Fundamental study on sensation of dryness and indoor thermal environmental conditions

Abstract

For establishing the basis of clarifying the conditions to create indoor thermal environment without discomfort due to sensation of dryness in winter (dry season), several kinds of questionnaire surveys were conducted. The questionnaire survey to great mass of office workers and students revealed that more than half of them experienced discomfort due to dryness in indoor spaces and that they sensed dryness most in the throat, followed by the lip, eyes, and face. At the same time, based on the surveys for occupants during sedentary work, the relationship between the sensation of dryness and the thermal environmental conditions such as air temperature, humidity, and wind velocity was studied. The results showed that the sensation of dryness could be caused more intensively when the air temperature or the wind velocity is higher or the humidity is low. This might correspond with the physical mechanism of moisture evaporation from skin or mucous membrane, and suggest the alternatives of indoor thermal environmental control in winter other than humidification.