How narked are you ?

Hi guys & gals
Last week I met some of my diving mates down our local pub for a few beers and our mandatory curry during the evening we started to talk about deep air diving and 2 of my mates said they never feel narked when diving to 50m on air. So I offered to have a dive on saturday to prove them wrong my arguement was any body going 30m or deeper will get some sort of on set of narcosis. On saturday morning I had the car packed and was on road for 6am as I had a good 2hrs 30min drive to get to the quarry once there I went through the dive plan with them what was desending down the 50m shot line to a max of 30m then swim off the line to the wall for a wall dive max time down was 15min so we only would have a 3 min saftey stop. They were not allowed any deeper than 30m for the hole dive and I would signal to them to note there air plus there buddies air on a slate approx half way through the dive on the dive I would be trying to make them go deeper than 30m. So off we went we got down to 6m and done a bubble check then went down to 30m at 30m we left the shot and started our dive half way through the dive I gave them the signal to log there air plus there patners then turned the dive around to go back to the shot half way back I pointed and started to descend both of them followed me down to 38m before one of them remebered the dive plan and signaled to go up it was that easy to break our dive plan and get them deeper. Back at the surface after we had done our saftey stop we looked at the slates one of my mates had recorded hes air but not hes buddies the other had recorded both but both had followed me deeper than the dive plan the other thing that they did not do was ask the other what air they had left but both were looking at there gauges most of the dive. Both of them agree now even though they did not feel narked there was a degree of narcocis.

If you really want to feel the effects of narcosis go for a joy ride in a chamber. I get hit pretty hard by it and have felt it as shallow as about 25-27 metres but in the chamber i started to feel the effects at 2 metres. Yep 2. I think the environment has a lot to do with its onset as well. Cold dark water seems to bring it on quicker than warm clear water. On a 2 week trip to the Solomon Islands we were doing 60-70 metre air dives everyday and i felt less and less every dive. We did a 40 metre dive late in the trip that felt like it was 10 metres. My head felt real clear with no real effect.

Matt

Hi zero
yes. I make you right about pot dives we done one down 50m I found that I had to equalise a lot more compared to doing a proper dive. With the 60-70m air dives only ever been to 62.5m on air water temp was 6oc and to be honest cant really remember to much about the deep part of the dive. As my tech instuctor told me on my trimix course its easy to dive deep on air or trimix till something goes wrong and if sh*t did hit the fan on a deep dive (60-70m) would rather be on trimix as i would have a clearer head for sorting the problem out.
regards
nick

They are a riot. Everyone goes in quiet and nervous until the pressure goes on a little bit and at about 5 metres the attendant asks if everyones ok and then people talk like chipmunks and no one can stop from there down and back up till they go onto the oxygen bibs. Then its time to sit back relax and think about all the stupid and embarassing things you have just said and done. Me included.

Matt

Oh mate LOL you have hit the nail on the head there. With regards to the embarassing things said and done thats sounds like the morning after the pub thing on a saturday night out.

I've been down to 165 on air as the diluent and I should have felt a tad narked but I didn' t notice anything different, but it would have been fun to do some cognitive skills at that depth to really see.

Interesting thread, me and my dive buddies have been discussing this alot lately. Everyone gets narc'd, but what they "perceive" is so subjective. I think it was DCEIM did studies with divers on deep air for a week, doing the same profile and tasks repetitively. At the end of the week all the divers reported being much more adapted to the narcosis and able to cope and handle the tasks much better. But turns out the data showed they were still making the exact same mistakes they were making on day one . . .
A group from our club headed out last x-mas eve to dive in a lake that has a gentle slope down to 500+ feet (what's that? 150+ meters?). Most stayed in the 10 to 20 meter range, but two "instructors" led a basic diver on a bounce dive to 150' (45m). One instructor wore double 80cu ft. tanks, the others wore single 100 cu ft. tanks, one of these had a 30 cu ft. "pony bottle", the other a 19 cu ft. "pony bottle". All diving air. The basic diver claimed afterwards he felt no narcosis at all, but when asked about the dive all he could remember was that his buddy's light looked "so beautiful down there. I couldn't stop staring at it". The instructor in the doubles, all though admiting he felt terribly narc'd, reported seeing the basic diver laying on the bottom mindlessly drawing circles in the sand with his finger. The other instructor disappeared when the max depth was reached, and nobody even thought to wonder where he was until they surfaced! Water temp was about 37F/3C. viz about 30'/10m at depth. If just one thing had gone wrong down there, such as a freeflowing reg, it's doubtful all would have returned to the surface alive.

I agree that narcosis is definitely influenced by environment. The warmer or even clearer dives that I have done have felt like I was in two feet of water when I was at 60, etc. Quarries tend to feel deeper than they are. I never had many signs of narcosis, but my dive buddy did once. We were doing a dive to 92 feet in a quarry in PA. We were doing an activity sort of like the one you described, only ours was long division. I gave him a problem, and he had no clue where to begin even. Then he didn't really know which way was up. Kind of scared me.

By far the worst one is asking people to write their phone numbers down. Never seem to get the right numbers:mad: :D :D :eek:

Matt

last week I did a dive to 127 fsw as part of my AOW course. at depth, I had to put together a puzzle and write my name on a slate. The puzzle was several pieces of pvc pipe of various lengths with elbows and connectors to form an odd shape. I messed with it on the surface before the dive so I had an idea of how it went together and which pieces I should start with. Also, I wrote my name on the top of the slate before the dive and wrote it again at 127 fsw. The water temp was 82F and viz was around 70 feet.
I did not feel any narcosis but was aware that it is insidious in that you can be narc'd and not know it. I had no trouble putting the puzzle together and wrote my name identically to how I had wrote it on the surface. Just the same, I dont think I shall be returning to such depths unless I have a very good reason.

It's been said that every 33' is equivalent to downing a shot of hard liquor. Are you just really used to downing hard liquor? Kidding! :) Everybody's reaction to narcosis is different, but it does happen to everyone. You are smart to only go to those depths when you have a good reason, instead of just so you can say you did it.
Training could be a valid reason. Which agency were you taking your Advanced cert with?

Well, I just stay drunk all the time. That was the narcosis wont bother me @ 200' on air ;)

Quote:

---

Originally Posted by seasnake

It's been said that every 33' is equivalent to downing a shot of hard liquor. Are you just really used to downing hard liquor?

---

Would that be Martinis Law?

Matt

Quote:

---

Originally Posted by seasnake

Training could be a valid reason. Which agency were you taking your Advanced cert with?

---

...NAUI...

I routinely do dives on air to 180-200 ft (my absolute basement). Of course I experience narcosis. My method of evaluating the severity of it is whether I can (1) locate subjects to film at depth, (2) frame them properly and hold the camera on them and (3) follow them as they move.

Some believe that frequent divers like myself (over 300 dives last year) acclimate to nitrogen to some degree and do not suffer extremes of narcosis. I sense that may be the case. I know I am narced as I've tested my ability to perform tasks at the surface and at 100 ft, and the effect is noticeable but not debilitating in any significant way. If I feel something isn't right at depth, I immediately ascend until things clear up.

I do not advocate such diving to anyone else. I only do it to film subjects at these depths for a video on "Deep Ecology."