Semi-Trailer Side Underride Guards

What NHTSA is examining

The Office of Defects Investigation (ODI) received a petition from Eric Hein, Director of the Institute for Safer Trucking dated July 3, 2024, requesting an investigation of all van-type (also known as box) semi-trailers due to collisions with passenger vehicles and other vulnerable road users (pedestrians, bicyclists, or motorcyclists) resulting in significant injuries or death due to the lack of side underride guards (SUGs). On August 26, 2024, NHTSA opened Defect Petition DP24004 to evaluate the petitioner’s request. No trailer manufacturer or equipment supplier was identified as the specific subject of the petition. The petition itself can be reviewed at NHTSA.gov under ODI Number 11599188. Currently, a Federal Motor Vehicle Safety Standard (FMVSS) requiring side underride guards on semi-trailers does not exist. The petitioner contends that a failure to include side underride guards equates to a safety defect in the semi-trailer’s design, construction and performance. ODI was petitioned in 2021 for this same issue and, after evaluation, denied the request (DP21004). The petitioner here states that evidence of SUG effectiveness to prevent fatalities and mitigate serious injuries “has continued to accumulate” since the denial of DP21004. The petitioner also alleges that “[d]espite a high severity of risk resulting in frequent severe or fatal injuries from side underride crashes, NHTSA has taken no action to investigate recalling semi-trailers without SUGs.” Pursuant to the…

Vehicles under investigation