What Determines the Climate?

Human experience of thermal climate is determined by a number of factors in the physical environment. It is affected by the ordinary air temperature (T), the tem­perature of the surrounding surfaces (Tg: black globe temperature, related to radiant temperature), air humidity (RH, %), and air movement (V, ms-1). Other important factors include activity level and clothing. There are also small differences due to gender, race, and age, but these factors are of lesser importance. The metabolic pro­cesses of the body produce warmth; increasing the workload increases heat produc­tion. Heat production as a function of activity, clothing, and air speed is given in Table 7.1. Control room work with a low loading gives a heat production in the body of 100 to 130 W, and 160 to 170 W at high loads.