Editing Nitrox (section)

==History==
In 1874, [[Henry Fleuss]] made what was possibly the first Nitrox dive using a rebreather.<ref name="Lang 2006" />

In 1911, [[Drägerwerk|Draeger]] of Germany tested an injector operated rebreather backpack for a [[standard diving]] suit. This concept was produced and marketed as the DM20 oxygen rebreather system and the DM40 nitrox rebreather system, in which air from one cylinder and oxygen from a second cylinder were mixed during injection through a nozzle which circulated the breathing gas through the scrubber and the rest of the loop. The DM40 was rated for depths up to 40m.<ref name="Draegerwerk 1899" />

[[Christian J. Lambertsen]] proposed calculations for nitrogen addition to prevent oxygen toxicity in divers utilizing nitrogen–oxygen rebreather diving.<ref name=Lambertsen1941 />

In [[World War II]] or soon after, British commando [[frogman|frogmen]] and [[clearance diver]]s started occasionally diving with oxygen rebreathers adapted for semi-closed-circuit nitrox (which they called "mixture") diving by fitting larger cylinders and carefully setting the gas flow rate using a flow meter. These developments were kept secret until independently duplicated by civilians in the 1960s.{{citation needed|date=July 2015}}<!--This is plausible, as it basically (badly) describes a semi-closed constant mass flow rebreather-->

Lambertson published a paper on nitrox in 1947.<ref name="Lang 2006" />

In the 1950s, the [[United States Navy]] (USN) documented enriched oxygen gas procedures for military use of what we today call nitrox, in the US Navy Diving Manual.<ref name=usn />

In 1955, E. Lanphier described the use of nitrogen–oxygen diving mixtures, and the [[equivalent air depth]] method for calculating decompression from air tables.<ref name="Lang 2006" />

In the 1960s, A. Galerne used on-line blending for commercial diving.<ref name="Lang 2006" />

In 1970, [[John Morgan Wells|Morgan Wells]], who was the first director of the [[National Oceanographic and Atmospheric Administration]] (NOAA) Diving Center, began instituting diving procedures for oxygen-enriched air. He introduced the concept of Equivalent Air Depth (EAD). He also developed a process for mixing oxygen and air which he called a continuous blending system.  For many years Wells' invention was the only practical alternative to [[partial pressure]] blending. In 1979 NOAA published Wells' procedures for the scientific use of nitrox in the NOAA Diving Manual.<ref name=noaa/><ref name=dan/>

In 1985 [[Dick Rutkowski]], a former NOAA [[diving safety officer]], formed IAND (International Association of Nitrox Divers) and began teaching nitrox use for recreational diving. This was considered dangerous by some, and met with heavy skepticism by the diving community.<ref name="Lang 2006" />

In 1989, the Harbor Branch Oceanographic institution workshop addressed blending, oxygen limits and decompression issues.<ref name="Lang 2006" />

In 1991, Bove, Bennett and ''Skin Diver'' magazine took a stand against nitrox use for recreational diving. ''Skin Diver'' editor Bill Gleason dubbed nitrox the "Voodoo Gas". The annual DEMA show (held in Houston, Texas that year) banned nitrox training providers from the show.  This caused a backlash, and when DEMA relented, a number of organizations took the opportunity to present nitrox workshops outside the show.<ref name="Lang 2006" />

In 1992, the Scuba Diving Resources Group organised a workshop where some guidelines were established, and some misconceptions addressed.<ref name="Lang 2006" />

In 1992, [[British Sub-Aqua Club|BSAC]] banned its members from using nitrox during BSAC activities.<ref name="BSACOK" /> IAND's name was changed to the International Association of Nitrox and Technical Divers ([[IANTD]]), the T being added when the European Association of Technical Divers (EATD) merged with IAND.{{citation needed|date=July 2015}} In the early 1990s, these agencies were teaching nitrox, but the main scuba agencies were not. Additional new organizations, including the [[American Nitrox Divers International]] (ANDI) – which invented the term "Safe Air" for marketing purposes – and [[Technical Diving International]] (TDI) were begun.{{citation needed|date=July 2015}} [[National Association of Underwater Instructors|NAUI]] became the first existing major recreational diver training agency to sanction nitrox.<ref name=NAUIhx />

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.<ref name="xray-mag.com" />

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.{{citation needed|date=July 2015}} 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,{{citation needed|date=July 2015}} published a three-part series arguing that nitrox was unsafe for sport divers.<ref group=note>A position which it would formally maintain until in 1995 magazine editor Bill Gleason was reported to say that nitrox was "all right".  ''Skin Diver'' would later go into bankruptcy.</ref>{{citation needed|date=July 2015}} [[DiveRite]] manufactured the first nitrox-compatible [[dive computer]], called the Bridge,<ref name="TDI manual" /> the aquaCorps TEK93 conference was held in San Francisco, and a practicable oil limit of 0.1&nbsp;mg/m<sup>3</sup> for oxygen compatible air was set. The Canadian armed forces issued EAD tables with an upper PO<sub>2</sub> of 1.5 ATA.<ref name="Lang 2006" />

In 1994, John Lamb and Vandagraph launched the first oxygen analyzer built specifically for Nitrox and mixed-gas divers, at the Birmingham Dive Show.<ref name="xray-mag.com"/>

In 1994, BSAC reversed its policy on Nitrox and announced BSAC nitrox training to start in 1995.<ref name=BSACOK/>

In 1996, the [[Professional Association of Diving Instructors]] (PADI) announced full educational support for nitrox.<ref name=padi/> While other mainline scuba organizations had announced their support of nitrox earlier,<ref name=BSACOK /> it was PADI's endorsement that established nitrox as a standard recreational diving option.<ref name="adc" /><!--{{Unreliable source?|date=July 2015|reason=American Dive Center has no "reputation for fact-checking and accuracy" as needed for a reliable source; the statement is too strong to be based on the opinion of an unknown website}} Commented out, but left for reference. Lang 2006 comes to a similar conclusion, and has a reputation as an expert in the field--><ref name="Lang 2006" />

In 1997, [[Professional Technical and Recreational Diving|ProTec]] started with Nitrox 1 (recreational) and Nitrox 2 (technical). A German ProTec Nitrox manual (ref to the 6th edition) has been published.<ref name="Hirschmann" />

In 1999, a survey by R.W. Hamilton showed that over hundreds of thousands of nitrox dives, the DCS record is good. Nitrox had become popular with recreational divers, but not used much by commercial divers who tend to use surface supplied breathing apparatus. The OSHA accepted a petition for a variance from the commercial diving regulations for recreational scuba instructors.<ref name="Lang 2006" />

The 2001 edition of the ''NOAA Diving Manual'' included a chapter intended for Nitrox training.<ref name="Lang 2006" />