Federal Motor Vehicle Safety Standards; Fuel System Integrity of Hydrogen Vehicles; Compressed Hydrogen Storage System Integrity; Incorporation by Reference

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>National Highway Traffic Safety Administration</SUBAGY> <CFR>49 CFR Part 571</CFR> <DEPDOC>[Docket No. NHTSA-2024-0090]</DEPDOC> <RIN>RIN 2127-AM40</RIN> <SUBJECT>Federal Motor Vehicle Safety Standards; Fuel System Integrity of Hydrogen Vehicles; Compressed Hydrogen Storage System Integrity; Incorporation by Reference</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> National Highway Traffic Safety Administration (NHTSA), Department of Transportation (DOT). <HD SOURCE="HED">ACTION:</HD> Final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> This final rule establishes two new Federal Motor Vehicle Safety Standards (FMVSS) specifying performance requirements for all motor vehicles that use hydrogen as a fuel source. The final rule is based on Global Technical Regulation (GTR) No. 13, Hydrogen and Fuel Cell Vehicles. FMVSS No. 307, “Fuel system integrity of hydrogen vehicles,” specifies requirements for the integrity of the fuel system in hydrogen vehicles during normal vehicle operations and after crashes. FMVSS No. 308, “Compressed hydrogen storage system integrity,” specifies requirements for the compressed hydrogen storage system to ensure the safe storage of hydrogen onboard vehicles. These two standards will reduce deaths and injuries from fires due to hydrogen fuel leakages and/or explosion of the hydrogen storage system. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> <E T="03">Effective date:</E> This final rule is effective July 16, 2025. <E T="03">IBR date:</E> The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register as of July 16, 2025. <E T="03">Compliance Dates:</E> The compliance date is September 1, 2028. <E T="03">Petitions for reconsideration:</E> Petitions for reconsideration of this final rule must be received no later than March 3, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Petitions for reconsideration of this final rule must refer to the docket and notice number set forth above and be submitted to the Administrator, National Highway Traffic Safety Administration, 1200 New Jersey Avenue SE, West Building, Washington, DC 20590. All petitions received will be posted without change to <E T="03">http://www.regulations.gov,</E> including any personal information provided. <E T="03">Privacy Act:</E> DOT will post any petition for reconsideration, and any other submission, without edit, to <E T="03">http://www.regulations.gov,</E> as described in the system of records notice, DOT/ALL-14 FDMS, accessible through <E T="03">https://www.transportation.gov/individuals/privacy/privacy-act-system-records-notices.</E> Anyone is able to search the electronic form of all submissions to any of our dockets by the name of the individual submitting the submission (or signing the comment, if submitted on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act Statement in the <E T="04">Federal Register</E> published on April 11, 2000 (Volume 65, Number 70; Pages 19477-78). <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> For technical issues, Ian MacIntire, General Engineer, Special Vehicles & Systems Division within the Division of Rulemaking, at (202) 493-0248 or <E T="03">Ian.MacIntire@dot.gov.</E> For legal issues, Paul Connet, Attorney-Advisor, NHTSA Office of Chief Counsel, at (202) 366-5547 or <E T="03">Paul.Connet@dot.gov</E> or Evita St. Andre, Attorney-Advisor, NHTSA Office of Chief Counsel, at (617) 494-2767 or <E T="03">Evita.St.Andre@dot.gov.</E> The mailing address of these officials is: National Highway Traffic Safety Administration, 1200 New Jersey Avenue SE, Washington, DC 20590. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. Executive Summary</FP> <FP SOURCE="FP-2">II. Background</FP> <FP SOURCE="FP-2">III. Summary of Comments</FP> <FP SOURCE="FP-2">IV. Response to Comments on Proposed Requirements</FP> <FP SOURCE="FP-2">V. Other Changes to the Regulatory Text</FP> <FP SOURCE="FP-2">VI. Rulemaking Analyses and Notices</FP> </EXTRACT> <HD SOURCE="HD1">I. Executive Summary</HD> Vehicle manufacturers have continued to seek out renewable and clean fuel sources as alternatives to gasoline and diesel. Compressed hydrogen has emerged as a promising potential alternative because hydrogen is an abundant element in the atmosphere and does not produce tailpipe greenhouse gas emissions when used as a motor fuel. However, hydrogen must be compressed to high pressures to be an efficient motor fuel and is also highly flammable, similar to other motor fuels. NHTSA has already set regulations ensuring the safe containment of other motor vehicle fuels such as gasoline in FMVSS No. 301, “Fuel system integrity,” and compressed natural gas (CNG) in FMVSS No. 304, “Compressed natural gas fuel container integrity,” and the fuel integrity systems of those fuels in FMVSS No. 301 and FMVSS No. 303, “Fuel system integrity of compressed natural gas vehicles,” respectively. No such standards currently exist in the United States covering vehicles that operate on hydrogen. Accordingly, this document establishes two new FMVSS to address safety concerns relating to the storage and use of hydrogen in motor vehicles, and to align the safety regulations of hydrogen vehicles with those of vehicles that operate using other fuel sources. NHTSA published the Notice of Proposed Rulemaking (NPRM) on April 17, 2024, seeking comments on the proposed standards. <SU>1</SU> <FTREF/> This final rule responds to and addresses the comments to the NPRM, reflecting input from stakeholders on various concerns and recommendations. The rule was developed in concert with efforts to harmonize hydrogen vehicle standards with international partners through the GTR process and harmonizes the FMVSS with GTR No. 13, Hydrogen and Fuel Cell Vehicles. <SU>2</SU> <FTREF/> <FTNT> <SU>1</SU>   <E T="03">See</E> 89 FR 27502 (Apr. 17, 2024), <E T="03">available at https://www.federalregister.gov/documents/2024/04/17/2024-07116/federal-motor-vehicle-safety-standards-fuel-system-integrity-of-hydrogen-vehicles-compressed.</E> </FTNT> <FTNT> <SU>2</SU>  A copy of GTR No. 13 as updated by the Phase 2 amendments is available at: <E T="03">https://unece.org/sites/default/files/2023-07/ECE-TRANS-180-Add.13-Amend1e.pdf</E> </FTNT> The two new FMVSS established by this document are: FMVSS No. 307, “Fuel system integrity of hydrogen vehicles,” and FMVSS No. 308, “Compressed hydrogen storage system integrity.” FMVSS No. 307 regulates the integrity of the fuel system in hydrogen vehicles during normal vehicle operations and after crashes. To this end, it includes performance requirements for the hydrogen fuel system to mitigate hazards associated with hydrogen leakage and discharge from the fuel system, as well as post-crash restrictions on hydrogen leakage, concentration in enclosed spaces, container displacement, and fire. FMVSS No. 308 regulates the compressed hydrogen storage system (CHSS) itself and primarily includes performance requirements that ensure the CHSS is unlikely to leak or burst during use, as well as requirements intended to ensure that hydrogen is safely expelled from the container when it is exposed to a fire. FMVSS No. 308 also specifies performance requirements for different closure devices in the CHSS. FMVSS No. 308 applies to all motor vehicles that use compressed hydrogen gas as a fuel source to propel the vehicle, regardless of the vehicle's gross vehicle weight rating (GVWR), except vehicles that are only equipped with cryo-compressed hydrogen storage systems or solid-state hydrogen storage systems to propel the vehicle. Portions of FMVSS No. 307 also apply to all motor vehicles that use compressed hydrogen gas as a fuel source to propel the vehicle, regardless of the vehicle's GVWR. However, while FMVSS No. 307's fuel system integrity requirements during normal vehicle operations apply to both light vehicles (vehicles with a GVWR of 4,536 kg or less) and to heavy vehicles (vehicles with a GVWR greater than 4,536 kg), FMVSS No. 307's post-crash fuel system integrity requirements apply only to compressed hydrogen-fueled light vehicles and to all <HD SOURCE="HD1">II. Background</HD> <HD SOURCE="HD2">A. Overview of GTR No. 13</HD> <HD SOURCE="HD3">1. The GTR Process</HD> The United States is a contracting party to the the Agreement concerning the Establishing of Global Technical Regulations for Wheeled Vehicles, Equipment and Parts which can be fitted and/or be used on Wheeled Vehicles (“1998 Agreement”). This agreement entered into force in 2000 and is administered by the United Nations Economic Commission for Europe's (UN ECE's) World Forum for the Harmonization of Vehicle Regulations (WP.29). The purpose of this agreement is to establish Global Technical Regulations (GTRs). At its 160th session in June 2013, UN ECE WP.29 formally adopted the proposal to establish GTR No. 13. NHTSA chaired the development of GTR No. 13 and voted in favor of establishing GTR No. 13. The Phase 2 updates to GTR No. 13 were adopted at the 190th Session of WP.29 on June 21, 2023. <SU>3</SU> <FTREF/> <FTNT> <SU>3</SU>   <E T="03">See https://unece.org/sites/default/files/2023-07/ECE-TRANS-180-Add.13-Amend1e.pdf.</E> </FTNT> As a Contracting Party Member to the 1998 Global Agreement that voted in favor of GTR No. 13 and the Phase 2 updates to GTR No. 13, NHTSA is obligated to initiate the process used in the U.S. to adopt Phase 2 GTR No. 13 as an agency regulation. This process was initiated by the NPRM published on April 17, 2024. NHTSA is not obligated to adopt the GTR, in whole or in part, after initiating this process. Additionally, NHTSA ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 552k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━