Is Nitrox worth it? The pros and cons of EANx

by | Aug 7, 2023 | Diving, Diving advice, Uncategorized

What is Nitrox and should I get Nitrox certified?

Nitrox is diving shorthand for Enhanced Air NitrOx, also known as EANx, which is gas blended with a higher percentage of oxygen, relative to nitrogen, than normal air.

As recently as the 1990s, nitrox was the preserve of specialist and technical divers but it has ballooned in popularity and is now so mainstream that PADI’s Enriched Air Diver certification is the organisation’s most popular speciality course.

Why has diving on nitrox become so popular?

Simply put, when you dive on nitrox your body absorbs less nitrogen.

Normal air is composed of around 21% oxygen and 78% nitrogen, (plus a few trace gasses including carbon dioxide).

Standard EANx blends are 32% oxygen and 36% oxygen, which means there is less nitrogen.

Extended bottom time, longer repeat dives, shorter surface intervals, less exhaustion

The biggest advantage of nitrox is therefore an increase in a diver’s no decompression time.

A dive to 18m using air can be no longer than 56 minutes without a need for a deco stop.  But diving on EANx32 you can stay under for 95 minutes, and using EANx36 for a whopping 125 minutes – assuming you don’t run out of gas!

At 22m, the NDL increases from 37 minutes on air to 60 minutes on EANx32 and 70 minutes on EANx36.

So using nitrox means more time underwater.

Since you are taking on less nitrogen, it also means shorter surface intervals are required to off-gas the absorbed nitrogen, making nitrox particularly valuable for divers who wish to make multiple dives in a day.

This also means your second or third or fourth dive of the day can be longer, or to a deeper depth, than would be the case if you were diving on air.

So becoming nitrox certified means you are likely to get more out of your diving holiday,

Spend more time at deeper sites like the Alma Jane, right, by diving on Nitrox

Alma Jane - Puerto Galera

Additionally, divers often report that the drowsy and exhausted feeling which can come with making multiple dives in a day is reduced or even eradicated by using nitrox instead of air.

Maximum operating depth

One common misconception however is that using nitrox allows you to “dive deeper”: this is not the case. 

It does extend your bottom time, particularly at deeper recreational depths down to 30m – the deepest depth allowable by those who have completed the Advanced Open Water Course.

And it means repeat dives can be deeper than they’d be if you were diving air.

But as with all such activities it comes with risk, in this case the risk of oxygen toxicity, which can happen when the concentration of oxygen you are breathing becomes too great, as it would if you breathed EANx under the higher pressures which come at deeper depths.

So the maximum operating depth (MOD) for EANx32 for instance is 33m, and for EANx36 is 28m, to keep within conservative limits for oxygen toxicity. Always use your dive computer and follow conservative guidelines.

Nitrox dives also tend to cost a little more, because to fill your cylinder with EANx requires adding oxygen to the mix – so your dive shop either has to use more sophisticated expensive machinery to fill the tank, or buy large cylinders of medical oxygen to add to the air until the correct percentage mix is achieved.

We carefully control the inflow of O2 from our medical oxygen tanks
an oxygen analyzer tracks the percentage of O2 in the mix

Becoming EANx certified

Diving nitrox is nonetheless extremely safe and popular, for those who have taken the proper course to understand the science and to know what they are doing.

The PADI Nitrox course, available at LLV, is available to all divers over the age of 12 who are already at least Open Water certified. 

You’ll learn how to choose the right air blend for your dive, how to use a gas analyser to confirm the mix in your cylinder, and how to set your dive computer to the gas mix you are using so it gives you accurate NDL and MOD readings.

You will also benefit from learning more about the science of diving and diving physiology, great if you have any plans to go on to become a divemaster or scuba instructor one day.

The course can be completed without dives but there is an option to include two open water dives with one of our excellent PADI instructors, for extra practice.

What are you waiting for?

So get more out of your diving holiday, spend more time underwater, feel fresher and become a better-informed diving by getting your Nitrox certification at LLV.

Get in contact with us today to arrange to become a Nitrox diver. Click over to our Accommodation Page to book a stay, or our Diving page to look at the courses and prices we offer, and get in touch:  Phone: +63 917 570 3415    |    WhatsApp / WeChat / Viber: +63 917 570 3415    |    Email: info@lalagunavillas.com.ph    |    Go to our Contact Us page

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