Which action is required when deploying a 5" supply line?

Calculating the necessary pressure is essential when deploying a 5" supply line because proper pressure management ensures that there is an adequate flow of water to the firefighting operation. The size of the supply line, along with its length and any potential pressure losses due to friction, must be accurately assessed to provide the required water flow at the nozzle or appliance. Ensuring the correct pressure allows for optimal performance of the firefighting efforts and helps prevent issues such as inadequate supply or excessive nozzle reaction.

While monitoring water flow and managing the discharge are important considerations, they are secondary actions that support the primary goal of ensuring sufficient pressure. Firefighter training is always vital, but the immediate context of deploying a supply line specifically underscores the importance of calculating the necessary pressure to operate effectively.