SSI EAN Nitrox Diver Specialty

Increase your no stop limit with Nitrox

Nitrox courseDuring the EAN Nitrox or Enriched Air Diver course, you will learn to conduct dives using Nitrox gas mixtures. Strictly speaking, any gas mixture of nitrogen and oxygen is considered a Nitrox gas. However in diver terminology, we usually use the term to describe gas mixtures with more than 21 % oxygen. Common gas mixtures are EANX32 (32 percent oxygen) and EANX36 (36 percent oxygen). What benefits do we get with Nitrox? First of all, the high percentage of oxygen itself doesn’t help anything. However, because a increased percentage of oxygen equals a decreased percentage of nitrogen, less nitrogen dissolves in our blood streams and tissues, thus reducing the risk of DCS (Decompression Sickness). So if we dive with EANx36 the nitrogen percentage is reduced from 79 % (air) to only 64 % nitrogen. Less nitrogen translates into longer no stop limits. Thus at 30 meter depth, we can only dive 20 min with normal air. However, if we use EANx36 we can stay 35 min, a much more reasonable no stop limit for a dive with a normal 12 liter tank. One common misconception is that with Nitrox you can go deeper. Oxygen in higher concentrations is a very toxic gas to our body. Thus if we use EANx36 we shouldn’t go deeper than about 34 meters (ppO: 1.6 bar), with EANx32 it’s 40 meters and even air bears a risk of oxygen toxicity below 60 meters (but in that depth, nitrogen narcosis would become a serious problem). So the higher the percentage of oxygen, the shallower we have to dive to avoid oxygen toxicity. Nitrox thus allows us to dive longer at a given depth, but NOT to go deeper. How to calculate the maximum operational depth (MOD) of a Nitrox mixture, how to analyze a given gas mixture and how to find out the no stop limits of a Nitrox gas, this all you will learn during the SSI EAN Nitrox course.

Minimum age: 10 year

Maximal group size: 8 participants
Course duration: 2 days, 1 day theory (doing it as a homework possible), 1 day on the boat.
Maximum depth: 12 – 40 m (depending on your dive level).

Course price: 6’000 baht (Pattaya).