A Research on Characteristics of Human Heat Stress in Dynamic Hot Environment

Abstract

Because of the global warming phenomenon, extremely high temperature weather occurs more frequently than ever before in recent years, which is leading to a growing number of occupational heat damage incidents. Researches show that when exploded in extreme hot environment for a period of time, human body, especially for those who do manual labor work, may suffer various kind of heat damages including heat stroke, heat exhaustion, heat syncope and heat hyperventilation, etc. the heat damage risk increases with the rising of ex-posed time as well as labor intensity. Meanwhile, China definitely is the largest labor market, where the number of laborers reached 0.8 billion in 2005. These people are much more likely to be exposed in extreme hot environment and more likely to suffer from heat injuries. However, there is not a scientific management system on high temperature working environment in China. Therefore, basic research on human heat stress in hot environment needs to be done, in order to promote the establishment of relative laws, regulations and standards.In this research, 20 adult subjects (11 males and 9 females) are chosen to conduct the experiment in an artificial climate chamber. Taking air temperature (33℃, 35℃, 39℃) and relative humidity (30%, 60%, 85%) into consideration, 8 environment conditions are set according to principle of orthogonality. Exposed in stated environment, the subjects are told to fill in thermal sensation questionnaire. Several physiological parameters are monitored, including oral temperature, skin temperature, blood pressure, heart rate, etc. Besides, the labor intensity is changed from sitting still to walking on a treadmill during the exposure.By setting these experiment conditions, several conclusions are expected to be drawn as follows. First, summarize the relationship between human core temperature or metabolic rate and environmental parameters. Second, observe the heat stress characteristics during different environment and labor intensity. Last but not least, analyze the individual difference and gender difference in heat response to extreme hot environment.