What type of fire detection system utilizes sensors that react to the presence of smoke or heat?

The correct answer is that fire detection systems are categorized under initiating devices. These devices are specifically designed to detect the presence of a fire by monitoring indicators such as smoke or heat. When they sense these elements, they initiate the alarm process, alerting occupants and triggering the fire response protocols.

Initiating devices can include smoke detectors, heat detectors, and flame detectors, all of which play a critical role in the early detection of fire hazards. By ensuring timely responses to potential fires, initiating devices help mitigate risks and protect lives and property.

In contrast, notification appliances are used to alert people in the vicinity of a fire after it has been detected, such as alarms and strobe lights. Control units process the signals from initiating devices and manage the overall fire alarm system, while suppression systems actively extinguish or control fires once detected. Each of these categories serves a different function, emphasizing the importance of understanding their roles within fire protection systems.