Which device would typically trigger a supervisory signal in a monitored fire alarm system?

• A. A water supply valve in a monitored zone
• B. A smoke detector in a occupied space
• C. A manual pull station
• D. A heat detector in a kitchen

Answer: (A)

Supervisory signals alert that a monitored component or control condition—the thing that keeps the system ready to respond—needs attention. A water supply valve in a monitored zone is a classic example: the valve position is watched, and if the valve is not in the normal ready state (for instance, it’s closed or not fully open), the system sends a supervisory signal to tell responders that the water supply could be blocked and needs to be restored. This kind of signal isn’t about an active fire detection or occupant alarm; it’s about maintaining the integrity of the protection system itself.

The other options would more likely produce alarm signals: a smoke detector or a heat detector would indicate fire conditions when triggered, and a manual pull station activates an alarm when someone pulls it.