A Finite Element Study of Blast Overpressure on the Skull With and Without Helmet

The use of advanced personal armor, especially the helmet, during combat has significantly reduced the incidence and severity of life threatening penetrating injuries from gunshot and blast shrapnel to the head and improved the overall survival rate of soldiers in combat [1]. On the other hand, the number of blast related injuries (68%) has increased to more than 4 times that of gunshot wounds (15%) and other injuries (17%), among which blast-induced traumatic brain injury (bTBI) has became the signature wound of the U.S. armed forces in Iraq and Afghanistan due to increased use of improvised explosive devices (IED) and rocket-propelled grenades (RPG) by the insurgents [2–4]. It is well known in detonation physics that the presence of a close proximity surface will increase the overpressure on the target due to blast wave reflection [5, 6]. The helmet, which has saved many lives from otherwise fatal penetration and blunt impact injuries, may unfortunately also serve as a reflecting surface and pose increased blast injury threat to the head. Consequently, the current study was designed to compare blast overpressures on the skull with and without helmet using a human head computational model.