Climate and comfortable indoor temperatures for the built environment-interpreting the worldwide data

Since the publication of Bedford's classic study in 1936, numerous researchers have collected data on people's thermal comfort in everyday conditions. The principal assemblages of such data are those of Humphreys (1975, 1978, 1981), de Dear et al (1997), de Dear (1998) de Dear and Brager (1998) and McCartney and Nicol (2001). In addition there exist numerous studies not included in any such assemblage. These data come from a variety of climates and countries, and from people in buildings that are heated or cooled mechanically, and from buildings operating without either heating or cooling. This paper compares some of the more recent findings with the patterns revealed by Humphreys' 1975-8 meta-analysis, and considers the mean comfort votes and the temperatures found to be comfortable, in relation to indoor temperature, to the climate and to the presence of heating or cooling. It is shown that people are often comfortable in a wider range of conditions than would be expected from ISO 7730 or the ASHRAE Standard. Among the data are samples from five cities in Pakistan. These data are considered against their international background and in relation to their regional climate. The data may be used to suggest indoor temperatures that are comfortable, yet can be provided with modest energy consumption. (author)