Friction Loss Cheat Sheet

This table shows friction loss for 100 ft section of most common sized fire hose (.75" to 6"). In the table, find the GPM shown along the left (green) and the hose diameter shown along on the top. The table's intersection of the GPM & Diameter is the friction loss measured in PSI. Links at the top of each column go to detailed friction loss tables for each hose size.

Example: 100 ft of 1.75 inch fire hose with 150 GPM has 34.9 PSI friction loss.
200 ft of 1.75 inch fire hose with 150 GPM will be 34.9 PSI (times 2) friction loss. Or 69.8 PSI.
You can find the answerhighlighted in yellow(below) or visit the friction loss calculator.


GPM
Hose Diameter in Inches (100 ft hose length)
0.751.001.251.501.752.002.503.003.504.004.505.006.00
52.80.40.20.1
10111.50.80.20.20.1
1524.83.41.80.50.30.2
204463.210.60.30.1
2568.89.451.510.50.1
309913.57.22.21.40.70.20.1
401762412.83.82.51.30.30.10.1
5037.52063.920.50.20.10.1
605428.88.65.62.90.70.20.10.1
7073.539.211.87.63.910.30.20.1
809651.215.49.95.11.30.40.20.10.10.1
90121.564.819.412.66.51.60.50.30.20.10.1
100150802415.5820.70.30.20.10.10.1
125234.412537.524.212.53.11.10.50.30.20.10.1
1501805434.9184.51.50.80.50.20.20.1
17524573.547.524.56.12.110.60.30.20.2
20096623282.71.40.80.40.30.2
25015096.95012.54.22.11.30.60.50.3
300216139.572186.13.11.80.90.70.5
350294189.99824.58.34.22.51.210.6
4002481283210.85.43.21.61.30.8
45016240.513.76.94.121.61
5002005016.98.552.521.3
6002887224.412.27.23.62.91.8
7009833.216.79.84.93.92.5
80012843.321.812.86.45.13.2
90016254.827.516.28.16.54.1
100020067.734201085
1500152.376.54522.51811.3
2000270.813680403220

Friction Loss Explained

Friction loss occurs when water passes through a hose. Hose length, diameter, and GPM (volume) all affect friction loss. As water passes through a hose, friction between the water and the inside surface of the hose causes turbulence, which slows the water. The results in a PSI drop (pressure loss) at the other end of the hose. The higher the gpm passing through a hose, the more turbulance and friction loss will result.

Fire Engine Operator Tools


FireDepartment.net strives to provide fire departments & firefighters with quality tools. But, the user takes full responsiblity for the information contained above. Use at your own risk!