Rapture of the deep?

[rongoodman]

I've been noticeably impaired at 100' in Lake George, cold and dark, but didn't notice anything at 135' in the Blue Hole, warm and bright.

 

[Kevrumbo]

Yet another thread about our old enemy nitrogen narcosis.

We talk about how to avoid it, detect it and even defeat it. What about enjoying it?

I've come across a few old divers who aren't afraid to admit they simply find it enhances their dive and plan accordingly.

I'm not referring to the thrill seeker, bounce dive, no redundancy, inexperienced, unplanned and largely ignorant divers who end up statistics nor do I support this kind of diving.

However, any of us 'sensible' divers still getting narced on purpose?

If so, what safeguards do you feel you have in place?

Regards,
Cameron

Ps. I hope I don't explode the forum. I'm dangerously near a hot topic on this one.

Ideally Open Circuit double backmount or sidemount cylinders for redundancy with a deco bottle of Oxygen; or at the very least a large single cylinder that will supply enough air to recover from a spiraling Hypercapnic/CO2 episode at depth, as well cover any deco obligations no more than ten minutes maximum. Also utilize a DPV/Scooter to provide mobility & locomotion instead of manually kick finning around -you don't want that pleasant Nitrogen buzz to develop into a cold Dark Narc terror of Hypercapnia because you physically over exerted yourself breathing fast & hard into a vicious CO2 retention cycle. . .

For me in cold SoCal waters averaging 10 deg C at depth, I notice cognitive impairment & degrading situational awareness around 42 meters depth without a scooter and minimal fin kicking (right around that critical air gas density of 6 g/L); if my breathing rate starts increasing and/or have slight symptoms of dyspnea due to increase gas density work-of-breathing, I will abort the dive at that max depth: Stop all physical activity and try to relax & regain a normal breathing pattern again, before starting a controlled nominal ascent to recreational multi-level depths of 21 to 15 m, and stay there for the rest of the dive until final ascent to any remaining mandatory deco stops before surfacing.

From a past Deep Air encounter gone very bad:
. . .I used double AL 11L (AL80's) manifolded cylinders, an AL 11L deco tank of Oxygen, a drysuit for exposure & redundant buoyancy, and a DPV Scooter. Planned dive was a quick powered scooter descent to 90m [on the deep Oil Rig Platform Eureka] for a few minutes, and then multi-level profile up with most of the time spent at 18m, with O2 deco at 6m as needed. . .

With the scooter off and stowed, all it took was three hard frog kicks into the current at 80m depth [in the video link above, observe the current impacting the divers & how little headway they make with strong frog kicks], and I was instantly overcome with a narcotic CO2 hit: Hyperventilation & difficulty with work-of-breathing the regulator, quickly deteriorating into dyspnea & cognitive confusion/delirium. In the dim ambient light, the only thing I was able to perceive was my Petrel Computer flashing an expected extreme PPO2 Warning prompt of 1.9, and it took a few minutes focused concentration not to panic, just to hang onto a rig structure support beam and try to regain a nominal breathing rate & clear head before starting the ascent solely using the scooter. Not at all pleasant and I don't want to do that again. . . (Note: Elevated CO2 blood levels also increases the chance of hyperoxic/Ox-Tox seizures.)

The point is that a Deep Air bounce dive to extreme depth can be treacherous enough even if reasonably planned and prepared as a solo technical dive with the aid of a scooter above . . .On single tank however, any other emergent contingency at those depths (i.g. equipment problems; buoyancy difficulties; breathing gas leaks; medical problems etc.) along with the CO2 poisoning & impairment will most likely overwhelm the diver and result in tragedy. .

 

[high/baric]

The best dive I have done was at 40m on air. I'm pretty sure there was a wreck. Man, that was a sweet dive...

 

[rjack321]

We had a local diver who enjoyed being narced for years. He did a lot of solo 50 to 60m stuff on air for the joy of it. I don't think he went much below 60m/200ft. This was about 4 years ago.

One day he passed out at depth. Somehow his reg didn't fall out of his mouth and he regained consciousness fairy shallow on ascent as his doubles got light. He ended up with a large deco obligation that got mostly blown. A local passenger ferry managed to pull him from the water and get him to EMS before he lost consciousness again. After a bunch of chamber rides he still has permanent nerve damage, mostly to his vision (the optic nerve is fairly sensitive to DCS). He lost his job as a firefighter and remains on permanent disability. And can't dive anymore.