Convert Millimeters of Water to Centimeters of Water
Convert Millimeters of Water (mmH₂O) to Centimeters of Water (cmH₂O) instantly and accurately.
Conversion Formula
cmH₂O = mmH₂O × 0.1
About Millimeters of Water
One millimetre of water column (mmH₂O) = pressure from 1 mm of fresh water at standard gravity = exactly 9.80665 Pa. Preferred for very low differential pressures in HVAC: ductwork static pressures, fan curves, filter resistance, and building pressurisation are in mm WC. Gas valve operating pressures are typically 0.5-3 mm WC; clean-room cascade differentials 12-25 mm WC. A domestic gas hob manifold operates at ~20 mm WC on natural gas. Also used in spirometer calibration and hospital oxygen delivery systems. 1 mmH₂O = 9.80665 Pa.
About Centimeters of Water
One centimetre of water column (cmH₂O) ≈ 98.07 Pa - the clinical pressure unit for respiratory and intravascular measurements. Mechanical ventilator settings are in cmH₂O: peak inspiratory pressure (PIP) 15-30 cmH₂O; PEEP 5-15 cmH₂O; plateau pressure should stay below 30 cmH₂O to avoid lung injury. Lumbar puncture CSF opening pressure is normally 8-20 cmH₂O. CPAP/BiPAP therapy for sleep apnea: 4-20 cmH₂O. Central venous pressure is also reported in cmH₂O. 1 cmH₂O = 98.0665 Pa.
Quick Reference Table
| Millimeters of Water (mmH₂O) | Centimeters of Water (cmH₂O) |
|---|---|
| 1 mmH₂O | 0.1 cmH₂O |
| 2 mmH₂O | 0.2 cmH₂O |
| 5 mmH₂O | 0.5 cmH₂O |
| 10 mmH₂O | 1 cmH₂O |
| 25 mmH₂O | 2.5 cmH₂O |
| 50 mmH₂O | 5 cmH₂O |
| 100 mmH₂O | 10 cmH₂O |