This project aimed to examine any change in helmet performance due to the amendment of the Australian Standard for bicycle helmets. Forty helmet sustaining impacts in crashes were collected from cyclists who were killed or treated at selected Melbourne hospitals during 1991-1992. These helmets were predominantly "foam-only" (a foam helmet often with a material cover), "micro-shell" (a foam helmet with a thin plastic shell), or light weight "hard-shell" (a foam helmet with a hard plastic shell) allowed under the amendment Standard. The new helmets were tested and information on the bicyclists' injuries obtained, so that comparison could be made with similar information previously obtained for older-design, heavier hard-shell helmets. It was concluded that the new helmets transmit a lower level of peak acceleration to the cyclist's head inside the helmet, for a given severity of impact on the external surface of the helmet. There was no evidence of a real difference in protective performance between the older and new helmets so far as actual head injury risks are concerned. This may have been due to the absence of a difference or due to the relatively small number of helmets considered in the two helmet groups. (A)
Abstract