Nitrox Certified
Got my PADI Nitrox certification today. For the J2EE inclined, it has nothing to do with the NitroX IDE from m7 (now BEA) but is related to the mixture of NITrogen and OXygen. As you know already quite well, the air we breath is made of roughly 78.05% nitrogen + 20.95% oxygen + 1% trace gases including; carbon dioxide, carbon monoxide and various inert gases – mainly argon. YMMV vary if you breath air in the Cairo traffic. (You’ll avoid too much carbon dioxyde in your tank when diving unless you want to kill yourself quickly).
So air technically is nitrox.
What is meant by nitrox in recreational diving is an hyperoxic mix, that is, it contains more than 21% oxygen. The term used for nitrox in the diving industry is enriched air, enriched air nitrox (EAN or EANx). The most often used blends are 32% (EANx32) and 36% (EANx36) of oxygen.
What’s the deal with diving nitrox rather than air ?
Enriched air reduces the level of absorbed nitrogen in your body tissues, so it translates by longer no decompression limits, shorter surface intervals, longer subsequent dives, etc…. You get the picture.
It does come at a price though. The maximum operating depth is shallower and the risk of acute/central nervous system oxygen toxicity is much greater. Compared to nitrogen narcosis (which is your primary concern when planning a dive with air as oxygen toxicity comes into the picture at around 66m while recreational diving is normally above 40m), the problem with oxygen is that you may get little or no warning of an attack and your chances of surviving one are remote.
But lets’ not get to dramatic, that should not happen with proper planning. If you intend to dive at 28m with EANx36, you must stick to it and not go to 45m because you saw a hammerhead shark. You’ll maybe see the shark but probably not come back to tell anyone about it.
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