Convert Millimeters of Water to Petapascals
Convert Millimeters of Water (mmH₂O) to Petapascals (PPa) instantly and accurately.
Conversion Formula
PPa = mmH₂O × 9.806650000e-15
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 Petapascals
A petapascal (PPa) = 10¹⁵ Pa - pressures found in stellar interiors. The Sun's centre is ~25 PPa, sustained by radiation pressure from nuclear fusion balanced against gravity. White dwarf stars: ~10⁴ PPa (electron degeneracy). Neutron stars: ~10⁹-10¹⁰ PPa, where nuclear structure fails and neutrons drip from nuclei at ~4 × 10⁸ PPa (the neutron drip line). The hadron-quark phase transition in the densest neutron star cores is estimated at 10¹⁰-10¹² PPa. No laboratory experiment can approach petapascal pressures. 1 PPa = 10¹⁵ Pa.
Quick Reference Table
| Millimeters of Water (mmH₂O) | Petapascals (PPa) |
|---|---|
| 1 mmH₂O | 9.807 × 10-15 PPa |
| 2 mmH₂O | 1.961 × 10-14 PPa |
| 5 mmH₂O | 4.903 × 10-14 PPa |
| 10 mmH₂O | 9.807 × 10-14 PPa |
| 25 mmH₂O | 2.452 × 10-13 PPa |
| 50 mmH₂O | 4.903 × 10-13 PPa |
| 100 mmH₂O | 9.807 × 10-13 PPa |