Center for the Built Environment

This paper describes the development of a chart in which lines of equal comfort are plotted across a wide range of environmental conditions . The chart can be used in the design of outdoor spaces and buildings where air velocity and radiant fields are outside their normal indoor ranges . The basis of the chart is the comfort index DISC, as predicted by the J.B . Pierce Foundation Laboratory two-node thermophysiological model . DISC is a function of skin temperature in cold conditions and of skin wettedness alone in hot conditions . It shows a greater sensitivity to humidity in hot conditions than does ET's . Examples of the chart are given for two clothing levels .