Wet-Bulb Globe Temperature (WBGT)
Wet-bulb globe temperature (Yaglou & Minard 1957; ISO 7243): heat-stress index from wet-bulb, globe, and dry-bulb temperatures.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Setting
- Outdoor (in sun)
- Natural wet-bulb temperature
- 25
- Globe temperature
- 35
- Dry-bulb (air) temperature
- 30
Result: Wet-bulb globe temperature 27.5 (outdoor/sun) — map to work-rest activity flags.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- outdoor
- 0.7 x natural-wet-bulb + 0.2 x globe + 0.1 x dry-bulb.
- indoor
- 0.7 x natural-wet-bulb + 0.3 x dry-bulb. Map to ACGIH/NWS work-rest activity flags. A heat-stress index, not a diagnosis.
What you enter
- Setting
- Natural wet-bulb temperature
- Globe temperature (outdoor only)
- Dry-bulb (air) temperature
How this is calculated
Yaglou CP, Minard D. Control of heat casualties at military training centers. AMA Arch Ind Health. 1957;16(4):302-316. (ISO 7243.) Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.