Heat is a major weather-related hazard.
Although heat hazards are common during outdoor physical activity, heat-related illness and fatalities are preventable.
Heat stress is commonly measured by the Heat Index or the “feels like temperature”.
An alternative method is the wet bulb globe temperature (WBGT).
WBGT estimates the effect of temperature, relative humidity, wind speed, and solar radiation on humans.
Why is it called Wet Bulb Globe Temperature?
WBGT is derived from a combination of temperatures from three thermometers:
Black globe - for solar factor (sun angle and cloud cover)
Wet bulb - for humidity
Dry bulb - for the ambient temperature
WBGT values of 90 or greater are dangerous for strenuous outdoor activities.
WBGT has been used for decades by military agencies, OSHA, and marathon organizers.
The American College of Sports Medicine bases its guidelines for the intensity of sports practices on WBGT.
WBGT is helpful for anyone performing strenuous outdoor activities, whether they are workers or athletes.
WBGT can be used to establish guidelines for outdoor exercise work.
Guidelines vary geographically since temperatures fluctuate by region, and people’s response to exercising or working in heat may also vary by the geographic region.
