Home Tech Tips Scuba Tech Tips: Nitrox – Good or Bad?

Scuba Tech Tips: Nitrox – Good or Bad?


Hi, guys. It’s Alec Peirce with Tech Tips and here we are discussing nitrox. There’s not too many divers who have not heard the word nitrox. Sometimes you hear it as a pleasant word – hey, nitrox! – and other times it’s almost a swear word – nitrox?! The point is that there’s a lot of misinformation, a lot of misconceptions, about nitrox, what it does, and what it doesn’t do.

The only way you’re going to really understand nitrox and whether or not it is a part of the sport you should look into, is to take a course. There’s no reason why not: you learn a lot in the enriched air course, get your certification card, and can try nitrox when you can. At the very least, now you understand what it is and what it is not.

You’ve probably seen tanks like this: enriched air nitrox, EANX. Basically, that’s what nitrox is: it’s enriched air. What do you mean by enriched air? Simple. It’s air with more oxygen than normal. As you probably know, the air we’re breathing right now, atmospheric air, is roughly 20 or 21 percent oxygen, and that’s what we live on. For a variety of reasons, when you’re scuba diving, it might be beneficial to have a higher percentage of oxygen: instead of 21 percent you might have 22, 23, 24, or 25 percent. Typically, nitrox divers choose a common mix, which is 28 percent oxygen; the most common mix is 32 percent.

It doesn’t greatly change your diving habits or how you actually dive. You don’t breathe deeper or differently and you have the same buoyancy: everything is exactly the same. As a matter of fact, if you ever do get the chance to try diving with a nitrox tank, you won’t even know. It doesn’t taste different and you don’t even notice you’re diving with a different mixture of air: it just so happens that air has more oxygen than normal.

So what are the benefits of nitrox? There’s several – and some disadvantages as well. One reason for using nitrox is to lessen the likelihood decompression sickness. The best way to avoid decompression sickness is to ensure you never go too deep and too long. If it so happens that you are diving on a particular dive profile where you might build up a high level of nitrogen, the use of nitrox may lessen the bends. Also, along the same line, there are certain people that are more susceptible to decompression sickness like old people (like me). If you have scar tissue, internet or external, it also increases your likelihood; fat tissue absorbs nitrogen faster than other tissues and if you are overweight, nitrox may be worthwhile.

What about disadvantages? First of all is the cost: the mixture costs money to make and therefore costs you money to buy. There may be some ancillary costs as well: you may have to get your equipment changed very slightly, generally cleaned; though most scuba equipment today is ready to go for nitrox (as much as 40 percent, which is fairly high). In some cases – because of the dive store, personal preferences or the charter you’re working with – they may want to have your equipment specialty cleaned if you’re going to use nitrox.

As far as your diving practices go, there’s a misconception that using nitrox allows you to go deeper and stay longer. No. Sorry. In fact, in many cases, it is the opposite: you may or may not be able to go deeper or stay longer. Take the training program so you can find out these differences.

I hope I’ve given you something to think about. Nitrox can be very beneficial, it can be costly, and it may not give you the advantages you think so. Take a few minutes, talk to your local dive store and ask if you should take an enriched air course. Take his advice and have a good time.

Be careful out there,