Fire Safety Science Digital Archive

Measurements of pressure losses in fire hose and calculated friction factors are reported, and show significant differences between makes of hose. The value for friction factor of 0.005 given in the Manual of Firemanship for all diameters of non-percolating hose is found to be inappropriate for 19 mm hose reel hose and 89 mm hose. Based on the reported measurements, values for these hoses of 0.0065 and 0.007 are more realistic. The high value for 89 mm hose can be attributed to the reduction in diameter of the instantaneous couplings. Coupling losses are also found to be significant in 70 mm hose. Differences in hose wall construction give rise to large differences between different makes of 19 mm hose reel hose. Measurements of hose stretching under pressure are also reported.