ADDRESSABLE ASPIRATING SMOKE DETECTION
Aspirating Smoke Detection (ASD) is an established smoke-detection technology. It involves a ventilator creating an airflow that draws air through the sampling points and detection module.
Originally developed as high-sensitivity smoke detection for computer rooms, its use has increased, and ASD now provides effective smoke detection where point smoke detectors might struggle or be deemed unsuitable, for example:
dirty, humid or cold atmospheres;
where conventional smoke detectors do not meet the aesthetic requirements of the building; and to provide safer maintenance procedures in hard-to-reach locations.
By using an ASD system, nuisance 'false' alarms, common in the above environments, can be avoided, without jeopardising the early warning provided by smoke detection.
Originally, ASD systems were expensive, making them cost-effective only where a large number of smoke detectors needed replacing. Advances in technology have allowed simpler and more cost-effective ASD systems to replace a few or even a single detector.
Previously, an ASD system could only provide general information relative to the sampling pipe.
But the next generation of ASD systems has the ability to detect the exact location of the fire. This makes it ideal for replacing detectors where a number of rooms are close to each other; such as offices, hotel rooms and suites, train compartments, server rooms, laboratories, switch cabinets, transformer rooms/ stations, prison/detention cells, apartments, hospital rooms and equipment cabinets.
Using a single pipe and some clever engineering, ASD works like a normal system, analysing air samples for fire. Should a fire be detected, it starts a process to determine the fire's location. This includes reversing the airflow in the pipe to clean it of smoke samples, then reverting back to normal airflow. It then analyses the air samples and works out which sampling hole is sensing fi re. This information is then displayed locally at the ASD and transmitted to the main fire panel.
As well as replicating a point detector's addressability, the system can also be monitored for faults. The biggest advantage is where access might be a problem. It is no longer necessary to enter a detention cell, hotel room or apartment to check a detector - maintenance can be performed outside the risk area and in a shorter amount of time.
Genesis Integrated Systems has installed some of these systems and has found that, in the right application, they are easily more cost-effective than point detectors over a system's lifecycle.