Beam Detectors

Optical Beam Detector is a device that uses a projected beam of light to detect smoke across large areas, typically as an indicator of fire. They are used to detect fires in buildings where standard point smoke detectors would either be uneconomical or restricted for use by the height of the building. Optical beam smoke detectors are often installed in warehouses as a cost-effective means of protecting large open spaces.

They are used in large open areas such as atria and auditoriums, instead of a spot-type within the unit: a wall-mounted unit emits a beam of infrared or ultraviolet light which is either received and processed by a separate device (Projected Beam Smoke Detector) or reflected to the receiver by a reflector (Reflective Beam Smoke Detector).

The photosensitive receiver monitors light produced by the transmitter under normal conditions. In the absence of smoke, light passes from the light transmitter to the receiver in a straight line. In a fire, when smoke falls within the path of the beam detector, some of the light is absorbed or scattered by the smoke particles. This creates a decrease in the received signal, leading to an increase in optical obscuration.


Typical Smoke Detector Obscuration can be concluded as below: 

Detector type Obscuration
Ionization Smoke Detector 2.6–5.0% obs/m
Photoelectric Smoke Detector 0.70–13.0% obs/m
Early Warning Smoke Detector 0.005–20.5% obs/m
Optical Beam Detector 0.06–6.41% obs/m

Applicable Notes

  • Beam Detectors incorporate more than one level of alarm.
  • Beam Detectors alarm sensitivities are configurable and can be programmed.
  • To specify the location and coverage of Beam Detectors, please refer to manufacturer’s instructions.

Our Services

SISICO is able to offer an extensive range of Beam Detectors to suit your specific environment from below mentioned companies: