In order to better isolate the causative influence of mass (as distinct from other factors such as size) on driver risk in two-car crashes, Newtonian Mechanics is used to establish that when two-cars crash head-on into each other, the ratio of their changes in speed (delta-V) is inversely proportional to the ratio of their masses. Using National Accident Sampling System data, the probability of a driver fatality is determined as a function of delta-V. Combining these two effects, the risk of death in the lighter car divided by the risk of death in the heavier car (the "fatality risk ratio") is calculated as a function of the mass of the heavier car divided by the mass of the lighter car (the "mass ratio"). Parallel analyses are performed for severe injuries. (AIS more than 3), and for belted drivers as well as drivers irrespective of belt use. The calculated relationship between fatality risk ratio and mass ratio are of the same form as those determined in an earlier study using actual fatality data. Discussions by Chipman, M.L. and Nash, C.E. are also presented. (A)
Samenvatting