Pumpers should generally maintain what pressure at the FDC unless placards indicate otherwise?

• A. 150 psi
• B. 100 psi
• C. 200 psi
• D. 75 psi

Answer: (A)

When a pumper is receiving water through the FDC, you want to provide enough incoming pressure to overcome losses in the supply hose and fittings and still allow the pump to develop the required discharge pressures for the attack lines. A target of about 150 psi at the FDC is the standard because it offers a comfortable head to account for friction losses and elevation changes, giving reliable nozzle pressures once the system is flowing. If placards or the incident water supply specify a different pressure, those instructions take precedence.

Choosing a much lower pressure would leave little margin for friction losses and could result in insufficient nozzle pressure, while a much higher pressure is unnecessary and can strain hoses and equipment.