Deep Air

[Gilldiver]

You may not know it, but helium was available (been used since what, the 1930s?), we allready knew how to breathe in , breathe out, and control our depth and time, and who needed Vplanner? We had phones, faxes and Bill Hamilton's numbers.

It was Gentile, Billy Deans, and Joel Silverstine who got the tables out of Bill early on, say 1990-1993.

Until we had the programs and computer for He, we dove 21/25 - 21/35 with 100% O2 at 20 and 10 as air on NAVY tables. As long as you keep the O2 to 21% which keeps the inert % the same as air, bottom times under 30-40 minutes, and the He under 35% it works and any computer program will have you within 2 or 3 minutes run time for either Air + deco gas of choice (100/50/36/32) or say 21/30 and the same deco gas.

 

[Rhone Man]

I am a bit sad that this turned into the stale old "is deep air acceptable?" debate.

When the allied troops occupied Nazi Germany in 1945 they discovered that in concentration camps, German scientists had been experimenting on Jews, seeing how much salt water they could drink before going insane. This presented allied scientists with an ethical delimna. Clearly the treatment of the prisoners was monstrous; never in any normal conditions would such wholly unethical research (and the word "unethical" really isn't sufficient) would have their work published. However, conversely the German scientists had compiled extremely detailed and valuable research on the subject. Ultimately they decided to publish the research papers.

Happily Bret Gilliam and Richard Pyle were not kept in concentration camps, or executed at the end of their "experiments". But we are given a very unique window to consider and discuss a couple of pretty extreme physiological responses, that are never likely to be repeated (or reported if they ever were).

Given that, it was a bit sad that we couldn't formulate a more constructive conversation.

 

[Doc Harry]

I am a bit sad that this turned into the stale old "is deep air acceptable?" debate...
...Given that, it was a bit sad that we couldn't formulate a more constructive conversation.

Uh..... You brought up the topic of deep air diving, an archaic practice without any advantages in this day and age. What other direction did you expect this conversation to go? Did you expect us to argue about the virtues of deep air diving? (There aren't any.)

 

[Kevin Carlisle]

I am a bit sad that this turned into the stale old "is deep air acceptable?" debate.

When the allied troops occupied Nazi Germany in 1945 they discovered that in concentration camps, German scientists had been experimenting on Jews, seeing how much salt water they could drink before going insane. This presented allied scientists with an ethical delimna. Clearly the treatment of the prisoners was monstrous; never in any normal conditions would such wholly unethical research (and the word "unethical" really isn't sufficient) would have their work published. However, conversely the German scientists had compiled extremely detailed and valuable research on the subject. Ultimately they decided to publish the research papers.

Happily Bret Gilliam and Richard Pyle were not kept in concentration camps, or executed at the end of their "experiments". But we are given a very unique window to consider and discuss a couple of pretty extreme physiological responses, that are never likely to be repeated (or reported if they ever were).

Given that, it was a bit sad that we couldn't formulate a more constructive conversation.

I like your questions but there is way too many narrow minded people on here for that type of conversation. They are always right in their own mindsand thats all there is to it.

 

[LiteHedded]

While helium has certainly captured the hearts and minds of most sport divers, there are a lot of places in the world where the availability of helium or the cost of helium is prohibitive. The more remote an area, the less likely that helium is possible to procure and the more likely such an area would hold very interesting unexplored wrecks, caves or other treasures for divers. Since you cannot keep an explorer from exploring, and since true explorers are rarely defined by dogma or popular opinion, deep air diving will still be conducted even if it receives little attention or just pure condemnation from the industry.

Those divers who find it impossible or impractical to take advantage of the plethora of benefits helium offers, can be supported by a long history of the use of air in sport, commercial, science and technical diving operations. Air is no more a "death gas" than what Nitrox or Trimix were branded. Any gas, in the hands of the wrong person, can be fatal. Gases are tools and no tool is always the perfect tool for every job. Sometimes the perfect tool isn't available and improvisation must be done.

For the sport diver, the decision to not dive if such tools are not available is easier than for others such as scientists who are conducting research in remote areas. It is also easier to thumb a dive due to a less desireable gas when one isn't driven to explore or when one hasn't had deep air experience. The Rouse accident demonstrates that divers who had experience with both air and trimix were not so in love with trimix that they were against diving deep air when push came to shove.

While the future of diving is undoubtedly trimix and rebreathers - especially as a way of using trimix to make diving safer in remote areas while using less of a helium supply open circuit would demand, deep air will be a lifelong partner of divers - even if it were only to be used as a "vintage" gas. I once pointed out to a literature professor that future-thinking sci-fi writers rarely remember that people cling heavily to objects of the past.

The diving industry media will begin to move even the weakest recreational divers away from air in magazine articles, and within a short time after proclaiming air as being archaic and dead, they will begin running stories about revisiting deep air diving. Not all of the science and data is back yet regarding the perils and pitfalls of helium diving for the masses. As time moves on, we may find problems with helium diving that we would scoff at today. While I personally love trimix - I've even got 25/25 in my tanks ready to go for some easy 100 foot training dives this weekend down from the 18/45 I was using on the Jodrey before a trip to Bermuda - I'm not going to write air off. Personally, as a PSAI instructor trainer, I would love to convince Gary Taylor that the Narcosis Management program is archaic, but even I'm surprised at the success of the program around the world, and the passion some of the old guys, who have years of experience using both air and trimix, share for deep air diving.

As I do not have their experience, I am not willing to mock them. I remain a skeptic. However, I am also a hypocrit because I would not be afraid to take air to 130 feet since I have had a long history of doing so prior to a time before nitrox and trimix were even mentioned in the sport diving community. "Deep" is purely subjective. However, I do not believe that most divers should be using deep air. I believe gas protocols would make diving safer for those divers who lack experience in deep diving. The success of GUE and UTD demonstrates it is possible to train the most inexperienced divers to do deep dives safely, efficiently and with a great deal of skill and artistry when stringent training and dive protocols are followed.

We would only be arrogant to believe we have diving gases and their consequences, "all figured out".

the rouses. I remember those guys. They did dive air didn't they? what was it that happened to them again? I forget.

 

[fdog]

Uh..... You brought up the topic of deep air diving, an archaic practice without any advantages in this day and age. What other direction did you expect this conversation to go? Did you expect us to argue about the virtues of deep air diving? (There aren't any.)

• It's cheap
• It's available everywhere in the world
• It's well researched
• It's simple to blend
• .....

All the best, James

 

[Rhone Man]

Uh..... You brought up the topic of deep air diving, an archaic practice without any advantages in this day and age. What other direction did you expect this conversation to go? Did you expect us to argue about the virtues of deep air diving? (There aren't any.)

I had hoped we were going to talk about extreme responses to physiological stresses. Where did I expect it go? Well, actually, thinking about it I suppose you are right - it was just too much to ask.

 

[HowardE]

I had hoped we were going to talk about extreme responses to physiological stresses. Where did I expect it go? Well, actually, thinking about it I suppose you are right - it was just too much to ask.

People are too closed minded, and just want to spew anecdotal "experience"

 

[Chatterton]

Prior to 1993 and desktop decompression programs, there was no such thing as a comprehensive set of tables. Each table, including the tables Billy Deans had, were cut for a particular depth, a particular time, and for a particular bottom mix with specific deco gas(es). No one really had a handle on optimal gases, and as we gained experience things changed. It was all very dynamic. More complex were Repet dives, which could be cut for a specific interval, or they could be interpolated to save money.

Bill Hamilton, John Crea, and Randy Bohrer were all capable guys who were available to create tables for sport divers, for a price. The cost was roughly $100 for a specific table. With the high cost, we tried to standardize as much as possible, so we had "Doria Tables", "U-boat Tables", "Choapa Tables", etc for specific depths. If you went over on time, it was best if you had a Back Up Table. If you screwed up your mix, you had to either have another table, or fix the mix. This situation retarded the use of Trimix, by making it expensive and adding risk.

In early 1993, Dan Nafe and another guy came up with the Mig Plan. It was a DOS based deco program. You could run any number of dives, change bottom times, change deco gases, change times, and then print the results. From the comfort of your home, you could actually plan the Trimix dive for optimal gases, and prepare for contingencies. It was true liberation, and all for an investment of $35. It was slow and you had to manually enter a gas for every stop depth, but it worked. Other programs like Chris Parrot's Abyss followed with more features like Windows, and of course at a greater cost.

The desktop program enabled us to compare what worked, to what worked better. When John Yurga and I went to Lusitania in 1994, we were diving a heavier Trimix, but using a 3 gas deco with air, 50%, and O2, to accelerate the deco. The Brits by comparison started out using a minimal amount of He, and then doing their entire deco on 32%. They actually carried two sling bottles of 32%!! Yurga and I were staying on the bottom longer, and getting out of the water faster. After a day or two where Yurga and I proved our approach by not dying, the Brits adopted what we were doing.

The point I am trying to make is that as a community, changing attitudes and acquiring the knowledge to make better decisions relative to gas selection, took a lot of time and experimentation. It took years, and a lot of innovation. The divers who were diving deep air, did so because they had to, or they did not know better. At the same time, they were all incredibly experienced divers, who had slowly had learned the intricacies of narcosis, and decompression over hundreds of deep dives, unlike the vast majority of divers today.

That was then, and this is now. IMHO, it is important to see things for what they are, and use the right tool for the job.


Cheers

JC

 

[Chatterton]

With regards to the Rouses, their Last Dive was made on air but it was 1993 and roughly half the other divers on the boat were diving air as well. Although the use of air undoubtedly contributed to the serious nature of their situation on the bottom, it was not what killed them.

After everything on the bottom had gone bad, they did a free ascent off the wreck, and miraculously located the anchor line at about 100 feet. They had a way back to the boat, they had gas to breath, and with one minor exception their gear was working well. Chrissy's mouthpiece, on their one deco bottle, apparently had a small hole in it and he was getting water with every breath.

With everything that had happened, being entrapped in the wreck, getting lost, having to make the decision for a free ascent, and now having an issue with the regulator, Chrissy had enough and chose sunshine and seagulls, from 100 feet. Chris followed his son.

They had everything they needed to survive with them, except the resolve to stay in the water and complete their decompression, or at least some part of it. For their indiscretions, sadly they had to pay the price.

Resolve and determination, not air.



Regards

JC