June 12, 2000
While the use of automatic shoulder belts with lap belts reduces the risk of death in crashes by up to 86 percent, the protection afforded by a shoulder belt alone is significantly weaker. Use of automatic belts without lap belts is also associated with an increased risk of serious chest and abdominal injury.
More than 27 million vehicles have been manufactured with automatic two-point belt systems since 1987. Various studies have shown that drivers in these vehicles don't use their manual lap belts between 50 and 71 percent of the time.
Seat belts, when properly used, make a dramatic difference in reducing the injuries and death caused by car crashes. Unfortunately, the safety margin is drastically reduced--and often entirely lost--when a driver or passenger rides with an automatic shoulder belt and an unclasped lap belt.