Nitrox goes by several names. Sometimes you will hear it called Enriched Air. Sometimes EANx or even “SafeAir”. Nitrox is technically a slang term, however the dive industry has pretty much adopted it as an industry standard when asking for a recreational air mixture containing more oxygen than normal breathable air.
The air we breathe is actually an approximate mixture of 21% Oxygen and 79% Nitrogen. Nitrox is a mixture of nitrogen and oxygen. In recreational scuba diving, nitrox is usually a mixture of 22- 40% oxygen and 60-78% nitrogen. A particular mixture of nitrox is referred to by the percentage of oxygen in the mixture. Therefore, two common nitrox mixtures, Nitrox 32 (NOAA Nitrox I) and Nitrox 36 (NOAA Nitrox II), contain 32% and 36% oxygen respectively. Air, which contains only trace amounts of gases other than nitrogen and oxygen, can be considered Nitrox 21 as it contains approximately 21% oxygen. The terms “enriched air” and “nitrox” are sometimes used interchangeably, but they are not the same. “Nitrox” refers to any mixture of nitrogen and oxygen, while “enriched air” refers to mixtures of oxygen and nitrogen that contain more than 21% oxygen. Special training and certification are required to dive with nitrox.
Want to learn more about Nitrox and why you should be using it. Check out Nitrox.com