Automatic occupant protection, state belt laws, and greater voluntary belt use amount to a ’winning combination’ that saves lives. Federal Motor Vehicle Safety Standard 208, as amended on July 17, 1984, combined a nationwide effort to increase belt use through state belt laws, enforcement and education, and a requirement that automatic occupant protection, such as air bags or automatic belts, be phased into passenger cars and light trucks. The effectiveness of automatic occupant protection is measured by statistical analysis of fatal crashes involving model year 1985—93 passenger cars, based on PARS data from 1986 through mid-1993.

Fatality risk of occupants in cars equipped with air bags plus manual belts (at 1993 use rates) is 23 percent lower than in "baseline" cars with manual belts at 1983 use rates. In similar comparisons, the fatality reductions for the four types of automatic belts range from 11 to 19 percent. All reductions are statistically significant. In the 1993 model—year mix of cars with air bags or automatic belts, at 1993 belt use rates, the average fatality risk is 20 percent lower than for baseline, manual—belt cars at 1983 use rates.