This video is a brief explanation of the operations of a fire suppression system.
In its simplistic terms, a fire suppression system is the combination of a fire alarm system connected to a fire extinguisher.
The fire alarm section of the system detects the fire or smoke and then sends a signal to the fire extinguisher which automatically activates and puts the fire out.
Fire Suppression System Video
In this video, the area being protected is a small Comms Room and the fire suppression agent on this system is FM200.
To enable us to hear what I am saying during the video, we have removed the gongs of off the fire bells within the Comms Room and isolated the outputs to the main fire alarm panel.
Within the protected area is a series of smoke detectors, in a room this size, there are four on the ceiling and four in the floor void.
Fire Suppression Design Principles
The four detectors are divided into two separate zones; therefore, two detectors are in zone 1, and the remaining two detectors are in Zone 2.
The fire suppression system has a 1st and 2nd stage if one detector activates the bell sounds, red beacon flashes, informing the occupants that the system is now in stage 1 a signal is sent to the main house fire alarm system, and any room dampers will close. If a second detector were to operate in an alternative zone, this will put the system into stage 2.
As you can see at the engineer has removed the actuator from the cylinder, as we do not want a discharge while carrying out this test.
In stage two the electronic pulsing sounder begins, and a blue flashing beacon illuminates. When the system is in stage 2, the room is now ready for the gas discharge, and a 30-second countdown timing sequence begins before the fire suppression agent, in this case, FM200 will automatically discharge within the protected area.
In stage 2, all occupants should have left the room, and the door should be closed behind them.
At the front of the panel, you can see the timer countdown before the gas is discharged.
For this demonstration, we have removed the actuator from the cylinder, but to show you that the actuator has fired; we have placed a screw driver within the solenoid. During normal operation, the solenoid is energized and therefore will grip the screwdriver, however, once the fire suppression system has activated the solenoid, the magnetic force is released, and the screwdriver will drop to the floor.
Finally, there are two other elements to discuss. The first is the pressure relief damper, and the 2nd is the smoke extract.
Pressure Relief Damper for Fire Suppression Systems
The pressure relief damper is the white square unit on the wall. The unit is similar to a “cat flap” and is designed to open at a certain room pressure. This is required because during gas discharge, there can be enough force from the pressure generated by the discharge of the gas to damage the structure of the room. Another point to consider is when the smoke extract is operated, a negative pressure is generated, and you will see this when we operate the smoke extract system.
The round circular unit next to the pressure relief damper is the smoke extract. This unit is required to extract the discharged fire suppression agent in this case FM200 and any smoke that may be trapped within the protected area.
As we operate the smoke extract you will notice the pressure relief damper open.
This completes our overview of a fire suppression system, if you require assistance in the design, installation or maintenance of fire suppression systems why not contact our office on 020 8541 5646 or visit our website on www.firesystems.co.uk and complete our contact form.