What is the friction loss value for 44mm Hi-Combat?

• A. 50 kPa / length
• B. 200 kPa / length
• C. 75 kPa / length
• D. 100 kPa / length

Answer: (D)

Friction loss is the pressure drop caused by flow resistance along a hose, and it’s expressed as a pressure loss per unit length. For the 44 mm Hi-Combat hose, the standard value used in Edmonton practice is 100 kPa per length. That means for every unit length of hose, the water loses about 100 kPa of pressure due to friction. The total loss along a run is this rate multiplied by the hose length. The other numbers don’t match the published friction loss for this hose size under the standard conditions used in these exams.