What is the purpose of a fire department connection on a sprinkler system?

The fire department connection (FDC) on a sprinkler system serves a critical role in providing an additional source of water during a fire emergency. Primarily, it allows firefighters to connect external hoses directly to the fire protection system. This feature is essential when the water supply from the building's internal system is insufficient to combat a fire effectively. By linking external hoses to the FDC, firefighters can augment the sprinkler system's ability to deliver water, ensuring that adequate pressure and flow are maintained to suppress the fire.

Using external connections can also be advantageous in situations where the sprinkler system's water supply may be compromised or in buildings with a particularly high demand for water during a fire incident. The design of the FDC ensures that it meets fire department standards and is readily accessible, enabling firefighters to react swiftly and efficiently in emergencies.

In contrast, the other choices do not accurately describe the primary function of an FDC. Increasing water pressure is primarily the job of pumps and not the FDC itself. Draining excess water or shutting off the water supply are functions related to different components of the fire protection system, such as drains or valves, rather than the FDC. Thus, the role of the fire department connection is specifically focused on facilitating an external water supply to