Physiological deviations in the body when working in a heating environment in shunt shielding personal protective equipment

Abstract

Introduction. The article presents results of the study of the human body functional state when using a set of shielding personal protective equipment during modelling of electrical staff occupational activity in a hot environment.
 Materials and methods. The studies were carried out in the climatic chamber with an air temperature 35.5 ± 0.5 °C and a WGBT index of 30.0 ± 0.8 °C. Studies of the human body functional state were conducted with the participation of twelve volunteers who used a set of shunting shielding personal protective equipment and a control clothing set. The values of body temperature, skin both temperature and humidity, clothing temperature and humidity under dressing were recorded. General heat and local moisture perceptions were evaluated. During the research, the heart rate and metabolic rate were recorded by indirect calorimetry. The values of the average skin & body temperature, heart rate increase, changes in heat storage rate, as well as moisture exchange indicators were calculated. 
 Results. The results of the physiological cost assessment indicate that the use of a shielding personal protective equipment set compared to the control set led to a greater increase in core temperature (by 47.7%), higher values of average body temperature (by 1.3%), heat storage rate (by 24.2%), heart rate (by 24.7%), the metabolic rate (by 20.7%), moisture loss (by 55.6%).
 Limitations. The study had limitations due to sample size of the included volunteers.
 Conclusion. The data obtained indicate a significant change in the human body functional state and a critical risk of overheating when using shielding personal protective equipment. The use of a shielding clothing increases the physiological and energy cost of work, which is expressed in a gain in the metabolic rate level, oxygen consumption, and a work category elevation from IIa to IIb.