What type of detector operates based on the presence of light and smoke particles?

The photoelectric smoke detector operates by detecting light that is scattered by smoke particles within its sensing chamber. This type of detector typically uses a light source, such as a light-emitting diode (LED), to illuminate the air inside the chamber. When smoke enters the chamber, particles scatter the light in different directions, and the detector's sensor picks up this light scatter. Once the light scattered by smoke particles reaches a certain threshold, the alarm is activated, alerting occupants to the presence of smoke and potentially indicating a fire hazard.

This method of detection is particularly effective for identifying smoldering fires that produce a lot of smoke before flames become prominent, making photoelectric detectors invaluable for early fire detection. Their sensitivity to smoke particles sets them apart from other types of detectors, as they specifically rely on the interaction between light and these particles for signaling the presence of smoke.