QUANTIFICATION OF CUMULATIVE BLAST DOSE TO SERVICEMEMBERS FROM WEAPON FIRING IN TRAINING AND COMBAT

U.S. servicemembers are often exposed to repeated blasts during training and combat, contributing to increased risk of acute and chronic injuries. There are currently no standard methods to predict injury risks from these blasts. To address this gap, Defense Threat Reduction Agency (DTRA) has called for tools to quantify repeated blast exposures, particularly in combat. This proposal aims to address this need by enhancing CFD Research’s existing Blast Overpressure (BOP) tool to model and predict injury severity for both single and repeated blast exposures, with a focus on vital organs such as the brain, lungs, and whole body (for both primary and secondary blast injuries).CFD Research has previously developed both high-fidelity computational fluid dynamics/finite element models (CFD/FEM) and fast-running models to simulate human exposure to blast forces. The BOP tool is being developed to accommodate blast exposures from all Tier 1 weapons and has been validated using field data from training ranges. Due to the limited availability of benchmark data from actual combat operations, this work will rely on exposure data from both training environments and field weapon tests. A significant challenge in this area is the absence of cumulative dose-response models for repeated blast exposures. While single-exposure criteria have been published, no reliable models currently exist to predict the effects of multiple exposures. This project will focus on filling that gap by developing and partially validating cumulative dose-response models. These models are particularly important for combat scenarios where servicemembers often fire multiple high-power rounds in quick succession, unlike in training where only a limited number of rounds are discharged. Phase I will focus on validating the enhanced BOP tool using existing field data from three weapon systems: mortars, shoulder-mounted weapons, and explosive breaching devices. Blast pressure data, collected using spatially distributed pencil probes and wearable blast gauges to measure the impact of blasts on the human body, will be used for model validation. The predicted blast loads from both training and live-fire rounds will be compared. Novel mechanistic models to quantify the cumulative dose-response from repeated blast exposures will be developed. Phase II will expand the tool’s capabilities to simulate more complex human exposure scenarios that occur during ground combat operations. This will include repeated heavy weapon firings and the effects of incoming explosions, such as blasts, debris, and fire. The goal is to provide actionable insights into injury risks, protective equipment design, and safe exposure limits for servicemembers. The final product will provide valuable information on injury risks posed by repeated blasts in training and combat, inform the protective equipment design, guide policies on safe exposure limits, and support long-term healthcare planning for servicemembers.