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Final Rule

Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems for Light Vehicles

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What is this Federal Register notice?

This is a final rule published in the Federal Register by Transportation Department, National Highway Traffic Safety Administration. Final rules have completed the public comment process and establish legally binding requirements.

Is this rule final?

Yes. This rule has been finalized. It has completed the notice-and-comment process required under the Administrative Procedure Act.

Who does this apply to?

Consult the full text of this document for specific applicability provisions. The affected parties depend on the regulatory scope defined within.

When does it take effect?

This document has been effective since July 8, 2024.

Why it matters: This final rule amends regulations in multiple CFR parts.

📋 Related Rulemaking

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Regulatory History — 4 documents in this rulemaking

  1. May 9, 2024 2024-09054 Final Rule
    Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems f...
  2. Nov 26, 2024 2024-27349 Final Rule
    Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems f...
  3. Dec 11, 2024 2024-28998 Final Rule
    Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems f...
  4. Jan 27, 2025 2025-01832 Final Rule
    Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems f...

Document Details

Document Number2024-09054
TypeFinal Rule
PublishedMay 9, 2024
Effective DateJul 8, 2024
RIN2127-AM37
Docket IDDocket No. NHTSA-2023-0021
Text FetchedYes

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Related Documents (by RIN/Docket)

Doc #TypeTitlePublished
2025-01832 Final Rule Federal Motor Vehicle Safety Standards; ... Jan 27, 2025
2024-28998 Final Rule Federal Motor Vehicle Safety Standards; ... Dec 11, 2024
2024-27349 Final Rule Federal Motor Vehicle Safety Standards; ... Nov 26, 2024

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Full Document Text (98,239 words · ~492 min read)

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<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>National Highway Traffic Safety Administration</SUBAGY> <CFR>49 CFR Parts 571, 595, and 596</CFR> <DEPDOC>[Docket No. NHTSA-2023-0021]</DEPDOC> <RIN>RIN 2127-AM37</RIN> <SUBJECT>Federal Motor Vehicle Safety Standards; Automatic Emergency Braking Systems for Light Vehicles</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 adopts a new Federal Motor Vehicle Safety Standard to require automatic emergency braking (AEB), including pedestrian AEB (PAEB), systems on light vehicles. An AEB system uses various sensor technologies and sub-systems that work together to detect when the vehicle is in a crash imminent situation, to automatically apply the vehicle brakes if the driver has not done so, or to apply more braking force to supplement the driver's braking. This final rule specifies that an AEB system must detect and react to an imminent crash with both a lead vehicle or a pedestrian. This final rule fulfills a mandate under the Bipartisan Infrastructure Law (BIL) directing the Department to promulgate a rule to require that all passenger vehicles be equipped with an AEB system. The purpose of this final rule is to reduce the number of deaths and injuries that result from crashes in which drivers do not apply the brakes or fail to apply sufficient braking power to avoid or mitigate a crash, and to reduce the consequences of such crashes. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> <E T="03">Effective Date:</E> This rule is effective July 8, 2024. <E T="03">IBR date:</E> The incorporation by reference of certain material listed in the rule is approved by the Director of the <E T="04">Federal Register</E> beginning July 8, 2024. The incorporation by reference of certain other material listed in the rule was approved by the Director of the Federal Register as of July 8, 2022. <E T="03">Compliance Date:</E> September 1, 2029. However, vehicles produced by small-volume manufacturers, final-stage manufacturers, and alterers must be equipped with a compliant AEB system by September 1, 2030. <E T="03">Petitions for reconsideration:</E> Petitions for reconsideration of this final rule must be received not later than June 24, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Petitions for reconsideration of this final rule must refer to the docket number set forth above (NHTSA-2023-0021) and be submitted to the Administrator, National Highway Traffic Safety Administration, 1200 New Jersey Avenue SE, Washington, DC 20590. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> <E T="03">For technical issues:</E> Mr. Markus Price, Office of Crash Avoidance Rulemaking, Telephone: 202-366-1810, Facsimile: 202-366-7002. <E T="03">For legal issues:</E> Ms. Sara R. Bennett, Office of the Chief Counsel, Telephone: 202-366-2992, Facsimile: 202-366-3820. The mailing address for these officials is: National Highway Traffic Safety Administration, 1200 New Jersey Avenue SE, Washington, DC 20590. </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> This final rule adopts a new Federal Motor Vehicle Safety Standard (FMVSS) No. 127 to require automatic emergency braking (AEB), including pedestrian AEB (PAEB), systems on light vehicles. FMVSS No. 127 applies to all passenger cars and to all multipurpose passenger vehicles (MPVs), trucks, and buses with a gross vehicle weight rating (GVWR) of 4,536 kilograms (kg) (10,000 pounds (lbs.)) or less (“light vehicles”). An AEB system uses various sensor technologies and sub-systems that work together to detect when the vehicle is in a crash imminent situation, to automatically apply the vehicle brakes if the driver has not done so, or to apply more braking force to supplement the driver's braking. This final rule specifies that an AEB system must detect and react to an imminent crash with both a lead vehicle and a pedestrian. This final rule advances DOT's January 2022 National Roadway Safety Strategy, which identified a requirement for AEB, including PAEB technologies, on new passenger vehicles as a key Departmental action to improve vehicle and pedestrian safety. Finally, this final rule fulfills section 24208(a) of BIL, which directs the Secretary of Transportation to promulgate a rule to require that all passenger vehicles be equipped with an AEB system. NHTSA published the notice of proposed rulemaking preceding this final rule on June 13, 2023 (88 FR 38632). <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="FP1-2">A. The Safety Problem</FP> <FP SOURCE="FP1-2">B. Bipartisan Infrastructure Law (BIL)</FP> <FP SOURCE="FP1-2">C. High-level Summary of Comments on the NPRM</FP> <FP SOURCE="FP1-2">D. Summary of the Notice of Proposed Rulemaking</FP> <FP SOURCE="FP1-2">E. Additional Research Conducted in 2023</FP> <FP SOURCE="FP-2">III. Final Rule and Response to Comments</FP> <FP SOURCE="FP1-2">A. Summary of the Final Rule (and Modifications to the NPRM)</FP> <FP SOURCE="FP1-2">B. Application </FP> <FP SOURCE="FP1-2">C. Definitions</FP> <FP SOURCE="FP1-2">D. FCW and AEB Equipment Requirements</FP> <FP SOURCE="FP1-2">1. Minimum Activation Speed</FP> <FP SOURCE="FP1-2">2. Maximum Activation Speed</FP> <FP SOURCE="FP1-2">3. Environmental Conditions</FP> <FP SOURCE="FP1-2">E. AEB System Requirements (Applies to Lead Vehicle and Pedestrian)</FP> <FP SOURCE="FP1-2">1. Forward Collision Warning Requirements</FP> <FP SOURCE="FP1-2">a. FCW Signal Modality</FP> <FP SOURCE="FP1-2">b. FCW Auditory Signal Requirements</FP> <FP SOURCE="FP1-2">c. FCW Auditory Signal Presentation with Simultaneous Muting of Other In-Vehicle Audio</FP> <FP SOURCE="FP1-2">d. FCW Visual Symbol Requirements</FP> <FP SOURCE="FP1-2">e. FCW Visual Signal Location Requirements</FP> <FP SOURCE="FP1-2">2. AEB Requirement</FP> <FP SOURCE="FP1-2">a. AEB Deactivation</FP> <FP SOURCE="FP1-2">b. Aftermarket Modifications</FP> <FP SOURCE="FP1-2">c. No-Contact Requirement for Lead Vehicle AEB</FP> <FP SOURCE="FP1-2">d. No-Contact Requirement for Pedestrians</FP> <FP SOURCE="FP1-2">e. Permissibility of Failure</FP> <FP SOURCE="FP1-2">F. False Activation Requirement</FP> <FP SOURCE="FP1-2">1. Need for Requirement</FP> <FP SOURCE="FP1-2">2. Peak Additional Deceleration</FP> <FP SOURCE="FP1-2">3. Process Standard Documentation as Alternative to False Activation Requirements</FP> <FP SOURCE="FP1-2">4. Data Storage Requirement as Alternative to False Activation Requirements</FP> <FP SOURCE="FP1-2">G. Malfunction Detection Requirement</FP> <FP SOURCE="FP1-2">1. Need for Requirement</FP> <FP SOURCE="FP1-2">2. Malfunction Telltale</FP> <FP SOURCE="FP1-2">3. Sensor Obstructions and Testing</FP> <FP SOURCE="FP1-2">H. Procedure for Testing Lead Vehicle AEB</FP> <FP SOURCE="FP1-2">1. Scenarios</FP> <FP SOURCE="FP1-2">2. Subject Vehicle Speed Ranges</FP> <FP SOURCE="FP1-2">3. Headway</FP> <FP SOURCE="FP1-2">4. Lead Vehicle Deceleration</FP> <FP SOURCE="FP1-2">5. Manual Brake Application</FP> <FP SOURCE="FP1-2">6. Testing Setup and Completion</FP> <FP SOURCE="FP1-2">7. Miscellaneous Comments</FP> <FP SOURCE="FP1-2">I. Procedures for Testing PAEB</FP> <FP SOURCE="FP1-2">1. Scenarios</FP> <FP SOURCE="FP1-2">2. Subject Vehicle Speed Ranges</FP> <FP SOURCE="FP1-2">3. Pedestrian Test Device Speed</FP> <FP SOURCE="FP1-2">4. Overlap</FP> <FP SOURCE="FP1-2">5. Light Conditions</FP> <FP SOURCE="FP1-2">6. Testing Setup</FP> <FP SOURCE="FP1-2">J. Procedures for Testing False Activation</FP> <FP SOURCE="FP1-2">K. Track Testing Conditions</FP> <FP SOURCE="FP1-2">1. Environmental Test Conditions</FP> <FP SOURCE="FP1-2">2. Road/Test Track Conditions</FP> <FP SOURCE="FP1-2">L. Vehicle Test Device</FP> <FP SOURCE="FP1-2">1. General Description</FP> <FP SOURCE="FP1-2">2. Definitions</FP> <FP SOURCE="FP1-2">3. Sideview Specification</FP> <FP SOURCE="FP1-2">4. Field Verification Procedure</FP> <FP SOURCE="FP1-2">5. Dimensional Specification</FP> <FP SOURCE="FP1-2">6. Visual and Near Infrared Specification</FP> <FP SOURCE="FP1-2">7. Radar Reflectivity</FP> <FP SOURCE="FP1-2">8. List of Actual Vehicles</FP> <FP SOURCE="FP1-2">M. Pedestrian Test Devices</FP> <FP SOURCE="FP1-2">1. General Description</FP> <FP SOURCE="FP1-2">2. Dimensions and Posture</FP> <FP SOURCE="FP1-2">3. Visual Properties</FP> <FP SOURCE="FP1-2"> 4. Radar Properties </FP> <FP SOURCE="FP1-2">5. Articulation Properties</FP> <FP SOURCE="FP1-2">6. Comments on Thermal Characteristics</FP> <FP SOURCE="FP1-2">N. Miscellaneous Topics</FP> <FP SOURCE="FP1-2">O. Effective Date and Phase-In Schedule</FP> <FP SOURCE="FP-2">IV. Summary of Estimated Effectiveness, Cost, and Benefits</FP> <FP SOURCE="FP1-2">A. Benefits</FP> <FP SOURCE="FP1-2">B. Costs</FP> <FP SOURCE="FP1-2">C. Net Impact</FP> <FP SOURCE="FP-2">V. Regulatory Notices and Analyses</FP> <FP SOURCE="FP-2">VI. Appendices to the Preamble</FP> <FP SOURCE="FP1-2">A. Appendix A: Description of the Lead Vehicle AEB Test Procedures</FP> <FP SOURCE="FP1-2">B. Appendix B: Description of the PAEB Test Procedures</FP> <FP SOURCE="FP1-2">C. Appendix C: Description of the False Activation Test Procedures</FP> </EXTRACT> <HD SOURCE="HD1">I. Executive Summary</HD> In 2019, prior to the COVID-19 pandemic, there were nearly 2.2 million rear-end police-reported crashes involving light vehicles, which led to 1,798 deaths and 574,000 injuries. In addition, there were 6,272 pedestrian fatalities in motor vehicle crashes, representing 17 percent of all motor vehicle fatalities. <SU>1</SU> <FTREF/> This represents the continuation of the recent trend of increased pedestri ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 658k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
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