What should be done before charging the aerial waterway for standpipe use?

Before charging the aerial waterway for standpipe use, it is crucial to shut down the master stream nozzle. This is necessary to prevent any premature discharge of water while the waterway is being pressurized. If the master stream nozzle is open during this process, it can create a safety hazard by causing an uncontrolled release of water, potentially putting personnel and equipment at risk.

Shutting down the master stream nozzle ensures that water does not flow until the system is fully charged and ready for use, allowing for controlled operations and maintaining the integrity of the firefighting equipment. This step is essential for ensuring that the aerial apparatus and attached standpipe system can deliver water effectively and safely to where it is needed once the system is prepared.

In this context, ensuring the proper procedure is followed is fundamental for safety and operational efficiency during firefighting activities.