Abstract
The effectiveness of airbags was determined by assuming that they did not affect ejection probability, and protected only in frontal, and near- frontal, crashes; the impact- reducing effectiveness in such crashes was assumed equal to that of lap /shoulder belts. The effectiveness, estimated as 18%, thus depends on the distribution of crashes by direction of impact, and the incidence of ejection. It is concluded that effectiveness does not depend much on driver age or alcohol consumption, but is greater for two- car crashes than for single- car crashes (21% compared to 16%).