Abstract
An aging process of the webbing due to mechanical and climatic influences may occur during service life of safety belts. Tests were conducted on 65 used belts removed from vehicles with a maximum of 250 000 km driving distance to determine the effect of aging on the effectiveness of the belts. In dynamic tests simulating a car crash it was found that especially abrasion of the strap leads to a drop in strength. However, within the normal service life of a motor car, the quality of safety belts is not affected.