Fire Suppression Systems Explained

Fire suppression systems are used across industry, in public places and shared accommodation including apartment blocks and hotels. While water still extinguished structural fires, an increasing number of chemicals and alternative agents are now needed to control and extinguish fired in specialist and industrious environment. Some types of building require systems by law, while other use a system suited to that particular environment.

There are four broad types of sprinkler system; wet, dry pre action and deluge. They are installed according to the uses and needs of the room or building, but the wet system is most widely used. They are triggered by a heat activated 'bulb' in the centre of the valve which releases the water flow if heated to a certain temperature.

Gas Fire Suppression (GFS) uses a range of gasses which cause reactions to extinguish the fire. For example inert gasses, react with oxygen removing it from the atmosphere and suffocating the flames. The use of Halon was restricted under the Clean Air Act in the early 1990s.

Both GFS and extinguishers fall under the umbrella term of wet and dry chemical agents. These are discharged in a number of ways, with each of the devices containing different agents, suited to different fires. It is critically important that the correct agent is used on the correct type of fire, for example carbon dioxide for coking oil and foam on combustible liquids.

Due to the extraordinary atmosphere on commercial aircraft, a process called hypoxic venting is used. This keeps oxygen levels high enough for humans to breathe unaided but too low for combustion to occur. Hypoxic venting only works in a completely sealed environment and works by replacing around %5 of the oxygen present in the atmosphere with inert gas.