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View Full Version : suit inflation: air or argon..?



Dave Lev
20-03-2013, 01:57 AM
Regarding this article:
Why Argon? (http://www.decompression.org/maiken/Why_Argon.htm)


There may be psychological components to a diver's perception of warmth, where the use of argon initiates a positive feedback loop: "I'm using argon, so I must be warm...." But beyond these subjective aspects, the objective numbers in Table I show that argon could improve diver insulation by up to 50% compared to air. In reality, the full performance of argon is compromised by the conductivity of the diver's undergarments and the presence of gases in the diver's dress. ...uhm, that's air and water vapor.... So, in the field, argon's improvement of insulation will therefore be somewhat less than 33% maximum theoretical advantage predicted in Table I --perhaps in the 10-20% range.

Assuming that avoiding helium in the drysuit is a given; few OC trimix divers wouldn't want to feed backgas into their drysuit in order to save the cost of an independant suit inflation cylinder.

But how much hassle is it to get argon fills for what seems to be little theoretical benefit..? (Especially if you fart a lot on the dive?!) Do you just use air in the suit inflation cylinder..?

Garf
20-03-2013, 02:34 AM
Done about 10 dives with Argon and god only knows how many with just air. I was never able to tell the difference. I think you'd actually have to flush the suit several times to see an measurable benefit anyway. It's expensive and it's difficult to get hold of. I would almost universally people just air unless they have Argon handy or cheap.

JPTaylor
20-03-2013, 06:02 AM
It's expensive and it's difficult to get hold of. I would almost universally people just air ...

Amuses me the way folks refer to them as "Argon Bottles" rather than "Suit Inflation Bottles", when they almost never have Argon in them :)

Major Clanger
20-03-2013, 09:37 AM
Amuses me the way folks refer to them as "Argon Bottles" rather than "Suit Inflation Bottles", when they almost never have Argon in them :)

Mine's an Oxycheck Analyzer Calibration Bottle.

Woz
20-03-2013, 09:52 AM
Argon's free if you have a TIG welder.

neilh
20-03-2013, 11:30 AM
Mine has backgas in it - providing I'm not diving mix.

I did dally with argon a few years back and while I thought it was a bit warmer it was a royal pain to get hold of and not significantly different to air/nitrox to justify.

...now I've got a heated vest :)

Dave Lev
20-03-2013, 04:11 PM
Thanks, chaps. About what I thought. Cheers.

Scuba steve
21-03-2013, 09:41 AM
I used air . But then i ditched the extra bottle and just connect off my 50% :punch:

Yes yesi know im going to die :grin:

notdeadyet
21-03-2013, 09:53 AM
Argon... Waste of time.

Apart from anything else I won't waste space with an unbreathable gas. I use a 3 of air for my suit which I've used to bail out from 40m on.

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Scuba steve
21-03-2013, 10:06 AM
Personally i wouldnt use air as part of a bail out plan for OC trimix

Hangin
07-10-2013, 09:04 PM
Changing the subject slightly where do you guys mount your suit cylinder on the back plate or on your cylinder. I have manifolded twin 12s.

The Duck
07-10-2013, 09:52 PM
Mine's a 1.5ltr ali & I put it on the backplate.

Whilst I've never had a problem with it there some people find it gets in the way - I suppose that it depeds upon your body shape.

witchieblackcat
07-10-2013, 10:40 PM
Changing the subject slightly where do you guys mount your suit cylinder on the back plate or on your cylinder. I have manifolded twin 12s.

I use a similar set-up to you. I have a 1l steel suit inflate which I attach to my backplate behind my left arm with a couple of straps. It's exactly like this one: http://www.divelife.co.uk/scuba-manufacturers/Halcyon/2359/Halcyon-1lt-Steel-Suit-Inflation-System

You do have to be careful where you mount it. Too high and it'll be a right pain and possibly stop your shoulder doing a shut down and too low digs in to your hip. If you have to go lower though.

nigel hewitt
08-10-2013, 06:22 AM
Wooo an argon thread. (so I wasn't here when it started)

Argon is more insulating, about half as much again, but wearing an extra layer of thermals is too.

I use it because I have it and I only notice a difference an a long dive. However what you are doing is making things easier for one of the regulation systems of your body. You can stay warm but argon means you need to burn less fuel to do it. On a long dive that is less blood sugar drop so after an hour or so dangling on a string après deep wreck the cold doesn't begin to seep into your bones quite as badly. It's difficult to tell unless you are doing several back to back and you can't top up the argon for some.

Flushes are just argon in argon out. What you need to do is make the suit squeeze up on the surface after you splash in but before you go down the shot, that's dump wide open, arms down and shake it all about until you feel that shrink wrapped feeling we all hate, then descend doing the usual suit adjust. It's only argon in your undersuit that works for you. Also it's a waste on a shallow dive as it doesn't get in where it counts
If you don't do that you are still on air close in and, surprise, surprise, you don't feel much different.

Hot Totty
08-10-2013, 07:19 AM
Argon's free if you have a TIG welder.

Not technically true, either your companies paying for it (theft) or , if its your company, your defrauding the tax man - :p of coarse woz being a pillar of the community wouldn't be doing either of these :shake:

BenL
08-10-2013, 07:42 AM
Whether or not the Argon is paid for, is it really required these days? Undersuit tech has improved drastically in the last few years. Heated vest, anyone?

Defiance Charters
08-10-2013, 09:38 AM
Good points for Argon
1) The specific heat capacity of Argon is approx 20.8 j/mol/k against nitrogen and oxygen which are both about 29 j/mol/k.
Meaning that it takes less energy from your body to heat up the Argon in the suit or conversely warm air in your suit from the surface will have more heat in it and will take longer to cool.

2) The thermal conductivity of Argon is approx 17x10-3 W/m/k against nitrogen and oxygen around 26x10-3 W/m/k. So Argon does give some benefit in terms of thermal conduction. However, how much this is relevant when the neoprene in the suit is about 54x10-3W/m/k and of course the undersuit.

Down side for Argon
1) More expensive than Nitrogen/oxygen mixes

2) Less availability

3) Requires additional equipment and so greater stress loading

Other considerations
The greatest heat loss from a diver is through the air breathed. So buy a rebreather ;) Alternatively much more simple heat preserving options such as insulating cuffs over the forearms where there is large heat-loss (ref: Fourth Element artic expedition)

Lastly consider the introduction of an inert gas into your suit. Argon is about 2.5 times more soluble than Nitrogen and will diffuse through the skin into the body. as there will now be a large pressure differential between the suit gas and your body. Argon being a large molecule will not travel that quickly to the blood supply where it will travel around the body and be breathed out. So this then asks the question of how quickly the argon can be removed on ascent. The suit remains pressurised with Argon so the pressure differential back into the suit may not be that high. So if the predominant removal method is through the blood stream, and the Argon is mainly in the areas of poor blood flow due to cold, then it is possible that the use of argon may be a contributory factor to dives with extended underwater exposures. However, this is all theory and little scientific evidence to substantiate it. If true then using a nitrox mix in the suit would be preferable. In any case using nitrox in the suit will increase the nitrogen gas gradient across the skin.

Personally, I use air or Nitrox in my suit up to 60% O2. Not specifically for this reason, but it is what is available in my stages and I am too tight to buy yet another cylinder of limited volume. Likewise dives using 10/50 diluent in the suit has also been known.

Hangin
08-10-2013, 05:55 PM
Mine's a 1.5ltr ali & I put it on the backplate.

Whilst I've never had a problem with it there some people find it gets in the way - I suppose that it depeds upon your body shape.

Thanks guys
I have the straps for the back plate so I'll try that first and see how I get on.

notdeadyet
08-10-2013, 06:56 PM
Likewise dives using 10/50 diluent in the suit has also been known.

I've used mix a few times and never found it unmanageably cold. I used to use 17/20 quite regularly in the Clyde and ran my suit from backgas. Just wear an extra layer. Don't blow it in all at once either. I did end up spunking a 10/70 mix on a shallow cave dive (long story) where I couldn't get through a restriction with a suit bottle on. Water was about 7 deg, that was noticeably cold, kind of on a par with doing the same dive in a wetsuit.

On the other hand, spending an hour or two pickled in helium may or may not be a great idea.

Iain Smith
08-10-2013, 07:10 PM
I've used mix a few times and never found it unmanageably cold. I used to use 17/20 quite regularly in the Clyde and ran my suit from backgas.

Hmmm...the Scottish diver's dilemma: spend money up front on a suit inflation system or waste expensive helium during a dive...

I.

Richard_Severn
08-10-2013, 07:19 PM
Hmmm...the Scottish diver's dilemma: spend money up front on a suit inflation system or waste expensive helium during a dive...

I.

I wish I could like that

James-S
08-10-2013, 09:21 PM
Suit inflate system? Is that another name for a deco stage? ;)

The Duck
08-10-2013, 11:57 PM
Suit inflate system? Is that another name for a deco stage? ;)

Some peoples quite possibly. Mine, no chance as you can't get gas out of a cylinder that's turned off (unless the deco gas is breathable on the botton in which case it's a 'bottom stage' or deep bailout) :p

Major Clanger
09-10-2013, 06:14 AM
Hmmm...the Scottish diver's dilemma: spend money up front on a suit inflation system or waste expensive helium during a dive...

I.

But think of the pizza you'll get in the chamber after using helium suit inflate.







Sent from my ivory tower using Tapatalk

notdeadyet
09-10-2013, 07:01 AM
But think of the pizza you'll get in the chamber after using helium

I've only been in Murrayfield and all I got was a packet of digestives. Not even chocolate. Mind you, you get 24 hours in a private room in the BUPA bit. Room service, private bog and cable tv.


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Scimitar Diving
09-10-2013, 07:07 AM
We used to fill argon suit bottles. In five seasons I can probably count the amount of fills we've done on two hands. Having tried it a couple of times, I couldn't tell the difference from air. I suspect it was a bit of a fashion thing a few seasons ago.

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smudger
09-10-2013, 07:53 AM
But on the whole it did allow you to attach a cool green cylinder to your kit with Argon witten on it!!
I bought one 2nd hand and filled it with a whip form oh yes a 12lt filled with air!!
nothing said Tech more than Black and green!!!:envy:
Still I sold it for a higher price than I bought it. So a cheap lesson for me.
But at least it was smaller than some cylinders that people at the time were using!!:nod:

edward
09-10-2013, 09:25 AM
My nice black 1l ali has never seen anything other than air.

notdeadyet
09-10-2013, 09:43 AM
I did some diving with a Norwegian group a few years ago who were using welding shield gas. They'd played about with different flavours as the Ar/Co2 mixes were a hell of a lot cheaper than pure Ar. They found one with 8-10%'ish CO2 that worked well, anything above gave very sore skin. I remember one guy saying he liked the feeling of carbonic acid on his skin as it made him feel a bit warmer.

paulnlowry
09-10-2013, 09:48 AM
Always used air to date.

Woz
09-10-2013, 10:04 AM
I did some diving with a Norwegian group a few years ago who were using welding shield gas. They'd played about with different flavours as the Ar/Co2 mixes were a hell of a lot cheaper than pure Ar. They found one with 8-10%'ish CO2 that worked well, anything above gave very sore skin. I remember one guy saying he liked the feeling of carbonic acid on his skin as it made him feel a bit warmer.

Our TIG uses neat Ar. Handy

Foggy
09-10-2013, 01:43 PM
.................I remember one guy saying he liked the feeling of carbonic acid on his skin as it made him feel a bit warmer.

How does that work? - the CO2 would react with his sweat (wicked away into his under suit) to form carbonic acid, which in turn would react with said under suit (dissolve it), both reactions giving heat of reaction and his sore skin was hypersensitised to heat.....;) ;)

notdeadyet
09-10-2013, 01:53 PM
How does that work? - the CO2 would react with his sweat (wicked away into his under suit) to form carbonic acid, which in turn would react with said under suit (dissolve it), both reactions giving heat of reaction and his sore skin was hypersensitised to heat.....;) ;)

My undersuits seems to dissolve quite happily on their own... I once thought I was having skin bends which suddenly stopped after I washed my thermals.

gobfish1
09-10-2013, 09:30 PM
Lol