Ohio Fire Alarm Practice Test

The type of smoke detector that uses a projected beam for detection is known as a projected beam smoke detector. This device operates by sending a beam of light from a transmitter to a receiver. When smoke enters the path of the beam, it scatters the light, which is then detected by the receiver. This type of smoke detector is particularly useful in large open areas, where traditional spot-type detectors may not provide adequate coverage.

Projected beam smoke detectors are effective for early detection of smoke over considerable distances, typically in spaces like warehouses, auditoriums, or large atriums. Their design allows for a reliable response to smoke, making them a preferred choice in situations where traditional detectors might struggle due to the size or configuration of the space.

In contrast, ionization and photoelectric smoke detectors use different mechanisms: ionization detectors react to smoke by measuring changes in ion flow within the chamber, while photoelectric detectors use a light source and a sensor to detect smoke through light scattering, but not through a projected beam method. Heat detectors, on the other hand, are designed to respond to changes in temperature rather than smoke. Thus, the projected beam smoke detector is specifically distinguished by its method of detection using a beam of light.