For the past 20 years or so, performance requirements intended to protect motor vehicle occupants against head injury have invariably been based on the use of the Head Injury Criterion (HIC). The most evident difficulty with the Criterion is simply that the assumed inverse relationship between the tolerable level of head acceleration and its duration leads to predictions that contradict practical experiences. Extensive data from tests by Transport Canada and other agencies are presented which show that, regardless of either the time duration of the calculation or the criterion level, HIC is incapable of distinguishing potentially injurious events from those that are known to be harmless. For the protection of motor vehicle occupants in frontal collisions, the same data show that an 80 g limit on Anthropometric Test Dummy (ATD) head acceleration constitute a rational, attainable and effective performance requirement.
Samenvatting