1999 Volume 42 Issue 2 Pages 294-300
The chin bar of a motorcycle helmet protects the rider from facial and head injuries. An experimental model was developed to evaluate the behavior of the chin bar on direct facial impact, and compared this model with the Snell Memorial Foundation and British Standard tests. In the model, a headform was secured against the interior of the chin bar, then dropped to impact a flat anvil. The maximum acceleration and Head Injury Criterion(HIC) were measured to assess the impact-absorbing capability of the chin bar. The results showed that this approach provides a more realistic and accurate assessment of the ability of the chin bar to protect against head injuries than the Snell or British Standard systems. A chin bar consisted only of plastic shell and comfort foam offers inadequate protection. An impact-absorbing liner is essential to increase the protective performance of chin bar. An appropriate cushioning structure at impact shell area could further improve the impact-absorbing capability. The stiffness at the connected portion between the chin bar and the helmet should be reduced to enhance the cushioning effect.