Discharging an old oxy cylinder

[Gun Freak]

A while back I acquired a ~1 liter oxygen tank originally stamped with the year 1960 IIRC. It came with a gauge and regulator, and when I cracked the valve a little, the gauge read 1,500 psi. It's now been in my room for some months and I want to discharge it just for peace of mind and because I might be able to reuse it later on. I know about the dangers associated with oxygen so I wanted to make sure that I discharge the tank safely. Is there any certain precaution I should take when emptying it, or should I be ok just cracking the valve and letting it bleed out?

[Zeus]

>Light cigarette
>Open cylinder
>Collect underpants
>???
>Profit!


Seriously, barely open it away from any potential ignition source, where there's wind or a breeze and you'll be more than fine. I really wouldn't be too worried.

For those interested I have put a cigarette in an oxygen stream, and naturally it caught fire.

[Gun Freak]

For those interested I have put a cigarette in an oxygen stream, and naturally it caught fire.

A lit cigarette set the oxy stream ablaze, or the oxy stream set an unlit cigarette ablaze?

[MrCrowley]

I had wanted to do something similar a couple years ago. I asked a guy down at the local dive shop and he just said to stick it in the middle of a field, crack the valve, and give it a few hours. I was in a rural town so didn't have to worry about people interfering but I never got round to doing it. Not sure how I would go about it in a more populated area.

If it's been pressure tested recently and is up to spec, maybe a local workshop would take it off your hands to use it up and hand it back?

[Gun Freak]

Thanks Crowley, I think I'll take it over to the lake and let her rip. Slowly of course.

I don't think it's been stamped in at least 20 years, so the workshop thing ain't really an option. I re-checked and its originally stamped March '44, so I think it was used in the war. Came with a breathing mask also so maybe it was one of those things they used in a plane, or in a medical camp or something like that. Basically its pretty old haha, but if it's been holding 1.5kpsi for god knows how many years, it should be ok for some medium pressure applications.

[bravootome]

>Seriously, barely open it away from any potential ignition source, where there's wind or a breeze and you'll be more than fine. I really wouldn't be too worried.
For those interested I have put a cigarette in an oxygen stream, and naturally it caught fire.

he must keep it away from any oil source and any fats ....a cigarette has nothing to do. It was not the oxy burning it was the cigarette burning much faster .

[Zeus]

>Seriously, barely open it away from any potential ignition source, where there's wind or a breeze and you'll be more than fine. I really wouldn't be too worried.
For those interested I have put a cigarette in an oxygen stream, and naturally it caught fire.

he must keep it away from any oil source and any fats ....a cigarette has nothing to do. It was not the oxy burning it was the cigarette burning much faster .

Low pressure oxygen with no combustion source won't start a fire in contact with oils, I'd keep it away from some solvents in case of explosive peroxide formation (not a how to, a warning), but otherwise it'll be fine.

Naturally the lit cigarette caught fire(instead of glowing), that was implicit. You can set punk sticks from an ember to on fire easily too.

[Technician1002]

Be careful. The high velocity stream can cause impact ignition if the valve is very dirty. Do not clean it with any kind of flamable solvent. This ignition source has been the cause of several aluminum regulator fires. The older tank should have a brass valve. Brass does not seem to have the fire hazard of aluminum regulators and aluminum cylinders. Crack it slowly and leave it to bleed off. It should not take long. An older tank not subject to repeated filling should not have stress related issues, but it should be inspected for outside corrosion that could reduce the strength. Remember that once empty, the inside of the tank still contains 100% pure oxygen. It still has some hazard due to this until the oxygen has been purged. Do not connect it to a vaccum pump to purge it. The oxygen could cause a fire in the pump. Do not connect it to an air compressor to purge it. This may introduce oil and particles that could become a fire or explosion hazard. Leave the valve wide open after it is emptied and over time the oxygen will diffuse with air in a safe manor. Do not do this if you plan to use the tank again for Oxygen service as this will introduce moisture and start corrosion in the tank that would go nuts with the addition of Oxygen again.

[Gun Freak]

Thanks Tech! Lots of useful info there, I appreciate it. I'll take all of that into consideration when I empty it.