When to go to Trimix?

[Rainer]

Adding helium REDUCES the density of the gas and thus the WOB.

 

[ScubaFeenD]

Trimix is a denser gas???? Could someone help me understand that? ('member, not trimix trained, here)

Sorry, i didnt make it clear that the more dense gas i was referring to is Air. I was saying that He is less dense than air so it reduces WOB because it is easier to move in and out of the lungs.

 

[Doppler]

Assuming one is trained in Advanced Nitrox and Decompression Procedures and Trimix (recreational or not) --

At what depth would you routinely prefer to use Trimix? and

At what range is either / or Trimix / Air / Nitrox?

I have read that some people dive air routinely to 200fsw, I have also seen that some people won't go below 100 fsw on air.

So, what is your personal range that you would use one or the other, and at what point would you absolutely not go deeper unless on Trimix?

Oh, yeah, and Why, Please?

JAX: here's the easy math; especially for diving in local waters here in the Great Lakes Basin (assuming OC).

Acceptable partial pressure of Nitrogen 3.1 bar
Acceptable partial pressure of Oxygen 1.2 bar

which equals 4.3 bar or 33 metres (whatever in friggin' feet I do not have a calculator).

which in turn means that below 33 metres, there is going to be a vacant partial pressure. The only gas we have to fill that void is helium.

OK, now let's get your ass in a helitrox or mix class. LOL

 

[Randy g]

Jax great thread! I am just starting down this road and there is ALOT of really good information here.

Thanks!!