Should I do Padi Deep before TDI deco & Adv Nitrox

[BarryNL]

You lack the experience to have any right to tell me about when I'm narked and when I'm not.

It's strange - when I drink alcohol I become, as far as I can tell, the most witty and articulate person in the room. Other people may think different but I've been drunk hundreds of times so I know best how it affects me.

Ok, not trying to be sarcastic here but just trying to make the point that unless it's been tested objectively then you really don't know how it affects you. Your personal subjective experience of narcosis is not necessarily realistic.

 

[Thalassamania]

It's strange - when I drink alcohol I become, as far as I can tell, the most witty and articulate person in the room. Other people may think different but I've been drunk hundreds of times so I know best how it affects me.

Ok, not trying to be sarcastic here but just trying to make the point that unless it's been tested objectively then you really don't know how it affects you. Your personal subjective experience of narcosis is not necessarily realistic.

My reactions to narcosis have been tested throughly and objectively, by outside observers. Consider that I've made several hunderd chamber dives over the years (some wet and some dry) and a fair number of those involved human performance studies, not to mention time spent in saturation.

 

[BarryNL]

My reactions to narcosis have been tested throughly and objectively, by outside observers. Consider that I've made several hunderd chamber dives over the years (some wet and some dry) and a fair number of those involved human performance studies, not to mention time spent in saturation.

Fair enough; though of course the advice still stands for everyone else. Unless you're lucky enough to be able to get a properly conducted objective evaluation of your performance under high ppN₂ and ppO₂ you should assume you are narked even if you don't feel it.

 

[Thalassamania]

Fair enough; though of course the advice still stands for everyone else. Unless you're lucky enough to be able to get a properly conducted objective evaluation of your performance under high ppN₂ and ppO₂ you should assume you are narked even if you don't feel it.

I'm not saying that I'm never narced, what I'm saying is that it is a matter of degree. It varies from day to day and with conditions and I've thumbed dives because they just didn't feel right. It's a cost benefit trade off and, at least for me, it sometimes comes down to a economic decision that compares the cost of mix with the cost of scrubbing the dive for another day. At a highly remote site the costs are waaaaaay more than at your LDS, since you'll have to bring pre-mix or everything you need to home-brew, One of the joys of rebreathers is that this issue goes away.

My point is that there are no absolutes. Diving air to 100 feet, or 130 or 150 or even 190 is not automatically the action of a staggering slob out in search of the wah-wahs. Kool aid is every bit as debilitating as diving too deep on air on a bad day.

 

[Steve R]

I'm not saying that I'm never narced, what I'm saying is that it is a matter of degree. It varies from day to day and with conditions and I've thumbed dives because they just didn't feel right. It's a cost benefit trade off and, at least for me, it sometimes comes down to a economic decision that compares the cost of mix with the cost of scrubbing the dive for another day.....

Well, if you put it that way, I can see the reason, if not the unadulterated logic.

This tells me you knowingly go into it not being entirely sure if today will be the day the narc is worse than the last time. An educated best guess based on years of diving, if you will.

When someone can totally defy nitrogen and CO2 induced narcosis all the time, every time and prove it via a published study (not just their word and that of a few other non-descript testers), I will be the first to shake their hand.

Doing it is questionable enough, teaching it to the masses is even worse in this day and age.

Oh, and I'm for letting people do what they want outside of that, just so everyone knows.

Personally I find a zero tolerance, just like not having even a single alcoholic beverage prior to driving is beyond any doubt or logic, THE best single approach in all cases.

Certainly less than best approaches will also work far more often than not, to the point that I still know otherwise intelligent people that think nothing of getting behind the wheel impaired, with their family in tow, because they've done it successfully so many times. So far they have a perfect score, so who's to argue?

regards

 

[Thalassamania]

Well, if you put it that way, I can see the reason, if not the unadulterated logic.

Excellent!

This tells me you knowingly go into it not being entirely sure if today will be the day the narc is worse than the last time. An educated best guess based on years of diving, if you will.

Not entirely sure and more than willing to chicken out is a fair way to describe it.

When someone can totally defy nitrogen and CO2 induced narcosis all the time, every time and prove it via a published study (not just their word and that of a few other non-descript testers), I will be the first to shake their hand.

Me too.

Doing it is questionable enough, teaching it to the masses is even worse in this day and age.

I don’t teach anything to “the masses.”

Personally I find a zero tolerance, just like not having even a single alcoholic beverage prior to driving is beyond any doubt or logic, THE best single approach in all cases.

I don’t drink any alcohol 48 hours before diving, there is not need to drink, it’s just stupid. But there is a need to dive, no dive is safe, but minimizing risk is always a matter of making intelligent choices before the dive and during the dive.

Certainly less than best approaches will also work far more often than not, to the point that I still know otherwise intelligent people that think nothing of getting behind the wheel impaired, with their family in tow, because they've done it successfully so many times. So far they have a perfect score, so who's to argue?

regards

I am lucky, I don’t get narced easily and I don’t particularly care for the feeling comes with any form of inebriation. I’ve been blessed with the opportunity to learn what it feels like, and to fine tune my own judgment about how much I can put up with, under what circumstances. I just get a little hot under the collar when it seems to me that folks who have fewer dives under their belt than I have chamber runs are up on a high horse about something they have no experience with, something that likely their instructors have no experience with. Everyone just spewing the party line with no real understanding of the issues and approaches actually being taken.

 

[CompuDude]

My point is that there are no absolutes. Diving air to 100 feet, or 130 or 150 or even 190 is not automatically the action of a staggering slob out in search of the wah-wahs.

This is my new favorite quote!

(meant in a good way)

 

[Thalassamania]

Hm ... the Nattering Nabobs of Nitrogen?

 

[texdiveguy]

Kool aid is every bit as debilitating as diving too deep on air on a bad day.

'Kool-Aid' I think is more debilitating most days and probably worse!

 

[Ironman]

You are narked at 100ft no matter what you may beleive. Now to what extent varies.

If your point is that a diver may begin to experience SOME degree of nitrogen narcosis as soon as he/she submerges, and the degree of narcosis increases at some variable rate as depth increases, and that narcosis at any depth may be imperceptible and clinically insignificant but is still present, I wouldn't disagree that it is a possibility.

So for the slow, He reduces narcosis. You make smarter and faster decisions when you can think clearly. To think that you are less narked on 32% than air at the same depth is just dumb.

So, you are saying that reducing the nitrogen content of your breathing gas at a particular depth has no effect on the development of narcosis. That the ONLY change that will affect cognitive function at any depth will be breathing helium (presumably heliox?). That it is therefore the presence of helium, not the absence of a particular concentration of nitrogen, that prevents a reduction in cognitive function at depth. Interesting. I wonder if this is the kind of advanced science that can be learned when space aliens abduct someone for their diabolical experiments.

So when you are at 100ft and doing a deco dive He will keep your head clearer then 32% any day.

What objective data can you offer to support this statement?