The wet-bulb globe temperature (WBGT) is a type of apparent temperature used to estimate the effect of temperature, humidity, wind speed (wind chill), and visible and infrared radiation (usually sunlight) on humans. It is used by industrial hygienists, athletes, sporting events and the military to determine appropriate exposure levels to high temperatures. It is derived from the following formula:

${\displaystyle \mathrm {WBGT} =0.7T_{\mathrm {w} }+0.2T_{\mathrm {g} }+0.1T_{\mathrm {d} }}$

where

• T_w = Natural wet-bulb temperature (combined with dry-bulb temperature indicates humidity)
• T_g = Globe thermometer temperature (measured with a globe thermometer, also known as a black globe thermometer)
• T_d = Dry-bulb temperature (actual air temperature)
• Temperatures may be in either Celsius or Fahrenheit

Indoors, or when solar radiation is negligible, the following formula is often used:

${\displaystyle \mathrm {WBGT} =0.7T_{\mathrm {w} }+0.3T_{\mathrm {g} }}$