This study aims at determining, with the maximum precision, the performance of the 3 point safety belt in different accident configurations, and more particularly in frontal collisions. For this purpose, two matched samples were taken from a file of 3000 accidents, analysed by a multidisciplinary study group. These samples of 100 front seat occupants wearing seat belts, and 100 not wearing seat belts were made up in such a manner that, for every belted occupant, corresponds an occupant not wearing a belt, the one and the other being in equivalent circumstances, using the following factors: (1) make and type of the vehicle, (2) seat occupied, (3) age (as far as possible), (4) direction of impact, (5) violence of the impact (same class of delta v and mean gamma), (6) possible intrusion of passenger compartment, (7) possible overload caused by a rear seat occupant. Using this method of comparison, the report shows the effectiveness of the 3 point belt and explains the variations of effectiveness that appear in normal case studies.
Abstract