deep air

[DCBC]

What got me in here was DCBC's pretty adamant stand that one SHOULD train on deep air before being allowed to do the same dives on mix. Personally, I think that is extremely bad advice. ...But holding the position that all people wanting to do deeper dives should train through impairment to somehow "earn" a clear head just doesn't sit well with me at all.

I don't believe I have said that "all people wanting to do deeper dives should train through impairment to somehow "earn" a clear head." You are mistaken.

What I have said:

1. That the OP's view "about deep air and trimix is an old school one. It was how I was taught."
2. That this "opinion was shared by everyone in the recreational diving community not that long ago, not to mention the military and the commercial diving field. This was to "learn the air envelope before moving on to another gas." There is some wisdom to this."
3. "The philosophy to "learn the air envelope before moving on to another gas" was to encouraged the diver to gain progressive underwater depth experience before moving into deeper water."
4. "Learning to deal with an improper mixture has been valuable (to me) at depth."
5. "It is up to each diver to dive within their own capabilities. It is not however up to anyone to suggest what those capabilities may be with further training and experience."
6. "It's about teaching divers to dive their limitations and how to progressively increase them. I believe this is what continuing education is about."
7. "It is that education and experience that prepares me to deal with underwater "situations" in a more competent manner, than I would have been able to, if I hadn't developed these skill-sets. This doesn't put me in a position to say that because of this I'm better than anyone. It is evidence however that I'm better than what I use to be. For me, that's reason enough."
8. "Dealing with nitrogen narcosis has assisted me in understanding how my body is reacting adversely to other conditions; allowing me to report problems or to hold it together long enough to take action."
9. Anyone who hasn't taken the time to learn really doesn't know what they are talking about, but that doesn't mean they can't have an opinion; it's just an unqualified one. I have heard quite a few of these lately surrounding deep air. If deep air is so unsafe, why are organizations like TDI, IANTD, DSAT, CMAS and others running them? Those who feel these organizations are reckless please stand up and be counted.

It does however bother me when someone jumps to conclusions and mistakenly reports "my position" on an issue.

I'd honestly rather see a relatively inexperienced diver at 150 on mix than me at 150 on air. Yes, mix will "let" a diver get to greater depths with less experience than in the "good old days". Yes, that may sometimes be a bad thing.

I wouldn't encourage either without adequate experience and progressive training.

 

[wedivebc]

I'm going to have to try cold water diving and see the effects of narcosis relative to warm. The cold water divers seem the most adamant about not diving deep air so there must be something to it.........
........
In my experience, only Scubaboard cold water divers have the strong argument against it.
MUst be the cold water.....

I don't think it is the cold at all. A lot of cold water at least around here can be lower visibility for much of the year. Combine that with all thee extra gear such as hoods, drygloves, drysuits, argon bottles etc. and you have a fair bit of task loading.
I personally dive cold 80% of the time and I have quite a high tolerance to narcosis. I don't try to advocate deep(ish) air dives for others any more than I appreciate those who have never or seldom been deep implying I am "barnyard animal stupid". What is stupid trying to change someone's thinking on a subject where both sides of the argument are basing their beliefs on something they have personally experienced.
My personal limit used to be somewhat deeper than 130ft but I have backed off on that. I have been to 200ft on air and for me that was stupid but I will not criticize someone who wishes to do so because it wasn't right for me.
This whole thread is silly because it is a bunch of people arguing about something as subjective as personal limits and experiences.

 

[Thalassamania]

I don't know exactly what the cause is but cold, dark, low vis makes the narc more intense for me and definitely raises the issue dark narc while similar warm, clear dives are much more clearheaded.

 

[DCBC]

I don't ...appreciate those who have never or seldom been deep implying I am "barnyard animal stupid".

That is a little much isn't it?

This whole thread is silly because it is a bunch of people arguing about something as subjective as personal limits and experiences.

Dave, I don't think that this is the case. Deep air training isn't subjective and is not solely based on the experiences of a few divers. Thousands of divers have received recreational, military and commercial training that has been designed to increase a person's safe "air envelope." The success of these types of programs is factual.

Failure to accept this by a few who have no experience with deep air, is what's insane. No one has criticized anyone for choosing not to dive deep air. The only criticism comes from those that don't, to those that do. I believe that this is a more reasonable assessment.

 

[scuba127]

I tend to agree with those that say each individual has to define their own level as to when the switch from air/nitrox to mix needs to be made. I recently did two dives to 130' for 25 minutes bottom time on 28% nitrox. I don't feel like I expirienced any type of serious impairment and I can remember the dives pretty much in detail. These dives were done as part of a deco glass. Based on this expirience and the sum of my expirience doing recreational dives for the past 15 years, I'd have to say at this point that switching to mix at say 100' wouldn't be necessary at least in my case. Right now I feel like this particular agency's cutoff for air/nitrox at 150' is not unreasonable.

 

[firstdive2005]

DCBC-your sentiments in post 181 echo mine. I just crossed over the 5ooth dive. Most of mine have been in warm water. I bag dive on the west coast a bit. My mentors in diving are highly tech. They where very cautious about the rapture diving I wanted to test. My first deep dive at the HMS Sask at Vancouver island was amazing. At the bottom the guys babysat me throughout the dive. What was cool was I performed at test remarkably well. Putting irregular shaped plastic pieces in a circular holder was the task to show narcosis. The two other new divers did not do as well. When I looked into their eyes they looked nervous anyway. When we got to the deck they calmed down and functioned well there. When we where doing buddy drills they where fine but at deeper depths, nada. Here is an observation of mine. I dont drink anymore. I used to drink to oblivion and do functions I shouldnt. Never had a accident but got caught none the less. I choose to stop drinking because I could not control my stupidity when drunk. Now I drank for many years, tolerance plays a part here to the amounts I could drink and function better that others drinking the same quantities. I had quite drinking for 10 years before my first depth at 160fsw. It was with great anticipation that I was about to experience martini diving and not have stinky breath. For some reason when I got to the surface and said, "so what was I supposed to feel" that everyone said, " your where narced dont worry". I didnt want to argue with them, I felt like a deer in the headlights because I didnt understand or realize what they where trying to tell me as to what the condition I was in or feeling at that depth. I was incredibly eager to go again. Again the narc feeling was not as extreme for me as the others. It never has been. (Maybe I'm being stupid again? this is for the benefit of those that think yes). I bounce a lot to 200fsw for certain things I like to see. I remember the dive, I know there must be some impairment as everyone says there must be. I always am calmly cross checking myself on functioning gear and thoughts when deep.
Now I asked this question before on the board and did not receive very many responses. I am wondering if alcoholic abuse and subsequently stopping alcohol intake can alleviate the affects or sense of the affects from being narcd.
I appreciate this thread. I appreciate your candour on your diving skills. My sentiments on creating a good safe diver in me is critical. Not only so I dont get dead, but I want to have fun doing it. O ya I was one of those kids climbing the rockies with only dust and fingers in the 70s and 80s. Never had a lesson. Hit a lot of peaks. I would love to dive with you one day. kev

 

[dumpsterDiver]

I doubt it is a popular opinion, but it has been my experience that individuals that have a long history of recreational drug use or drinking have developed the ability to function in an impaired state without getting overly "distracted" by the impairment itself. I knew a guy who used to "chill out" by smoking a joint and dropping down to 300 on air, solo on a single 80 tank. He was a dive professional and had dove and used drugs for over 40 yrs.

My personal experience is that scuba diving when high on pot is a bad idea, but I dove with someone about a year ago who did a whole joint between each dive.

 

[memorex77]

I'd love to have a print function for the whole thread because it's a really valuable discussion. Hard to read it all on screen.

Just today I've completed upgrading my equipment to bp/w, double-12l, O2 stage and so forth in order to start a deep air course along the CMAS giudelines. The DECO-2000 table that's used in the class goes down to 63m (206') and 13min bottom time. Obviously we're going to take it slow. But it's also clear to me that very reasonable people created this table.

In the deco chamber last week I passed a test at 50m, I was just a bit slower than usual. It is hard to concentrate, but it's not impossible. Let's see what I learn in real life. I'll keep you posted.

 

[DCBC]

Now I asked this question before on the board and did not receive very many responses. I am wondering if alcoholic abuse and subsequently stopping alcohol intake can alleviate the affects or sense of the affects from being narcd.

Thanks Kev. Alcohol and inert gas narcosis are believed to be unrelated. There's something called the Meyer-Overton hypothesis which states that narcosis happens when the gas penetrates the lipids of the brain's nerve cells. Here it apparently interferes with the transmission of signals from one nerve cell to another. There are other theories as well and the exact variables are not known.

That said, narcosis can be a considerable danger to a diver. Training should be undertaken before diving deep and common sense really has to prevail. Narcosis can be reduced in some people by reducing the rate of descent, but this of course adds to bottom-time.

Good luck with your diving and check out the Canadian Divers Social Forum. We have some divers on the west coast.

Wayne

 

[MXGratefulDiver]

I doubt it is a popular opinion, but it has been my experience that individuals that have a long history of recreational drug use or drinking have developed the ability to function in an impaired state without getting overly "distracted" by the impairment itself. I knew a guy who used to "chill out" by smoking a joint and dropping down to 300 on air, solo on a single 80 tank. He was a dive professional and had dove and used drugs for over 40 yrs.

My personal experience is that scuba diving when high on pot is a bad idea, but I dove with someone about a year ago who did a whole joint between each dive.

I smoked an awful lot of pot ... and consumed a lot of other sensory-altering substances ... during the 20+ years of my Deadhead lifestyle. I learned to function well enough in that condition to develop a pretty good career as a technical writer ... as well as doing things like skiing and sailboat racing at a fairly competitive level.

However, it never affected my lack of tolerance for alcohol ... nor do I think it has any impact on my ability to deal with narcosis today (although admittedly I've been straight now for almost 20 years).

Somehow I doubt that an adapted tolerance to one has much of an affect on your tolerance to another ...

... Bob (Grateful Diver)