ABSTRACT
This chapter discusses the problems that a worker experiences when exposed to a hot environment and some of the physiological mechanisms that can be brought to bear in alleviating the condition of heat stress. The regulation of body temperature is an important physiological function, and the simplicity with which it can be accomplished in determined and controlled by the worker's ambient environment-by air temperature, air movement, long-wave radiation, and solar radiation. The rate of this evaporative heat loss is directly dependent on the difference between the effective vapor pressure of the moisture on the skin and that in the ambient air. Higher velocities are provided in some cases when workers are exposed to intense radiant heat for short periods. Radiant heat is the most common source of heat that workers encounter in severe stress conditions. Excessive heat has physiological effects on the worker, and a comfortable working environment is recognized as a good investment for worker cooperation and welfare.
