Safety padding performances to protect from severe head injuries during alpine skiing

To protect skiers from the collisions with obstacles (CWOs), ski areas place padding on these obstacles. Padding behavior was previously experimentally investigated for few specific head impact conditions. The goal of this study is to numerically evaluate padding ability to reduce head injury risks in multiple scenarios of CWOs. A multibody model of a skier colliding with an obstacle was associated with a padding model, calibrated based on experimental tests. Different obstacle protections (unprotected, 15-, 20-, 30-cm thick padding), skier speeds, obstacle shapes and distances were investigated to model 3692 scenarios of CWOs. Head injury risks were evaluated based on HIC15 and maximal linear accelerations (Amax). Kruskal-Wallis tests were used to investigate the injury risks regarding the initial conditions, impact conditions and obstacle protection. These simulations resulted in high head impact speeds (30.4 +/- 14.2 km/h). The padding modeled significantly reduced Amax (368 +/- 275 g unprotected VS 215 +/- 240 g with 15-cm thick padding) and severe injury risks (p < 0.001). For low head impact speeds (<20 km/h), all pads were able to protect from severe injuries, whereas for moderate impact speeds (<40 km/h), the 30-cm thick padding offered better protection from severe injuries. However, even thick padding could not protect the skier model from high-speed impacts (>40 km/h). This study evaluated padding performances in various accident conditions and brought quantitative information for field evolutions regarding padding protection. These results constitute useful information to improve the padding standard and to design more efficient padding.