144 / 2021-10-06 13:38:29

Predicted heat strain as the basis for planning rescue work in a hot environment

mine rescuer, difficult microclimate conditions, breathing apparatus, cooling vests, duration limited exposure, predicted heat strain, specialist protective clothing

In the paper calculation methods for determining the heat strain of mine rescuers working in climatic hazard conditions were presented. Different variants of the rescuers working conditions were analyzed: the composition of the atmosphere in accordance with the regulations - work without the use of apparatus, the unbreathable atmosphere - work with the use of breathing apparatus, climate hazard - work with a minimum amount of clothing, risk of explosion or active fire fighting - work in full rescue clothing. Example calculations were based on the algorithms and formulas included in the PN-EN ISO 7933 standard "Ergonomics of the thermal environment - Analytical determination and interpretation of heat stress using calculations of the predicted heat strain" as well as the results and conclusions of the RESCLO research project "Development of protective clothing for mine rescuers" implemented under NCBiR (National Centre for Research and Development) strategic research project entitled "Improvement of work safety in mines".

The paper presents the problem of the influence of work in closed circuit self contained breathing apparatus with compreesed oxygen or open circuit compressed air breathing apparatus and the use of measures improving the comfort of work on the thermal balance of the rescuer’s body. Issues not regulated by the standard and regulations were indicated. A several examples of rescue works were discussed, for which there are no tables of rescuers working time in difficult microclimate conditions included in the regulation on mines rescue.

Selected rescue operations were analyzed during which the rescuers fainted or suffered from heat stroke due to overheating of the body. The paper presents the method of using computer calculation methods to forecast the heat strain of rescuers at each stage of work in order to optimalize work and rest cycles in order to prevent overheating of rescuer’s organisms. The purpose of this paper is to present the progress in scientific research related to the work of rescuers in a hot environment and to propose a method of planning rescue work based on the projected heat balance of rescuer’s organisms.