As datacentres become hotter and more dense with servers, a greater chance for fire exists. But there is equipment on the market that applies a well known method of halting fire: starving it of oxygen.
Only a few vendors are offering oxygen-deprivation systems, but interest in the technology is growing. It involves pumping air that has such a low oxygen content that a fire can't start in the datacentre.
Air is composed of about 21% oxygen, 78% nitrogen and 1% of other gases. Fire needs the oxygen to burn, and lower percentages of oxygen makes it more difficult or impossible for fire to start.
Wood stops burning when the oxygen content falls to 17% and plastic cables between 16 to 17%, said Frank Eickhorn, product manager for fire detection at Wagner Alarm and Security Systems GmbH.
Wagner makes electric compressors that use a special membrane to remove some of the oxygen from the outside air, a system the company calls OxyReduct. The excess oxygen is removed from the datacentre, and the remaining nitrogen-rich air is pumped inside the datacentre.
At 15% oxygen, it is safe for humans to enter. The lower oxygen content of the air is similar to being at an altitude of about 6,000 feet, Eickhorn said. He demonstrated with a lighter inside a sealed atrium Wagner has on display at Cebit. It won't light.
Fire poses a danger beyond the immediate equipment that burns. Burning plastic components combine with moisture in the air to create an acidic vapour that can damage other equipment away from the flames, said Dieter Lietz, manager for technical training and support. Smoke damage is just as costly for insurance companies as fire, Lietz said.
Wagner was reluctant to quote a cost for its systems, as pricing depends on the air-tightness of a datacentre and its size, among other factors. Wagner has sold about 200 systems, said Peter Clauss, Wagner sales director.
N2telligence GmbH, a start-up company based in Germany, has taken the oxygen-deprivation concept a step further by using a fuel cell. The fuel cell provides two functions: it can supply low-oxygen air to the datacentre and power during a sudden outage, said Lars Frahm, one of N2telligence's co-founders.