Convert Torr to Feet of Water
Convert Torr (Torr) to Feet of Water (ftH₂O) instantly and accurately.
Conversion Formula
ftH₂O = Torr × 0.0446033401
About Torr
The torr is defined as exactly 1/760 of a standard atmosphere ≈ 133.322 Pa - effectively replacing mmHg with an exact definition. Named after Evangelista Torricelli (1608-1647), inventor of the barometer. Vacuum science universally uses torr: rough vacuum 760-1 torr; medium vacuum 1-10⁻³ torr; high vacuum 10⁻³-10⁻⁷ torr; ultra-high vacuum below 10⁻⁹ torr. UHV systems for surface science, particle accelerator beam tubes, and space simulation chambers reach 10⁻¹¹-10⁻¹² torr. 1 torr = 133.322 Pa.
About Feet of Water
One foot of water column (ftH₂O) ≈ 2,989 Pa - the US customary equivalent of cmH₂O used in civil and hydraulic engineering. Municipal water supply systems are designed for 40-80 psi head ≈ 92-184 ft; fire suppression sprinkler systems require minimum 7 psi ≈ 16 ft. Well pump specifications, sump pump head ratings, irrigation mainline pressure, and drainage calculations all use feet of head. 1 ft of water = 12 in WC = 0.4335 psi ≈ 2,989 Pa.
Quick Reference Table
| Torr (Torr) | Feet of Water (ftH₂O) |
|---|---|
| 1 Torr | 0.0446033 ftH₂O |
| 2 Torr | 0.0892067 ftH₂O |
| 5 Torr | 0.223017 ftH₂O |
| 10 Torr | 0.446033 ftH₂O |
| 25 Torr | 1.11508 ftH₂O |
| 50 Torr | 2.23017 ftH₂O |
| 100 Torr | 4.46033 ftH₂O |