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ISO 7243:2017 WBGT Screening — Heat Stress Screening Thresholds

International WBGT screening standard for heat stress assessment.

Open ISO 7243:2017 WBGT Screening in the interactive Guidance Wiki →

Authority
ISO
Jurisdiction
Global
Legal status
Technical Standard
Rule type
Screening Limit
Standard ID
HGC-019

Governing formula

No standalone formula is published for this standard; see programmable logic and parameters below.

Screening thresholds

Acclimatized workers

WBGT (°C)Light
180 W		Moderate
300 W		Heavy
415 W		Very heavy
520 W
2430°C limit28°C limit26°C limit25°C limit
2530°C limit28°C limit26°C limit25°C limit
2630°C limit28°C limit26°C limit25°C limit — exceeded
2730°C limit28°C limit26°C limit — exceeded25°C limit — exceeded
2830°C limit28°C limit26°C limit — exceeded25°C limit — exceeded
2930°C limit28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3030°C limit28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3130°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3230°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3330°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3430°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3530°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded
3630°C limit — exceeded28°C limit — exceeded26°C limit — exceeded25°C limit — exceeded

Unacclimatized workers

WBGT (°C)Light
180 W		Moderate
300 W		Heavy
415 W		Very heavy
520 W
2429°C limit26°C limit23°C limit — exceeded20°C limit — exceeded
2529°C limit26°C limit23°C limit — exceeded20°C limit — exceeded
2629°C limit26°C limit23°C limit — exceeded20°C limit — exceeded
2729°C limit26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
2829°C limit26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
2929°C limit26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3029°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3129°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3229°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3329°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3429°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3529°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded
3629°C limit — exceeded26°C limit — exceeded23°C limit — exceeded20°C limit — exceeded

Inputs

Required inputs: wbgtC, metabolicRateW

Optional inputs: acclimatization

Sources

Update history

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