Pressure Equivalents:
Pounds Per Square Inch (lb/in²) to (Head) Feet of Water (ft H2O)
| Conversion factor | ||||||||||
| 1 lb/in2 = 2.3089 ft H2O | ||||||||||
| (Water at 60° F) | ||||||||||
| Base Table | ||||||||||
| lb/in2 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Head: ft H2O | ||||||||||
| 0 | 0.0 | 2.3 | 4.6 | 6.9 | 9.2 | 11.5 | 13.9 | 16.2 | 18.5 | 20.8 |
| 10 | 23.1 | 25.4 | 27.7 | 30.0 | 32.3 | 34.6 | 36.9 | 39.3 | 41.6 | 43.9 |
| 20 | 46.2 | 48.5 | 50.8 | 53.1 | 55.4 | 57.7 | 60.0 | 62.3 | 64.6 | 67.0 |
| 30 | 69.3 | 71.6 | 73.9 | 76.2 | 78.5 | 80.8 | 83.1 | 85.4 | 87.7 | 90.0 |
| 40 | 92.4 | 94.7 | 97.0 | 99.3 | 101.6 | 103.9 | 106.2 | 108.5 | 110.8 | 113.1 |
| 50 | 115.4 | 117.8 | 120.1 | 122.4 | 124.7 | 127.0 | 129.3 | 131.6 | 133.9 | 136.2 |
| 60 | 138.5 | 140.8 | 143.2 | 145.5 | 147.8 | 150.1 | 152.4 | 154.7 | 157.0 | 159.3 |
| 70 | 161.6 | 163.9 | 166.2 | 168.5 | 170.9 | 173.2 | 175.5 | 177.8 | 180.1 | 182.4 |
| 80 | 184.7 | 187.0 | 189.3 | 191.6 | 193.9 | 196.3 | 198.6 | 200.9 | 203.2 | 205.5 |
| 90 | 207.8 | 210.1 | 212.4 | 214.7 | 217.0 | 219.3 | 221.7 | 224.0 | 226.3 | 228.6 |
| 100 | 230.9 | 233.2 | 235.5 | 237.8 | 240.1 | 242.4 | 244.7 | 247.1 | 249.4 | 251.7 |
| 110 | 254.0 | 256.3 | 258.6 | 260.9 | 263.2 | 265.5 | 267.8 | 270.1 | 272.5 | 274.8 |
| 120 | 277.1 | 279.4 | 281.7 | 284.0 | 286.3 | 288.6 | 290.9 | 293.2 | 295.5 | 297.8 |
| 130 | 300.2 | 302.5 | 304.8 | 307.1 | 309.4 | 311.7 | 314.0 | 316.3 | 318.6 | 320.9 |
| 140 | 323.3 | 325.6 | 327.9 | 330.2 | 332.5 | 334.8 | 337.1 | 339.4 | 341.7 | 344.0 |
| 150 | 346.3 | 348.6 | 351.0 | 353.3 | 355.6 | 357.9 | 360.2 | 362.5 | 364.8 | 367.1 |
| Supplemental Table | ||||||||||
| lb/in2 | 0.1 | 0.2 | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | |
| Head: ft H2O | 0.2 | 0.5 | 0.7 | 0.9 | 1.2 | 1.4 | 1.6 | 1.8 | 2.1 | |
