planning a deco dive

[espenskogen]

No technical diver that I know uses nitrogen to control the effects of O2 exposure. The way we do that is by limiting O2 exposure. Do you teach technical diving?

No I don't teach tech diving, and of course we don't use nitrogen to control the effects of O2. But if you read the full sentence, I said that if you were to go to 70 meters on normoxic trimix (Which is not recommended), you were more likely to tox than 70 meters on air (Which is still not recommended).
The right way of doing it however would be to do 70 meters on an hypoxic mix.

The discussion here though is a 60 meter dive, which is within the exposure limits.

 

[Scuba_Steve]

Interestingly enough, it is often the instructors and instructor trainers (as in the article about the TDI lot) who are the worst offenders when it comes to diving way outside the limit of their training. Whilst they should know better, I guess it's easy to get carried away.

Which is why one shouldn't be training under such idiots in the first place. If they're that careless, and yes I agree I have seen some that are, then they're the last people that should be influencing new students.

I know several Padi instructors who have done 120 meters on air. Is it stupid? Yes. Would I recommend that anybody go that far beyond their training? Absolutely not. Can it be done? Yes, just about.

Well, I too have read about your recent Instructor status, and like the gents above am left scratching my head as to you comments on this thread. Don't get me wrong, I too have seen and actually have had padi instructors ask me to take them "deep diving". They're just clued to the reality of the whole thing, and I wonder how they can really think I would do such a thing. It's bread in the whole mainstream rec diving mindset unfortunately.

LOL, actually, this whole thread reminds me of seeing how far I could stick a baseball bat up my arse, I mean, I could do it, but I don't really see the point in it.

Pardon the visual.

 

[espenskogen]

You are wrong on so many levels and I have had friends who thought the way you do. Of those friend many now think differently and at least 7 of them are DEAD from the exact same mindset you display.

Honestly, if I had been your course director and you had displayed these attitudes you would not be an Instructor.

Please take some time to really learn about this stuff.

Best,

Chris

ps- reintroducing nitrogen(narcosis) deep (really deep like below 400fsw when using helium based mixes) has proven to reduce HPNS, NOT O2 tox. That may be one small area where you are confused among others.

Sorry to hear about your friends, but I don't think you quite get what I'm saying though. Read my other reply and let me know.

Yes, I am aware of the benefits of nitrogen in reducing HPNS - That's why we use trimix rather than heliox, combined with slowed down decent rates between 120 and 180 meters. But no, that's not the confusion, although it's ability to reduce HPNS is very similar to its ability to delay the onset of O2 tox. However, this is neither here nor there, as the dive we were discussing is within the exposure limits.

 

[andydiver06]

Fantastic point of view Espen and other senior members. I have observed that lot of people in this forum starts questioning your capability (mostly senior members) instead of giving proper advice. This is a forum where we are supposed to gain knowledge and get out doubts clear. Hope we are in a democratic forum where people have their choice. If somebody spear fishes or dives deep that his choice. People can only advice them the pro and cons instead of starting to hit them with their training records.

 

[espenskogen]

Well, I too have read about your recent Instructor status, and like the gents above am left scratching my head as to you comments on this thread. Don't get me wrong, I too have seen and actually have had padi instructors ask me to take them "deep diving". They're just clued to the reality of the whole thing, and I wonder how they can really think I would do such a thing. It's bread in the whole mainstream rec diving mindset unfortunately.

I'm not endorsing it - Just discussing it. Not sure how my recent instructor status changes anything? I did the IDC ages ago, and didn't actually learn much new about diving physiology or physics there. (Was too cold to do the IE straight off the back of the IDC).
The dive we're discussing here is well into the technical arena, and as such, I'm just discussing it as an average tech diver.

LOL, actually, this whole thread reminds me of seeing how far I could stick a baseball bat up my arse, I mean, I could do it, but I don't really see the point in it.

Pardon the visual.

It does a bit, and my argument here, is that if you were intent on doing it, and I was a physician who knew a bit about how to minimize the injuries following your baseball bat stunt, then I'd feel compelled to give you some guidance as to the proper training for such stunt.. But then I guess your name is not David Blaine, and I'm not a physician - And with a bit of luck, not even young Blaine will think up quite such unsavory stunt

 

[ScubaSixString]

Did any of you read his reasons for wanting to do this?
"I want to see what happens". Why would anyone advocating this type of dive given this reasoning? I may be off base here, but "I want to see what happens" sounds like a good way to get himself in trouble.

 

[espenskogen]

Did any of you read his reasons for wanting to do this?
"I want to see what happens". Why would anyone advocating this type of dive given this reasoning? I may be off base here, but "I want to see what happens" sounds like a good way to get himself in trouble.

Yes, I guess in that sense I agree, it might not be the best reason to do it. A lot of divers do deep dives simply to experience narcosis. But as I suggested, by building up your experience by doing gradually deeper dives, you're going to experience enough narcosis to last you a life time - And it gives you the chance to stop once you've reached the limit of your comfort zone.
Some places though, there are lots of deep wrecks.. Now that's a reason to go deep..

 

[Scuba_Steve]

It does a bit, and my argument here, is that if you were intent on doing it, and I was a physician who knew a bit about how to minimize the injuries following your baseball bat stunt, then I'd feel compelled to give you some guidance as to the proper training for such stunt..

You mean there's actual training for the baseball bat stunt???

Probably endorsed by the deep air pushers I would suspect.

Look, I'm not going to bag on you. You seem like a really nice guy and your heart is in the right place (trying to help), but what you purpose by even stating that it is do-able (read: bat-stunt) is NOT what we should be stressing here, which is why you see Chris and Mike getting in your face on that.

It just pushes the entire wrong aspect, and is a means to nothing. It's stupid and rarely have I seen a real compelling reason put for to do so in this day and age. and "Just to see" isn't one of them.

As Chris said, there's just so much wrong with this, it gets rather annoying, and so you get the responses you do.

Regards

 

[ScubaSixString]

Yes, I guess in that sense I agree, it might not be the best reason to do it. A lot of divers do deep dives simply to experience narcosis. But as I suggested, by building up your experience by doing gradually deeper dives, you're going to experience enough narcosis to last you a life time - And it gives you the chance to stop once you've reached the limit of your comfort zone.
Some places though, there are lots of deep wrecks.. Now that's a reason to go deep..

I'll admit, i'm no deep or deco diver (yet). I've been in places i shouldn't have. But this fellow's post appears to make it abundantly clear he is not deco trained, nor deep air trained, nor ready for this type of thing. He reasoning for wanting to do this type of dive calls his judgement and maturity into question. Again, i may be off base, and i apologize if thats the case. I haven't run the numbers, but apparently 60m is within meters of a PPO of 1.6. And, although its highly diver specific and apparently higher PPOs can be "worked up" to, 1.6 is the reccommended limit for the RESTING part of a dive, not the working part.

Again, reccomendations are a dime a dozen, but with something that can kill you as quickly as a CNS hit, i'd encourage folks to be conservative.

Not to bust your chops too heavily here, but I want to go dive 2000ft back into a cave system, because it sounds cool. Any advice?

See my point? This guy may well do this anyway, as is his choice, and should be his choice, but, to some people, having a person say do this...this...and this and it should be doable is 1>what they want to hear and 2> liscense to kill themselves.

In my humble opinion

 

[espenskogen]

I'll admit, i'm no deep or deco diver (yet). I've been in places i shouldn't have. But this fellow's post appears to make it abundantly clear he is not deco trained, nor deep air trained, nor ready for this type of thing. He reasoning for wanting to do this type of dive calls his judgement and maturity into question. Again, i may be off base, and i apologize if thats the case. I haven't run the numbers, but apparently 60m is within meters of a PPO of 1.6. And, although its highly diver specific and apparently higher PPOs can be "worked up" to, 1.6 is the reccommended limit for the RESTING part of a dive, not the working part.

Again, reccomendations are a dime a dozen, but with something that can kill you as quickly as a CNS hit, i'd encourage folks to be conservative.

Not to bust your chops too heavily here, but I want to go dive 2000ft back into a cave system, because it sounds cool. Any advice?

See my point? This guy may well do this anyway, as is his choice, and should be his choice, but, to some people, having a person say do this...this...and this and it should be doable is 1>what they want to hear and 2> liscense to kill themselves.

In my humble opinion

Fair point, I guess I didn't want to say 'yes it can be done, but YOU can not do it, because I don't think you're skilled enough', and besides I've spent a lot of time discussing/doing this kind of dives (safely) so I suppose I might have gotten a bit too enthusiastic about the whole thing...

So for the record then - And this one is for you Chris, Mike and Steve - In the case of this diver we're talking about, then DON'T DO IT.

Certain divers with lots of experience and training can do sixty meters in safety. If you are not one of them, then stick to the limits of your training.

Thank you - Checking out