I’d like to start using nitrox (EAN) in a scuba tank in which I’ve only been using air. Can I do that?
Yes, if you have the cylinder properly cleaned and tested for oxygen and oxygen-enriched service (i.e., oxygen concentrations above 23.5%). 10. Question: It’s really important that I have enough pure oxygen in my decompression cylinder when I need to use it after a deep dive. Is it okay to put extra oxygen in my cylinder to make sure that I don’t run out? Answer: DOT regulations (see CFR 49) strictly prohibit over-pressurizing a scuba cylinder containing any kind of gas, but it is particularly dangerous to do so with high oxygen concentrations. The reason is: The higher the pressure and the higher the oxygen concentration, the higher the risk of a fire and explosion if a contaminant is present. Luxfer has received numerous and persistent reports that technicians in certain sectors of the recreational diving community routinely over-pressurize scuba cylinders, including cylinders containing high concentrations of oxygen. This is sometimes described as “doing divers a favor,” offering “a
