Thermal comfort in warm and humid atmospheres: Observations on groups and individuals in Singapore

The majority of sedentary lightly clad acclimatized European men and women in Singapore are reasonably comfortable in relation to their indoor thermal environment provided the effective temperature does not exceed 78° F. or fall below 73° F. European women, who were, however, older as a group than the other subjects, preferred rather cooler conditions than European men or Asian men and women. There were considerable variations between individuals in their comfort tolerance for various levels of warmth, but the average opinion of one individual was usually consistent provided sufficient votes were collected to provide an adequate sample at each level of warmth. When the dry-bulb temperature was above 83° F., increasing the average air movement from a still to a more turbulent condition added to the comfort of the majority of European men and women. When the temperature was below 83° F. for men and 81° F. for women, moderately good air movement was rather less comfortable than slight air movement; whereas below 77° F. still air was more comfortable than slight or moderate air movement. Increasing the air movement within a compartment can thus be used for combating thermal discomfort only within a limited range of warmth, but within that range it is extremely useful. Two groups of naval ratings who had been living in a warship in a tropical climate were reasonably comfortable at similar levels of warmth to the men in Singapore, but they were less tolerant of levels of warmth above the comfort zone.