Today's cars do not sufficiently prevent neck injuries in rear end impacts. So called whiplash injuries are often sustained at low velocities. According to Swedish road casualty statistics, the risk for whiplash injuries increases dramatically with the velocity change of the impacted car in the interval between 10-20 km/h. During recent years, much progress has been made in research concerning this issue. This includes new findings from injury statistics, better knowledge of injury mechanisms (even if they are not yet fully understood) and development of suitable rear impact dummies. This paper describes a new sled test procedure involving two levels of rear impact severity. In the proposed procedure, a new neck injury criterion (NIC) which is a measure of the effect of violence to the neck, is used to evaluate the level of neck protection. Seats, from two cars with different neck injury-risk rating (according to Swedish statistics), have been tested according to the new procedure and compared with a new seat concept. The results indicate that a seat back with a low yielding limit has a lower risk of neck injury, which is reflected in lower NIC-values. (A)
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