Side Underride Rulemaking Engagement a Necessity

Posted By: Brody Garland NATM News,

In April 2023, the National Highway Traffic Safety Administration (NHTSA) published an advance notice of proposed rulemaking (ANPRM) assessing the feasibility, benefits, costs, and other impacts of installing side underride guards on trailers and semitrailers. Underride crashes occur when the front end of a vehicle impacts a larger vehicle and slides under the chassis of the impacted vehicle. Side underride may occur in collisions in which a passenger vehicle crashes into the side of a large trailer or semitrailer because the trailer bed is higher than the hood of the passenger vehicle.

The ANPRM, which is in response to provisions in the November 2021 Bipartisan Infrastructure Law, directs the Secretary of Transportation to conduct research on side underride guards to better understand their overall effectiveness on vehicles with a gross vehicle weight rating of 10,000 pounds or more. 

NHTSA had initially initiated research on side underride guards following a March 2019 Government Accountability Office recommendation to conduct additional research on side underride guards to better understand their overall effectiveness and cost.

The research cited in the rulemaking as “Side Impact Guards for Combination Truck Trailers: Cost-Benefit Analysis”, provides a preliminary estimate that will inform any benefit-cost analysis that NHTSA would conduct if the agency were to propose a new Federal Motor Vehicle Safety Standard to require side underride guards on trailers and semi-trailers.

NHTSA analyzed crash data involving light passenger vehicles and tractor-trailers, and estimates that 17.2 lives would be saved and 69 serious injuries would be prevented annually when all trailers in the fleet are equipped with side underride guards.

The annual cost of equipping new trailers and semitrailers with side underride guards is estimated to range between $970 million and $1.2 billion. The resulting cost per equivalent life saved is in the range of $73.5 million to $103.7 million. 

The average total cost of installing side underride guards on a trailer, including hardware and labor, was estimated to be $2,990. The requirement for side underride guard would apply to 260,000 new trailers and semitrailers sold annually. Given these figures, the total annual initial cost for equipping all applicable new trailers with side underride guards would be approximately $778 million, resulting in total net benefits in the range of -$844 million to -$1,038 million.

In coordination with the rulemaking, NHTSA has also scheduled meetings for its Advisory Committee on Underride Protection (ACUP). The purpose of the ACUP is to provide advice and recommendations to the Secretary of Transportation on safety regulations to reduce underride crashes and fatalities relating to underride crashes.

Given the scope of the rulemaking, and the potential impacts to multiple industries, there will be a great deal of attention as the formal process proceeds. With multiple stakeholders pushing back on the validity, feasibility, and necessity for an updated side underride requirement expected during the public comment and ACUP committee process, engagement in the process will be essential as to whether NHTSA decides if these new standards are warranted.

Tractor-trailer with examples of rear and side underride guards. Graphic from United States Government Accountability Office, GAO-19-264
Tractor-trailer with examples of rear and side underride guards. Graphic from United States Government Accountability Office, GAO-19-264