Because there is some apprehension about the possibility of injury occurring if the surface of an inflating air bag were to strike the face or eye of passengers in an automobile collision, an experiment was devised to test the results of such an impact. In evaluating injury, three mechanical factors were considered: inflation velocity; bag maximum internal pressure; and impulse at bag impact. A total of 37 rabbits, with eyelids sutured open, were placed in a wooden box. In order to find the impulse on the rabbit's eye, an impulse measurement device (an eye model constructed of polyvinyl chloride) was used to serve as a cornea at the instant of impact. Permissible safety thresholds were derived on the basis of the experimental results. The reported time required for a human eye to blink is 28-217 milliseconds. Since the inflation time of commercial air bags is 25-35 milliseconds, it is entirely conceivable that eye injury can occur. Even though it was demonstrated that the air bag does constitute a source of danger to eye and facial skin, it is not recommended that air bag development and application be arrested.
Abstract