Experiment And Research On The Human Physiological Parameters In Hot Environment With Strong Radiant Heat Of Fixed Direction

As the development of the society and the progress of the cognition, labor's health and safety in the production attain more attentions. The variety tendency of human physiological parameters and corresponding extreme physiological values are the main methods to evaluate the heat stress under heat exposure. For a long time, people try to find an evaluating index for heat tolerance which is accurate and easily to be measured.At industrial work places, for example, in metal or glass industry and also at outdoor work in the sun, a considerable part of heat stress is related to thermal radiation. The radiant heat not only affect on the surface of skins, but also into the depth of human body. So it would strengthen the effect of heating. Focused on this problem, approximately 85 climatic chamber experiments were performed with 71 male subjects and 14 female subjects involved to study the heat stress in different climates. According to"Classified standard of working in the hot environment"GB/T4200-1997, the people's tolerances were measured at 4 levels with different quantity of radiant heat (1.0 kW/m2, 1.5 kW/m2, 2.0 kW/m2).Based on the experiment of collecting samples, the variation tendency of physiological parameters during the process was obtained. The physiological limit values of human bodies at heat exposure limit were achieved. The influence of heat environment parameters to heat tolerance of human body was analyzed.Heat tolerance abilities of human bodies under the conditions of extreme heat environment were evaluated according to subjective and objective methods. A new subjective evaluation system different from ASHRAE's heat comfort evaluation system is proposed. Score in new system can reflect human body heat tolerance ability. Then the score was acquired when people meet the tolerant limit.The physiological stress index developed from D.S. Moran was revised instead of rectal temperature by oral temperature and applied to evaluate heat exposure limit and healthy heat exposure, which can definitely reflect body heat exposure condition.The relationship between WBGT, TEQ and PSImax was analyzed. The result was that contrast with WBGT, TEQ was more suitable to evaluate the climatic conditions with high radiant temperature.Synthetically considering the experiment results and the studies by other scientists from domestic and overseas, suggestions were provided for revision of the "Classified standard of working in the hot environment", which was practiced in our country at present.