Convert Barye to Millimeters of Water
Convert Barye (Ba) to Millimeters of Water (mmH₂O) instantly and accurately.
Conversion Formula
mmH₂O = Ba × 0.01019716213
About Barye
The barye (Ba) is the CGS unit of pressure - 1 dyne/cm² = exactly 0.1 Pa = 1 µbar. Standard atmosphere = 1,013,250 Ba. It dominated physics and laboratory science from the mid-19th century until SI adoption. Legacy acoustic CGS literature used 1 barye (0.1 Pa) as the underwater reference pressure, creating a 100 dB offset versus the modern 1 µPa reference - a critical correction when comparing historical and modern underwater acoustics databases. Still encountered in classical fluid mechanics derivations and early 20th-century meteorological literature. 1 Ba = 0.1 Pa.
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.
Quick Reference Table
| Barye (Ba) | Millimeters of Water (mmH₂O) |
|---|---|
| 1 Ba | 0.0101972 mmH₂O |
| 2 Ba | 0.0203943 mmH₂O |
| 5 Ba | 0.0509858 mmH₂O |
| 10 Ba | 0.101972 mmH₂O |
| 25 Ba | 0.254929 mmH₂O |
| 50 Ba | 0.509858 mmH₂O |
| 100 Ba | 1.01972 mmH₂O |