Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Wet Bulb Globe Temperature (WBGT)

The Wet Bulb Globe Temperature can be used to measure the general Heat-Stress index.

The Wet Bulb Globe Temperature (WBGT) can be measured by 

  • the black globe temperature 
  • the natural wet-bulb temperature
  • the shade air temperature

Outdoor with Solar Radiation

The Wet Bulb Globe Temperature (WBGT) for outdoor conditions:

WBGT = 0.7 Tnwb + 0.2 Tg + 0.1 Ta                                (1)

where 

WBGT = the Wet Bulb Globe Temperature (oC)

Tnwb =  the natural wet-bulb temperature (oC)

Tg = the black globe temperature (oC)

Ta = the (shade) air temperature (oC)

The black globe thermometer (Tg)

A 150 mm (6 inch) black globe with a thermometer located at the centre.

Represents the integrated effects of radiation and wind.

The natural wet-bulb temperature (Tnwb)

A thermometer with its bulb covered with a wettened cotton wick supplied with water. Evaporation cools the thermometer. Not shielded from wind or radiation.

Represents the integrated effect of humidity, wind and radiation.

The (shade) air temperature (Ta)

Measured by a thermometer shielded from radiation.

Indoor - with negligible Solar Radiation

The Wet Bulb Globe Temperature (WBGT) can be calculated for indoor conditions as 

WBGT = 0.7 Tnwb + 0.3 Tg                            (2)

Related Topics

  • Air Psychrometrics

    Moist and humid air calculations. Psychrometric charts and Mollier diagrams. Air-condition systems temperatures, absolute and relative humidities and moisture content in air.
  • Physiology

    Human physiology vs. air quality, comfort temperatures, activity and metabolic rates. Health effects of gases adn polutions like carbon monoxide and more.

Related Documents

Search

Search is the most efficient way to navigate the Engineering ToolBox.

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

Translate this Page

Translate this page to Your Own Language .

About the Engineering ToolBox!

Privacy Policy

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

Citation

This page can be cited as

  • The Engineering ToolBox (2010). Wet Bulb Globe Temperature (WBGT). [online] Available at: https://www.engineeringtoolbox.com/wet-bulb-globe-temperature-WBGT-d_1630.html [Accessed Day Month Year].

Modify the access date according your visit.

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter

















































3.27.8

.