Michael Dean Taggart, PhD, MPH, CIH, CSP

Abstract

In the year 2000 alone, OSHA recorded 21 workplace fatalities due to heat stress. There were an additional 2,554 heat stress injuries sufficiently serious to require days away from work. OSHA noted that heat stress-related injuries are likely under-reported as many employers fail to recognize the symptoms of heat-related illness. It should further be recognized that heat stress will impair the metal and physical abilities of employees. There is no way to estimate the number of fatalities and injuries in which heat stress may have plated a significant role.

There are many methods for evaluating the hazard due to conditions of heat stress. The American Conference of Governmental Industrial Hygienists, ACGIH, publishes a method known as the Wet Bulb Globe Temperature Index (WBGT). Currently OSHA has no heat stress standard and is enforcing the WBGT recommendations of the ACGIH under section 5(a)(1) of the OSH Act, the General Duty Clause.

Heat Stress and Heat Strain

"Heat stress" refers to adverse conditions to which employees are exposed. Stressors include air temperature, humidity, radiant energy (e.g. infra-red radiation), clothing worn, air movement, and others. "Heat strain" refers to the response of the body to heat stress, i.e. heat related illness.

原文下载：IH for the CSP 6: Wet Bulb Globe Temperature Index