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The Importance of Side Underride Protection

Blog Post

Rear underride protection for trailers was initially put in place by the Interstate Commerce Commission in the 1960s. Over the years, the regulations have been modified to increase the size and strength of these devices. The 2021 Infrastructure Investment and Jobs Act directed the Department of Transportation (DOT) to research side underride guards to better understand their effectiveness, feasibility, benefits, costs, and impacts of installing them on trailers and semitrailers.

The Research and Regulatory Process

A 16-member committee has been tasked with developing recommendations for potential regulatory changes. The committee includes representatives from underride crash victims, truck safety organizations, crash investigators, law enforcement, motor carriers, truck and trailer manufacturers, the insurance industry, and motor vehicle engineers.

Industry Concerns

While side underride protection is required in Europe, U.S. trailer manufacturers have not seen demand for this optional feature. Side skirts used by some motor carriers improve fuel economy but are not crash-resistant. The motor carrier industry has raised concerns about the financial cost and the decrease in hauling capacity due to the added weight, estimated at up to 1,000 pounds. Additionally, there are engineering challenges in designing these systems for different types of trailers without impeding loading/unloading or interfering with docking configurations.

Cost and Safety Analysis

The National Highway Traffic Safety Administration (NHTSA) reported that equipping all large trucks in the U.S. fleet would cost between $973 million and $1.2 billion and would prevent 17 fatalities and 69 serious injuries per year. The Insurance Institute for Highway Safety (IIHS) argues that this is understated and believes that significantly more lives could be saved. NHTSA’s analysis excluded many types of crashes that are likely relevant, such as those involving multiple vehicles, speeds greater than 40 mph, and crashes involving pedestrians, bicyclists, and motorcyclists.

Committee Recommendations and Next Steps

During the last committee meeting, a motion was approved calling on NHTSA to disseminate educational material to law enforcement to help identify and record underride crashes. Additionally, the committee recommended including a checkbox for underride crashes on accident investigation forms, which would require jurisdictions to alter their crash reports and provide related training.

The committee also voted to recommend that NHTSA proceed with the rulemaking process to require side underride protection. The chairman, Lee Jackson, will write the majority report, while Jeff Bennett from Utility Trailer Manufacturing will write the minority report. NHTSA will publish an Advanced Notice of Rulemaking, initiating a comment period and providing the first look at the actual requirements. The entire process will likely take a year or more before any new regulations are published.