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Understanding Rear Impact Guards

Rear impact guards are an important safety feature on any trailer. In this post we will share their history and current regulations to keep in mind.



What are Rear Impact Guards?

Historically known by a few names such as bumpers, Interstate Commerce Commission or “ICC” bumpers, Rear Underride Guards, and Rear Impact Guards; this structure on the rear of a trailer has the primary purpose of preventing or reducing serious injury to automobile passengers during rear impact and/or an underride collision with a trailer.


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A Sad History

These were originally implemented after the tragic death of Hollywood star Jayne Mansfield in 1967, who tragically died enroute to a television appearance, when her car crashed under the rear of a truck trailer. 

Shortly after the 'Mansfield accident', the U.S. National Highway Traffic Safety Administration (NHTSA) proposed new standards calling for the addition of u
nderride protection on the rear of some truck trailers to help prevent deaths due to the underride of passenger cars.

As of July 2022, NHTSA announced new rules for upgrading the Federal Vehicle Safety Standards (FMVSS) to include rear impact guards by 2024. Luckily, 94% of all trailers built in North America today exceed the new NHTSA requirements.


What you need to know

Current regulations specify that the Rear Underride Guards on your trailers must meet the standards in effect at the time of the trailer’s original manufacturing. This means that older trailers are “grandfathered in” and do not require replacement. However, the regulations do require that rear impact guards be kept in good condition and properly repaired or replaced in keeping with the original standards. If you need to repair or replace, consider the following:

  • The American Trucking Associations Technology and Maintenance Council (TMC) has updated repair guidelines that conform to FMVSS standards. 
  • If a rear underride guard is ever compromised in a way that affects its ability to function properly, call the lessor for guidance on how to proceed.

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At Premier Trailer Leasing, we strive to make your day better, whether that’s through supporting our customers with our national branch network, our large growing fleet and flexible approach to leasing, or by sharing our experience and expertise. Give us a call if you'd like to discuss other ways, we can be a resource for you.




trevorIndustry veteran Trevor Ternes has spent the 27 years of his career exclusively in trailer rental and leasing, with a specialty in Operations and Operations Management. Trevor enjoys learning and sharing industry knowledge with customers and Premier team members alike and is always glad to help answer questions. 


Trevor Ternes 







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