Crash testing has revealed dynamic problems with present designs for air bag passive restraints which must be resolved. Out-of-position occupants can restrict deployment of the air bag or affect its restraint action. In rollover and side impact accidents, today's air bag offers only minimal restraint. Accordingly, it appears essential to use the lap belt, in combination with air bags, to achieve an improved restraint system over current systems when usage rates and effectiveness are considered. The noise level created by air bag actuation may exceed tolerance levels in some humans. Inadvertent deployment of air bags could compromise the driver's control of the vehicle. These and other technical problems must be resolved before such systems are furnished in automobiles to be sold to the public.