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Data Centers Breathe Easier With Less Oxygen
PC World is reporting that some companies are looking at a new method of fire protection in their server closets, oxygen-deprivation systems.""Wood stops burning when the oxygen content falls to 17 percent and plastic cables between 16 to 17 percent, said Frank Eickhorn, product manager for fire detection at Wagner Alarm and Security Systems GmbH in Hanover, Germany. 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 exhausted, and the remaining nitrogen-rich air is pumped inside the data center."
No, at 6000 feet there is still the same percentage of oxygen in the air, but at a lower pressure. This removes oxygen from the air. For a same volume of space it would have as much oxygen as a similar volume at 6000 feet.
Something will burn with the lower concentration of oxygen, but would be much less likely to ignite into open flame. It'd smolder slowly, and give you much more time to react to it.
It's a confusing analogy to explain a simple technical concept, because tech writers assume everybody is beneath their intelligence. Like putting too much air in a balloon.
I don't need no instructions to know how to rock!!!!
A few decades ago I served on a submarine. The oxygen generator stopped working for a while, and for operational reasons we couldn't snorkel for fresh air. The percentage of oxygen dropped below the point where combustion is supported, so the smokers were out of luck. People's lungs respond to the partial pressure of oxygen in air, not the absolute percentage, so the crew including myself were fine, since we were only at about the equivalent of 10,000 feet (US units). I always wondered wouldn't it be safer from a fire prevention standpoint to always operate like that.
People cook out up in Estes Park at 9-13K all the time. Maybe dude needs to refill his lighter...
It isn't just the partial pressure of oxygen that's important for fire. It's also the partial pressure of nitrogen. Nitrogen cools the reaction without contributing to it.
So having the partial pressure of oxygen appropriate to 6,000 feet while having even greater than sea-level partial pressure of nitrogen could well keep a fire from burning (at least in some fuels) and make it much harder than usual to get one started even in things (like magnesium) that would be happy to burn in this atmosphere (or even in pure nitrogen).
Meanwhile the human body is mostly interested in the partial pressure of oxygen and carbon dioxide. Walking into the data center would be like suddenly going from local altitude to 6,000 feet (minus the ear-pops and potential for a case of pressure-related issues). You'd run a little less "brightly" than usual. Live in such conditions 24/7 for a month or so and you'll build up additional hemoglobin in your blood until (like people who live at altitude) you're just fine. (I don't know if you'll get back to "full power" living in them 8/5, though.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Your lungs are mostly worried about the partial pressure of oxygen; .16 bars is what you need. Your lungs don't care too much if that's .16 bars of 100% oxygen, or one bar of 16% oxygen, or two bars of 8% oxygen. The level of concentration of oxygen doesn't matter too much, just the pressure of oxygen to drive membrane gas exchange.
.16 bars.
Fires, however, do not have gas-exchange membranes like your lungs, making the partial pressure less important, and the concentration more so. 8% oxygen at two bars is less supportive of fires than 100% oxygen at