Lowes has oxygen

SiscoKid

You can rent welding gas 02 bottles from any Welding supplies. I bought an Aviation 02 from them, I just exchange from them when I need more. Its about $18.00 exchange

Gill Envy

It's not a matter of money. is it not true that medical grade has a high moisture content, that is hard on steel tanks? My only experience with using welding oxygen was in indonesia where it was the only thing available. It turned out to be 99%... and we enjoyed it to the last drop.

It seems to me that in the past that aviation grade was preferable.

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Gill Envy

...Because I wasn't born with gills!
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Yankee Rebel

i am going to have to check praxair for O2... Airgas charges me $38 for the fill, $5 for hazmat fee, and a $1 inspection fee when i turn in a 250cuft bottle. id MUCH rather pay $16 for my O2 than $44... no idea if i got USP gas or not.. no sticker indicating it... it breaths fine.. about the only contanimates that i can think of thatd be in it would be inert gases. Acetelyne uses different connections than O2. id like to think that harmful gases do too.
one reason i have avoided Praxair so far is they had a nasty habit of swapping my buddys customer owned (smooth ring) bottles out for THEIR bottles with THEIR rings on them. he didnt catch it until afterwards... shouldnt be too hard to get it swapped back to customer owned.. but what a potential PITA...
my point there.. keep an eye on your rings when you swap bottles... having to deal with some overzealous ***** who "KNOWS" that they only swap out smooth ring bottles for smooth ring bottles, and if your bottle doesnt have a SMOOTH ring.. then its not customer owned...

now to give Praxair a try with an old bottle that needs to be swapped out and rehydro'd...see if theyll just accept it as is, or if they are gonna be difficult about it...


GREAT TIP ON LOWES AND O2!! for $20 ill check them out and see about grabbing a small bottle for torching with.. beats having to hook up my nice clean full 250 to some dirty torch regs and waste the gas and pressure.

Yankee Rebel

Yankee Rebel

false!
its the same O2 as whats in welding bottles, Medical bottles and Aviation bottles... the difference IF anything is in the fill techniques and the prices.

ask your local major gas supplier.. call them up and ask around.. tell them that youre going to be using the O2 for diving purposes.. explain you are completely certified to dive high FO2 gas mixes and to mix your own blends... and that youd heard that medical grade O2 had a higher moisture content... when the guy gets done chucklening.. ask him nicely to explain to you the differences.
years ago we went to a few gas suppliers until we found out the truth from one that took the time to explain things to us. he said hed be just as happy to take our money for the better grade gas.. but in the end.. we mixed ALOT of Nitrox with welding O2. we also used a fair amount of Medical Grade O2 for liability reasons...
truth of the matter is O2 is DRIER than the AIR you put in your SCUBA tanks in many cases..

the Oxyhackers Companion offers some good explanations as well.. call your gas suppliers and ask about the real differences tween the 3 grades.

for ME... regular old welding O2 is good enoughf or what I do. if any concerns or worries.. run the O2 over your PPO2 gauge and see what it reads.
now if i was responsible for anyone else using my gas... id probly kick out the extra money for Medical or Aviation grade just to make life harder on the lawyers if something happened..

Yankee Rebel

p.s. we ALL know that moisture under high pressure in the presence of elevated O2 content rusts the dog crap out of our SCUBA tanks... consider how often those STEEL O2 cylinders are filled, refilled.. refilled, etc and how long they can sit with 2200-2500PSI in them... 10 year hydro's!!! TEN YEARS without the valves being spun off and anyone even LOOKING in there...

RebreatherNut

So, what is new with Praxair? Are they selling now to all divers or just shops.
When I went to our local Praxair here in town, about 7 weeks ago, they wouldn't sell me Medical Grade, only for Welding. However, the guy said if I can produce a DAN O2 Provider Cert, then he would sell me Med. Grade O2.

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rigdiver

From Praxair's website you must show a blending cert and proof of logbook kept. Wanna be a shop? Go get a business license. Cale can help I talked with Praxair at length at DEMA. Ask for "Diver Grade." The company people I talked with very much seemed like they wanted to help. I could write a book on the problems I've had with gas suppliers and I owned a legitimate store with all the certs you could possibly ask for. I showed Air Liquide the federal law(obtained from DAN.) Their answer was "they'd have to check with the state FDA." I got em a prescription. Then they said they were not "pharmacists" Never mind they asked for the prescription in the first place. I got a little pissed when they were still refusing after I met all their demands. They finally caved in and were selling me 337 cu ft T's for $16.00USD. It was labelled 'USP" Medical Grade. It did give customers piece of mind.

babar

My understanding is that, in general, welding, aviation, and medical oxygen are all the same.

They do have different standards, but in most cases, there's no practical difference.

Never tell a gas supplier you will be using the gas to dive with. That's the surest way to be shown the door.

Buy welding gas, no one will ever check your credentials, or ask for a prescription.

And this is from someone who can write a prescription for it, if need be. And who has an almost infinate supply of medical oxygen available for 'borrowing' at work every day.


PS lowes has argon bottles too

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Babar
Evolution Plus
Sport kiss

mempilot

It seems there are two points that get confused when talking about gas suppliers:

1. Gas quality
2. Fill procedures

The first deals with purity and moisture content. It sounds like in many cases, med, weld, and aviator all come from the same storage bank.

The second deals with quality control in the filling process. Are the returns vacuumed and such?

Gasoline is the same way to some extent. Most of your gas stations get their base gasoline from the same distribution point. When it goes into the truck, it is blended with their proprietary additives. Is the gas better at one station to the next? Well, probably not the base gas, but the additives might make some marginal difference.

In the case of O2, the gas comes from the same point, but to get the stamp, the process must be higher quality. I'm guessing, some gas suppliers are just bypassing this step since they know their customers and what the bottles were used for. By selling to an individual, they lose that control.

ie. bottle delivered to hospital A to be used on a hyperbaric chamber probably doesn't need to be vacuumed for replacement back to hopital A or even B for that matter. Should it? Good answer is probably yes. Do all of them follow the guidelines? Probably not. The less individuals they have to deal with, the better for them.

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Eric Stadtmueller, otherwise known as, MEM "Da Pilot"

Joe

I agree 100% !!!

IMO, the worst risk is with He. When the gas companies run out of bottles they take other inert gas bottles and paint them. This means you could conceivably have a bottle with a mix of He and Ar or N2 or whatever should the employee doing the filling forget to empty the bottle and vacuum it. I only use UHP or HP for that reason.

SiscoKid

Welding 02 if you don't own the bottle and you exchange, the last person to use that bottle for cutting may have used all the 02 in it and left the valve open for a day or so for some reason. Now you have a contaminated 02 bottle for breathing not for cutting they may or may not pull a vacuum on that bottle when pump. Aviation 02 is not that hard to get for the deference.