TDI TRIMIX DIVER and deep air

[sharknutz]

But no, you cannot adapt to narcoses, you can learn how it feels, so you know better what to do. But the shape of the day will be the biggest reason for narcoses or not.

Awesome write up, from what I remember you actually had Tom Mount as an instructor? I'm inclined to agree that water temp, conditions, and how a person is feeling on that given day play a large role in the level of narcosis.

 

[Germie]

A way to react better on narcoses has to do with the skills of a diver. If you trained a skill that way that you dont need to think about it, you will be able to react better on narcoses then if you just mastered a skill, but are not well trained. A skill that needs attention to perform will ask more concentration and causes more stress. So with narcoses a higher risk. But that is no adaption in my eyes. Some say if you do deep air dives on a regular basis you will get less narcoses, but there is no proof that this is true. Only a better trained diver will longer be able to perform skills like using a reel.

Also co2 is a contributing factor to narcoses. So with air it is not only the n2, and po2, but also the gasdensity.
And if you work under water, more co2 is produced, so a higher risk.
It is not only nitrogennarcoses, but nowadays also called inert gasnarcoses and this covers also co2. The exact mechanism is still not known.

 

[tomfcrist]

For those interested in actual narcosis research. Barry Fowler. It’s old, but has some critical questioning concerning adaptation to narcosis over multiple exposures.

https://pdfs.xray-mag.com/articles/Tech_aquaCORPS4_45_locked.pdf

 

[sharknutz]

For those interested in actual narcosis research. Barry Fowler. It’s old, but has some critical questioning concerning adaptation to narcosis over multiple exposures.

https://pdfs.xray-mag.com/articles/Tech_aquaCORPS4_45_locked.pdf

Thank you for sharing, these rare gems don't get shared enough in my opinion! The results seem similar to Mount/Milner. Adaptation is a farse, but slow and focused actions can be accomplished even at some pretty extreme depths without mix. Especially, if you're familiar with the actions that need to be accomplished.

 

[Aura]

https://pdfs.xray-mag.com/articles/Tech_aquaCORPS4_45_locked.pdf

Good article, thanks for sharing. It seems to be aimed at people who need to perform tasks at depth where narcosis cannot be avoided though, which imo is rather unrelated to someone who decides to do deep air dives for recreational purposes.

This is entirely based on my personal experience with the local deep air divers, but they generally deny being affected by narcosis at all (the typical thing they say is that they have developed immunity). I've seen how they perform on dives deeper than 50m, and they are very clearly affected. These are dives in cold, dark water in northern Europe, I've been told that narcosis affects people significantly less in tropical swimming pool conditions. But either these people simply don't realize how impaired they are, or they're too macho and arrogant to admit it.

So it seems a bit odd to me that someone would want to do a trimix course, learn how to "correctly" dive deep, and then proceed to do it with air anyway. I can understand wanting to be covered by insurance, but the entire mindset of deep air divers is, as far as I've seen so far, deeply rooted in the belief that nothing bad can happen to me.

 

[Celt]

Divers making deep air dives don’t get overly worried about narcosis, it’s just something that has to be dealt with. Divers not making deep air dives get all in a twist about narcosis.

 

[Germie]

The main reason to dive deep air are the helium prices or availability.

 

[boulderjohn]

The main reason to dive deep air are the helium prices or availability.

One of the reasons I stopped teaching was the availability of helium. I had to work very hard to find enough to finish off my last trimix student.

 

[Celt]

The main reason to dive deep air are the helium prices or availability.

Another reason for us was with a handy compressor you had an endless supply of cheap gas. Not just for breathing but lifting bags and air tools.