Occupants' climate-controlling behavior in Japanese residences

Abstract

In this chapter, occupants' behaviors will be described from the viewpoint of reducing thermal stress, based on the field survey data in Chap. 19. Field surveys were conducted in occupied houses in Hyogo and Osaka, Japan, from August to September 2003. In mixed mode, occupants combined air conditioning, natural ventilation, and electric fans. Especially the occupants switched between air conditioning and natural ventilation (+ fan use) controlled the indoor temperature. The use of natural ventilation and electric fan suppressed the start of air conditioning at the humidity ratio of 15 g/kg (DA) or less, at room temperature of 30 °C or less. However, when the indoor air temperature exceeds 30 °C, the start of air conditioning has no influence of natural ventilation and electric fan use, and there was no effect in suppressing air conditioning. Occupants started air conditioning at room temperature lower than wet-bulb globe temperature (WBGT) of 29 °C. Therefore, WBGT of 29 °C is considered to be hot limit of adaptation.