50-60m recreational depth?

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Doing a chamber ride to 50m doesn't necessarily produce the same narcotic effect as diving to 50m

We were taken down to 180 ft. I was very stoic, I wasn't going to get narced. They told us they were going to give us a few coordination tests. Everyone was very serious in the chamber, we were going to pass those tests.

We were at 180 ft, I felt fine. They had us touch our nose with our left hand, our right hand. This was easy, We were sitting in two rows facing each other and were told there were some more tests. They had someone get down on all fours. Lift your right hand, put it down, lift your right leg, put it down, lift your left paw (paw?), put it down lift your left leg, bark like a dog. I wasn't narced, I heard them say bark like a dog, Then I heard them say, "Hey Bill is Fido peeing on your leg" The tension was broken we started laughing and laughing, pointing at each other, saying it's not that funny, and laughing and laughing some more.

All it took was something to trigger it.
 
It would seem to me that if someone had a catastrophic loss of air at 60 meters, the ability of their buddie's air to get both divers to the surface would be pretty problematic. One can dive that deep. But if something goes wrong, it might be the last dive.
 
It would seem to me that if someone had a catastrophic loss of air at 60 meters, the ability of their buddie's air to get both divers to the surface would be pretty problematic. One can dive that deep. But if something goes wrong, it might be the last dive.

Agreed.
 
The tension was broken we started laughing and laughing, pointing at each other, saying it's not that funny, and laughing and laughing some more.

All it took was something to trigger it.

Somewhere, I have an old video where several of us did a deep dive and my buddy just started giggling uncontrollably. You can hear it in the background over the breathing and he's just chuckling away for no apparent reason.
 
I was doing a 55m air dive once when the silly phrase "Noise pollution - the Silent Killer" popped into my head for no particular reason. I couldn't stop laughing for about 5 minutes :D


The way I see it - the air content/ratios is the same and the pressure is the same so it should produce the same level of narcosis. I don't have much experience with deep diving but I believe that the effects of narcosis vary from dive to dive even under the same conditions - could the effect in the chamber be the same thing?

Bob pretty much covered in his post immediately after yours - yes the dosage (time/pressure) is going to be the same, but you don't have all the other variables (water temp, viz, equipment etc) in a chamber dive. Also, you know you're doing a chamber ride and that there's really no practical chance of you getting killed or injured, so there shouldn't be any stress/worry which narcosis tends to exaggerate... so you tend to get more of the euphoric effect which CD mentioned

To address the second part of your comment, since there are fewer variables, I would assume the symptoms experienced in a chamber to be more consistent from dive to dive, but that's just my guess
 
One can dive that deep. But if something goes wrong, it might be the last dive.

That was the story to which Bob alluded earlier. A bounce dive to 200 feet, but one of the divers got severely narced and was seen sitting on the bottom. His buddy went down and brought him up to where he became responsive again, but in the process, exerted himself until he ran out of gas. There is NO margin for error at those depths, on those small gas supplies.
 
I've felt some narcosis at depths as shallow as 130 feet, but it is unusual that I feel anything until 160 feet. However, one particular dive, I came upon my buddy (we have a very loose buddy team when spearfsihing) and he had shot his spear into a rock. The 5-ft long shaft was some how horribly lodged into the limestone rock, with the flooper tip deployed (open up) after some penetration of the rock.

As I approached I could seem him working feverishly trying to slam the shaft back and forth as violantly as possible. Both he and I knew he would destroy the speartip, but the shaft might be salvagable. I decided to watch for a few moments, since watching people destroy gear and try to remedy mistakes they have made is kinda funny (both above and below the water).

This is extremely strenuous work and he was busting ass and swearing. :rofl3::rofl3:

After a little while, he gave up on the in/out slamming motion and now tried to rotate the shaft , he quickly bent the crap out of the shaft which instantly made the whole effort futile (snce he must have already destroyed the tip and a bent shaft is worth zero).

Instead of abandonment, he continued to furiously slam the shaft back and forth, twist it, bend it. Whatever...I totally lost it, this was perhaps the funniest thing I had ever seen in my life!

I somehow inhaled some water and started a violent and uninterupted coughing attack. Still, I just watched and continued to laugh my ass off with my mask half filled with water. After about a minute, I began to realize that I really was not breathing enough, I was just choking and laughing at his predicament. I had absolutely no concern for my safety at 130 feet; I have done similar dives hundreds of times, so I was not stressed at all at this depth.

Finally, I realized that I was begining to drown, that this was NOT humorous and I had better stop laughing and start to really concentrate on clearing my airway. It was not until that moment that it popped into my head that I must be narced (stoned) and THAT is why this scene was so funny. The idea had never even closed my mind before that narcosis was afecting me.

I concentrated on coughing and breathing and stopped laughing and was fine within 30seconds. Narcosis is like that for experienced divers, if everything is going fine, you may not notice anything.

50 meters is way too deep for an inexpereinced diver and 60 meters is enough to really ring your bell. Some people would become incapacitated at that depth.
 
The world doesn't automatically come to an end at 130ft like alot of people seem to think. Everyone is right - the margin for error at 164ft (or 200+) is very small, but a bounce to 164ft isn't impossible by an means. In the 'bad old days' we used to go to Maracaibo in Cozumel and do la couple of minutes in the deep and then spend 45-50 minutes hanging at increasingly shallow depths. Not my idea of a good dive these days but at the time I thought it was. There are alot of people that have seen way deeper than 164ft on AL80's and not been anywhere near an out of air situation.
 
I've had to make litteraly hundreds of bounces to 190 for very short tasks using a single 80 (and even a steel 72 back in the day). It's no biggie.
 
50 meters is ~164'. Outside the recreational limit of any agency I know of. A bit ill-advised as well.

25 minute total dive time maybe. 25 minute bottom time at depth on an AL80, doubtful.

The instructor may have taken him to that depth, but I wouldn't call it "recreational." Maybe he was doing an advanced class? Deco procedures?

BSAC tables are to 50m (5mins at this depth before you start incurring deco).

Not saying I think it is ok to have 50m as a recreational depth limit (not going to get into that) but just point out that one agency considers it recreational.
 
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