Vesda Specialty Detection

The VESDA (Very Early Smoke Detection Apparatus) air sampling fire detection system detects the invisible by-products of materials as they degrade during the precombustion stages of an incipient fire. And, by actively and continuously sampling air, the system operates independently of air movements.

In operation air samples are continuously drawn from the monitored environment, typically through a sampling pipe network with the aid of a high efficiency aspirator. On the way to the fire detector the air samples pass through a filter assembly to screen out large airborne dust particles. Once inside the air sampling detector the samples are exposed to a high-intensity and broad-spectrum light source. The incident light scattered from smoke particles in the air sample passes through a series of optical components to a solid state light receiver. The light is converted to an electronic signal and passed to the control system.

At the control module the signal is processed and presented on an analog bar graph to visually indicate the level of smoke present in the monitored area. Depending upon smoke levels and the preprogrammed alarm levels, the appropriate output signals are generated.

The first of the three staged alarm levels (ALERT) may simply indicate that the system has detected something out of the ordinary that should be investigated. The second level (ACTION) indicates that a potential fire exists and that emergency procedures should begin. The third level (FIRE) signifies an actual fire condition.