Atmospheres to Inches of Water
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atm
inH2O
Quick reference
| Atmospheres (atm) | Inches of Water (inH2O) |
|---|
Formula
Inches of Water = atmospheres × 406.78231
Multiply the atmospheres value by 406.7823147549671 to get inches of water. To reverse — divide inches of water by 406.7823147549671 to get atmospheres.
About this conversion
The atmosphere (atm) is a reference pressure unit equal to the average atmospheric pressure at sea level: 101,325 pascals. Learn more →
Inches of water column (inH₂O) is used in HVAC and low-pressure measurement, equal to approximately 249 pascals. Learn more →
Source: NIST International Reference