Relay operations is a pumping technique used to tackle insufficient fire ground water supply. Factors influencing the implementation of relay operations are grouped in phases like design, setup and shutdown of relay operations.
Use the dump line to allow water flow from source engine till the discharge of all the air from supply line and engage pump by adjusting throttle.
Continue to dump water through overboard discharge by setting the desired pressure for the pump and discharge water supply.
The operator opens bleeder valve in order to exhaust air in supply lines and relay water supply is established once the intake valve is opened. Overboard discharge is required to release excess pressure after shut down and pump throttle can be deployed for better supply.