Nitrox and Its Impact on the Dive Industry
By Tom Mount, CEO IANTD World Headquarters
November 3, 2000

Nitrox was first introduced to the recreational market by Dick Rutkowski in 1985 after he retired from NOAA as the Deputy Diving Director. During his tenure at NOAA, Dick, along with Dr. Morgan Wells, had developed the use of Nitrox diving within NOAA and for scientific diving applications. Upon retirement Dick looked at all the many safety advantages of Nitrox, which had proven to be true for NOAA Divers for 14 years, and he decided to introduce it to recreational divers. He did this by forming IAND (now IANTD) originally under his parent company Hyperbarics International.

Recreational Divers dive the ideal profile to enjoy all the benefits afforded by the use of Nitrox. For a couple of years Dick was the only retail outlet pumping Nitrox. But soon, due to Dick s efforts, more instructors started teaching Nitrox followed by it becoming more available at dive facilities.

Years	Divers	Instructors	Facilities
1990 - 1991	157	147	7
1992 - 1993	4078	802	83
1994 - 1995	11,576	1,783	150
1996 - 1997	19,021	2,315	312
1998 - 1999	19,669	2,178	327
January - October 2000	9,877	915	160
Totals	64,378	8,140	1,039

From the above it is evident how rapidly Nitrox diving is growing. This community enjoys an extremely high safety record. It is also evident that by the growth in the last three years that the use of Nitrox is becoming more popular and will be a major financial impact on the dive industry. These figures are even more impressive when you realize that in the last few years many other agencies have also begun training Nitrox Divers. Thus it will be interesting to see the collective data regarding the number of Nitrox certified Divers between all of the agencies.

Looking at the above figures it is hard to realize that in 1992 we (IANTD) were required to have a sign at our booth at DEMA posting the perceived dangers of diving Nitrox. During that period and up until the mid nineties Nitrox was controversial. Most dive agencies denounced it, Skin diver magazine called it snake oil . It even had the Cayman Islands disclaiming it and declaring they would not treat divers who got hit while using it. DAN by way of its publication Alert Diver, repeatedly presented it as being unsafe for recreational divers and forecast death and destruction through its use.

But from the later part of the mid nineties onward the benefits overcame the doubts. As Dick Rutkowski states "Science overcomes bull shit". Today every major training organization in the world provides Nitrox courses. Skin Diver, and all major diving publication are supportive of Nitrox. The Cayman Islands became one of the first destinations to totally embrace not only Nitrox diving but even rebreathers and trimix diving. DAN also seems to be reevaluating its position on EANx and maybe its editorial policy in Alert Diver in regard to the use of Nitrox.

Today Nitrox is main stream, and a very viable part of the diving industry. Its use has not only made diving safer but it has also stimulated the development of equipment by manufactures dedicated to use with EANx. So it has added safety for divers and it has produced income for manufactures, training agencies, facilities, resorts, and instructors. All in all Nitrox diving has been a win win situation for the dive industry.

In addition to Nitrox IANTD has certified Advanced EANx Divers, Rebreather Divers, Technical Divers, Trimix Divers, Technical Cave Divers, and Technical Wreck Divers in the use of EANx and helium based mixtures. Plus of course OW diver levels not shown below.

Certification Level	Certification Levels
Advanced Nitrox	7,021
Technical	3,059
Normoxic Trimix	267
Trimix	1,938
Rebreathers	1,028
Overhead Environment	786
Introductory Cave	544
Cave	1,258
Wreck	618
Totals	16,519

From those facilities who track gas fills (many do not) and who also did get their reports in to us on the number of Nitrox fills (recreational mixes only) the following data has been compiled by IANTD:

The total documented to date is:

Year	Nitrox Fills
1999 - 2000 Current	800,321
1997 - 1998	404,811
1995 - 1996	125,132
1991 - 1995	71,002
1985 - 1991 Estimate	10,000
Total Documented Recreational Fills	1,411,266

Note this does not include home brew, etc. For instance while making the decision to or not to pump EANx Ginnie Springs did a 3-month survey of the cylinders being filled at their facility. It was discovered that 95% of all doubles that were filled had 400 to 600 psig of oxygen in them. Thus 95% of the fills they were giving to Cave Divers was Nitrox. If this is projected over a year Ginnie Springs was (is) filling several thousand sets of doubles with Nitrox. These numbers are not reflected in any surveys, as they are not official fills. However this practice was, and to some degree still is, still wide spread in much of the world today. So if you add these numbers to the above ones and use a little imagination it is easy to see that many more fills than we have documented have been made. In fact I would estimate that the number of fills actually made by IANTD Facilities alone would double the figures that have been reported to us. But that is speculation even though it is based on acceptable observations.

There is a large population of Technical and Cave Instructors who make in excess of 300 dives a year and all of these dives are on EANx or helium based mixtures. None of these have had DCS even though they are doing up to 4 dives a day or two really long dives with extensive decompression stops a day. For instance, I personally have made 750 dives in the last two years. All of these were on either EANx or Helium based mixtures with a slight majority of these on CCR with depths as great as 420-fsw and dive duration up to 5 hours. These dives have been on deep wrecks, in caves and on deep walls with a very few being shallow reef dives. I have not experienced DCS nor have the dive partners and students I have been diving with at the time.

From the facilities that reported, no incidence of DCS was returned. This does not necessarily mean that there were no hits but rather that the facilities have no reports of hits from their divers. From a training perspective, with the tens of thousands of training dives being made, many with considerable decompression stop times involved we have no incident reports involving DCS.

Today we have many divers who never dive air at any depth and I think this is an expected trend as air is the most unsafe gas one could dive at any depth. Of the divers I do know who have experienced hits in the last few years they were all diving on air.