Abstract
This study evaluates the effects of work/rest schedules as a means of retarding job fatigue and maintaining vigilance performance in hot climates. Six different work/rest schedules were investigated at three levels of heat stress (74°, 82°, and 90° effective temperature). Experimental sessions were 3 hours long for each of the 108 subjects used. Results show that the factors of temperature, work period, and work/rest ratio of the levels utilized in the study did not, by themselves, affect vigilance performance to a high degree. However., when high temperatures, long work periods, and short rest periods occurred in combination, a disproportionate decrement in monitoring performance was observed.