So I took your advice on overhead diving...

[lamont]

Ah, good thinking. I'm going w/ the 40 for now, but am buying an identical reg set that I can migrate to my doubles when I get them, then the 40 can be used for a stage bottle or something down the line. What is the benefit of using Argon vs. air for your drysuit inflation? I've seen this configuration but wasn't sure why it is used?

Helium has a higher thermal conductivity than air, so if you use it for drysuit inflation off your backgas it will make you very cold. So, you need to add a drysuit inflation bottle in order to dive helium mixes. Since you are adding an extra bottle for drysuit inflation, you can put Argon in there which has a lower thermal conductivity than air does. To really get the benefit from Argon you should also do a suit flush or two at the surface.

 

[battles2a5]

Helium has a higher thermal conductivity than air, so if you use it for drysuit inflation off your backgas it will make you very cold. So, you need to add a drysuit inflation bottle in order to dive helium mixes. Since you are adding an extra bottle for drysuit inflation, you can put Argon in there which has a lower thermal conductivity than air does. To really get the benefit from Argon you should also do a suit flush or two at the surface.

Thanks Lamont, that makes sense. Very interesting.