Proactive protection

A company has developed a fire protection system that actually works on the ‘prevention rather than cure’ principle. Rather than fighting fires with water sprinkler systems or extinguishing agents, Cambridge-based firm Wagner UK’s novel fire protection system ensures that fires do not take place – period. Wagner’s system, Oxyreduct, works on the principle that if you reduce the oxygen content of the air within an enclosed room or building, you will remove the possibility of a fire occurring. The system is not over-complicated either. Fresh air is compressed and then filtered, extracting the nitrogen. This produces air with a 95% nitrogen content, which is then piped at low pressure into the area to be protected. Room sensors then report back to the control system and enable the oxygen level to be maintained at the desired level, by regulating the nitrogen supply. There are some waste products generated. The compressor creates a small amount of water as part of the dehumidifying process and the nitrogen generator vents air with an enriched oxygen (30%) content. Wagner told Eureka that the nitrogen generator must be within 30m of the compressor but that “there is no limit, within reason, to how far the generator can be from the risk area.” As for piping, the nitrogen supply should be steel until it enters the risk area. From then on the pipe can be plastic as the pressure at the outlet in the room is negligible. A 3-phase power supply is all that’s required for the compressor and the nitrogen generator and control unit require a 240V supply. The system is now VdS approved and the only maintenance necessary is an annual change of the air filter and the membrane within the nitrogen generator needs replacing after 10 years! The system is automatically monitored for faults and is constructed to be failsafe. In the event of a fault occurring, protection to the area is not immediately lost – it can take days for the oxygen level to rise to a level where combustion can again occur, allowing time for repairs to be made. The area is therefore constantly protected and a fire cannot occur. Nitrogen is also an inert gas and is non-toxic in any quantity. And according to Wagner, the equipment size is not dependent on the volume of the room but on the leakage rate. It reckons a space saving is realised when compared to extinguishing systems, especially with larger volumes (>500m3). And existing HVAC systems have no effect on Oxyreduct. The natural ratio of oxygen to nitrogen remains the same at high level as it does at sea level. The amount of oxygen at high level is less because the overall air pressure is lower. The amount of oxygen users in an Oxyreduct environment would be breathing is similar to the amount of oxygen we would breathe in an aircraft cabin or up on a mountain. But the air pressure remains the same as the ambient level. At oxygen levels of 15%, Wagner advises users to inhabit the protected area for no more than six hours, after which they should take a 30 minute break. Glenn Grant, MD of Wagner UK commented: “The system requires a compressor, a nitrogen generator, control centre, a gas sampling detector, alarm and display equipment and a pyrolysis air sampling detector. Oxyreduct is also pretty cost effective because nitrogen is produced only when required and is not stored in pressurised containers.” He said the system, which was launched back in 1999, has already attracted much attention from major manufacturers, IT and telecoms companies. The likes of BASF Chemicals, Hugo Boss and Siemens simply love the idea that a system can protect their assets from fire 24/7. The system cost is almost not a concern when you think of the assets that are at stake. More than 40 Oxyreduct systems have already been installed across Europe. With IT and telecoms companies, constant availability is a must for today’s data and communication hubs. Downtimes of no more than 15 minutes per year are now being sought by these companies and so fire detection and extinguishing systems on their own are not enough. IT companies have to maintain communication channels, protect nodal network points and maintain constant availability and fast access for users and customers Having a good insurance policy against fires may be enough for some firms, but for others insurance cannot replace permanent damage to important documents, files or equipment. And many traditional fire extinguishing systems can actually cause damage to the very items they are supposed to be protecting. Early detection relies on the user being able to take swift action. There’s another fundamental drawback with fire extinguishing systems. You already have to have a fire, so it is a last line of defence. You cannot guarantee the system will extinguish fire or prevent re-ignition. The fire will also have had a good chance to grow before extinguishant is released so damage risk is high. False alarms are more frequent and can cause downtime and cost. And using extinguishants can mean you need to consider the costs of clean up, data loss, operating systems loss, time to repair building damage and time to replace hardware. Facts about fires in the UK * Two-thirds of all fires occur at times when buildings are closed (The Home Office) * There are 200 fires in the workplace every day (Fire Protection Association) * Fire and business interruption claims for commercial premises exceeded £2.6m per day in 2001 (Association of British Insurers) * 48% of all serious fires are arson related (Arson Prevention Bureau) Pointers * The system works by compressing fresh air then filtering and extracting the nitrogen, producing air with a 95% nitrogen content. This is then piped al low pressure into the protected area * The system is automatically monitored for faults. Room sensors report back to the control system and allow the oxygen level to be maintained at the desired level, by regulating the nitrogen supply * Possible applications include IT and telecommunications rooms, archives, vaults, plant rooms, deep freeze rooms, paper storage, high rack storage areas, switch rooms and composite panel buildings