Heat Stress Calculator

Assess heat stress risk and determine safe work practices in hot environments.

°C
Air temperature in shade
°C
With natural air movement
°C
Radiant heat measurement
%
hours

Heat Stress Guidelines

ACGIH TLVs for Heat Stress (WBGT in °C)
Workload Acclimatized Not Acclimatized Action Required
Light 30.0 28.0 Caution - Increased monitoring
Moderate 27.5 25.0 Extra breaks, hydration
Heavy 26.0 22.5 Work/Rest cycles required
Very Heavy 25.0 20.0 Consider stopping work
Heat Illness Symptoms
Condition WBGT Range Symptoms First Aid
Heat Rash Any Red clusters of small blisters Keep skin dry, powder
Heat Cramps 26-30°C Muscle pain/spasms Rest, cool water, stretching
Heat Exhaustion 28-32°C Heavy sweating, dizziness Cool area, water, medical
Heat Stroke 30°C+ No sweating, confusion EMERGENCY - Call 911