Computer Simulation of Thermoregulatory Responses to Heat Stress: A Future Work Design and Training Tool

A mathematical model of human thermoregulation was developed to simulate thermoregulatory responses of man exposed to heat stress environments. The model was validated with experimental results of a man pedalling in environments of 35 and 45°C dry-bulb and 33 mm Hg water vapor pressure. The model inputs of body segment temperatures, thermal characteristics, basal blood flows, basal heat production, and of environmental and task characteristics permitted the model to be “individualized” for a specific subject, environment, and task. The model outputs of body segment temperatures, blood flows, and sweat loss at designated intervals permitted observation of the dynamic thermoregulatory responses over a 60 minute exposure period. The model was successful in predicting the change in thermal responses of a clothed man working in heat stress environments. Over the 60 minute exposure at 45°C the mean absolute difference between experimental and simulated values of head skin temperature was 0.28°C. The difference for trunk mean skin temperature was 0.12°C; for body mean skin temperature, 0.29°C; and for internal body temperature, 0.53°C.