At this time, a consensus does not exist regarding the number and types of crash tests which need to be conducted to establish a basis for crash sensor threshold behavior. Experience obtained from the 1973-1976 General Motors air bag equipped cars (1-3), the Police Fleet Retrofit Driver Air Bag Program (4), and the Ford Tempo GSA Project (5), are reviewed and results from these projects, and from tests conducted by and for the automotive industry, are discussed. Such sensor threshold tests could be conducted as part of the design of an air bag system.