Use a smartphone app for predicting human thermal responses in hot environment

Abstract

The object of this study is to predict of human thermophysiological state in hot environment to prevent heat stress or heat stroke. A key issue is the need to design effective tools for heat stroke risk assessment taking into account environmental conditions, physical activity, characteristics of human clothing and protective equipment. A mobile application has been developed, which, unlike existing analogs, provides users with data on the safe time of human under selected environmental conditions. The mobile application uses the method of mathematical modeling to predict important indicators of human thermophysiological state: body temperature, sweat evaporation, body water loss. The mathematical model takes into account the generation of metabolic heat, the transfer of heat inside the body, and the heat exchange of a human with the environment. This paper reports the results of using a mobile application for predicting human thermal responses under hot environmental conditions. With the help of the application, it was possible to determine the time of a human's safe stay depending on the intensity of his/her activity and the characteristics of his/her clothing. It is shown that walking at a speed of 6 km/h in a military uniform is safe for 1 hour at an air temperature of 36 °C. Running at a speed of 8 km/h under such conditions becomes risky already after 15 minutes due to overheating of the human body. The developed information technology is designed to warn about heat stress or heat stroke of people who are under hot conditions in order to preserve their health and work capacity. The received predicting data should be considered as one of the theoretical measures to prevent human heat stress under hot environmental conditions