text: In 1993, the Sub-Aqua Association was the first UK recreational diving training agency to acknowledge and endorse the Nitrox training their members had undertaken with one of the tech agencies. The SAA's first recreational Nitrox qualification was issued in April 1993. The SAA's first Nitrox instructor was Vic Bonfante and he was certified in September 1993.
  Meanwhile, diving stores were finding a purely economic reason to offer nitrox: not only was an entire new course and certification needed to use it, but instead of cheap or free tank fills with compressed air, dive shops found they could charge premium amounts of money for custom-gas blending of nitrox to their ordinary, moderately experienced divers. With the new dive computers which could be programmed to allow for the longer bottom-times and shorter residual nitrogen times that nitrox gave, the incentive for the sport diver to use the gas increased.
  In 1993, Skin Diver magazine, the leading recreational diving publication at the time, published a three-part series arguing that nitrox was unsafe for sport divers. DiveRite manufactured the first nitrox-compatible dive computer, called the Bridge, the aquaCorps TEK93 conference was held in San Francisco, and a practicable oil limit of 0.1 mg/m3 for oxygen compatible air was set. The Canadian armed forces issued EAD tables with an upper PO2 of 1.5 ATA.