How Does A Smoke Detector Work?


By: Natalie Morgan

Fires are very dangerous and deadly events. One happens every minute of every day. Fortunately, fire can be  detected by a fire detector. Fire Detectors can save thousands of lives.


What’s Inside the Detector?

The fire-detection system today consists of an FACP (fire alarm control panel) – this is the system’s brain, and it’s capable of making rapid decisions.

  1. A length of the magic fiber (yellow) is stretched around a wheel (red) inside a metal container (gray) with holes at the bottom through which smoke can enter.
  2. The fiber is attached to a pivoting lever (light blue), held in place by a spring (purple).
  3. The blue lever holds another pivoting lever (green) in place.
  4. The green lever supports an electrical contact (dark blue) and holds it well above a second identical contact.
  5. The two contacts connect to a battery-powered bell or other electrical alarm circuit (not shown).


What Are the Types of Fire Detectors?

1. Ionization smoke detector

      2. Photo-electric smoke detector

      3. Projected beam smoke detector
      4. Aspirating smoke detector
      5. Video smoke detection
For more information on fire detectors, visit: