Argon gas... How?

[100days-a-year]

Don,that's kinda what I meant in that with being insulated by dead air spaces the conduction would still conduce away more energy than the relative convection advantage argon would have.And I was assuming that argon and indeed He based back gasses will be drier than air and hence absorb more moisture enhancing evaporation.Be aware cold water diving is all theory to me as I live in Florida.I dive mix on occasion and it does feel much cooler in my mouth,throat and chest.

 

[Seadiver5]

After 2 months of diving in the Arctic last winter i am conviced that Argon does little or nothing to really help keep any diver warm.

I was as warm if not warmer diving in the Arctic without Argon than what I am diving in Seattle with Argon.

My personal feeling is that you should try better undergarments before wasting money on an argon system

Kevin Parkhurst
IDEA Instructor 3402

 

[Snowbear]

It works for me! I had to stop using it in the summer 'cause it was making me sweat in that 60F water!! Now that the temps are in the 30's I notice the difference. I really don't care if the scientists and expert experimenters say it's just a placebo - whatever - it works.

 

[DA Aquamaster]

Some people are missing the point here. Argon's theoretical advantage is only 33% under the ideal conditions of a truly "dry" (ie: no moisture from sweat, condensation etc) drysuit with nearly all the air flushed from the suit prior to the dive (ie: filled and burped twice). It's offers a slight advantage, not a magic solution to staying warm. It's not surprising that not a lot of difference is noted by some divers under real world operational conditions (although I still know several divers who swear by it.)

Personally I have a 2015psi 14 cu ft pony that I kept for argon use, but never used extensively due to limited availablity of fills pending the acquisition and assembly of the hardware needed to do my own fills. Then, while my overpriced thinsulate underwear was at the cleaners, I used a heavy pair of inexpensive "woolly bear" underwear that had come with another drysuit and found to my surprise that they were a lot warmer even without argon. They were a little bulkier and required a few more pounds of weight - but were much warmer.

My ultimate conclusion was that transfilling Argon was a pain even with a low pressure pony and while there is some potential advantage to argon (even if arguably mostly as a placebo) it is simpler just to add more insulation in the suit with thicker undergarments and stay with air. But if I were still getting cold on dives, I would consider using it just for that last 30% advantage it potentially offers over air. Besides I already own the damn tank, so why not?

 

[Bob3]

... Besides I already own the damn tank, so why not?

I have a wide assortment of small bottles, when diving commercially we were required to wear a bailout. When in very shallow "stand up" depth water I'd use a 6 cubic footer. On a fun dive one of the guys spotted it in my box & thought it was argon, said he always wanted to try it. I obliged (while not mentioning it was only air) & the lad commented after the dive how much warmer he'd been.
I didn't have the heart to tell him what was really in the thing. :tease:
Little bottles work well as a bailout if you're diving single tanks in shallow water (snorkel depth, about 60' or so) .

 

[The Iceni]

Seadiver5 once bubbled...
After 2 months of diving in the Arctic last winter i am conviced that Argon does little or nothing to really help keep any diver warm.

I was as warm if not warmer diving in the Arctic without Argon than what I am diving in Seattle with Argon.

My personal feeling is that you should try better undergarments before wasting money on an argon system

Kevin Parkhurst
IDEA Instructor 3402

On the nail, Kevin,

If you guys understood my last post you should realise that the diver's perception of "comfort" is not a good indicator of his environmental suit's efficiency.

In dry suit diving you are sealed in a bag so there is little or no heat loss from convection. At working tempertaure the "microenvironment" within the suit will have reached the steady state so there will effectively be no heat loss from evaporation.

This leaves us with conduction which is the single major controllable source of heat loss in dry suit diving (you can do very little about losses from the respiratory tree with open circuit).

The membrane offers little insulation so the important variable is the insulating properties of the undergarments worn. A string vest works on the surface because air is a poor conductor and the vest holds the outer jacket away from the skin.

Whe using Argon, all else being equal, as it's conductivity is 2/3 that of air, Nitox and oxygen when the suit is filled with Argon an undersuit of 2/3 the thickness will yield the same thermal efficiency as one filled with air. Or to put it another way, if the same undersuit is used with Argon it will be one and a half times as efficient. Whether this is necessary is the question.

The discussion about Thinsulate B is interesting. Water is a very efficient conductor c/w air so any undergarment that reduces condensation is to be recommended. I have dived with a leg full of water (after initally forgetting to close my pee zip when launching the RIB) and very cold I was too -and I suffered cramp in that leg! However I do not remember ever having to empty my suit of gallons of condensation accumulated during a dive. The inner surface of the membrane does indeed get damp from condensation (as with a bottle of cold beer) but a good undersuit prevents this from coming in direct contact with the skin.

Argon works but it is not essential since a 150% thicker undersuit will yield the same result (unless of course you fill it with helium).

Or have I missed something?

 

[SDAnderson]

Bob3 posted a link to the results of a study, Thermal insulation properties of argon used as a drysuit inflation gas, that seems to be definitive. The value of any argument, whether based upon personal experience or phsycial properties, would seem diminished in comparison to the results of this study. If you're interested in the subject (and what drysuit diver isn't?) then you should read the study - all of it.

Money graf:

"Uncontrolled observations from the 'technical' diving community claim superior thermal comfort when replacing air with argon as dry suit inflation gas during diving. The objective of the present experiment was to evaluate the effectiveness of argon compared to air during cold water diving. Body weight, urinary output, and rectal and skin temperatures were measured in six naval divers during the two dives to ~10 m for 60 min. Level of thermal comfort was reported. Dry suit gas was either argon or air, divers and scientists were blinded for gas identity. Urinary output was ~200 ml less (P < 0.05) during he air than the argon dives. Rectal and all skin temperatures decreased significantly in both groups during the dive but no difference was measured between argon and air dives. Thermal comfort was not different between the groups. Replacing the air with argon neither improves subjective impression of thermal comfort nor attenuates core or skin cooling during cold water diving to 10 meters of sea water for 60 minutes."(Emphasis added.)

Disputes with the results of this study are made, but they seem silly unless they somehow address the study. Annecdotal evidence and reductio ad absurdum arguments are interesting but less relevant.

That said, diving helium may well be a different thing altogether and when facing a long deco in cold water I want every possible advantage I can find - including any placebo effect. The power of voodoo may lie less in the shaking of a gourd than in the rattling of the knees, but that doesn't mean that it doesn't work. After an hour hanging in sub-40F water, I guarantee you that my knees (and everything else) are quivering, so I use argon when diving He mixes. Heck, I'd use peanut butter if I thought it would help. Otherwise, I'm going to save my money and use backgas.

Steven

 

[GDI]

:doctor:
Basically Argon being one of the basic gases used in diving does work for warmth. Argon has a much heavier molecular structure than some of the other gases. The absorbtion of Argon into the human body tissue is much slower. With the thermal conductivity characteristics Argon has shown to be a excellent insulator. Given that any gas will also increase it's iPP Argon appears to become an even greater thermal insulator (to some extent) at depth. As much as a inert gas as it is I would not attempt to breath it though.

We can also look at the narcotic levels of various gases.

Gas, Narcotic Level from least to most
Helium, 4.26, Least
Neon, 3.80
Hydrogen, 1.83
Nitrogen,1.00
ARGON, 0.43
Krypton, 0.14
Xenon,0.039, Most

 

[The Iceni]

Disputes with the results of this study are made, but they seem silly unless they somehow address the study.

That said, diving helium may well be a different thing altogether and when facing a long deco in cold water I want every possible advantage I can find - including any placebo effect. The power of voodoo may lie less in the shaking of a gourd than in the rattling of the knees, but that doesn't mean that it doesn't work. After an hour hanging in sub-40F water, I guarantee you that my knees (and everything else) are quivering, so I use argon when diving He mixes. Heck, I'd use peanut butter if I thought it would help. Otherwise, I'm going to save my money and use backgas.

Steven

Hi Steven,

I, for one, am not knocking this study but a one hour dive is by no means a long dive in the UK technical diving scene and as I think I made clear, measures of comfort and skin temperature are limited.

Until we restudy changes in metabolic rate we will not get the definitive answer. However, as I also posted, Argon has its place but need it not be employed on every dive.

I think we are in violent agreement! :fight:

 

[Rick Inman]

Thanks all for the great input.
Good news. On yesterday's dive, my argon gas DID feel warmer, even after reading all these posts! If I am simply a victim of the placebo effect, so be it. Fortunately, I have a tendency not to let the facts get in the way of my thinking.