In-depth accident analysis is a useful tool for investigating accident causes and effectiveness of injury prevention countermeasures. TNO Automotive is involved in an in-depth investigation of traffic accidents involving powered two-wheelers in The Netherlands. The question of this study is to extract indications for improving current helmet designs from result of this in-depth investigation. A thorough knowledge of the methodology of in-depth investigation is required for successful results. An in-depth analysis consists of a profound study of the accident circumstances, injuries of the involved and damage to the vehicles, followed by an accident reconstruction. In this study 95 cases are subjected to a general accident analysis. These cases consist of 39 motorcycle accidents, 46 moped accidents and 10 mofa accidents. Motorcyclists and moped drivers are forced by law to wear helmet. However, over 8 Fourteen cases were subjected to an in-depth accident analysis. From the accident reconstructions an average impact velocity of 38.5 km/h was determined. Most frequently the driver of the powered two-wheeler collided frontally into an other involved vehicle. The helmet damage increases with increasing impact velocity, while the head injury severity does not. Probably, because of the relatively low impact velocities. Thus, the helmets have proven their effectiveness, although no quantitative relation for helmet effectiveness was found.In the near future, more cases will be completed, giving access to an increasing amount of data. Hopefully, these will contain enough information for improving the current helmet designs. To increase the possibility of success, the in-depth accident analysis could be extended with a closer investigation of the helmets. Especially, by determining the material type of the helmet outer shell and measuring the residual foam deformation. (Author/publisher)
Abstract