NHTSA extends review of side underride guard proposal

No news could be good news, at least for trailer manufacturers and trucking interests who question the cost/benefit math behind the most recent push for trailer side underride guards. According to the Sept. 4 update to the Unified Agenda of Federal Regulatory and Deregulatory Actions, the National Highway Traffic Safety Administration’s prerule status for the potential Side Underride Guards on Trailers and Semitrailers regulation remains in the “analyzing comments” stage, delaying further consideration until January 2026. The previous biannual update, from Fall 2024, listed last December as the target date.

NTSHA published an advance notice of proposed rulemaking (ANPRM) in April 2023, in response to a provision in the Bipartisan Infrastructure Law to conduct research on side underride guards to assess their effectiveness, feasibility, and costs and benefits. The public comment period on the ANPRM drew input from 2,000 individuals and organizations, revealing widely different opinions on NHTSA’s cost-benefit analysis.

The Truck Trailer Manufacturers Association (TTMA), which represents domestic and international manufacturers responsible for approximately 90% of the heavy-duty trailers manufactured for use in the U.S., consistently has stated that it would support the implementation of side underride guards “if they ever become both justified and technologically feasible.”

See also: Side underride notice triggers cost-benefit debate

Highway safety advocates, however, argued the NHTSA data vastly underestimated underride crashes, and used a majority position on the congressionally mandated Advisory Committee on Underride Protection (ACUP) to make the case that side underride guards are both necessary and cost effective, according to the committee’s June 2024 400-page  report to Congress.

The advice and recommendations of the committee called on NHTSA to withdraw its previously submitted ANPRM, or reissue a revised ANPRM and cost-benefit analysis that “acknowledges and accommodates critiques.” The report said NHTSA should require all semitrailers and single-unit trucks manufactured at 1998 to be equipped with side guards capable of preventing injurious passenger compartment intrusion. The report also recommended that NHTSA strengthen its rear impact guard regulations.

The committee meetings were contentious, however, with trucking interests contributing a “minority report” making the case that the official report recommendations reflect only the “preconceived views and biases of a slim majority” of committee members. That majority “voting bloc” pushed through a report that included “significant material” never considered by the ACUP while omitting items “that did not further the majority’s desired narrative.”

The minority report featured the November 2023 ACUP presentation from the American Trucking Associations that emphasized operational concerns such as the wide range of trailer configurations, several of which would be incompatible with side guards, as well as ground clearance challenges at railroad crossings and sloped loading ramps. Additionally, a May 2024 technical briefing by Utility Trailer CEO Jeff Bennett analyzed crash test evidence from commercially available side guards, including the manufacturer’s own units which it developed after discovering flaws in other systems.

Noting that Utility has provided 65 sets of guards to customers for a token $1 annual lease to facilitate real-world use and assessment, “No customer has asked for additional guards. In Utility Trailer’s view, it cannot give the guards away,” the report states.

The minority report calls for “comprehensive, evidence-based studies” to determine the scope of the underride problem, the ability to solve it, and the costs before adopting comprehensive underride-related regulations.