A method of health hazard assessment for human exposure to repeated mechanical shocks

This study describes a health hazard assessment (HHA) method for evaluating human exposures to repeated shocks in tactical ground vehicles. The method predicts the risk of injury to the occupants of a vehicle from the accelerations measured at the seat. The HHA will identify both acute and chronic health risks resulting from either a single exposure, or from multiple exposures to travel over rough terrain. The HHA is based on existing models, human injury data, and experimental data obtained from volunteers subjected to a range of shock profiles and to prolonged repeated shock exposures. The HHA consists of three components: (1) dynamic response models which predict seat‐to‐spine transmission of acceleration; (2) a dose model for exposure to repeated shocks based on fatigue failure theory and subjective tolerance data; and (3) an injury risk model based on the cumulative probability of failure. A biomechanical model is also described which analyzes spinal compression forces in response to shock. This mode...