I read a study report done by the Navy that said that in divers that they tested using argon made no appreciable difference in the comfort of the diver. They implied that it may be a placebo effect on divers using argon. As placebos go, I am more than willing to take it. For argon to be effective, placebo or not, the suit needs to be flushed with argon a few times, not just a couple of squirts on top of the air that is in the suit after it is sealed.
JoelW
Yeah, I've heard that methane works pretty well too. The big advantage here is that is comes into your suit at 98.6 degrees. Nice and warm. Probably not going to help any in keeping your undergarments smelling fresh though
I konw the navy did a test with argon, but as far as I know, you don't notice the positive effects of Argon until you're not using it anymore. Like going from air to argon and back, you'd notice after you went back to air. That does seem to imply a placebo tendency, or minimal effect, but I'm with Joel in that anything that even makes me think that I'm warmer is a good thing.
I thought the the test of Argon vs air in the drysuit was a draw with air used as the breathing gas, but they felt that the greater density of argon while using HE mix would be benificial. I don't think they found anyone to volunteer for the methane inflation method, but give them a grant and I'm sure it will happen.
If you want a rigorous explanation regarding Ar as a drysuit inflation gas, go to the following link. There are better gasses than Ar but they are less available and much more expensive.
John J