Which statement accurately lists the three signals produced by a fire alarm system?

Which statement accurately lists the three signals produced by a fire alarm system?

• A. Alarm signal, trouble signal, and supervisory signal
• B. Alarm signal, maintenance signal, and trouble signal
• C. Alarm signal only
• D. All signals are optional

Answer: (A)

Fire alarm systems use three categories of signals to convey status and events: alarm, supervisory, and trouble. An alarm signal is generated when the system detects smoke, fire, or is manually activated, and it drives the building’s audible and visual alarms to alert occupants. A supervisory signal shows a condition that could affect protection—such as a sprinkler valve being closed or a monitored device out of position—indicating the system needs attention but not that there is an active fire. A trouble signal flags faults or failures within the system—like loss of power, wiring or device faults, or communication problems—that could prevent the system from operating properly and must be addressed. The option listing these three types is the correct one because these are the standard signaling categories used to communicate the system’s status. The other choices introduce nonstandard terms or omit essential signals, which doesn’t reflect how fire alarm signaling is designed to function.

Fire alarm systems use three categories of signals to convey status and events: alarm, supervisory, and trouble. An alarm signal is generated when the system detects smoke, fire, or is manually activated, and it drives the building’s audible and visual alarms to alert occupants. A supervisory signal shows a condition that could affect protection—such as a sprinkler valve being closed or a monitored device out of position—indicating the system needs attention but not that there is an active fire. A trouble signal flags faults or failures within the system—like loss of power, wiring or device faults, or communication problems—that could prevent the system from operating properly and must be addressed. The option listing these three types is the correct one because these are the standard signaling categories used to communicate the system’s status. The other choices introduce nonstandard terms or omit essential signals, which doesn’t reflect how fire alarm signaling is designed to function.