Gas Suppression Systems.
The air that surrounds us every day contains around 21% Oxygen. Although not ideal, we are able to survive with a minimum of 12% Oxygen. Fire, however, requires a level of 15% or above in order for combustion to take place.
Gas suppression systems (also called clean agent fire suppression systems) extinguish fire by suppressing the oxygen levels in the atmosphere. This is done by the release of an inert gas or combination of gasses into the location. The gas suppression then reduces the chain reaction which causes combustion.
The system is activated by way of smoke detection which activates the release of a set volume of gas. These systems function in one of two ways known as “total flood” or “direct application”. Total flooding means that the entire area is filled with sufficient gas to reach a concentration high enough to reduce the percentage of oxygen in the air, bringing it down to below 15%. Fire is then no longer able to be sustained. Suitable warning must be issued and a delay is normally allowed before discharge for total flooding of CO2. This system can only be operated manually unless “Castell Locking” is employed. Direct application is centered on the likely base of ignition and CO2 is most commonly used for this application.
These systems are ideal for providing fire detection and safety in locations where using water or chemical agents would be inappropriate or damaging.
Good examples of appropriate locations are:
- IT server rooms
- Libraries and museums
- Art galleries
- Document archives
- Data vaults
- Telecomms switch rooms.
Aside from minimising damage, gas suppression systems also have a number of other benefits. They are a much safer means by which to extinguish an electrical fire as they are non-conductive. Some clean agent systems are more eco-friendly than tradition chemical methods.
It is important to recognise that BAFE operate a scheme called BAFE SP203-3 which covers fixed gaseous fire extinguishing systems. It is recommended that your system always meets or exceeds these standards.
In all total flooding solutions, integrity testing should be carried out to ensure the room can retain the gas for a minimum of 10 minutes.
With all inert gas systems, over pressure venting must be allowed. Thought must be given to the post discharge atmosphere, which should be vented to fresh air. This can be achieved in many ways, however over pressure vents are now available with extraction fans combined.
A further consideration is where gas cylinders will be stored. If is intended for storage to be above ground level, thought must be given to the loadbearing of the floor.
Like all fire detection and suppression systems, you have a legal obligation to have the system maintained and serviced every 6 months in order to ensure you are legally compliant.
Defensor is able to design, supply, install and maintain your gas suppression system, ensuring that it is legally compliant and meets with the highest standards recognised within the industry.
