An underride accident occurs when a portion of a passenger car collides with and slides underneath the truck. These types of accidents can be particularly deadly, as it is possible that the passenger vehicle’s roof can be sliced off entirely.
Some trucks are equipped with “underride guards” intended to reduce the risk of serious injuries or deaths in a truck crash. However, a 2011 study by the Insurance Institute for Highway Safety (IIHS) found that existing underride guards can fail in tractor-trailer crashes, even at relatively low speeds. The agency has asked the federal government for stronger rear guards and is recommending that underride guards be mandated for more commercial motor vehicles.