First time getting narced...Yipes!

[wedivebc]

Also, there are some arguments about oxygen's narcosis inducing potential because it is not an inert gas.

BINGO!
That is why it is so hard to make a conclusive argument either way.
I am not sure what theory DIR-Atlanta is talking about since Meyer-Overton deals with inert gas narcosis so it's a pretty big leap to say just because oxygen is more soluble in lipids it has higher narcotic potential. The experts in the field can't agree on how much effect a metabolized gas has on narcosis I am curious, what theory do you base this statement on?

In theory, Oxygen should be twice narcotic as Nitrogen,

 

[The Chairman]

Read what ANDI sent me... it's hard to say whether these experiences are narcosis or the beginnings of OxTox. Surely, you don't think that there is NO toxicity until you start convulsing, right? No one would deny that oxygen can wreak havoc with your nervous system at elevated pressures. However, we just don't know if there is any effect BEFORE we reach the "trigger" point. To suggest that NitrOx will help with narcosis without any empirical evidence is to give divers a placebo where they need a solution. The only VERIFIED solution to narcosis at depth is the introduction of helium into our breathing gas. Saying anything different only muddies the waters for divers seeking to find a solution to deal with their own narcosis.

Here is the REAL problem. We will call this the "threading shrimp fallacy". If you practice ANYTHING, you will probably get better at it. The fact that shrimp seem easier to thread today than yesterday is hardly relevant, when the simple act of repeating this task will by itself make it easier.

Narcosis is a sneaky bastard. There is little to no indication of impairment UNTIL you have to think outside of the box you are in. In fact, the narcosis will usually provide some level of euphoria which in turn masks your ability to critically determine how impaired you are. The ONLY way to measure your impairment, is really to measure your depth. Yes, you may feel the darkness descending on you one day while another day seems just fine at the same depth. It is my opinion that these are merely feelings. Your real impairment has little to do with how you feel but how able you are to react under increasing stress.

In the end, this may be an area where we have to agree to disagree. I see absolutely no benefit in denying my propensity to be narced at any given depth. I see absolutely no reason to trust in the benefit of NitrOx when there are no verified results. Murphy is a mean SOB and I will not put myself in a position where I think that he has less of a chance to rise up and smack me down hard.

 

[Marvel]

If this was your 23rd dive, it was the 23rd time you've been narced. We are all narced on every dive. As we get deeper, the narcosis gets worse. We are not always aware of symptoms, but we are always narced. Making every dive with that concept firmly in mind will make every dive safer.

Bravo!

Walter, that's so true.

I'm a pretty bright person; in fact, I'm kind of known for it. And I'm just plain stupid underwater. It amazes me how long it has taken me to learn to do certain tasks and think through certain problems. I am absolutely convinced that the effect on my thinking is noticeable at 30 feet, and certainly deeper.

Ah... nice to know I am not alone in noticing NN at shallower depths. Like you, mine is of the dark variety the vast majority of the time. I control it by focusing on breathing, my buddy (ies), &, of course, constant checking of my computer & gauges. I've also found that the quality of my buddy is critically important to me. If I am with someone who I feel is a conscientious, safe diver I am more comfortable. If I am with someone who I feel is oblivious to anything but their own diving pleasure, it exacerbates the paranoia. That factor has been resolved by being a lot more selective in choosing my dive buddies.

 

[wedivebc]

Read what ANDI sent me... it's hard to say whether these experiences are narcosis or the beginnings of OxTox. Surely, you don't think that there is NO toxicity until you start convulsing, right? No one would deny that oxygen can wreak havoc with your nervous system at elevated pressures.

The problem is your lumping the mechanism that causes narcosis with that of CNS toxicity. I am not a Dr but I am pretty sure they are 2 seperate entities even though the symtoms overlap which is what ANDI is stating. It is not that the phsiology is connected only that symptoms of one can mimic symptoms of the other and CNS symptoms should always be treated with the greatest level of concern
I am agreeing with WRT not using nitrox as a reliable way to reduce narcosis I just am debating whether one should take such a firm position on O2 narcosis since the true experts are less certain of the effects that we as layman seem to be.

 

[The Chairman]

The problem is your lumping the mechanism that causes narcosis with that of CNS toxicity.

No, that is not what I am doing here. The only obvious commonality is pressure, and that's all I have really alluded to. The issue I have, is that we are treating toxicity as "all or nothing" and I am not sure that this is the best way to approach it. Perhaps, we have been assigning some of the symptoms of toxicity to being narced or the other way around without realizing it.

What I am certain of is that to assign a diminished narcosis as a possible benefit of NitrOx is not a wise decision. It gives a false impression of increased safety at depth to many who would cling to this as tightly as some used to cling to the need for horizontal off gassing. This is a WAG as a opposed to a SWAG: A lot of wild ass guessing and no science to attach it to.

 

[Rick Inman]

Ah... nice to know I am not alone in noticing NN at shallower depths.

Like, ah.. on the surface??

 

[Marvel]

Like, ah.. on the surface??

It's too COLD right now for us wimps, Rick! Come back for ITK & we'll dive... BTW, why didn't you see my light get dropped?

 

[nereas]

I don't buy it. I know my observations. I do agree that the rest of the reasons are the more important reasons for using nitrox. Reduced (not eliminated) narcosis is just a side benefit.

There is no reduced narcosis with nitrox compared with air. You need to get over that false notion. Like Pete said, you are inviting disaster if you do not.

And your inaccurate comments to the contrary are making your postings a liability to other less experienced users.

Hopefully several of the fine contributors here have helped you to see why. One such person has quoted NOAA. And I have given you scientific data quoted in technical diving manuals regarding lipid solubility experiments.

When an ostrich sticks its head in the sand, it does not change reality, it only affects its own perception of reality. If a nearyby lion is hungry, the lion will still get an easy meal. That is reality.

 

[perdidochas]

Read what ANDI sent me... it's hard to say whether these experiences are narcosis or the beginnings of OxTox. Surely, you don't think that there is NO toxicity until you start convulsing, right? No one would deny that oxygen can wreak havoc with your nervous system at elevated pressures. However, we just don't know if there is any effect BEFORE we reach the "trigger" point. To suggest that NitrOx will help with narcosis without any empirical evidence is to give divers a placebo where they need a solution. The only VERIFIED solution to narcosis at depth is the introduction of helium into our breathing gas. Saying anything different only muddies the waters for divers seeking to find a solution to deal with their own narcosis.

Here is the REAL problem. We will call this the "threading shrimp fallacy". If you practice ANYTHING, you will probably get better at it. The fact that shrimp seem easier to thread today than yesterday is hardly relevant, when the simple act of repeating this task will by itself make it easier.

Prior to fishing for them at depth, we had done quite a bit in shallower water.

Narcosis is a sneaky bastard. There is little to no indication of impairment UNTIL you have to think outside of the box you are in. In fact, the narcosis will usually provide some level of euphoria which in turn masks your ability to critically determine how impaired you are. The ONLY way to measure your impairment, is really to measure your depth. Yes, you may feel the darkness descending on you one day while another day seems just fine at the same depth. It is my opinion that these are merely feelings. Your real impairment has little to do with how you feel but how able you are to react under increasing stress.

Probably. Actually, the main thing I learned from this incident is that I was more effected by narcosis than I thought at 100'. If anything, it has made me a more cautious diver at depth.

In the end, this may be an area where we have to agree to disagree. I see absolutely no benefit in denying my propensity to be narced at any given depth. I see absolutely no reason to trust in the benefit of NitrOx when there are no verified results. Murphy is a mean SOB and I will not put myself in a position where I think that he has less of a chance to rise up and smack me down hard.

When did I say I trusted nitrox for this purpose? I do trust it for allowing longer bottom times, but not for narcosis.

 

[perdidochas]

There is no reduced narcosis with nitrox compared with air. You need to get over that false notion. Like Pete said, you are inviting disaster if you do not.

ANDI seems to disagree. Anecdotally, I noticed it. I don't see how it's a dangerous thing to believe. It doesn't change my behavior. I'm not going to try things at 100' on nitrox that I wouldn't do on air (except for bottom time).