Home page All gases Synthetic air for diving Home page ... All gases Synthetic air for diving Synthetic air for diving Synthetic air can be used for recreational scuba diving. An appropriate mixture of oxygen and nitrogen for scuba diving 79 % Nitrogen 21 % Oxygen Related gases Oxygen for diving Oxygen can be used for recreational scuba diving. Read more Heliox for Diving Heliox is an appropriate mixture, consisting of helium and oxygen, for saturation diving. Read more Nitrox for diving Nitrox is a widely used mixture for diving up to 164 ft (50m) deep. Read more