Pedestrian comfort using clothing values and body temperatures

Outdoor human comfort in an urban environment may be affected by a wide range of weather and human factors. The paper describes a research study investigating the complex relationship between physical and psychological parameters on human comfort levels. The study determined that the air temperature and the wind speed have a clear influence on the human comfort level while the solar radiation and relative humidity do not show a strong relationship. The effects of adaptation were shown clearly using over 8000 data sets with clear differences between five European countries. The importance of adaptation was further shown by the low correlation values between comfort and certain meteorological parameters. It is suggested that the subjective parameter of human comfort level is not well suited to determine guidelines for the design of outdoor spaces. Controlled tests in a wind tunnel have shown that the skin temperature (forehead and hand) has the potential to be used as a surrogate for comfort. With respect to the climatic variations outlined in this paper, it was discovered that lower forehead temperatures resulted in lower comfort values nearly independent of the meteorological parameters. Therefore, in the current study it is found that the skin temperature may be used as an objective parameter to determine human outdoor comfort levels although further tests will be necessary.