IMPULSE FORCE AS AN ADDITIONAL SAFETY CRITERION FOR IMPROVING THE INJURY PREVENTION PERFORMANCE OF IMPACT ATTENUATION SURFACES IN CHILDREN'S PLAYGROUNDS

摘要

More than four decades has passed since introducing safety standards for Impact Attenuation Surfacing (IAS) used in children's playgrounds. Falls in children's playgrounds is a major source of injuries and IAS is one of the best safety interventions deployed to reduce the incidence and severity of these injuries. Currently there are two criteria that measure the injury prevention performance of IAS, namely: Head Injury Criteria (HIC); and maximum acceleration (G_(max)). Based on the ASTM playground safety standard F1292 the thresholds of HIC and G_(max) are 1000 and 200g respectively. If the playground IAS complies with this Standard the number and severity of fall-related injuries in playgrounds should be decreased. However after implementing these standards a high number of children continue to be hospitalized due to fall-related playground injuries In this paper we tested ten samples based on ASTM F1292 standard to propose the introduction of an additional criterion to HIC and G_(max) which can filter and remove hazardous IAS that technically comply with the current 1000 HIC and 200g safety thresholds. The proposed criterion is called the impulse force criterion (I_f) and combines the change of the momentum and the impact duration. The G_(max), HIC and I_f results are presented graphically and numerically.