The purpose of the present study is to determine the limits of overhead radiation to which man in thermal neutrality can be exposed without feeling discomfort. Thermal neutrality for a person is defined as a condition in which he prefers neither a higher nor a lower ambient temperature level. Thermal neutrality is a necessary condition for a person to attain thermal comfort. However, this condition is not always sufficient. It is a further requirement that no local warm or cool discomfort is experienced on any part of the body. Overhead radiation from a heated ceiling can create such local discomfort: either warm discomfort at the head or cold discomfort at the feet (or both).