What is the recommended minimum psi to maintain on the compound gauge when drawing water from a hydrant?

The recommended minimum pressure to maintain on the compound gauge when drawing water from a hydrant is 10 psi. This level is crucial as it ensures that there is adequate flow and pressure for the fire apparatus to operate effectively during firefighting operations. When the pressure drops below this threshold, it can indicate that water supply is insufficient or that the system is under strain, which may lead to reduced effectiveness in firefighting efforts.

Additionally, maintaining at least 10 psi helps in preventing issues such as cavitation, which can occur when the pressure drops too low, potentially damaging the pump and affecting performance. It creates a safety buffer that improves operational reliability and helps firefighters deliver the necessary water flow needed in emergency situations.