A laboratory study of the effects of moderate thermal stress on the performance of factory workers∗

Nearly 1000 black and white, male and female factory workers were exposed in single-sex groups of four, each group working a full shift and attending for 1 day only, to air temperatures of 6, 12, 18, 24°C (cold series) and 20, 26, 32, 38°C (hot series). All exposures were at low humidity. Clothing levels were fixed for the cold series and the hot series. The exposures took place in a mobile climate chamber on the factory site and the workers performed a series of tasks to simulate factory work. Significant effects of temperature were recorded and the implications for factory design are noted.