Not long ago, enriched air nitrox was something only cutting-edge technical divers used. Today, the Enriched Air Diver course is PADI’s most popular specialty course. Here’s what you need to know about earning an enriched air certification and the pros and cons of diving nitrox.

What is nitrox?

Humans are accustomed to breathing air that’s approximately 79% nitrogen and 21% oxygen. Technically, any mixture of nitrogen and oxygen is nitrox – that includes the air you’re breathing right now.

In the scuba realm, “nitrox” (also known as enriched air nitrox and EANx) typically describes breathing gas that is 32-36% oxygen. More oxygen means less nitrogen, and that has some nice benefits.

As you learned in the Open Water Diver course, nitrogen absorption is one of the things that puts limits on our ability to explore underwater by determining how long we can stay underwater and how deep we can go. On the other hand, enriched air nitrox allows you to:

  • Extend your bottom time (longer dive times)
  • Shorten surface intervals
  • Dive deeper on repetitive dives

Is an enriched air certification “worth it”? 

If you fancy staying down longer and getting back in the water sooner, then yes; getting nitrox certified is worth it. You can take more photos, wave to more turtles, and spend more time exploring.

Many divers wait too long to try nitrox. They don’t realise the benefits of an enriched air certification until they’re on holiday.

Imagine this scenario:

There you are, on the second day of your diving adventure. Your first dive was deep, below 30 metres/100 feet. After a relaxing surface interval, you’re eager for dive two – a wreck.

During the briefing, the divemaster reminds the divers who are diving on regular air to mind their no-stop time. On the dive, you are forced to turn back before the enriched air divers. You watch with envy as the nitrox divers swim the wreck, follow a stingray conga line, and discover buried treasure.

All jokes aside, if you plan to do a multi-day dive trip or a liveaboard, etc., do yourself a favour and get nitrox certified. Nitrox allows you to spend more time at depth compared to diving with air, which means you’ll get a lot more out of your diving holiday.

Even if you’re only making one dive, but it’s deeper than 15 metres/50 feet, there are still benefits to be gained.

Consider this:

  • If you plan a dive to 21 metres/70 feet on air, your maximum no-stop limit is 40 minutes
  • If you’re diving in 32% enriched air, the no-stop limit is 60 minutes (unless you use up the air in your tank before then)

What are the pros and cons of diving with enriched air?

If enriched air is so great, why doesn’t everyone use nitrox all the time? Good question, there are a few reasons:

  • Cost – Enriched air tank fills typically cost more than regular air fills
  • Depth limitations – The maximum depth limit for nitrox is different from air and depends on the blend (something you’ll learn as part of your nitrox certification)
  • Availability – Not every dive shop offers enriched air
  • Cylinder requirements – You need a dedicated cylinder for enriched air fills

Start Your Certification Online

Getting nitrox certified only takes a few hours. You can complete most of your nitrox training online from home. A short, in-person session with a PADI Instructor where you’ll practise analysing air (and a few other things,) is all it takes to finish up.

You may have heard that the specialty course is challenging and you have to use multiple dive tables – not anymore. PADI’s nitrox course was updated several years ago. Now you use a dive computer for almost everything.