Determining patterns of the influence of low temperatures of the external environment on head protection for a mountain rescuer

Abstract

The basic principles of the need to develop a methodology for determining the level of protection of the rescuer's head during search and rescue operations in mountainous areas under conditions of low temperatures have been substantiated in this paper. The shortcomings of the existing system for ensuring the safe mode of search and rescue operations of rescuers in mountainous areas at low temperatures have been identified. Based on the statistical analysis of search and rescue operations, it was established that the greatest number of them occurs in the fall-winter period. It was determined that on the territory of the Carpathian Mountains the largest number of search and rescue operations is carried out in Zakarpattia, Ivano-Frankivsk, and Lviv oblasts. An analysis of working conditions was carried out. The results of studies into the effectiveness of thermal insulation of protective clothing of a mountain rescuer were analyzed. Mathematical modeling of heat and mass transfer in the body of a mountain rescuer was carried out using MATLAB software. Modeling of changes in temperature processes in the volume of the rescue head model was carried out under the influence of environmental temperatures: –10 °C, –20 °C, –30 °C, and a metabolic rate of 600 W/m2. Modeling was carried out on a 4-layer segment of the head. It was established that the effect of low temperatures on the face, head and, accordingly, the hypothalamus through the frontal part of the rescuer's skull leads to disability already at minute 17 in the absence of head protection equipment. The use of a model for predicting a decrease in body temperature as a result of exposure to the external environment and the level of protection by the rescuer's individual means will determine the time of risky decrease in brain temperature (up to +32 °C) and prevent a negative impact on the health of the rescuer