PRELIMINARY REPORTS USE OF THERMAL IMAGERY FOR ESTIMATION OF CORE BODY TEMPERATURE DURING PRECOOLING ,E XERTION, AND RECOVERY IN WILDLAND FIREFIGHTER PROTECTIVE CLOTHING

Background. Monitoring core body temperature to identify heat stress in first responders and in individuals participating in mass gatherings (e.g., marathons) is difficult. Objective. This study utilized high-sensitivity thermal imaging technology to predict the core temperature of human subjects at a distance while performing simulated field operations wearing thermal protective garments. Methods. Six male subjects participating in a study of precooling prior to exertion in wildland firefighter thermal protective clothing had thermal images of the face captured with a high-resolution thermal imaging camera concomitant with measures of core and skin temperature before, during, and after treadmill exercise in a heated room. Correlations and measures of agreement between core temperature and thermal imaging‐based temperature were performed. Results. The subjects walked