Federal Motor Vehicle Safety Standards; Rear Impact Guards

In 1996, the agency established standards for underride guards for trailers and semitrailers in order to reduce the risk to passenger vehicle occupants in crashes in which a passenger vehicle impacts the rear end of a trailer or semitrailer. In establishing these standards, the agency recognized that compliance with the requirements was not practicable for a small number of vehicles due to the presence of work- performing equipment mounted on the rear of a trailer or semitrailer. These vehicles are designated as "special purpose vehicles" and are excluded from the standard. Today's final rule amends the definition of "special purpose vehicle" by adding a precise description of the cubic area in which work-performing equipment must reside in or move through while a trailer is moving. We have also determined that the addition of those specifications eliminates the need to exclude expressly vehicles equipped with specific liftgate designs. Finally, we are amending the requirements regarding the location of the rearmost surface of an impact guard as proposed.