Which statement about sprinkler system operation is true?

• A. The system discharges automatically without any valves or alarms
• B. The system includes only aboveground piping
• C. It includes a controlling valve and a device for actuating an alarm when the system is in operation
• D. It requires manual activation for any discharge

Answer: (C)

Sprinkler system operation is automatic in response to heat, but it isn’t a free-flow system without controls. A key part of how it works is having a controlling valve to isolate the water supply and a device that actuates an alarm when the system is in operation. The valve lets you shut the system off for maintenance or in an emergency, while the alarm device—such as a flow switch or alarm valve alarm—sends a signal to building occupants or a monitoring service to alert responders. This combination ensures the system can be managed safely and people are alerted when discharge begins.

The other statements don’t fit because: water discharge isn’t automatic with no valves or alarms—there are always means to control and monitor the system; piping isn’t restricted to aboveground—systems can include underground mains and risers; and discharge doesn’t require manual activation—sprinklers are designed to release water automatically when heat is detected.