Browse by Category

Ask Joe & Larry

Do I need special equipment to dive Nitrox?

Good question!! And the answer is No.. and Yes.

The answer depends on how much oxygen you have in your Nitrox mix. In all honesty, Nitrox was known as a "license to steal" by many dive shop owners because to so many people nitrox was voodoo gas and they didn't understand what was involved.

In a previous question on nitrox computers we addressed nitrox.. let's review quickly:

The air we are breathing is about 21% Oxygen, and 79% Nitrogen. Nitrox is simply a mix where we bump up the Oxygen a bit. Normally to 32% or 36% Oxygen. The benefit is that with less nitrogen in the mix, we can extend our bottom times, or shorten our surface intervals, and still absorb less nitrogen than the same dives on air. Also many nitrox divers report feeling better, and less fatigued when diving on Nitrox.

So what about special equipment? Well many dive shops used to mix Nitrox using a method know as "partial pressure blending". This basically consists of bleeding some pure oxygen into an empty scuba tank from a medical oxygen bottle. After we have some pure O2 in the tank.. maybe 350 psi, they fill up the rest of the tank with air. This gives us a mixture when we're done that is obviously higher in oxygen than our standard air. Depending on how much oxygen you put in the tank to begin, you can mix up a 32%, 37%, etc.

Ok, the problem lies in the fact that oxygen, under high pressure, can cause spontaneous combustion when it comes in contact with hydro-carbons. By using a membrane, or a continuous blended system, you can avoid the problems with the high pressure O2. Still, the tank is supposed to have a big sticker that says NITROX on it and then with a little sticker you put the mixture, plus some other info.

And in time, you probably will take a Nitrox class. Nitrox is getting more popular by the day, and when you realize the safety benefits, and the ease of diving Nitrox, you'll probably decide to use it yourself. When you do hit that point - you'd hate to have to start over buying another computer.

In fact in our shop, we encourage nitrox to the point where we give you a discount on your Nitrox course when you buy a Nitrox computer. In fact, depending on which unit you get, and what you get in your package - the class might even be free! (Call for details!) We want our customers to have access to all the education they can get concerning their gear.

So if you're contemplating a computer purchase, and think that just maybe, someday in the future, you might want to try Nitrox, there is no problem buying one now - and just use it as an air computer until you can get Nitrox certified.


If you would like to ask your own questions, you can learn how to do that on the Comments Page.

Or Click Here to view the Question Archive.