Obtaining Oxygen

[wetfox]

My Airgas account expired and I am encountering difficulty getting it restarted for medical-grade oxygen. My O2 training certs expired and I have to take the DAN O2 class over again to satisfy Airgas. Not a problem, just a hassle--I used to teach it.
I could buy Aviator Grade with no problem, but it is expensive. I could buy Industrial Grade (cheaper than medical grade). I know there is no difference in the actual oxygen between medical and industrial grades--just the protocol on how to treat the cylinders (three evacuations versus one during filling) and some paperwork issues associated with tracking medical grade lot numbers. So here is my question. Does anyone have any experience or advice about using industrial grade in deco gas mixes?

 

[tbone1004]

are you selling it or just using it for yourself? If selling it, look into the liability of selling industrial gas as a breathing gas. If using for yourself, I wouldn't worry about it

 

[68raggtop]

Aviator and medical are both USP and tracked as I understand it. Aviator is around $15 a T higher than welding grade where I get it from. I prefer to have the Aviator for that small difference, but have used welding grade on many occasions and would again if can't get Aviator.

 

[rjack321]

Been using "industrial" O2 and helium (which is 5 nines grade) for about a decade now. Never had a problem.

For my supplier (who actually is a retailer for wholesale airgas) the differences are 1) the paper trail 2) medical grade supply bottles are triple vacuumed before refilling while industrial are only vacuumed once. They don't sell an aviator grade (as its a welding shop and I don't wanna ask)

 

[Germie]

Dived on industrial oxygen and medical oxygen. Both without problems. But if you are a shop or selling it, it must be 'divegrade', so no industrial oxygen.

 

[rjack321]

Dived on industrial oxygen and medical oxygen. Both without problems. But if you are a shop or selling it, it must be 'divegrade', so no industrial oxygen.

In this country industrial helium is actually cleaner than medical grade. Medical grade helium is typically only 99.9% whereas analytical grade can be as high as 99.9999% He. It really just has a higher purity specification, but the reality is that its all the same gas. There is no gas plant making sorta dirty helium and another making purer helium.

The only thing you really need to be concerned about is o2 made via an oxygen generator in remote places. Like the south pacific. Its about 98% oxygen which is great, the problem is for rebreather use the ~2% balance is argon which can accumulate in the loop. For open circuit use the ~2% argon is not a problem at 20ft/6m and is vastly diluted by air in any nitrox or trimix made from the oxygen generator made O2.

 

[tbone1004]

even in a ccr, the argon that's in there can be flushed out with a dil flush every few minutes, you just have to be aware of it