Venting of a Ballistic Helmet in an Attempt to Reduce Thermal Loading

摘要

Ballistic helmets are designed primarily to protect the head against high-speed impact from fragmentation munitions. The Australian Defense Forces (ADF) have recently introduced into service a composite ballistic helmet. This ballistic helmet is similar in shape to the US Army PASGT helmet on which it is based. When designing these ballistic helmets scant attention was given to the thermal loading on the wearer. Laboratory trials however, have shown that some soldiers have experienced 'hotspots' on the front of the head when wearing the ADF ballistic helmet in hot environments. The ballistic helmet is an integral component of the personal armour system and must be worn when wearing a fragmentation or ballistic vest regardless of the environmental conditions. In order to reduce the thermal loading, venting of the helmet was proposed. This report examines airflow under a ballistic helmet and the effect of venting on thermal and vapor resistance using a sweating hotplate. From this work venting does not appear to provide an adequate solution to reducing the thermal load imposed by a ballistic helmet.