What is the primary difference between ionization and photoelectric smoke detectors?

Ionization smoke detectors are designed to respond more quickly to fast-burning, flaming fires due to their method of detection, which utilizes radioactive materials to ionize the air inside the sensing chamber. When smoke enters the chamber, it disrupts the ionization process, triggering the alarm. This type of smoke detector is particularly responsive to the small particles produced by flaming fires, making it effective in situations where such fires are the primary concern.

In contrast, photoelectric smoke detectors use a light source and a light sensor. When smoke enters the chamber, it scatters the light beam, which is then detected by the sensor, triggering the alarm. Photoelectric detectors are generally more effective at detecting smoldering fires, which produce larger particles and can be less intense at their onset compared to flaming fires.

Understanding this distinction is crucial in determining the best type of alarm for specific fire risks within an environment.