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Nitrox workshop dings - Divers Alert Network

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Rubicon Foundation Archive (http://rubicon-foundation.org)Hamilton: A Brief History of Oxygen Enriched AirJohnson Space Center in Houston that is fully equipped with enriched air blending and handlingcapability.Additional DevelopmentsAnother problem that could have become troublesome was the matter of OSHA compliance.Technically speaking, an instructor employed to teach diving would fall under the OSHACommercial Diving Standard. However inappropriate this might be, it is federal law. This hasrecently been mitigated by a variance allowing instructors to breathe the enriched air mixturesand still fall under the exemption of recreational diving that is part of the OSHA standard(OSHA, 1999). Without the variance, a chamber would have to be on site whereinstructor-employees are breathing anything but air.The development of technical trimix diving creates an interesting contrast. Extreme rangetechnical diving has drawn much less flak from the recreational industry than enriched air did.Maybe it is perceived that it does not threaten the industry as "nitrox" did. It is just a lot furtherfrom home.This creates a little mixup on what is "technical diving." The definitions above show clearlythat diving with oxygen enriched air is not technical diving. OEA is, however, used in manydeep technical trimix dives as a decom-pres-sion gas, but that is irrelevant to this argument.The development of extended range technical diving has helped generate what I regard as theoxymoron of the day, "Technical nitrox." Bizarre as it may seem, many of the agencies teachthis as a topic. It simply means diving with oxygen enriched air using mixes other than 32% and36% oxygen, and doing dives that involve decom-pres-sion stops. Not a particularly threateningactivity, but one that really has an inappropriate name.ConclusionIn 1995, it became clear that enriched air diving had arrived when PADI took the plunge andbegan teaching it (PADI, 1995). NAUI had been doing it since 1992 with instructors furnishingtheir own teaching materials. In 1997, NAUI made a substantial investment in a new enrichedair manual (Hamilton and Silverstein, 1997). Another organization that had resisted earlier, theBritish Sub-Aqua Club, has come around with its own new set of custom tables, which like thestandard BSAC tables, were prepared with Dr. Tom Hennessy (BSAC, 1995). Skin Diver haseven accepted enriched air, and the <strong>Divers</strong> <strong>Alert</strong> <strong>Network</strong> (DAN) has fully incorporated enrichedair procedures into its records-keeping system.A survey performed for the U.S. Navy in 1999, disclosed hundreds of thousands of opencircuit dives with OEA. In general, except for those done by UNCW, most dives were not welldocumented. Commercial companies do not use OEA much these days. It is still VERYfashionable among recreational divers. The DCS record is actually quite good for OEA dives, as15

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