The effect of hardhats on head and neck response to vertical impacts from large construction objects

Abstract

We evaluated the effectiveness of hardhats in attenuating head acceleration and neck force in vertical impacts from large construction objects. Two weight-matched objects (lead shot bag and concrete block) weighing 9.1kg were dropped from three heights (0.91m, 1.83m and 2.74m) onto the head of a 50th percentile male Hybrid III anthropomorphic test device (ATD). Two headgear conditions were tested: no head protection and an ANSI Type-I, Class-E hardhat. A third headgear condition (snow sport helmet) was tested at 1.83m for comparison with the hardhat. Hardhats significantly reduced the resultant linear acceleration for the concrete block impacts by 70–95% when compared to the unprotected head condition. Upper neck compression was also significantly reduced by 26–60% with the use of a hardhat when compared to the unprotected head condition for the 0.91 and 1.83m drop heights for both lead shot and concrete block drop objects. In this study we found that hardhats can be effective in reducing both head accelerations and compressive neck forces for large construction objects in vertical impacts.