The objectives of this study are to evaluate the effect of environmental and metabolic heat on heat-related illnesses in outdoor workers and evaluate the effect of personal factors, including heat acclimation, on the risk of heat-related illnesses in outdoor workers.
The authors identified 47 cases of illnesses from exposure to environmental heat in outdoor workers in Korea from 2010 to 2014, based on a review of workers’ compensation data. They also obtained the information on location, time, and work environment of each heat-related illness.
The major results are that 29 cases (61.7%) occurred during a heat wave. Forty-five cases (95.7%) occurred when the maximum estimated wet-bulb globe temperature (WBGTmax) was equal to or greater than the case-specific threshold value, which was determined by acclimatization and metabolic rate. Twenty-two cases (46.8%) were not acclimated to the heat. Thirty-seven cases (78.7%) occurred after tropical night (temperature above 25°C), during which many people may find it hard to sleep.
Personal risk factors such as heat acclimation as well as environmental factors and high metabolic rate during work are the major determinants of heat-related illnesses.