Automatic safety belt use in Michigan: A two-year follow-up

The use of automatic safety belts among motorists throughout the state of Michigan was examined as part of a broader direct observation survey to measure compliance with the state's mandatory belt use law. Use of the most common types of automatic belt systems were measured: the nonmotorized detachable three-point lap and shoulder belt system, and the two-belt system with either a motorized shoulder belt and manual lap belt or a nonmotorized shoulder belt and manual lap belt. Belt use rates in vehicles with and without air bags were also compared. A total of 1,367 drivers and front-right passengers were observed with automatic belt systems between June 1 and July 11, 1992. Use of nonmotorized detachable three-point lap and shoulder belt systems was 72.3%. Lap belt use of motorized shoulder and manual lap belt systems was 70.5%. Lap belt use of nonmotorized shoulder and manual lap belt systems was 60.2%. Of all motorized and nonmotorized shoulder belt and manual lap belt systems observed, 94.5% had the shoulder belts connected.