The Benefits of Diving with Nitrox

The Benefits of Diving with Nitrox

July 19, 2019Divingdiving with nitroxguidesNitrox3670Views42Comments

Human beings clearly cannot breathe underwaterwhich is why you should have a scuba tank with you during your dives. These tanks usually contain regular filtered air, trimix, or nitrox. Divers typically use nitrox air in their tanks if they want to spend more time underwater. But what exactly is nitrox and how does it help you while you’re diving?

What is Nitrox?

rows of nitrox tanks on a dock

Nitrox is just what it sounds like: nitrogen mixed with oxygen. It’s also known as Enriched Air Nitrox (EANx) due to its increased oxygen percentage. This specific element sets it apart from other common diving gases.

Both recreational and technical divers use this breathing gas. In recreational diving, this breathing gas helps you absorb less nitrogen since it has more oxygen. Nitrox mixes usually contain more than 21% oxygen, but should not go above 40%.

Technical diving uses two nitrox-based mixtures: Nitrox I and Nitrox II. Both mixes combine pure oxygen and air. Nitrox I contains 32% of this combination, while Nitrox II has 36%. They also contain 68% and 64% of nitrogen, respectively. 

But what are the advantages of using nitrox over regular air?

What are the Benefits of Nitrox Diving?

close-up of nitrox tanks

So why should you dive with nitrox? There are a few substantial advantages, which include the following:

Longer Bottom Times

Divers who use nitrox absorb less nitrogen, making them stay underwater for longer. They’re also less likely to get decompression sickness. It’s worth noting that older divers and those who’ve experienced decompression sickness or physical injuries can reduce no-decompression limits with the gas. It can even give you twice as much diving time at 50 to 100 feet in some cases.

But if you’re using a nitrox tank while diving, you shouldn’t go over your maximum depth or bottom time. You should also look at your depth gauge closely during dives. If you have a dive computer, setting a depth alarm is essential for nitrox diving. This alarm will warn you immediately if you’ve gone over your maximum depth.

Less Fatigue

Research hasn’t justified this advantage yet, but there are divers who report less fatigue with nitrox. But many divers believe that less nitrogen means fewer micro-bubbles in a diver’s bloodstream and less decompression stress. It can also make you less tired and drained after diving.

Longer Dive Times

Dives on air always have pretty short repetitive dive times, which is disappointing for divers who dive in exciting environments that beg to be explored. But absorbing less nitrogen on your first dive with nitrox gives you more repetitive dive times. You’ll also get around five more minutes at 70 feet when you use the gas. It may not seem like much, but those extra five minutes can be precious, depending on your dive.

Shorter Surface Intervals

Breathing nitrox also gives you shorter surface intervals. This is a great advantage, especially if you want to dive again. You’ll have less nitrogen to get rid of, which can make a remarkable difference in the time it takes to de-gas on the surface. But if you don’t want to put yourself or your dive buddy at risk, you should look at the correct times for surface intervals on dive tables before the actual dive.

What are the Disadvantages of Diving with Nitrox?

diver handling a nitrox tank

Despite its pros, nitrox diving also comes with some disadvantages and potential dangers. Understanding these risks is just as vital as getting the right training in using diving gear so you can enjoy a safe and fun dive underwater. Here are some cons you should consider before diving with nitrox.

Not Suitable for Deep Diving

Before you can use nitrox in scuba diving, you’ll need to go through special training and learn certain procedures in handling this gas. One misconception divers have about these key elements is that they will help in deep diving. But deeper depths will make nitrox poisonous.

Oxygen Toxicity

Increased concentrations of oxygen can cause oxygen toxicity. Using nitrox in recreational diving can put you at risk for this condition. So before you dive with the gas, you should think about your oxygen limit. This factor covers your lungs’ exposure to oxygen and how long they should take it in while you’re underwater.

Acute oxygen toxicity comes with different symptoms, including distorted vision and convulsions. A nitrox diver with convulsions can drown and eventually die from it. By keeping a close eye on your maximum depth and total oxygen exposure, you won’t experience oxygen toxicity.

Diving Nitrox vs Air: Which Gas Should You Use?

We’ve covered the different pros and cons of nitrox diving, but there are two more factors you should consider when using this gas: cost and availability. Nitrox diving typically costs more than regular diving with filtered air for two reasons:

  • Trained divers and dive shop personnel use special procedures and gear in producing the gas.
  • Pure oxygen comes at a relatively expensive price.

You’ll also rarely see nitrox in most dive shops and destinations, even as it gets much more popular with recreational divers. And of course, scuba tanks still use compressed air for non-technical diving.

Getting Nitrox Certification

Nitrox diving can put you in danger while you’re underwater. This is why you should undergo special training for it. Proper training will help you understand how deep you can go with nitrox. And just like learning about diving gear and how you should use them, you’ll have a safer and greater diving experience when you know how to use the gas properly.

You can learn the following skills in an Enriched Air Nitrox course:

  • Determining your oxygen exposure
  • Analyzing your tank’s nitrox capacity
  • Using special air tables and gear for producing enriched air
  • Placing the right markings on your diving equipment
  • Filling up your tank with the gas
  • Programming your dive computer for nitrox diving

Many Open Water-certified divers eventually take an Enriched Air Diver Certification or nitrox certification course. PADI, TDI, and other scuba certification organizations offer EANx courses to aspiring nitrox divers.


  1. no see the benefits at all. instructor since 1996, had to teach/use nitrox on live aboard in 1999. u got 55 min at 60ft with air, most divers cant last that long anyway, and u cant go deep with nitrox. never felt any difference with nitrox vs air, get in shape people! 😉 big hype, big expense (for compressor) big hassling checking each tank

  2. The first time I realized the benefit of nitrox, was in Yap. Three of us in our group used nitrox for a “manta dive” and the rest were on air. After descending to 60 feet to wait for the mantas, the 3 of us on nitrox waved goodbye to the other divers after 20 minutes and we were able to continue watching the mantas dance around us for another 20 minutes before we ran out of bottom time!! It was amazing! Firm believer in nitrox!

  3. It’s my preference to dive nitrox. I usually keep EAN30 in my HP130s. For those who say it’s voodoo gas, I think not. I’m sold on nitrox and will continue to do so whenever possible. I find that I have more energy after a dive with nitrox. It breathes the same to me, but I feel a lot better afterwards.

  4. Most people that dive Nitrox do not understand the gas, or how to dive it properly, its further evidenced by some of these comments. The risks of a partially educated Nitrox diver far outweigh the benefits. Can you calculate PPO2 on the fly, or at least explain the relationship of PPO2 to atmospheric pressure? On that same note, what is a “safe” PPO2? Do you know what CNS is and why its important to track? What are the dangers of diving a high PPO2? If you cannot quickly answer all the above yes, then you are better off diving air until you can. There have been too many Oxygen Toxicity incidents in the last year in my opinion and I feel the dive community needs to be educated much better than it is at present. Nitrox certs are bolted onto AOW as an afterthought these days, and I become concerned that the emphasis on Nitrox safety is just not there.

  5. For me Nitrox is the only way to dive. Using standard air fills make me extremely nauseous with a ringing headache by the end of a diving day; with Nitrox I have no such issues. I called DAN and consulted them about such issues and they were of little help here. I am extremely conservative with my dives…don’t like going deep at all. Generally speaking I am happy with 60-80 fsw or less which is well within the limits of 32%. I do think that certain training agencies make it far too easy to obtain a Nitrox C-card however.

  6. after two dives on nitrox I feel great not tired and my dives are longer. chad don’t put air in tires put nitrogen in instead.30% more tire life and better mpg…guaranteed!

  7. Diving with a conservative PPO and staying within the limits of my air-integrated computer has extended my bottom time, lowered my nitrogen loading and is an absolute must for trips that involve multiple dives and multiple days.

  8. I agree totally. My wife and I get 55min at 60 ft and longer derpending on conditions. I’m 61 and been diving since I was 22. Other divers we have been with using Nitrox or air don’t last that long. I find divers really don’t know the con’s of Nitrox. How many dive incidents have been recorded from Nitrox use compared to air.

  9. The first paragraph in the article is messed up. While the ratio of gasses is changed there is still more Nitrogen than Oxygen in enriched air. Oxygen is a very thin gas and is off gassed easily. Feeling better after a dive on Nitrox is a placebo effect.

    1. While here are many flaws in the entire article – please don’t make it worse with additional errors – Nitrogen and Oxygen are side by side on the periodic table – oxygen is not a substanially “thinner” gas than nitrogen, whereas helium is a much thinner gas. If fact thinner gases can decrease no-decompression limits (and increase decompression obligations) in many cases – because thinner gases are absorbed into tissues faster (Henry’s Law). Nitrogen ( and helium ) are inert gases what goes into the tissue must come back out. Oxygen is metabolised, it It is generally agreed among diving specialists that oxygen usually need not be considered in questions about decompression when the inspired PO2 is within safe limits for CNS oxygen toxicity.

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