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In following recent communications on techdiver I would like to offer a few comments: First on the recent Aquacorps article. In one part of the material Bob Ramio stated he had been given certification as a rebreather instructor by IANTD with out knowledge of rebreathers. IANTD contacted Bob and he acknowledged that he does not have certification as a rebreather instructor by IANTD nor even as a rebreather diver. The error was due to a customer stating to Bob that he had seen some list where Bob was referenced as a rebreather instructor. The customer was wrong as no IANTD material in house or published, list Bob as a rebreather instructor. At this time Bob is not an IANTD rebreather instructor. Bob is a TDI rebreather instructor. Bob Ramio is a close and valued friend of mine and the overall IANTD family. Bob is an active instructor with IANTD and is certified as EANx instructor, Technical EANx instructor, Trimix instructor, Wreck instructor, Cave instructor (#1), EANx instructor trainer, Technical EANx instructor trainer, Wreck instructor trainer and Blending instructor trainer. Bob is an exceptionaly qualified diver and instructor and somone IANTD is quite proud to have as a member. Bob is the primary author of the IANTD facility standards and its QA program. Randy Bohrer is an outstanding member of the IANTD BOA who has contributed a great deal to technical diving safety, education and support materials. Randy is a EANx instructor, Technical EANx instructor, Wreck instructor , Trimix instructor, Technical EANx instructor trainer, he is in process of completing his trimix instructor trainer, and he is a blending instructor trainer. He is also an experienced and competent cave diver although no longer active in this area. Randy was instrumental in the process of developing a method to track CNS toxicity and his work combined with Dr. Bill Hamiltons is the bases that most folks use to bases their calculations on. He has developed soft wear for many dive computers and is quite knowledgeable in all areas of tek diving. As a BOA member it was Randy who first recommended a QA program for IANTD. Some of you have read disagreements on the net between Bob and Randy, please do not let this affect your opnions of their qualifications both are extremely competent and both are dedicated to diver safety. Hopefully they have resolved their differences. Safety and deep air. First folks on the net should define what they are referring to as deep. It appears that dives to 150 to 200 feet or being compared to dives below 300 feet and that is like comparing a 30 foot snorkel dive to a 130 foot scuba dive. It is not the same animal. As IANTD keeps getting referenced on oxygen limits and deep air limits etc. Let me define these for everyone. Deep air is a course to 130 feet which draws on the technology of technical diving and introduces it to the recreational deep diver. Ythis course employs stress management exercises, it uses either dual outlet valves on single tanks or a pony bottle of at least one third the primary gas supply. It also has the divers using lift bags and reels. It is an intense course. Advanced EANx is a course that evolved from a demand by divers whpo sought more knowledge of EANx use and limited Deco but who did not wisk to bvecome ull fledged tekies. This course expands EANx knowledge, combines accident management, teaches the use of EAN 21 through 40 for bottom mix and up to EAN 50 for safety or real stops. This course also required the use of both a dual outlet valve on the tank and a pony/stage tank. NOTE!! ALL IANTD COURSES MAY BE ENTERED BY EITHER PROGRESSING THROUGH COURSES ARE BY ENTRY THROUGH EQUIVALENT PRACTICAL EXPERIENCE. The po 2 MOD (maximum operational depth) in recreational diving is 1.6 ATA. The working POD (planned operational depth limit) in our text is reflected as 1.4 ATA. Reference page 50 of the Enriched Air Nitrox Student Manual and Workbook. Other recreational programs by IANTD include open water, advanced open water, (these programs are more skill and theory orientated than most other open water training programs), dive master, intro rebreather, rebreather, overhead environment, intro to cave, gas blender, and speciality diver. In technical diving programs which IANTD defines as: All dives requiring a deco stop, all dives deeper than 130 feet and all penetrations into an overhead environment beyond surface light are technical dives. Advanced Deep Air is a training program to a depth of 160 feet. This course is intense in skills developed through the process of accident analysis and combined with a risk benefit projection by the student. It is heaqvy in stress management skills that duplicate knowm situtations that have led to accidents. The theory is that by training divers to react and control these events in simulated siturtation that the diver will be more capable to managing the same situtation in a real life predictment. It is also invloved with detailed dive planning, deco theory, and gas management. Like ALL IANTD courses it requires a minimum specified amount of bottom time and dives. It is time in water that makes quality divers and thus the emphasis on bottom time. Technical EANx is the next program. This course allows dives to depths as great as 170 feet. In this course dives are trained to do exact oxygen toxicity tracking using the IANTD CNS% method. This is quite close to the curve devloped by Hamilton and Bohrer for dive computer use. It has become an established method throughout the industry. This program starts with a 1 100% per minute at a po2 of 1.82 ata- then evolves to 10% per minute at 1.7ata. on down to 2.22 % per minute at 1.6 ATA and from that point continues the curve estabished from NOAA limits just as the Bohrer and Hamilton oli limits. The IANTD curve has been transformed into a linear function to add more conservatism so when the upper limits of the oli is compared to the IANTD CNS% the IANTD values are more conservative for additional safety on training dives. This course adds more stress management and equipment drills along with other skills. It is intense. Both the Technical EANx and advanced deep air program are considered as the foundation for tech diving and are a prerequisite for trimix training. MOD in this program is 1.5 ata POD is 1.4 ata. Reference the IANTD advanced deep air student workbook and the IANTD technical EANx student workbook. Example of MOD-POD A cave dive is planned to 270 feet as the POD this dive would require a mix to not exceed a po 2 of 1.4 ATA. or 15.2% oxygen. The MOD is based on the what if case of a diver having to descend to the floor of the cave to retreive a fallen stage bottle or some other reason. Lets assume the cave floor is at 310 feet. The MOD on a low exertion dive will be 1.5 ata po2 thus the mix would be 14.4 % oxygen. On this dive then the operational po2 would actually be 1.32 ATA due to the requirement to stay within the MOD based on the depth of the cave floor. Technical Deep Air represents the maximum depth IANTD believes to be a reasonable training or dive depth on air. In fact as reflected by the low number of cerified technical deep air divers we are rather effective in pursuading divers to evolve to trimix prior to technical deep air. On the other habd many come into a program with the intention of technical deep air certification but due to the education presented opt to change over to mix. We do offer the program and feel it is a safe one to train divers on.. When we estabalished the 190 foot depth it was based on practical experience and reviewuing accidents plus following the already estabished air deep limits of AAUS, CMAS, NOAA and others. We also feel this program closely follows the material published by Miles and Mc Kay in 1961. This material defined that among experienced deep divers a narcosis risk zone is entered at 180 feet and a danger zone begins at 240 feet. The accidents to experienced deep air divers tend to verify this work. I have survived more than 2500 dives deeper than 200 on air , several hundred below 300 and a all time deep dive of 400 feet . Several of my friends were not as fortunate. All but one of these who died, did so below 240 feet most in the 300 foot range. The one who died more shallow was Randy Hilton who at the time was actually working under my supervision as a saturation support diver on the NOAA sponsored FLARE project. On his day off he and Dr. Dick Williams one of our hyperbaric physicians and a highly experienced cave diver who had added line in Eagles nest with me, Frank Martz, Jim Lockwood and Ike Ikehara did the dive at the nest where Randy died. On the dive Dick was to tie off the o2 while Randy ran the line to 200 feet which is where the permanent line to the upstream tunnel begin in those days. Approximately three minutes into the dive upon having tied off the o2 tanks Dick descended to 190 feet where he found Randy dead. ( sorry Richard Pyle the information you reported from earlier about this accident was inaccurate, Randy did die at 190 not 150 feet) This accident report is in mine and NOAA�s possession it is accurate. Divers will do as many of us did and learn by survival, and some do not succeed, if not given the chance to be taught with proper skills, theory and equipment. It would be irresponsible not to offer deep air training as has been proven in the past, afterall that is why we started this program in the first place. This program actually does more to convince divers to continue deep dives on mix more so than to increasae their desire to repeat these depths or go deeper on air. Billy Deans and myself have propossed to decrease the technical deep air diver to 180 feet which will need approval by the BOA, and our international franchises. If approved this would go into effect in our standards for the 1996 1997 year beginning in July of 1996. Trimix I beleive is self explantatory it is the only safe method to do deep water exploration. Trimix should be used on dives that are deeper than 180 feet and definetly those below 200 feet based on o2 risk, narcosis risk and carbon dioxide retention risk. The IANTD trimix course was established in November of 1991 following much debate by the BOD and other IANTD instructors. The authors of this program started out with considerable reserve and have evolved to the point that we instead of looking at trimix as a limted program encourage it for all deep divers. Trimix like deep air does have its own specific risk such as a more intense deco risk, physiological considerations, and equipment dependency needs. Tom Mount, Billy Deans, Sheck Exley and numerous others were instrrumental in the development of this course. Tom Mount received his basis gas training (heliox in 1959-1960) Tom developed a heliox program at the UM RMAS that was responsible for hundreds of safe mixed dives between 1971 and 1976. At that time mix was used for dives deeper than 240 at the UM RSMAS. A deep air program was used that featured air to 240 feet that resulted in thousands of safe accident free dives to 200 feet and hundreds to 240 feet on air. The mix program featured ten scientist and Tom and resulted in several hundred accident free dives. These were all supported by an onsite hyperbaric chamber. Billy Deans and Sheck Exley were the first ot offer widespread training of divers using trimix and heliair. They both developed programs in the late 80's. IOn addition the WKPP at the time under the direction of Bill Gavin and Parker Turner were entering into gas diving using tables by Hamilton just as the Key West Constoretoum tables purchased by Billy Deand then Tom mount, Jim Badden, Wings Stocks and later on Bob Ramio. Currently IANTD has approximately 80 trimix instructors worldwide. Today IANTD has its own soft ware and waterproof tables for diving trimix. In addition to these programs IANTD offers technical training in rebreathers, cave and wreck diving.
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