Diving with Nitrox

20 Feb 2020No Comments

Enriched air for diving

Since French engineers Jacques-Yves Cousteau and Emile Gagnan developed an underwater breathing system in 1943, humans have been able to learn about the wonders hidden in the seabed.

Every year more technology is presented at fairs around the world, improving the different types of diving, including sports, commercial or technical.

One of these technological improvements has a direct relationship to the gases we breathe. Atmospheric air is made of a 79% nitrogen and 21% oxygen ratio. Dive tanks are filled with this proportion of air, being equal to the air we breathe on the surface, so that we are not affected by gases or different proportions of air.

Enriched air for diving: Nitrox

A few years ago, a gas called nitrox or enriched air, was started to be used for sports and technical diving. This technique involves increasing the percentage of oxygen in the mixture and decreasing the nitrogen content in the dive tank. This change in percentages allows to significantly decrease the nitrogen saturation, and therefore, allows the diver to spend more time in the water.

It is important to know that nitrox does not reduce air consumption, as breathing is controlled by carbon dioxide and not by the level of oxygen.

The two most commonly used mixtures in nitrox are:

• 32% Oxygen and 68% Nitrogen.
• 36% Oxygen and 64% Nitrogen.

 Advantages of diving with nitrox tanks:

• To stay diving a longer time:
  The main advantage of nitrox diving is that it allows us more dive time without the need for decompression stops.
• Take successive dives within 24 hours:
  By making much shorter intervals, you can do more dives in less time.
• Nitrogen absorption is lower:
  In such a way that it will increase our well-being during and after the dive, and most importantly, significantly reduces the chances of getting a decompression disease.

Disadvantages of nitrox diving:

• Increased in the partial pressure of oxygen:
  When a person dives with nitrox, the risks of breathing oxygen thoroughly increases. Let’s remember that each gas exerts its own partial pressure. Oxygen gas has a toxic effect at partial pressures exceeding 1.4 pressure atmospheres, so depth limits must be, in particular, respected. Usually the maximum depths in which one can dive for each mixture of enriched air are lower than those of diving with normal air. This happens because since there is more oxygen the chances of poisoning by this gas increases.
• Oxygen is an oxidizing gas:
  When putting it in contact with some organic compounds, particularly some fats, it can generate a combustion reaction. For that reason, the valves and dive tanks used for nitrox must be compatible with oxygen. For safety, nitrox tanks are required to be marked for this use. Although each country has its own regulations, these dive tanks are usually light green and/or have a sticker that identifies them.

 Can nitrox be loaded with any compressor?

Definitely not. Air tanks can be loaded directly from the compressor or by cascades that stationary compressors possess.

With regard to nitrox loading, a mixer must be used in a compressor according to the desired percentage. Once the mixture is done. it should be analyzed with an oximeter: this reaffirms that the load is the right one.

After analyzing the mixture, it must be filtered, cooled, and dehumidified into two independent compressors. Finally, this mixture will pass through the loading ramp to finally be introduced into the tanks. Once the nitrox tanks are cold, the mixture should be re-analyzed in front of the customer to verify its proportion.

Let’s highlight that these compressors must have filters to remove carbon monoxide or dirt particles. Only in this way the air will be of good quality and safe to breathe. For this reason, we want to emphasize that the place where you buy, rent or load the dive tanks, must be certified, and comply with the regulations, so that the health of the divers will not get compromised.

To corroborate the proportion of gases, it is necessary to use an oxygen analyzer. It is an instrument that fits in the palm of the hand, is very accurate and of a profitable price. Its use is very simple, you hold it in front of the tank valve and open it a little bit until the reading is stable.

Nitrox Diving Course

To dive with nitrox it is mandatory to have the Nitrox Scuba Diver license.

In this course you will learn 3 basic things:

1. 1. To know the management of oxygen exposure.
   2. To practice the analysis of the oxygen content inside the dive tank.
   3. To set up your dive computer to dive with nitrox enriched air.

The Nitrox Scuba Diver course offers the options to do it with or without diving practices. No matter which option you decide to do, the license will be exactly the same.

If the nitrox is used properly, dives will be safer, under the presumption of course, that the air mix is correct and that the maintenance of the tanks is effective.

If you want more information or have any questions, contact us today.