<div class="htmlview paragraph">In this paper, we describe some important aspects of crash severity sensing for “smart” airbag implementation. In particular, gray zone considerations are described in detail. Another important issue discussed is the loss of the additional front sensor used for crash severity sensing and its impact on system performance. A third issue of great importance is the second stage (assume a dual-stage inflator) firing delay. Finally, a discussion of some inherent problems with the crash severity sensor approach are discussed as well as dynamic range/resolution problems that accelerometers can encounter when used in the crush zone of a vehicle. A summary with conclusions and recommended approaches is presented.</div>