Nitrox Diving

When I first heard the word “Nitrox”, I was nervous because it sounded dangerous and experimental. People who have done Nitrox diving were throwing phrases like 22% of this gas and 40% of that gas and I was thinking to myself, is it safe to be breathing all those gases? Underwater? And so far away from real air on the surface? Well, my fears were unfounded. It is nice to know that it is just a word to describe enriched air. And Nitrox diving has been around for a long time and has a track record for being safe if used correctly. Phew!

What is Nitrox or Enriched Air?

Enriched air, or Nitrox, is a combination of nitrogen and oxygen. You have been breathing these gases since you were born. The air that we breath in is comprised of about 21% oxygen and 79% nitrogen. The difference when we talk about Nitrox is that the percentage of oxygen is increased. This means that Nitrox mixture with percentages of oxygen greater than 21% are called Enriched Air Nitrox (EANx). There are 2 common standard EANx mixtures, Nitrox 32 (32% oxygen) and Nitrox 36 (36% oxygen), also sometimes referred to as Nitrox I and Nitrox II respectively.

Who Uses Nitrox?

Enriched Air Nitrox was first used as a diving gas as early as the late 19th Century, and has been used extensively for over 50 years by commercial organisations and the military. It has even been used in medicine as a therapeutic gas. Experienced divers have been taking advantage of Enriched Air Nitrox fo wreck and cave diving, mariculture, scientific diving and many other diving activities. More recently, Enriched Air Nitrox has been recognised by national and international scuba diving certification agencies as an alternative breathing gas for recreational diving.

Unfortunately, there have been some misinformation about the application of Enriched Air Nitrox. Many people think that it is only used by divers who are doing deep dives. The fact is, according to studies being done, the best depths are between 15 and 40 meters, which falls comfortably within the stipulated recreational depths.

The benefits of using Enriched Air Nitrox over the more common air tanks include:

• Enriched Air Nitrox when used with standard dive tables or computers, provides a safety factor giving between a 1.5 to 2 stop time advantage. This is ideal for divers who simply wish to augment their safety factor, and those who may not be at their peak physical fitness.
• It allows an increase in no-decompression bottom time limits.
• It reduces the potential for decompression sickness.
• It allows a reduction of decompression time where no-decompression limits are exceeded.
• A reduced fatigue after a dive, resulting in reduced sub-clinical decompression sickness.

What About Oxygen Toxicity I Hear About Associated with Using Nitrox?

As with any other fun activities, there are rules and guidelines that you should adhere to. When you take the Enriched Air Diver certification, you are thaught how to monitor your nitrogen uptake by using a set of dive tables. The greater the depth, the shorter the amount of allowable no-decompression time due to the nitrogen loading. The same principle applies to oxygen at depth. The greater the depth, the shorter the bottom time. Oxygen toxicity on any Enriched Air Nitrox mix including air, usually comes into play on longer than normal recreational dives.

As long as you follow the Enriched Air Nitrox dive tables, you should be well within the oxyen tolerance limits.

The Enriched Air Diver course will teach you how to safely use Enriched Air Nitrox for no-decompression recreational diving. The course, which takes 2 days to complete, will address the use of Enriched Air Nitrox with 22 to 40% oxygen, with special emphasis on the 32% and 36% mixtures.

If you are interested to be certified as a Nitrox Diving and Enriched Air Diver, send us an email. We can make recommendations for you to learn, either at Kota Kinabalu or on Mabul Island.