General Motors Corp. on April 28 announced results of an independent study concluding that GM customers have avoided more than 17,000 vehicle crashes -- representing more than a 5 percent reduction in daytime, multi-vehicle, non-rear-end collisions -- since GM began equipping vehicles with daytime running lamps in 1995. As the name suggests, this safety feature increases a vehicle's visibility by illuminating lamps on the front of the vehicle whenever the headlamps are not turned on. Using data from Scandinavian countries where daytime running lamps were mandatory, GM petitioned the National Highway Traffic Safety Administration in 1990 to allow automakers to install the feature voluntarily. Once NHTSA allowed daytime running lamps in 1993, GM began installing them. By the 1997 model year, all GM cars and trucks sold in the United States had daytime running lamps. To date, GM has sold more than 20 million vehicles in the United States equipped with daytime running lamps as standard equipment. The study, conducted by Exponent Failure Analysis Associates of San Francisco, compared the collision rates of specific GM, Volvo, Saab and Volkswagen vehicles before and immediately after the introduction of daytime running lamps. Using information from police accident reports and R. L. Polk registration data from 12 states, the study concluded that the reduction of relevant crashes was in excess of 5 percent, and the reduction in urban vehicle-to-pedestrian crashes was approximately 9 percent.