Safety of sidefacing truck occupants in a frontal collision

In many large truck cabins the area behind the driver and passenger seats is used as living quarters. In addition to sleeping accomodation, the area may be supplied with an office package including a table and benches along the side walls of the cabin. People occupying these benches are sitting laterally to the direction of travel. During a frontal collision of the truck, these sidefacing occupants are subject to lateral loading. In order to minimise injury, an appropriate and dedicated restraint system has to be developed, as conventional systems are merely designed for frontal collisions. The safety problem of sidefacing occupants has been recognised in army transport, aviation and light people movers. As yet, a satisfactory solution has not been presented, but the numbers of people participating in traffic in sidefacing positions are still increasing. An extensive research project was carried out using simulation techniques and sled testing in order to determine way to increase the passive safety of occupants finding themselves in these areas. Main interest was to offer protection in case of a frontal collision, but other critical situations have also been considered, like offering protection when being in out-of-position or during a rollover. Under the current circumstances the 1-point seat belt was found to be the best compromise in combination with a front seat to limit the occupant movement. Based on observations made during the project, other passive safety measures such as safety nets, arm rests, padded walls etc. may be appropriate for consideration in trucks with sidefacing seats.