Why Using Wet Bulb Globe Thermometers to Measure Heat Exposure for Construction Employees is Recommended

Environmental heat is more than just temperature. Four factors contribute to heat stress in workers:

• Air temperature.
• Humidity. High relative humidity makes it difficult for the body to cool itself through sweating.
• Radiant heat from sunlight or artificial heat sources such as furnaces.
• Air movement. In most situations, wind helps workers cool off.

An environmental heat assessment should account for all of these factors. OSHA recommends the use of wet bulb globe temperature (WBGT) monitor to measure workplace environmental heat.