Argon in decogas?

[Jaap]

Hi all

I have a vague memory that I read a thread some year ago about some guy who used 80/20-O2/Ar as one of his deco gases in order to off gas nitrogen faster during a trimix dive.

Does anybody know if this is true?

I understand that the use of some fraction of Ar at depth would be very bad due to the increase in narcosis and the greater solubility and more limited knowledge of having argon in the mix making the decompression longer and more dangerous.

But to substitue some of the nitrogen on the shallower stops could maybe work (?), where on gassing of Ar would be limited and the increased narcosis of having Ar in the gas would be of little to no effect.

I would not like to be the first to try, but does anyone know if Ar has been used in decompressiongases?

 

[SDAnderson]

Given human nature, someone has tried Ar as a breathing gas, the results weren't advantageous:

• It's highly narcotic, generally accepted as a bad thing underwater.
• It's too heavy, which makes it hard work to breath under pressure.
• It's too expensive, even more so than He.

He seems to be the most effective and increasingly divers are using Heliox50 for their 70 foot bottle. It doesn't make sense to me to use anything but O2 at the 20 foot stop, though, you're just complicating the issue without benefit.

 

[Jaap]

Yes I'm sure to agree with you that increasing the He-content seems to be the trend to a safer dive/deco and that Ar in any form of breathing gas would probably not be a good idea.

But that was not my question.

I was asking if someone knows of someone who actually tried using Ar in a shallow decomix where the ongassing would be limited and WOB and narcosis a non issue.

I don't know where you buy your Ar but my Argon cost just about the same as my O2 which is about one third of the price of He.

I'm not advocating the use of Ar for breathing I just want to know if someone has tried it for this special purpose. I don't buy this talk about, yes someone has already tried all the stupid things one can come up with. If I belived in that I would quit my research and go to work at Burger King

Happy weekend

Given human nature, someone has tried Ar as a breathing gas, the results weren't advantageous:

• It's highly narcotic, generally accepted as a bad thing underwater.
• It's too heavy, which makes it hard work to breath under pressure.
• It's too expensive, even more so than He.

He seems to be the most effective and increasingly divers are using Heliox50 for their 70 foot bottle. It doesn't make sense to me to use anything but O2 at the 20 foot stop, though, you're just complicating the issue without benefit.

 

[Charlie99]

Why is Argon not used? has a pretty good discussion of the pros and many cons of argon.

One of the posts mentions Jim Bowden's Zacaton project.

 

[dtdiver]

to impress you with argon's narcotic capability, anesthesiology researchers are experimenting wiith the use of argon as an anesthetic!!

and this is at atmospheric partial pressures.
and if you consider that you need at a minimum 21% oxygen that leaves you with about 70% argon mixes as being anesthetic.
talk about impairing judgement....

at least when you get bent it won't hurt so much.

but i can't recall the dose/response as to lower concentrations. but, i think it would be reasonable to extrapolate from percentages to partial pressures.

so, albeit you have a lower absolute percent in your tank, at higher pressures at depth it will impair you just like a higher concentration would at sea level.

dt

i will try to dig up the references if anyone is interested.

 

[IndigoBlue]

A good dilutent gas is non-narcotic. Argon is very narcotic.

A good dilutent gas is light weight and easy to breathe. Argon is very dense and difficult to breathe.

The only good candidates for use as a dilutent are Helium and Neon.

Helium conducts heat away from the body more than Neon, however Neon is extremely expensive, compared to Helium.

That is why we are left with helium.

Argon works well in light bulbs and for inflating your drysuit from a small argon bottle. Definitely not for breathing as a dilutent.

 

[Bob3]

Ya left out hydrogen...

 

[DepartureDiver]

argon is also very soluble.