200' on air for 5 min bottom time?

[Ste Wart]

And most people that are opposed to suicide never shot themselves in the head.. so what?

How is that a comparison? We're talking about diving. Have you dived either deep air or trimix? I doubt it.

 

[DCBC]

I have many fond memories of the deep air dives, and of the adventures...but the reality was, when George got us to try trimix in around 96, our first dive on it on the RB Johnson/Cory"n Chris, was different from any dive we had ever done on it before. Everything was easier...

I had the same experience Dan. I got into Deep-Air because I got tired of visiting Wrecks that were picked-over by other divers. I was 15, had been certified for 3 years, had logged a number of hours and wanted something more. Their wasn't any choice for recreational divers at that time, so it was Air. I suppose part of it was fueled by being a bit of an adventurer and feeling that I was bullet-proof (not an uncommon feeling for a young teenager). IGN was a hurdle that needed to be carefully overcome, so we planned the dive accordingly, took extra air and did the dive. None of us wanted to die, so we agreed to scrub the dive without question, if any member of the team elected to do so. With more experience, I found it became even more manageable.

When I was 17, I started to Cave Dive, assisting Dr. George Benjamin from Toronto, who was extending his underwater survey of the Blue Holes of South Bight (Andros) in 1971. George played host to Jacques Cousteau the previous year, but wanted to do more exploration. We used Deep-Air (Doubles) to depths of 300 FSW.

My first experience with Helium occurred later that year when I joined the Navy. I too felt the benefits of clarity of thought. It made diving easier, but at the same time, it tamed the tiger for me a bit and Helium does have some disadvantages. Since then, I've been involved in several aspects of Commercial Diving, including deep saturation (in excess of 1000 FSW).

I use a number of gases. Sometimes however, they're not always available where I want to dive. Air is available and if the dive is within my safe diving envelope, I do the dive. I'm glad I've learned how to do this safely and don't begrudge the time it took me to go through the process.

Personally, I've always been a bit of a risk taker. At the same time, I don't believe in taking foolish risks or acting in a reckless manner. It use to be that people who took-up SCUBA were in reasonably good condition and had an adventurous spirit. Today I think that this is less true. Any type of technical diving (TD) increases risk. I can't believe that people that take up one aspect of TD brand something else as unsafe. Some people throw stones at Deep-Air, but at the same time elect to do a dive into a Cave/Wreck on Trimix thereby accepting an increased level of risk (that they don't need to take). They choose to do the dive anyway. The choice is after all their's to make.

Any uncontaminated gas you breath doesn't kill you. It's how you do the dive with that gas that can cause a problem. Deep-Air is like ear equalization. If it's not working for you, scrub the dive. Like all aspects of TD, you're best to be trained how and proceed carefully.

 

[Tigerman]

How is that a comparison? We're talking about diving. Have you dived either deep air or trimix? I doubt it.

The point is, does it matter?
You KNOW shooting yourself in the face is a bad idea. You KNOW getting intoxicated before driving is a bad idea.
We KNOW FOR A FACT that both nitrogen and oxygen is narcotic. You dont need to dive to 250 feet to find out for yourself that you get narced, its a fact that you do.
You can get used to performing tasks like driving while youre drunk, but that dont mean if something unforseen happens, youll be able to correct for it.

 

[lamont]

You of course are entitled to your opinion Lamont. My experience however, has caused me to come to a different conclusion. Adaptation does in-fact occur.

I'm not claiming it doesn't occur. I've noticed adaptation to narcosis (at shallower depths) in myself.

I'm pointing at a case of someone who was clearly adapted, and had a nearly fatal outcome. Adaptation is just a rationalization to keep playing russian roulette.

---------- Post added June 2nd, 2013 at 11:32 AM ----------

He had hundreds of those dives that didn't nearly kill him. So, what was different on the ONE dive that nearly killed him?

Phase of the moon.

He'd done that exact dive before at the same site many times, its an easy site, so conditions weren't any different. This time his number nearly came up though.

---------- Post added June 2nd, 2013 at 11:37 AM ----------

Unlike Lamont I am quite ready to believe people can adapt to the impairment...

Just stating this again, I've noticed adaptation to narcosis even at 30m-40m in myself. I haven't stated anywhere that I don't think narcosis adaptation doesn't exist. I just think its a rationalization along the lines of people who drive drunk and think they've got enough drunk driving experience that they can handle it better than the average person that the laws are written for...

 

[flots am]

I haven't stated anywhere that I don't think narcosis adaptation doesn't exist. I just think its a rationalization along the lines of people who drive drunk and think they've got enough drunk driving experience that they can handle it better than the average person that the laws are written for...

I believe adaptation exists, but only as far as people who get narced often enough just stop recognizing it as "something bad". It's not an adaptation as in "I can still perform normally."

One of my old bosses used to get hammered every night and brag the next day that "it's a good thing his truck knew the way home". Except that every now and then he'd wake up in a ditch with a wrecked truck.

Underwater is less forgiving that a ditch and a big truck with airbags.

flots

 

[Dr. Lecter]

Phase of the moon.

He'd done that exact dive before at the same site many times, its an easy site, so conditions weren't any different. This time his number nearly came up though.

Was it the narcosis, or was it the diver/diver's complacency?

 

[Tigerman]

Was it the narcosis, or was it the diver/diver's complacency?

If it was the divers complacency, was that complacency caused by the narc?

 

[Garth]

So the title of the original post gives divers the wrong idea but I will say that a healthy respect can come from a bad experience. If someone is stupid enough to dive to 200ft for 5 min they wouldn't truly enjoy it so I certainly don't envy them.

I will however state that I did dive to 212ft on air for 15 minutes with 100% and 50% decompression cylinders. I had enough for me plus one diver in addition to 2 other divers having the same amount of gas.

Ridiculous. I had the time of my life and seriously wrote, "you fu$&'n guys" on my slate in the most happiest way. The best part was at about 20 minutes into decompression I realized I had wrote it...

I'm on a quest to do it safely now. It only took me once to realize that although it feels great to be narced that its not something that promotes longevity.

So I'm sure it has been said a good bit already but the progression would be open water, advanced open water, time, many dives, adv nitrox & deco procedures, time, more dives, recreational trimix and well then you could technically do it safer but for 5 mins what's the point.

 

[Kevrumbo]

If you're in warm tropical 27deg C waters, no current, good viz, on an external easy tour of a wreck (like in Truk Lagoon), you can cognitively accommodate to deep air. You have trained muscle memory to handle most contingencies albeit you may be slower to process, problem solve and react . . .so you strategically mitigate your activities to avoid potential tactical overload in an emergency situation --i.g. don't penetrate the wreck; don't physically exert yourself to CO2 retention levels & starting the vicious dark narc cycle; don't do any extensive computations on-the-fly to your deco schedule; go no deeper than 60m or ppO2 1.47 etc. --keep it all nice, easy and simple. . .

 

[Garth]

True. For my 212ft dive I was in 45-50 F waters a bit cold.

---------- Post added June 2nd, 2013 at 06:10 PM ----------

It certainly made me more narced and I also wouldn't plan on water temperature reducing narcosis although you do have a bit of a point.