Which feature in a sprinkler system is designed to allow firefighting teams to supplement the water supply and monitor system pressure?

• A. test the system
• B. connect hand lines for attacking the fire
• C. back up the first-attack units
• D. ensure that the pressure of the primary water supply is maintained

Answer: (D)

The key idea is a feature that lets firefighters add water to the sprinkler system and check system pressure from an external source. That feature is the Fire Department Connection (FDC). By connecting a pumper or another water source to the FDC, water can be supplied into the sprinkler/standpipe system, helping to maintain adequate pressure as water is drawn from the building’s supply. Gauges on the system allow monitoring of pressure while this external supply is being added.

The other options describe actions that don’t involve providing an external water supply or monitoring system pressure—testing the system, attacking the fire with hand lines, or simply backing up first-attack units.