Smoke detectors are a key part of any comprehensive fire alarm system as smoke may be present before flames. The Federal Signal model FSF109 Two–wire Photoelectric Smoke Detector and the FSF110 Two–wire Ionization Smoke Detector are designed to provide notification at a UL Listed Fire Alarm Control Panel when smoke is present. Each unit provides a localized indication of stand–by and alarm conditions via a built in status L.E.D. The FSF109 and FSF110 Smoke Detectors include removable covers for easy cleaning, a local switch for field testing, and a sealed design to minimize dust and insect intrusion.

The Federal Signal model FSF109 Photoelectric detector is designed to detect smoke through its effects on light. This makes the device highly effective at detecting a smoldering fire long before it bursts into flames. Drift compensation and smoothing algorithms are standard to minimize false activation. The model FSF110 Ionization Smoke Detector reacts to the changes in ionized particles, making it better at detecting a flaming or quickly consuming fire. With this design, the FSF110 can detect smoke not visible to the naked eye. Both detectors are capable of detecting a fast–flaming fire, however for complete protection and notification, a heat detector, duct detector and an audible/visual alarm may be purchased separately.

Each FSF Smoke Detector incorporates a slim profile, designed to be unobtrusive and minimize potential overhead obstruction. The included mounting plate is designed to fit a 4 square junction box, 3 1/4 octagon box or plaster ring and adapts easily to uneven mounting surfaces.