Enriched Air Diving - the basics

Diving Nitrox (nitrogen & oxygen mixes)

"What is Nitrox diving exactly?" is a question that I pose to a few people. Generally divers say, - "it's what you use if you want to dive deep". Wrong! Sorry but that's not what Enriched Air scuba diving is all about.

Nitrox (Nitrogen - Oxygen mix) is about diving for a longer time (bottom time) not deeper diving. Let me give you an example.

The air that you and I are breathing now (as long as you are not reading this underwater!) is a basic mixture of 21% Oxygen and 79% Nitrogen. Nitrox is a mix of oxygen and Nitrogen that is not the usual air content. If you are to breathe normal air (with 79% Nitrogen) at a depth of 10 meters now you are breathing the equivalent of 158% Nitrogen (because now you are under 2 atmospheres of pressure, 1 from the surface and 1 atmosphere from the 10 meters of water pressure, hence twice the amount).  You can see now easily how the Nitrogen content builds up in our systems very quickly. Nitrox usually is a blend of gas where LESS Nitrogen is used and MORE Oxygen is used. 

As you know Nitrogen absorption is the main contributing factor of 'decompression sickness' or 'the bends', this is why we can only stay down for a limited period of time (No Decompression Limit (NDL)) like you learned in your 'Open Water Course'. 

Simply by reducing the amount of Nitrogen and increasing the amount of Oxygen in a blend allows you to stay down longer as you are absorbing less Nitrogen during the dive.

It is for longer diving (a longer NDL - time under water) not for deeper diving!

The Nitrox course is informative and fun. How many times have you done a dive to 25-30 meters, really enjoyed it but had to come up due to running out of 'safe' bottom time? Using a specific blend (Nitrox) of air will allow you to enjoy 'THAT DIVE' for a longer period safely.

The Hardeep shipwreck locally Pattaya (Samesan), Thailand, is a great example of this. The ship wreck lies in 26 meters of water. Check this out for a great example of how Nitrox can seriously improve your bottom time.

As you can see by the basic example you double (and some) your 'No Decompression Limit' and can enjoy that dive for longer. Hence why the Hardeep wreck is such a perfect training ground for this. You can even take your Wrecks diving specialty using Nitrox.

The academics for the Nitrox course are more involved than this simple explanation but at least now you understand why divers might like to 'mix blends'.

Please UNDERSTAND that as you remove one danger (Nitrogen) you add another (excess Oxygen) which is why this course should be learned correctly. This is a great fun course (as you get nice long dives) but the academic content is very serious! You are now entering the realm of technical diving.

Why PADI Enriched Air Diver?

Maximize your time with the upgraded PADI Enriched Air Diver course (Formerly Nitrox Diver Course). Enriched Air Diver saves you time by allowing you to:

How much more time can I be underwater?

For example, if you dive to15 metres/50 feet on air, your no decompression limit is 80 minutes. But, diving on EANx36 gets you 220 minutes of no decompression time - an increase of 140 minutes! It’s perfect for underwater photographers, wreck divers and anyone who wants to stay down longer.

What do I need to start?

All you need is your open water diver certification. (You must be 15 years of age or older).

What will I do?

You will learn preparation and diving procedures involved with enriched air diving.

How soon can I be diving on enriched air?

Just a mini workshop and a couple dives and you’ll be on your way.

What will I need?

You'll need your PADI Enriched Air Crew-Pak, which includes an Enriched Air 32 percent Table, Enriched Air 36 percent Table and Equivalent Air Depth/Oxygen Exposure Table.

Where can I go from here?
You can apply this Specialty course towards your Master Scuba Diver certification. You also need the PADI Enriched Diver certification if you intend to move into technical diving.

For PADI diving instructors: Mermaids have witnessed that the scuba diving industry prefers to take dive instructors on for scuba employment from the MSDT level and higher. Although it is possible to achieve diver jobs directly from an IDC (Instructor Development Course), dive center employers are more likely to offer a dive vacancy to a professional diver that has more experience. The MSDT scuba diving rating displays that the dive instructor has good experience teaching diving. The MSDT internship with PADI specialty diver courses can assist in your scuba career.