ROADSIDE SAFETY HARDWARE CRASH TEST PROCEDURES IN THE UNITED STATES

The development of NCHRP Report 350, which gives recommended procedures for the safety performance evaluation of highway features, is described. The summary of Report 350 is provided as an explanation of the content. The approach chosen in the report is to test for severe impact conditions, the area where most separation among different types of barriers is likely to occur. The Report also indicates that additional impact testing may be necessary for conditions other than those it is intended for. A minimum matrix of passenger vehicle tests, supplemented by heavy vehicle tests, is outlined. Test matrixes are given for longitudinal barriers, breakaway features, crash cushions and end treatments. Impact conditions and impact angle are described. The performance valuation criteria are structural adequacy, occupant risk and vehicle trajectories. The merits of the flail space model and the acceleration severity index for predicting the effectiveness of crash cushions are discussed. For the covering abstract see ITRD E123354.