate...  UN3116                   <=100  ........  ........  ........  .........  OP7                  20           25  ........
Dimyristyl peroxydicarbonate     UN3119                    <=42  ........  ........  ........  .........  OP8                  20           25  ........
 [as a stable dispersion in
 water].
Di-(2-                           UN3115                    <=52      >=48  ........  ........  .........  OP7                 -10            0  ........
 neodecanoylperoxyisopropyl)ben
 zene.

[[Page 34617]]

 
Di-(2-neodecanoyl-               UN3119                    <=42  ........  ........  ........  .........  OP8                 -15           -5  ........
 peroxyisopropyl) benzene, as
 stable dispersion in water.
Di-n-nonanoyl peroxide.........  UN3116                   <=100  ........  ........  ........  .........  OP7                   0           10  ........
Di-n-octanoyl peroxide.........  UN3114                   <=100  ........  ........  ........  .........  OP5                  10           15  ........
Di-(2-                           UN3102                 >85-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 phenoxyethyl)peroxydicarbonate.
Di-(2-                           UN3106                    <=85  ........  ........  ........       >=15  OP7            ........  ...........  ........
 phenoxyethyl)peroxydicarbonate.
Dipropionyl peroxide...........  UN3117                    <=27  ........      >=73  ........  .........  OP8                  15           20  ........
Di-n-propyl peroxydicarbonate..  UN3113                   <=100  ........  ........  ........  .........  OP3                 -25          -15  ........
Di-n-propyl peroxydicarbonate..  UN3113                    <=77  ........      >=23  ........  .........  OP5                 -20          -10  ........
Disuccinic acid peroxide.......  UN3102                 >72-100  ........  ........  ........  .........  OP4            ........  ...........        18
Disuccinic acid peroxide.......  UN3116                    <=72  ........  ........  ........       >=28  OP7                  10           15  ........
Di-(3,5,5-trimethylhexanoyl)     UN3115                  >52-82      >=18  ........  ........  .........  OP7                   0           10  ........
 peroxide.
Di-(3,5,5-                       UN3119                    <=52  ........  ........  ........  .........  OP8                  10           15  ........
 trimethylhexanoyl)peroxide [as
 a stable dispersion in water].
Di-(3,5,5-trimethylhexanoyl)     UN3119                  >38-52      >=48  ........  ........  .........  OP8                  10           15  ........
 peroxide.
Di-(3,5,5-                       UN3119                    <=38      >=62  ........  ........  .........  OP8                  20           25  ........
 trimethylhexanoyl)peroxide.
Ethyl 3,3-di-(tert-              UN3105                    <=67      >=33  ........  ........  .........  OP7            ........  ...........  ........
 amylperoxy)butyrate.
Ethyl 3,3-di-(tert-              UN3103                 >77-100  ........  ........  ........  .........  OP5            ........  ...........  ........
 butylperoxy)butyrate.
Ethyl 3,3-di-(tert-              UN3105                    <=77      >=23  ........  ........  .........  OP7            ........  ...........  ........
 butylperoxy)butyrate.
Ethyl 3,3-di-(tert-              UN3106                    <=52  ........  ........      >=48  .........  OP7            ........  ...........  ........
 butylperoxy)butyrate.
1-(2-ethylhexanoylperoxy)-1,3-   UN3115                    <=52      >=45      >=10  ........  .........  OP7                 -20          -10  ........
 Dimethylbutyl peroxypivalate.
tert-Hexyl peroxyneodecanoate..  UN3115                    <=71      >=29  ........  ........  .........  OP7                   0           10  ........
tert-Hexyl peroxypivalate......  UN3115                    <=72  ........      >=28  ........  .........  OP7                  10           15  ........
tert-Hexyl peroxypivalate......  UN3117               <=52 as a  ........  ........  ........  .........  OP8                 +15          +20  ........
                                                         stable
                                                  dispersion in
                                                          water
3-Hydroxy-1,1-dimethylbutyl      UN3115                    <=77      >=23  ........  ........  .........  OP7                  -5            5  ........
 peroxyneodecanoate.
3-Hydroxy-1,1-dimethylbutyl      UN3119                    <=52  ........  ........  ........  .........  OP8                  -5            5  ........
 peroxyneodecanoate [as a
 stable dispersion in water].
3-Hydroxy-1,1-dimethylbutyl      UN3117                    <=52      >=48  ........  ........  .........  OP8                  -5            5  ........
 peroxyneodecanoate.
Isopropyl sec-butyl              UN3111           <=52 + <=28 +  ........  ........  ........  .........  OP5                 -20          -10  ........
 peroxydicarbonat + Di-sec-                                <=22
 butyl peroxydicarbonate + Di-
 isopropyl peroxydicarbonate.
Isopropyl sec-butyl              UN3115         <=32 + <=15 -18      >=38  ........  ........  .........  OP7                 -20          -10  ........
 peroxydicarbonate + Di-sec-                         + <=12 -15
 butyl peroxydicarbonate + Di-
 isopropyl peroxydicarbonate.
Isopropylcumyl hydroperoxide...  UN3109                    <=72      >=28  ........  ........  .........  OP8            ........  ...........        13
p-Menthyl hydroperoxide........  UN3105                 >72-100  ........  ........  ........  .........  OP7            ........  ...........        13
p-Menthyl hydroperoxide........  UN3109                    <=72      >=28  ........  ........  .........  OP8            ........  ...........  ........
Methylcyclohexanone peroxide(s)  UN3115                    <=67  ........      >=33  ........  .........  OP7                  35           40  ........
Methyl ethyl ketone peroxide(s)  UN3101                    <=52      >=48  ........  ........  .........  OP5            ........  ...........     5, 13
Methyl ethyl ketone peroxide(s)  UN3105                    <=45      >=55  ........  ........  .........  OP7            ........  ...........         5
Methyl ethyl ketone peroxide(s)  UN3107                    <=40      >=60  ........  ........  .........  OP8            ........  ...........         7
Methyl isobutyl ketone           UN3105                    <=62      >=19  ........  ........  .........  OP7            ........  ...........     5, 23
 peroxide(s).
Methyl isopropyl ketone          UN3109         (See remark 31)      >=70  ........  ........  .........  OP8            ........  ...........        31
 peroxide(s).
Organic peroxide, liquid,        UN3103         ...............  ........  ........  ........  .........  OP2            ........  ...........        12
 sample.
Organic peroxide, liquid,        UN3113         ...............  ........  ........  ........  .........  OP2            ........  ...........        12
 sample, temperature controlled.
Organic peroxide, solid, sample  UN3104         ...............  ........  ........  ........  .........  OP2            ........  ...........        12
Organic peroxide, solid,         UN3114         ...............  ........  ........  ........  .........  OP2            ........  ...........        12
 sample, temperature controlled.
3,3,5,7,7-Pentamethyl-1,2,4-     UN3107                   <=100  ........  ........  ........  .........  OP8            ........  ...........  ........
 Trioxepane.
Peroxyacetic acid, type D,       UN3105                    <=43  ........  ........  ........  .........  OP7            ........  ...........    13, 20
 stabilized.
Peroxyacetic acid, type E,       UN3107                    <=43  ........  ........  ........  .........  OP8            ........  ...........    13, 20
 stabilized.
Peroxyacetic acid, type F,       UN3109                    <=43  ........  ........  ........  .........  OP8            ........  ...........   13, 20,
 stabilized.                                                                                                                                          28
Peroxyacetic acid or peracetic   UN3107                    <=36  ........  ........  ........       >=15  OP8            ........  ...........   13, 20,
 acid [with not more than 7%                                                                                                                          28
 hydrogen peroxide].
Peroxyacetic acid or peracetic   Exempt                     <=6  ........  ........  ........       >=60  Exempt         ........  ...........        28
 acid [with not more than 20%
 hydrogen peroxide].
Peroxyacetic acid or peracetic   UN3109                    <=17  ........  ........  ........  .........  OP8            ........  ...........   13, 20,
 acid [with not more than 26%                                                                                                                         28
 hydrogen peroxide].
Peroxylauric acid..............  UN3118                   <=100  ........  ........  ........  .........  OP8                  35           40  ........
1-Phenylethyl hydroperoxide....  UN3109                    <=38  ........      >=62  ........  .........  OP8            ........  ...........  ........
Pinanyl hydroperoxide..........  UN3105                 >56-100  ........  ........  ........  .........  OP7            ........  ...........        13
Pinanyl hydroperoxide..........  UN3109                    <=56      >=44  ........  ........  .........  OP8            ........  ...........  ........
Polyether poly-tert-             UN3107                    <=52  ........      >=48  ........  .........  OP8            ........  ...........  ........
 butylperoxycarbonate.
Tetrahydronaphthyl               UN3106                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 hydroperoxide.
1,1,3,3-Tetramethylbutyl         UN3105                   <=100  ........  ........  ........  .........  OP7            ........  ...........  ........
 hydroperoxide.

[[Page 34618]]

 
1,1,3,3-Tetramethylbutyl peroxy- UN3115                   <=100  ........  ........  ........  .........  OP7                  15           20  ........
 2-ethylhexanoate.
1,1,3,3-Tetramethylbutyl         UN3115                    <=72  ........      >=28  ........  .........  OP7                  -5            5  ........
 peroxyneodecanoate.
1,1,3,3-Tetramethylbutyl         UN3119                    <=52  ........  ........  ........  .........  OP8                  -5            5  ........
 peroxyneodecanoate [as a
 stable dispersion in water].
1,1,3,3-tetramethylbutyl         UN3115                    <=77      >=23  ........  ........  .........  OP7                   0           10  ........
 peroxypivalate.
3,6,9-Triethyl-3,6,9-trimethyl-  UN3110                    <=17      >=18  ........      >=65  .........  OP8            ........  ...........  ........
 1,4,7-triperoxonane.
3,6,9-Triethyl-3,6,9-trimethyl-  UN3105                    <=42      >=58  ........  ........  .........  OP7            ........  ...........        26
 1,4,7-triperoxonane.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
1. For domestic shipments, OP8 is authorized.
2. Available oxygen must be <4.7%.
3. For concentrations <80% OP5 is allowed. For concentrations of at least 80% but <85%, OP4 is allowed. For concentrations of at least 85%, maximum
  package size is OP2.
4. The diluent may be replaced by di-tert-butyl peroxide.
5. Available oxygen must be <=9% with or without water.
6. For domestic shipments, OP5 is authorized.
7. Available oxygen must be <=8.2% with or without water.
8. Only non-metallic packagings are authorized.
9. For domestic shipments this material may be transported under the provisions of paragraph (h)(3)(xii) of this section.
10. [Reserved]
11. [Reserved]
12. Samples may only be offered for transportation under the provisions of paragraph (b)(2) of this section.
13. ``Corrosive'' subsidiary risk label is required.
14. [Reserved]
15. No ``Corrosive'' subsidiary risk label is required for concentrations below 80%.
16. With <6% di-tert-butyl peroxide.
17. With <=8% 1-isopropylhydroperoxy-4-isopropylhydroxybenzene.
18. Addition of water to this organic peroxide will decrease its thermal stability.
19. [Reserved]
20. Mixtures with hydrogen peroxide, water, and acid(s).
21. With diluent type A, with or without water.
22. With >=36%% diluent type A by mass, and in addition ethylbenzene.
23. With >=19% diluent type A by mass, and in addition methyl isobutyl ketone.
24. Diluent type B with boiling point >100 [deg]C.
25. No ``Corrosive'' subsidiary risk label is required for concentrations below 56%.
26. Available oxygen must be <=7.6%
27. Formulations derived from distillation of peroxyacetic acid originating from peroxyacetic acid in a concentration of not more than 41% with water,
  total active oxygen less than or equal to 9.5% (peroxyacetic acid plus hydrogen peroxide).
28. For the purposes of this section, the names ``Peroxyacetic acid'' and ``Peracetic acid'' are synonymous.
29. Not subject to the requirements of this subchapter for Division 5.2.
30. Diluent type B with boiling point >130 [deg]C (266 [deg]F).
31. Available oxygen <=6.7%.
32. Active oxygen concentration <=4.15%.

* * * * *
    (g) * * *

                                                                 Table 4 to Paragraph (g): Organic Peroxide Portable Tank Table
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                 Minimum shell
                                                              Minimum test      thickness  (mm-       Bottom opening        Pressure-relief                               Control     Emergency
               UN No.                  Hazardous  material   pressure (bar)    reference steel)     requirements  See .   requirements  See .      Filling limits       temperature  temperature
                                                                                   See . . .                . .                   . .
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3109...............................  ORGANIC PEROXIDE,.....  ..............  ....................  ....................  ....................  ......................  ............  ...........
                                     TYPE F, LIQUID........
 
                                                                                          * * * * * * *
                                     tert-Butyl                           4  Sec.   178.274(d)(2)  Sec.   178.275(d)(3)  Sec.   178.275(g)(1)  Not more than 90% at    ............  ...........
                                      hydroperoxide, not                                                                                        59 [deg]F (15 [deg]C).
                                      more than 56% with
                                      diluent type B \2\.
 
                                                                                          * * * * * * *
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes
1. ``Corrosive'' subsidiary risk placard is required.
2. Diluent type B is tert-Butyl alcohol.

[[Page 34619]]

0
19. In Sec.  173.232, add paragraph (h) to read as follows:

Sec.  173.232  Articles containing hazardous materials, n.o.s.

* * * * *
    (h) For transport by aircraft, the following additional 
requirements apply:
    (i) Articles transported under UN3548, which do not have an 
existing proper shipping name, and which contain only environmentally 
hazardous substances where the quantity of the environmentally 
hazardous substance in the article exceeds 5 L or 5 kg, must be 
prepared for transport in accordance with this section for transport by 
air. In addition to the environmentally hazardous substances, the 
article may also contain lithium cells or batteries that comply with 
Sec.  173.185(c)(4), as applicable.
    (ii) Articles transported under UN3538, which do not have an 
existing proper shipping name, and which contain only gases of Division 
2.2 without a subsidiary hazard, but excluding refrigerated liquefied 
gases and gases forbidden for transport on passenger aircraft, where 
the quantity of the Division 2.2 gas exceeds the quantity limits for UN 
3363, as prescribed in Sec.  173.222 must be prepared for transport in 
accordance with this section. Articles transported under this provision 
are limited to a maximum net quantity of gas of 75 kg by passenger 
aircraft and 150 kg by cargo aircraft. In addition to the Division 2.2 
gas, the article may also contain lithium cells or batteries that 
comply with Sec.  173.185(c)(4), as applicable.
0
20. In Sec.  173.301b, revise paragraphs (c)(1), (c)(2)(ii) through 
(iv), (d)(1), and (f) to read as follows:

Sec.  173.301b  Additional general requirements for shipment of UN 
pressure receptacles.

* * * * *
    (c) * * *
    (1) When the use of a valve is prescribed, the valve must conform 
to the requirements in ISO 10297:2014(E) and ISO 10297:2014/Amd 1:2017 
(IBR, see Sec.  171.7 of this subchapter). Quick release cylinder 
valves for specification and type testing must conform to the 
requirements in ISO 17871:2020 or, until December 31, 2026, ISO 
17871:2015(E) (IBR, see Sec.  171.7 of this subchapter). Until December 
31, 2026, a quick release valve conforming to the requirements in ISO 
17871:2015(E) (IBR, see Sec.  171.7 of this subchapter) continues to be 
authorized for use.
    (2) * * *
    (ii) By equipping the UN pressure receptacle with a valve cap 
conforming to the requirements in ISO 11117:2019 (IBR, see Sec.  171.7 
of this subchapter). Until December 31, 2026, the UN pressure 
receptacle may continue to be equipped with a valve cap conforming to 
the requirements in ISO 11117:2008(E) and Technical Corrigendum 1 (IBR, 
see Sec.  171.7 of this subchapter);
    (iii) By protecting the valves with shrouds or guards conforming to 
the requirements in ISO 11117:2019 (IBR; see Sec.  171.7 of this 
subchapter). Until December 31, 2026, the valves may continue to be 
protected by shrouds or guards conforming to the requirements in ISO 
11117:2008 and Technical Corrigendum 1 (IBR; see Sec.  171.7 of this 
subchapter). For metal hydride storage systems, by protecting the 
valves in accordance with the requirements in ISO 16111:2018(E) or, 
until December 31, 2026, in accordance with ISO 16111:2008(E) (IBR; see 
Sec.  171.7 of this subchapter).
    (iv) By using valves designed and constructed with sufficient 
inherent strength to withstand damage, in accordance with Annex B of 
ISO 10297:2014(E)/Amd. 1:2017 (IBR; see Sec.  171.7 of this 
subchapter);
* * * * *
    (d) Non-refillable UN pressure receptacles. (1) When the use of a 
valve is prescribed, the valve must conform to the requirements in ISO 
11118:2015(E) and ISO 11118:2015/Amd 1:2019 until further notice. 
Conformance with ISO 11118:2015 without the supplemental amendment is 
authorized until December 31, 2026 (IBR, see Sec.  171.7 of this 
subchapter).
* * * * *
    (f) Hydrogen bearing gases. A steel UN pressure receptacle or a UN 
composite pressure receptacle with a steel liner bearing an ``H'' mark 
must be used for hydrogen bearing gases or other embrittling gases that 
have the potential of causing hydrogen embrittlement.
* * * * *
0
21. In Sec.  173.302c, revise paragraph (k) to read as follows:

Sec.  173.302c  Additional requirements for the shipment of adsorbed 
gases in UN pressure receptacles.

* * * * *
    (k) The filling procedure must be in accordance with Annex A of ISO 
11513:2019 (IBR, see Sec.  171.7 of this subchapter). Until December 
31, 2026, filling may instead be in accordance with Annex A of ISO 
11513:2011(E) (IBR, see Sec.  171.7 of this subchapter).
* * * * *
0
22. Revise Sec.  173.311 to read as follows:

Sec.  173.311  Metal Hydride Storage Systems.

    The following packing instruction is applicable to transportable UN 
Metal hydride storage systems (UN3468) with pressure receptacles not 
exceeding 150 liters (40 gallons) in water capacity and having a 
maximum developed pressure not exceeding 25 MPa. UN Metal hydride 
storage systems must be designed, constructed, initially inspected, and 
tested in accordance with ISO 16111:2018 (IBR, see Sec.  171.7 of this 
subchapter), consistent with Sec.  178.71(m) of this subchapter. Until 
December 31, 2026, UN Metal hydride storage systems may instead conform 
to ISO 16111:2008(E) (IBR, see Sec.  171.7 of this subchapter). Steel 
pressure receptacles or composite pressure receptacles with steel 
liners must be marked in accordance with Sec.  173.301b(f), which 
specifies that a steel UN pressure receptacle displaying an ``H'' mark 
must be used for hydrogen-bearing gases or other gases that may cause 
hydrogen embrittlement. Requalification intervals must be no more than 
every five years, as specified in Sec.  180.207 of this subchapter, in 
accordance with the requalification procedures prescribed in ISO 
16111:2018 or ISO 16111:2008.
* * * * *

PART 175--CARRIAGE BY AIRCRAFT

0
23. The authority citation for part 175 continues to read as follows:

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

0
24. In Sec.  175.1, add paragraph (e) to read as follows:

Sec.  175.1  Purpose, scope, and applicability.

* * * * *
    (e) In addition to the requirements of this part, air carriers that 
are certificate holders authorized to conduct operations in accordance 
with 14 CFR part 121 are also required to have a Safety Management 
System meeting the conditions of 14 CFR part 5 and found to be 
acceptable to the Federal Aviation Administration (FAA).
0
25. In Sec.  175.10, revise paragraphs (a) introductory text, (a)(14) 
introductory text, (a)(15)(v)(A), (a)(15)(vi)(A), (a)(17)(ii)(C), 
(a)(18) introductory text, and (a)(26) introductory text to read as 
follows:

Sec.  175.10  Exceptions for passengers, crewmembers, and air 
operators.

* * * * *
    (a) This subchapter does not apply to the following hazardous 
materials when

[[Page 34620]]

carried by aircraft passengers or crewmembers provided the requirements 
of Sec. Sec.  171.15 and 171.16 of this subchapter (see paragraph (c) 
of this section) and the requirements of this section are met. The most 
appropriate description of the hazardous material item or article must 
be selected and the associated conditions for exception must be 
followed:
* * * * *
    (14) Battery powered heat-producing devices (e.g., battery-operated 
equipment such as diving lamps and soldering equipment) as checked or 
carry-on baggage and with the approval of the operator of the aircraft. 
The heating element, the battery, or other component (e.g., fuse) must 
be isolated to prevent unintentional activation during transport. Any 
battery that is removed must be carried in accordance with the 
provisions for spare batteries in paragraph (a)(18) of this section. 
Each battery must be of a type which meets the requirements of each 
test in the UN Manual of Tests and Criteria, Part III, Subsection 38.3 
(IBR, see Sec.  171.7 of this subchapter), and each installed or spare 
lithium battery:
* * * * *
    (15) * * *
    (v) * * *
    (A) Adequately protected against damage by design of the wheelchair 
or mobility aid and securely attached to the wheelchair or mobility 
aid; or
* * * * *
    (vi) * * *
    (A) Adequately protected against damage by design of the wheelchair 
or mobility aid and securely attached to the wheelchair or mobility 
aid; or
* * * * *
    (17) * * *
    (ii) * * *
    (C) The battery is adequately protected against damage by design of 
the wheelchair or mobility aid and securely attached to the wheelchair 
or other mobility aid; and
* * * * *
    (18) Except as provided in Sec.  173.21 of this subchapter, 
portable electronic devices (e.g., watches, calculating machines, 
cameras, cellular phones, laptop and notebook computers, camcorders, 
medical devices, etc.) that are not otherwise more appropriately 
described and subject to separate provisions in this section, 
containing dry cells or dry batteries (including lithium cells or 
batteries) and spare dry cells or batteries for these devices, when 
carried by passengers or crew members for personal use. Portable 
electronic devices powered by lithium batteries may be carried in 
either checked or carry-on baggage. When carried in checked baggage, 
portable electronic devices powered by lithium batteries must be 
completely switched off (i.e., not in sleep or hibernation mode) and 
protected to prevent unintentional activation or damage, except 
portable electronic devices powered by lithium batteries with lithium 
content not exceeding 0.3 grams for lithium metal batteries and 2.7 Wh 
for lithium ion batteries are not required to be switched off. Spare 
lithium batteries must be carried in carry-on baggage only. Each 
installed or spare lithium battery must be of a type proven to meet the 
requirements of each test in the UN Manual of Tests and Criteria, Part 
III, Sub-section 38.3, and each spare lithium battery must be 
individually protected so as to prevent short circuits (e.g., by 
placement in original retail packaging, by otherwise insulating 
terminals by taping over exposed terminals, or placing each battery in 
a separate plastic bag or protective pouch). In addition, each 
installed or spare lithium battery:
* * * * *
    (26) Baggage equipped with lithium batteries must be carried as 
carry-on baggage unless the batteries are removed from the baggage. 
Batteries must be of a type which meets the requirements of each test 
in the UN Manual of Tests and Criteria, Part III, Subsection 38.3 (IBR, 
see Sec.  171.7 of this subchapter). Additionally, removed batteries 
must be carried in accordance with the provision for spare batteries 
prescribed in paragraph (a)(18) of this section. Baggage equipped with 
lithium batteries may be carried as checked baggage and electronic 
features may remain active if the batteries do not exceed:
* * * * *
0
26. In Sec.  175.33, revise paragraph (a)(13)(iii) to read as follows:

Sec.  175.33  Shipping paper and information to the pilot-in-command.

    (a) * * *
    (13) * * *
    (iii) UN3481 and UN3091 are not required to appear on the 
information provided to the pilot-in-command when prepared in 
accordance with Sec.  173.185(c)(4).
* * * * *

PART 178--SPECIFICATIONS FOR PACKAGINGS

0
27. The authority citation for part 178 continues to read as follows:

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

0
28. In Sec.  178.37, revise paragraph (j) to read as follows:

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

* * * * *
    (j) Flattening test. A flattening test must be performed on one 
cylinder, taken at random out of each lot of 200 or fewer, by placing 
the cylinder between wedge shaped knife edges, having a 60-degree 
included angle, rounded to \1/2\-inch radius. The longitudinal axis of 
the cylinder must be at a 90-degree angle to the knife edges during the 
test. For lots of 30 or fewer, flattening tests are authorized to be 
made on a ring at least eight (8) inches long, cut from each cylinder 
and subjected to the same heat treatment as the finished cylinder. 
Cylinders may be subjected to a bend test in lieu of the flattening 
test. Two bend test specimens must be taken in accordance with ISO 
9809-1:2019(E) or ASTM E290 (IBR, see Sec.  171.7 of this subchapter), 
and must be subjected to the bend test specified therein.
* * * * *
0
29. In Sec.  178.71, revise paragraphs (f)(4), (g), (i), (k)(1)(i) and 
(ii), (m), and (n) to read as follows:

Sec.  178.71  Specifications for UN pressure receptacles.

* * * * *
    (f) * * *
    (4) ISO 21172-1:2015(E) Gas cylinders--Welded steel pressure drums 
up to 3,000 litres capacity for the transport of gases--Design and 
construction--Part 1: Capacities up-to 1,000 litres (IBR, see Sec.  
171.7 of this subchapter) in combination with ISO 21172-1:2015/Amd 
1:2018(E)--Gas Cylinders--Welded steel pressure drums up to 3,000 
litres capacity for the transport of gases--Design and construction--
Part 1: Capacities up-to 1,000 litres--Amendment 1 (IBR, see Sec.  
171.7 of this subchapter).Until December 31, 2026, the use of ISO 
21172-1:2015 (IBR, see Sec.  171.7 of this subchapter) without the 
supplemental amendment is authorized.
* * * * *
    (g) Design and construction requirements for UN refillable seamless 
steel cylinders. In addition to the general requirements of this 
section, UN refillable seamless steel cylinders must conform to the 
following ISO standards, as applicable:
    (1) ISO 9809-1:2019(E), Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction, and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1100 MPa (IBR, 
see Sec.  171.7 of this subchapter). Until December 31, 2026, a 
cylinder may instead conform to ISO

[[Page 34621]]

9809-1:2010(E) (IBR, see Sec.  171.7 of this subchapter).
    (2) ISO 9809-2:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 2: 
Quenched and tempered steel cylinders and tubes with tensile strength 
greater than or equal to 1100 MPa (IBR, see Sec.  171.7 of this 
subchapter). Until December 31, 2026, a cylinder may instead conform to 
ISO 9809-2:2010 (IBR, see Sec.  171.7 of this subchapter).
    (3) ISO 9809-3:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 3: 
Normalized steel cylinders and tubes. (IBR, see Sec.  171.7 of this 
subchapter). Until December 31, 2026, a cylinder may instead conform to 
ISO 9809-3:2010(E) (IBR, see Sec.  171.7 of this subchapter).
    (4) ISO 9809-4:2014(E), Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction and testing--Part 4: Stainless 
steel cylinders with an Rm value of less than 1 100 MPa (IBR, see Sec.  
171.7 of this subchapter).
* * * * *
    (i) Design and construction requirements for UN non-refillable 
metal cylinders. In addition to the general requirements of this 
section, UN non-refillable metal cylinders must conform to ISO 
11118:2015(E) Gas cylinders--Non-refillable metallic gas cylinders--
Specification and test methods, in combination with ISO 11118:2015/Amd 
1:2019 Gas cylinders--Non-refillable metallic gas cylinders--
Specification and test methods--Amendment 1. (IBR, see Sec.  171.7 of 
this subchapter). Until December 31, 2026, the use of ISO 11118:2015 
(IBR, see Sec.  171.7 of this subchapter) without the supplemental 
amendment is authorized.
* * * * *
    (k) * * *
    (1) * * *
    (i) ISO 9809-1:2019(E) Gas cylinders--Refillable seamless steel gas 
cylinders--Design, construction, and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1100 MPa (IBR, 
see Sec.  171.7 of this subchapter). Until December 31, 2026, a 
cylinder may instead conform to ISO 9809-1:2010(E) (IBR, see Sec.  
171.7 of this subchapter).
    (ii) ISO 9809-3:2019(E) Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 3: 
Normalized steel cylinders and tubes. (IBR, see Sec.  171.7 of this 
subchapter). Until December 31, 2026, a cylinder may instead conform to 
ISO 9809-3:2010(E) (IBR, see Sec.  171.7 of this subchapter).
* * * * *
    (m) Design and construction requirements for UN metal hydride 
storage systems. In addition to the general requirements of this 
section, metal hydride storage systems must conform to ISO 
16111:2018(E) Transportable gas storage devices--Hydrogen absorbed in 
reversible metal hydride (IBR, see Sec.  171.7 of this subchapter). 
Until December 31, 2026, UN metal hydride storage systems may instead 
conform to ISO 16111:2008 (IBR, see Sec.  171.7 of this subchapter).
    (n) Design and construction requirements for UN cylinders for the 
transportation of adsorbed gases. In addition to the general 
requirements of this section, UN cylinders for the transportation of 
adsorbed gases must conform to the following ISO standards, as 
applicable:
    (1) ISO 11513:2019, Gas cylinders--Refillable welded steel 
cylinders containing materials for sub-atmospheric gas packaging 
(excluding acetylene)--Design, construction, testing, use and periodic 
inspection (IBR, see Sec.  171.7 of this subchapter). Until December 
31, 2026, UN cylinders may instead conform to ISO 11513:2011(E) (IBR, 
see Sec.  171.7 of this subchapter).
    (2) ISO 9809-1:2019(E): Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction, and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1100 MPa (IBR, 
see Sec.  171.7 of this subchapter). Until December 31, 2026, UN 
cylinders may instead conform to ISO 9809-1:2010(E) (IBR, see Sec.  
171.7 of this subchapter.
* * * * *
0
30. In Sec.  178.75, revise paragraph (d)(3) introductory text and 
paragraph (d)(3)(i) through (iii) to read as follows:

Sec.  178.75  Specifications for MEGCs.

* * * * *
    (d) * * *
    (3) Each pressure receptacle of a MEGC must be of the same design 
type, seamless steel, or composite, and constructed and tested 
according to one of the following ISO standards:
    (i) ISO 9809-1:2019(E), Gas cylinders--Refillable seamless steel 
gas cylinders--Design, construction, and testing--Part 1: Quenched and 
tempered steel cylinders with tensile strength less than 1100 MPa (IBR, 
see Sec.  171.7 of this subchapter). Until December 31, 2026, a 
pressure receptacle may instead conform to ISO 9809-1:2010(E) (IBR, see 
Sec.  171.7 of this subchapter).
    (ii) ISO 9809-2:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 2: 
Quenched and tempered steel cylinders and tubes with tensile strength 
greater than or equal to 1100 MPa (IBR, see Sec.  171.7 of this 
subchapter). Until December 31, 2026, a pressure receptacle may instead 
conform to ISO 9809-2:2010(E) (IBR, see Sec.  171.7 of this 
subchapter).
    (iii) ISO 9809-3:2019(E), Gas cylinders--Design, construction and 
testing of refillable seamless steel gas cylinders and tubes--Part 3: 
Normalized steel cylinders and tubes. (IBR, see Sec.  171.7 of this 
subchapter). Until December 31, 2026, pressure receptacle may instead 
conform to ISO 9809-3:2010(E) (IBR, see Sec.  171.7 of this 
subchapter).
* * * * *
0
31. In Sec.  178.609, revise paragraph (d)(2) to read as follows:

Sec.  178.609  Test requirements for packagings for infectious 
substances.

* * * * *
    (d) * * *
    (2) Where the samples are in the shape of a drum or jerrican, three 
samples must be dropped, one in each of the following orientations:
    (i) Diagonally on the top edge, with the center of gravity directly 
above the point of impact;
    (ii) Diagonally on the base edge; and
    (iii) Flat on the body or side.
* * * * *
0
32. In Sec.  178.706, revise paragraph (c)(3) to read as follows:

Sec.  178.706  Standards for rigid plastic IBCs.

* * * * *
    (c) * * *
    (3) No used material other than production residues or regrind from 
the same manufacturing process may be used in the manufacture of rigid 
plastic IBCs unless approved by the Associate Administrator.
* * * * *
0
33. In Sec.  178.707, revise paragraph (c)(3)(iii) to read as follows:

Sec.  178.707  Standards for composite IBCs.

* * * * *
    (c) * * *
    (3) * * *
    (iii) No used material, other than production residues or regrind 
from the same manufacturing process, may be used in the manufacture of 
inner receptacles unless approved by the Associate Administrator.
* * * * *

[[Page 34622]]

PART 180--CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS

0
34. The authority citation for part 180 continues to read as follows:

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

0
35. In Sec.  180.207, revise paragraphs (d)(3) and (5), and add 
paragraph (d)(8) to read as follows:

Sec.  180.207  Requirements for requalification of UN pressure 
receptacles.

* * * * *
    (d) * * *
    (3) Dissolved acetylene UN cylinders: Each dissolved acetylene 
cylinder must be requalified in accordance with ISO 10462:2013(E)/Amd 
1:2019 (IBR, see Sec.  171.7 of this subchapter). However, a cylinder 
may continue to be requalified in accordance with ISO 10462:2013(E) 
(IBR, see Sec.  171.7 of this subchapter) without the supplemental 
amendment until December 31, 2024. Further, a cylinder requalified in 
accordance with ISO 10462:2013(E) until December 31, 2018, may continue 
to be used until its next required requalification. The porous mass and 
the shell must be requalified no sooner than three (3) years, six (6) 
months, from the date of manufacture. Thereafter, subsequent 
requalifications of the porous mass and shell must be performed at 
least once every 10 years.
* * * * *
    (5) UN cylinders for adsorbed gases: Each UN cylinder for adsorbed 
gases must be inspected and tested in accordance with Sec.  173.302c of 
this subchapter and ISO 11513:2019(E) (IBR, see Sec.  171.7 of this 
subchapter). However, a UN cylinder may continue to be requalified in 
accordance with ISO 11513:2011(E) (IBR, see Sec.  171.7 of this 
subchapter) until December 31, 2024.
* * * * *
    (8) UN pressure drums: UN pressure drums must be inspected and 
tested in accordance with ISO 23088:2020 (IBR, see Sec.  171.7 of this 
subchapter).
* * * * *

     Issued in Washington, DC, on March 31, 2023, under authority 
delegated in 49 CFR 1.97.
William S. Schoonover,
Associate Administrator for Hazardous Materials Safety, Pipeline and 
Hazardous Materials Safety Administration.
[FR Doc. 2023-07109 Filed 5-26-23; 8:45 am]
 BILLING CODE 4910-60-P