Preventing Blast-Related TBI
In addition to the ballistic and blunt impact threats that combat helmets are designed to protect against, there may be another danger: shockwaves emanating from improvised explosive devices (IEDs) and other blasts. A blast usually generates ballistic projectiles and also causes rapid acceleration of vehicles, objects, and individuals that can lead to blunt impact injuries. However, the propagation of the shock front itself (a phenomenon classified as “Primary” blast injury) is a likely contributor to brain injury.
In support of research to understand the issue of Primary blast-related brain injury, we have conducted live blast testing with a comparison of prototypical instrumented headforms, conducted shock tube testing on helmet liner materials as part of an Army SBIR, and moderated a panel discussion on the issue with the topic’s leading experts at a warfighter protection conference outside of Washington D.C. in late 2011. In addition, the helmet liner in development for the HEaDS UP ATO is being modeled for blast pressure attenuation characteristics by the U.S. Naval Research Laboratory (NRL). This program aims to improve the attenuation of under-helmet pressures by studying new approaches to helmet liner design.
Working with the Blast Simulation Laboratory at the University of Nebraska-Lincoln, we are also studying the effects of helmet shell and liner design on shockwave propagation across and into the head. The state-of-the-art UNL shock tube is capable of accurately simulating IED shockwaves, a difficulty with other traditional shock tube designs. By coupling this work with UNL’s ongoing research into the mechanisms of Primary blast TBI, we will be able to improve the blast protective capabilities of helmets and reduce the occurrence of brain injury in the field.