Mine Climate — Wet-Bulb Work Limits
Wet-Bulb Work Limits for deep and hot mine planning.
Wet-bulb, not dry-bulb, predicts heat illness underground — sweating is the only cooling a miner has, and WB measures how well it works. The 32.5 °C cutoff appears in multiple codes because human cooling genuinely collapses there; acclimatization buys the band below it, never above.
Formula
Note: Mine ventilation is statutory and life-safety territory: airflow quantities, gas limits and re-entry times must be set by the registered ventilation engineer/manager under your jurisdiction's mining regulations — this calculator is a planning and training aid.
Wet-Bulb Work Limits for deep and hot mine planning. A free mine ventilation & air quality tool — no sign-up, no upload, instant results in your browser.
About Mine Climate — Wet-Bulb Work Limits
Mine Climate — Wet-Bulb Work Limits computes the governing relationship South African / common practice bands: <27.5 unrestricted · 27.5–32.5 managed · >32.5 stop live as you type. Wet-bulb, not dry-bulb, predicts heat illness underground — sweating is the only cooling a miner has, and WB measures how well it works. The 32.5 °C cutoff appears in multiple codes because human cooling genuinely collapses there; acclimatization buys the band below it, never above. Defaults are pre-filled with realistic values for this exact scenario, and the worked example substitutes your numbers step by step so the math is never a black box.
How to use Mine Climate — Wet-Bulb Work Limits
- 1Enter your values — Wet-bulb temperature (sensible defaults are pre-filled).
- 2Read the live results: Wet-bulb reading.
- 3Check the "with your numbers" line to see South African / common practice bands: <27.5 unrestricted · 27.5–32.5 managed · >32.5 stop substituted step by step.
- 4Adjust inputs until the scenario matches yours, then copy or share the result.
Why use Mine Climate — Wet-Bulb Work Limits?
- ✓Instant, free and private — every calculation runs client-side in your browser; nothing is uploaded
- ✓Built on the stated formula South African / common practice bands: <27.5 unrestricted · 27.5–32.5 managed · >32.5 stop with authoritative sources cited on the page (McPherson, M.J., Subsurface Ventilation and Environmental Engineering; Hartman et al., Mine Ventilation and Air Conditioning, 3rd ed.)
- ✓Wet-bulb, not dry-bulb, predicts heat illness underground — sweating is the only cooling a miner has, and WB measures how well it works.
- ✓SI ⇄ Imperial toggle converts your inputs in place, so you can work in the units your drawings use
Frequently asked questions
What formula does the mine climate — wet-bulb work limits use?+
It evaluates South African / common practice bands: <27.5 unrestricted · 27.5–32.5 managed · >32.5 stop, exactly as published. Sources: McPherson, M.J., Subsurface Ventilation and Environmental Engineering; Hartman et al., Mine Ventilation and Air Conditioning, 3rd ed.. The substituted worked example on the page lets you verify every step against the textbook.
How should I read the result — and how far can I trust it?+
Wet-bulb, not dry-bulb, predicts heat illness underground — sweating is the only cooling a miner has, and WB measures how well it works. Mine ventilation is statutory and life-safety territory: airflow quantities, gas limits and re-entry times must be set by the registered ventilation engineer/manager under your jurisdiction's mining regulations — this calculator is a planning and training aid.
When is this calculator the right tool for the job?+
Wet-Bulb Work Limits for deep and hot mine planning. A free mine ventilation & air quality tool. The 32.5 °C cutoff appears in multiple codes because human cooling genuinely collapses there; acclimatization buys the band below it, never above. For neighbouring scenarios, the related tools below cover the same engine with different presets.
Does it support both metric and imperial units?+
Yes — the SI ⇄ Imperial toggle converts the values already in the fields, preserving the physical quantity, so you can flip mid-calculation without re-entering anything.
Related tools
- Mine Climate — Air Cooling Power (M-Scale)
- Mine Climate — Equipment Heat Load
- Mine Climate — Refrigeration Duty Estimate
- Mine Climate — Chilled Water vs Ice Cooling
- Mine Climate — Condensation (Fog) Risk
- Mine Climate — Acclimatization Schedule
- Mine Climate — Intake Air Heating (Cold Climate)
- In-Transit Temperature — Insulated Body, Long Haul
- Erection Engineering — Base Plate Grout Volume
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