Safety group says truck guard rails could prevent deaths

Tractor-trailers with side guard rails mounted between their tires are less likely to be involved in fatal crashes, an auto safety group says.

Federal law requires big trucks to have rear underride guards, which stop cars from traveling underneath the truck in an accident. But the government doesn't require side guards. The Insurance Institute for Highway Safety says side guards could prevent hundreds of traffic deaths per year.

The institute tested AngelWing, a steel rail covered with fiberglass that was mounted on a 53-foot trailer.

When a midsize car going 35 miles per hour hit the guard rail, the front crumpled but the car's air bags and seat belt protected the test dummy inside. In a test with no guard rails, the crash sheared off the car's roof.