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Biden-Harris Administration, U.S. Department of Transportation Announce Comprehensive Actions to Increase Underride Protection on Truck Trailers and Prevent Deadly Crashes

| Washington, DC

NHTSA issues final rule for rear underride protection, announces advisory committee on underride protection, and enacts critical safety mandates in the Bipartisan Infrastructure Law


The U.S. Department of Transportation’s National Highway Traffic Safety Administration today finalized a rule that updates two Federal Motor Vehicle Safety Standards to improve protection for drivers and passengers in light vehicles in the event of a rear underride crash. 

These crashes, which are often deadly, occur when the front end of a vehicle crashes into the back of a larger vehicle, such as a large trailer or semi-trailer, and slides under that vehicle. This rule, along with increased research and the creation of an advisory committee on underride protection is the result of President Biden’s Bipartisan Infrastructure Law and is a key part of USDOT’s 2022 National Roadway Safety Strategy.

“NHTSA’s priority is the safety of everyone on our roads,” said Dr. Steven Cliff, NHTSA’s Administrator. “This new rule will improve protection for passengers and drivers of passenger vehicles while also meeting a critical mandate from Congress under the Bipartisan Infrastructure Law.”

The rule requires rear impact guards on trailers and semi-trailers with sufficient strength and energy absorption to protect occupants of passenger vehicles in multiple crash scenarios  – helping to keep drivers safe and prevent deadly crashes. The final rule amends FMVSS No. 223, “Rear Impact Guards,” and FMVSS No. 224, “Rear Impact Protection.” 

In addition, NHTSA is implementing a number of other underride provisions of the Bipartisan Infrastructure Law, including: 

  • Establishing a Federal advisory committee on underride protection, which will complete research on side underride guards for trailers and semi-trailers to assess their effectiveness, feasibility, benefits, costs, and impact on intermodal operations.
  • Planning to publish an advance notice of proposed rulemaking to consider requirements for side underride guards for crashes into the sides of  trailers and semi-trailers. This rulemaking also responds to a provision in the Bipartisan Infrastructure Law to report the findings of research on side underride guards in a Federal Register notice to seek public comment.
  • Improving data collection of underride crashes by recommending inclusion of underride data in State crash data systems and by providing educational materials to State and local police departments on identifying and recording underride crashes; and
  • Conducting research on rear impact guard designs that better protect occupants of passenger vehicles in even more rear underride crash scenarios.

Please click here to learn more about the rulemaking process.

NHTSA 202-366-9550