Convert Centimeters of Water to Technical Atmospheres
Convert Centimeters of Water (cmH₂O) to Technical Atmospheres (at) instantly and accurately.
Conversion Formula
at = cmH₂O × 0.001
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.
About Technical Atmospheres
One technical atmosphere (at) = exactly 1 kgf/cm² = 98,066.5 Pa ≈ 0.968 standard atmospheres. The metric technical pressure unit used in pre-SI European and Japanese engineering for boilers, hydraulic cylinders, and compressed gas systems. A steam boiler at 10 at operates at 0.981 MPa; hydraulic presses are rated at 200-600 at. Still used parenthetically in old German and Japanese machinery manuals and standards (DIN 1301-3 legacy). Converts simply from kgf/cm²: 1 at ≡ 1 kgf/cm². 1 at = 98,066.5 Pa.
Quick Reference Table
| Centimeters of Water (cmH₂O) | Technical Atmospheres (at) |
|---|---|
| 1 cmH₂O | 0.001 at |
| 2 cmH₂O | 0.002 at |
| 5 cmH₂O | 0.005 at |
| 10 cmH₂O | 0.01 at |
| 25 cmH₂O | 0.025 at |
| 50 cmH₂O | 0.05 at |
| 100 cmH₂O | 0.1 at |