Mining heat stress overlay with hot-work-site trigger and mining-specific controls.
Open MSHA Mining Heat Stress Overlay in the interactive Guidance Wiki →
No standalone formula is published for this standard; see programmable logic and parameters below.
| WBGT (°C) | Light 180 W | Moderate 300 W | Heavy 415 W | Very heavy 520 W |
|---|---|---|---|---|
| 24 | Not triggered | Not triggered | Not triggered | Not triggered |
| 25 | Not triggered | Not triggered | Not triggered | Not triggered |
| 26 | Not triggered | Not triggered | Not triggered | Not triggered |
| 27 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 28 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 29 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 30 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 31 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 32 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 33 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 34 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 35 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 36 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| WBGT (°C) | Light 180 W | Moderate 300 W | Heavy 415 W | Very heavy 520 W |
|---|---|---|---|---|
| 24 | Not triggered | Not triggered | Not triggered | Not triggered |
| 25 | Not triggered | Not triggered | Not triggered | Not triggered |
| 26 | Not triggered | Not triggered | Not triggered | Not triggered |
| 27 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 28 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 29 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 30 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 31 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 32 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 33 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 34 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 35 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
| 36 | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) | Hot work site (≥26°C) |
Required inputs: wbgtC
Optional inputs: acclimatization
This standard was added to the calculator.
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