I definitely notice narcosis in the form of short-term memory loss in 100' dives in Lake George(cold and dark). Warm and clear water, not so much.
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I definitely notice narcosis in the form of short-term memory loss in 100' dives in Lake George(cold and dark). Warm and clear water, not so much.
Narcosis is really unpredictable. As I said earlier in this thread, I dive to about 50m once a week for our "weekly bimble" and 9 times out of 10 I *think* I can function at that depth without too much trouble. I have noticed differences in how fast/slow things seem to unfold as compared to video, but other than that I don't usually feel overly "impaired".
On the 10th time, however, even though I do these deep dives pretty much every week, something else happens. Last Saturday, for example, during our weekly bimble I started feeling noticeably narced at 30m, which is shallow for me to feel narced, and by the time we got to 50m I was feeling seriously bonked. My buddy knew it. We dive an awful lot together and I have what he calls my "whale song" (involuntary vocalizations that I make when I'm feeling at ease). On Saturday, he heard me laughing instead of vocalizing.
Point is, here, that it's hard to say, "I feel narced when XYZ" because if you dive enough to those depths, there's going to be the odd time that it totally deviates from your expectations.
R..
Worse than the Chinese, "we" will modify responses until they fit into what the "holly cows" want to see and hear.
Pathetic and a prime example that "emotionan attachment" causes similair mental response exhibited in divers that panic.
Being PADI I have never thought of using helium. My deep diving to 120+ feet has been very rare, but on those occasions I haven't felt any noticable effects of narcosis (I know we are affected somewhat and do things slower but maybe not notice). Not that it's at all important compared to one's safety, but I imagine helium costs a lot. Never heard of it above 130'.
I'm not clear about what PADI has to do with this. Helium is considered something to be used in technical diving, and PADI teaches it in its technical program.Quote Originally Posted by TMHeimer
Being PADI I have never thought of using helium.
I have done a few dives over the years including deep dives before helium was used and after. I remember the days of having to buy a Hamilton table to test out Helium since the dives were getting complex and narcosis and O2 were definite issues. I remember being a “guinea pig” for Dr. Morgan Wells and creating our own tables since software was not available yet and we were fining what worked and did not work.
Keeping the foregoing background in mind, I became an early believer in helium enriched dives since it worked. Starting in 1994 I began using helium enriched nitrox by topping up deep mixes for shallower diving since I liked the benefits and began using it on dives less than 100’ often and repetitively during the day.
Personally, I quit diving air long ago altogether as it simply does not make sense at any depth. More recently, I have quit diving Nitrox as well unless helium is not available and its less than 100’ (or teaching a class that requires 32%). That’s right, now days I used helium in all my dives (unless not possible and it is shallow) including shallow reef dives. Why? I found the benefits of Helium far outweigh any drawbacks. The benefits include:
·Less CO2 potential buildup and substantially easier work of breathing
·Low/no narcosis
·I feel better during and after dive
·Able to accomplish much more and solve issues fast
·Why would I not want to be as clear headed underwater as I am on the surface?
... Maybe we should use helium for the entire time we are on the surface and below? I mean don't we want to be as clear headed as possible?