Controlling heat stress - administrative versus physical control.

The collective effectiveness of several heat stress prevention measures has been evaluated. The relative merits of both physical and administrative controls and their interrelationships have been explored. It is concluded that a combination of physical and administrative control is more effective than any single physical or administrative control in managing heat stress. The use of the preventive measures discussed provided protection to a labor force of 120 employees working approximately 2.4 million man-hours over a six-year period where temperatures average 26.6 degrees C Wet Bulb Globe Temperature (WBGT) during the nonsummer months and 34.4 degrees C WBGT during the summer months. Only three documented cases of heat stress were encountered during this period.