Warmth and Performance : An Investigation in the Tropics

An account is given of an experimental investigation at Singapore into the effect of unusual levels of environmental warmth on the performance of skilled tasks by young European men living in the tropics. Three experiments on manual tracking, one on prolonged visual watch-keeping and one on high speed decision taking are reported. Broadly speaking the main findings of previous experiments on artificially heat-acclimatized men wore confirmed. Performance first deteriorated some-where between about 81° and 86° f on the effective temperature scale, although there was some evidence that the critical region was lower for warm humid climates than for warm dry ones. The men at Singapore appeared to be rather more disturbed by unusually cool climates than artificially heat acclimatized men in England.