The paper starts by reviewing accident data from UK and other countries which shows that restrained drivers frequently receive brain injuries and face bone fractures from striking their steering wheels in frontal crashes. These fractures are not usually fatal but are extremely unpleasant, requiring skilled surgery and long periods of immobilisation during recovery, and often resulting in permanent disfigurement. Possible counter-measures considered are seat belt pretensioners, air bags, and improved steering wheel designs, and the paper suggests that while pretensioners and air bags would be very effective their cost and complexity will prevent widespread use in high-volume cars for several years. In the meantime improved, less aggressive, steering wheel designs are seen as a good, cheap and quick way of reducing head and face injuries. A practicable safer wheel designed by TRRL and Sheller-Clifford was shown at the 10th ESV Conference at Oxford in 1985, together with a proposed impact test procedure using a flat disc of aluminum honeycomb. The honeycomb crush strength is chosen to be the same as the maximum pressure which the weakest important parts of the human face can withstand without bone fracture, so deformation of the honeycomb during impact indicates a wheel which is dangerously stiff. The present paper describes how this proposed test has since been developed, and gives test results for 15 designs of production wheels. It concludes that the test is easy to carry out and gives repeatable results, and suggests that use of this test in legislation would lead to steering wheel designs which would greatly reduce the risk of brain damage and face bone fracture. (A) For the covering abstract of the conference see IRRD 837684.
Abstract