Experimental Research On Thermal Acclimatization And Work Efficiency Under Extreme Heat Environment

With the development of society,workers' operation environment attains more and more attention. Extreme heat environment is ubiquity in the actual production, high temperatures can cause physiological changes in the body, affecting human health, Also people fatigues easily in hot environment, causing a decline in behavioral performance efficiency. There are two practical problems in the study on extreme heat environment: the first one is how to reduce the hazards to the workers, and the second one is how to improve work efficiency. The effects of heat acclimatization training and the the relationship between the workers' physiological parameters and efficiency were studied in a extreme heat environment, in order to provide guidance for the actual production.The chamber with high temperature was constructed. The dry bulb temperature in it is 37±1℃, the relative humidity vary from 20% to 40%,the globe temperature is 41±1℃.University students were chosen as the experimental subjects,and the stair-exercise was done to simulate physical labor in the process of thermal exposure. Test and compare the physiological, integrated thermal sensation and fatigue before and after heat acclimatization training The experimental results indicate that the increasing amount of the oral temperature significantly decreased,and the sweat rates significantly increased,the subjective feeling of the workers also change obviously,it means that heat acclimatization training can increase staff's ability to adapt to the high temperature environment.This paper presents the mathematical relationships between work efficiency and oral temperature, heart rate, PHSI index, thus the dynamic combination of efficiency and physiological was made, providing a method for monitoring the efficiency. Through the analysis of the correlation coefficient, PHSI index best reflects the efficiency of physical labor under extreme heat environment. On this basis, the concept of Ergonomics limit was proposed, and in accordance with the PHSI index, the work efficiency was divided into three levels. The relative curve between ergonomics limit duration and the dry-wet bulb index, corresponding mathematical model were established in the combination with different thermal parameters. They both can be applied to predict the maximal duration for which the staff efficiency will not be less than 85%,thereby providing guidance for the work system, it will also be useful to amend the preventable alarm system, improve the safety state and validity.