Experimental evaluation of chin bar on head injury in facial impact

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 Snel l 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 m easured to assess the impact-absorbing capability of the chin bar. The resu lts showed that this approach provides a more realistic and accurate assess ment of the ability of the chin bar to protect against head injuries than t he Snell or British Standard systems. A chin bar consisted only of plastic shell and comfort foam offers inadequate protection. An impact-absorbing li ner is essential to increase the protective performance of chin bar. An app ropriate cushioning structure at impact shell area could further improve th e impact-absorbing capability. The stiffness at the connected portion betwe en the chin bar and the helmet should be reduced to enhance the cushioning effect.