Wet-bulb globe temperature

From Glossary of Meteorology

wet-bulb globe temperature[edit | edit source]

(Abbreviated WBGT.) A simple measure of human heat stress in direct sunlight that takes into account air temperature, wind speed, and radiant heat load (from the sun and other sources). The index combines the dry-bulb temperature Td with two derived parameters, natural wet-bulb temperature Tnw and globe temperature Tg, as follows:
WBGT equation
The WBGT value is considered along with metabolic rate to assess the potential for heat stress in occupational and athletic settings. It differs from the heat index, which takes into consideration the air temperature and humidity and is calculated for shady areas (ISO 2017).

International Organization for Standardization (ISO) 2017: ISO 7243: Ergonomics of the thermal environment—Assessment of heat stress using the WBGT (wet-bulb globe temperature) index. Accessed 25 September 2019. Available at https://www.iso.org/obp/ui/#iso:std:iso:7243:en.


Term edited 25 September 2019.


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