When the water supply can not provide a flow rate of 150% of the pumps capacity, a placard with the ______ shall be placed in the pump room.

When the water supply can not provide a flow rate of 150% of the pumps capacity, a placard with the ______ shall be placed in the pump room.

• A. Maximum suction pressure
• B. System pressure
• C. Flow rate
• D. Minimum suction pressure

Answer: (D)

The key idea is communicating the minimum suction condition required for the pump to operate properly. When the water supply can’t deliver 150% of the pump’s capacity, the suction side becomes the limiting factor, so it’s critical to warn operators of the lowest acceptable suction pressure. A placard stating the minimum suction pressure tells personnel the threshold that must be maintained at the pump suction to avoid cavitation and to keep the pump from losing capacity. This focuses on the suction condition directly affecting performance, which is why it’s the best choice. Other options don’t target the essential operating limit: system pressure is broader and can vary, maximum suction pressure isn’t the necessary baseline to ensure operation, and flow rate concerns the amount of water rather than the pressure needed to draw it reliably.

The key idea is communicating the minimum suction condition required for the pump to operate properly. When the water supply can’t deliver 150% of the pump’s capacity, the suction side becomes the limiting factor, so it’s critical to warn operators of the lowest acceptable suction pressure. A placard stating the minimum suction pressure tells personnel the threshold that must be maintained at the pump suction to avoid cavitation and to keep the pump from losing capacity. This focuses on the suction condition directly affecting performance, which is why it’s the best choice. Other options don’t target the essential operating limit: system pressure is broader and can vary, maximum suction pressure isn’t the necessary baseline to ensure operation, and flow rate concerns the amount of water rather than the pressure needed to draw it reliably.