Dangerous heat stress begins at a wet-bulb temperature of 26.7°C (80°F), with absolute human survivability limits reached at 35°C (95°F).
Occupational health and athletic organizations use the Wet Bulb Globe Temperature (WBGT)—which also accounts for humidity, wind, and solar radiation—to determine safe activity limits.
| WBGT Range | Danger Level | Activity Guidelines |
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