What must distinguish alarm, supervisory, and trouble signals in a fire protection system?

In a fire protection system, it is essential that alarm, supervisory, and trouble signals have distinct and different signals to ensure quick and accurate responses to different scenarios. This differentiation is crucial for safety and efficiency; for instance, an alarm signal alerts occupants to a fire, while a supervisory signal indicates system issues that may need attention, and a trouble signal points to faults or malfunctions in the system. Clear distinctions among these signals help firefighters and safety personnel to assess the situation rapidly and take appropriate actions based on the type of signal received.

While having audible signals or being monitored 24/7 are important aspects of a fire protection system, the clear differentiation between types of signals takes precedence in ensuring safety and effective communication during emergencies. Furthermore, transmitting signals to an approved supervising station pertains to the system's overall operation but does not address the critical need for unique signaling for different types of alerts.