Validation of Mathematical Models for Predicting Physiological Events During Work and Heat Stress

Protective clothing can readily convert a tolerable long-term working condition into a situation in which exposure time is limited by rapidly accumulating heat strain (Kraning and Gonzalez, 1991). It is a challenge to produce simple and universal exposure guidelines for those administrating activities of personnel because effects of different clothing types, workloads and environmental conditions on the expected physiological responses are complex. To reduce uncertainties in estimating safe exposure times, computerized biophysical models of temperature regulation are used to forecast physiological responses under different working and environmental conditions and with different clothing ensembles. Extant models emphasize prediction of body core temperature; expected heat casualty rates are assigned to specific levels of body temperature and then the models are used to forecast the time to reach these specific levels.