_________ pressure is the difference between the pump discharge pressure and the incoming pressure from the hydrant.

• A. Maximum Discharge
• B. Residual
• C. Net Pump Discharge
• D. Pump Intake

Answer: (C)

Net pump discharge pressure is the difference between the pump discharge pressure and the hydrant’s incoming pressure. It shows the actual pressure available to the fire stream after accounting for what the pump is drawing from the hydrant. This matters because it reflects how much pressure the pump is adding to the water to reach the nozzle, guiding nozzle pressure selection and planning for friction losses along the hose lay. For example, if the discharge reads 120 psi and the hydrant intake provides 60 psi, the net pump discharge pressure is 60 psi. The other terms describe different concepts: maximum discharge pressure is simply a high discharge reading, residual pressure refers to remaining system pressure during flow, and pump intake is the water entering the pump, not the pressure difference.