Menu

Friction Loss CoefficientsComment on this pageEdit this page

IFSTA “Single Hoselines”

Pumping Apparatus Driver/Operator Handbook, 2nd edition

Assumes FL = C x (Q ÷ 100)² x (L ÷ 100)

Hose SizeCoefficient (C)
20mm booster 1741.0
25mm booster 238.0
32mm booster 127.0
38mm 38.0
45mm 24.6
50mm 12.7
65mm 3.17
70mm with 77mm couplings 2.36
77mm with 65mm couplings 1.27
77mm with 77mm couplings 1.06
90mm 0.53
100mm 0.305
115mm 0.167
125mm 0.138
150mm 0.083
StandpipesCoefficient (C)
100mm 0.600
125mm 0.202
150mm 0.083

Single Line (Fireground Coefficients)

These are friction loss coefficients that I had on a printed sheet of paper from a pump course I participated in several years ago. I don’t know where they came from. Based on the values I suspect that these assume L to be # of 30m sections. – Matt Adams

Hose SizeCoefficient
20mm booster 522
25mm booster 71
32mm booster 38
38mm booster 11
45mm with 38mm couplings 7
50mm 4
65mm 1
70mm with 77mm couplings 1.7
77mm with 65mm couplings 0.4
77mm with 77mm couplings 0.3
90mm 0.2
100mm 0.1
115mm 0.05
125mm 0.04
150mm 0.025

Siamesed Lines of Equal Length (Fireground Coefficients)

These are friction loss coefficients that I had on a printed sheet of paper from a pump course I participated in several years ago. I don’t know where they came from. Based on the values I suspect that these assume L to be # of 30m sections. – Matt Adams

Hose Size“C” @ 2 Lines“C” @ 3 Lines
65mm .250.111
70mm with 77mm couplings .177.079
77mm with 65mm couplings .095
77mm with 77mm couplings .079