Residual pressure is the pressure remaining in the system while what occurs?

Residual pressure is the pressure remaining in the system while what occurs?

• A. Water is flowing from a hydrant or discharge
• B. No water is flowing
• C. The pump is off
• D. The tank is full

Answer: (A)

Residual pressure is the pressure that remains in the water system while water is actually moving through the mains and out a hydrant or discharge. As water flows, friction and other losses in pipes, fittings, and valves reduce pressure along the network. The reading you get at the point of measurement during that flow is the residual pressure. This is different from static pressure, which is the pressure when no water is flowing. So the condition described—while water is flowing from a hydrant or discharge—best defines residual pressure.

Residual pressure is the pressure that remains in the water system while water is actually moving through the mains and out a hydrant or discharge. As water flows, friction and other losses in pipes, fittings, and valves reduce pressure along the network. The reading you get at the point of measurement during that flow is the residual pressure. This is different from static pressure, which is the pressure when no water is flowing. So the condition described—while water is flowing from a hydrant or discharge—best defines residual pressure.