Noise appeared to affect the quality of work but there are no simple relationships between noise and human performance. Corrective measures such as headphones and soundproof construction materials can be used. Heat stress is a problem for those who work outdoors as well as who work around furnaces, boilers, dryers and other heat-producing equipment. Heat affects physical and mental tasks. Tasks that require fine finger dexterity are more affected than other grosser manual activity.
Wind chill is a major factor affecting outdoor work.
Stressors that occur in combination create a far more dangerous work environment than stressors in isolation. Fatigue Fatigue is a physiological phenomenon, or a reduction in performance capability that can be restored by rest. Work Schedules - refer class notes on discussion of job redesign options.