The PADI Enriched Air (Nitrox) Diver Specialty course is the most popular PADI Specialty course for certified divers. From the age of 12, divers with a minimum certification level of PADI Open Water Diver can take this course. You’ll learn all about the benefits of breathing oxygen-enriched air, as well as how to do so safely. And, the course can be completed in just a few hours!

Read on to learn about diving with enriched air, and the six top reasons why this should be your next specialty.


Two enriched air scuba diving cylinders - the most common mixes are 32% and 36% nitrox

What is Enriched Air Nitrox?

In recreational diving terms, enriched air (also known as nitrox or EANx) is breathing gas that contains a higher percentage of oxygen than regular air. Advantages of nitrox diving include staying at depth longer and shorter surface intervals.


Three Must-Know Terms

As an Open Water Diver, you’re trained to breathe air from a scuba cylinder. However, different rules apply for enriched air nitrox. This is due to the way the higher percentage of oxygen impacts our bodies at depth. Because of this, there are extra considerations and terms associated with nitrox diving, and that’s why it’s essential to get proper training before diving on enriched air nitrox. Here are a few examples of the additional vocabulary you’ll pick up during the course:

Mix: The percentage of oxygen. Regular air is 21%, and the most common enriched air nitrox mixes are 32% and 36%.

Maximum Operating Depth (MOD): The maximum depth at which to use any given mix to avoid oxygen toxicity, and why Nitrox divers should choose the optimum mix for the depth they plan to dive.

Analyzing: Enriched air divers need to know what mix they have in their cylinder in order to determine their MOD. They’ll use an oxygen analyzer to check the percentage of oxygen in the cylinder before diving.


A PADI Instructor explaining the benefits of breathing oxygen enriched air to students on the popular PADI Specialty course

Reasons the PADI Enriched Air (Nitrox) Diver Specialty Should Be Your Next Course

The Enriched Air (Nitrox) Diver Specialty course is the most popular PADI Specialty for a reason. The ability to dive with enriched air provides you added flexibility when deciding the best mix for the dive at hand. Read on to learn more about how nitrox can benefit your dives.

1. Breathe Less Nitrogen When Using Enriched Air

The primary benefit of using nitrox while diving is that you will be exposed to less nitrogen when you go diving. Put simply, the higher percentage of oxygen in the cylinder means you will be breathing less nitrogen.

You can use this benefit to your advantage in a couple of ways. One option is to extend your no-stop time during your dives, so you get to stay at depth longer, especially when completing repetitive dives. Alternatively, you might prefer to continue to dive within the no-stop limits for air but use the reduced intake of nitrogen to increase your personal safety margin while diving.

purpose of scuba diving

2. Longer Bottom Times

Typically, when using enriched air, divers will get mixes that are either 32% or 36% oxygen. This makes it ideal for diving at shallower depths.

For example, when diving with air to 18m (59ft) using the Recreational Dive Planner, you would have a maximum no stop limit of 56 minutes on a single dive. For the same depth, but using a 32% mix of enriched air (EANx32), you would have a no stop limit of 95 minutes. This means you would potentially have up to an additional 39 minutes of dive time on this profile compared with air. However, you should never forget to check your gauges. You will still be breathing through the gas in your cylinder at the same rate, so your total bottom time may still be limited by your gas consumption rather than your NDL (No Decompression Limit).

3. Shorter Surface Intervals

Another benefit of diving with nitrox is that because you have onboarded less nitrogen during your dive, you don’t need to spend so long off-gassing between dives. Hello to shorter surface intervals – less time on the boat and more time underwater!

A dive computer that features a compatible mode for nitrox diving, a useful tool for planning nitrox dives

4. Learn About Your Dive Computer

On the PADI Enriched Air (Nitrox) Diver Specialty course, you can learn about planning nitrox dives using dive tables or your dive computer. Most divers these days will use a dive computer when planning their dives. Fortunately, most dive computers are compatible for use with enriched air. If you are thinking about purchasing your first dive computer, you might wish to speak with your dive center about the possibility of completing the PADI Enriched Air (Nitrox) Diver course at the same time. This will enhance your understanding of how your computer works.

Some dive computers have a nitrox setting built into them. These come in two versions, either the dive computer will have a selection of preset mixes you can choose from, or you will need to enter the mix yourself. The computer subsequently determines the maximum depth and dive time based on the mix you’re using. It’s important to remember that if your computer has presets and your mix doesn’t match any of them exactly, the general advice is to always err on the side of caution and round up, not down, especially for deeper dives.

Two divers enjoying a scuba vacation and making use of the advantages of nitrox when doing multiple dives over several days

5. Work Towards Further Qualifications

If you have ambitions to become a PADI Divemaster one day, completing the PADI Enriched Air (Nitrox) Diver course will help develop your understanding of decompression theory and physiology. The great news is that you can take the PADI Enriched Air (Nitrox) Diver course alongside any other PADI certification. Find out more about which other PADI Specialty Diver courses buddy up well.

6. Enhance Your Holidays

The divers who enjoy the biggest benefits of diving with nitrox are those who like to take diving holidays. If you are taking a vacation locally or planning to book a dive resort or liveaboard, you may expect to complete a lot of repetitive dives over several days. If you are using enriched air to extend your bottom time, this could equate to hours of additional dive time over the holiday. Imagine how many more critters you might see!


The PADI Enriched Air (Nitrox) Diver Specialty Course

The PADI Enriched Air Diver course teaches everything you need to know about enriched air diving. First, you’ll learn how to select the right mix for your dive. You’ll also learn how to use an oxygen analyzer and how to set your dive computer. You can choose to study using eLearning followed by an in-person workshop at a PADI Dive Shop, or complete the entire course at your local dive center. The course can be completed dry and without dives, but many dive centers will include two open water dives conducted by a PADI Instructor for extra practice.

If you’re ready to experience the benefits of diving with enriched air nitrox versus air, then sign up for the PADI Enriched Air (Nitrox) Diver Specialty course today by clicking the button below. Visit the PADI eLearning page or contact your nearest PADI Dive Shop for more details.


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Originally written by Emily Petley-Jones

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