Tanks suitable for O2

[Packhorse]

Hi guys.

Just after some infomation as to what the regulations are around the world for putting EAN40 -EAN99 and 100% O2 into scuba cylinders.

In New Zealand we have a bit of a problem.
No tanks are certified for EAN mixes above 40% and only a select few are certified for 100% O2 and these tend to be steel rebreather tanks.
For some reason the powers that be think EAN40+ is dangerous. (Obviously the people who made the rules dont know jack about diving).

Now im not really interested in the O2 clean side of things, more the types of cylinders that can hold O2 and high EAN mixes and also what pressure the tanks can be filled to.

 

[JeffG]

Now im not really interested in the O2 clean side of things, more the types of cylinders that can hold O2 and high EAN mixes and also what pressure the tanks can be filled to.

All and to their rated pressure.

 

[Jimmer]

I agree with Jeff, I've never heard of a tank being deemed unsuitable. My LDS took one of their DAN O2 kits with an aluminum tank to Praxair to be filled, and was told that aluminum can't handle O2. So my instructor gave them DAN's phone number, and a few minutes later the tank was being filled with O2.

 

[Packhorse]

OK thanks guys. So this is the situation in Canada correct?

 

[Jimmer]

Canada and the USA as far as I know. I've talked to many people on this board that use both aluminum and steel for O2 tanks.

 

[Dirkadiver]

Yep, 02 in any cylinder here in the states too. It's not the tank itself that is a problem w/ high 02 fills, its the cleanliness of the tank that is the issue. The tanks just need to be tumbled/02 cleaned & your good to go. Need to make sure you have your reg 02 cleaned as well.

 

[DA Aquamaster]

My LDS took one of their DAN O2 kits with an aluminum tank to Praxair to be filled, and was told that aluminum can't handle O2.

Apparently the Praxair tank monkey on duty had never encountered one of the gazillion or so aluminum medical O2 cylinders in service. I suspect there are currently more AL medical O2 cylinders in service than steel.

 

[Jimmer]

Apparently the Praxair tank monkey on duty had never encountered one of the gazillion or so aluminum medical O2 cylinders in service. I suspect there are currently more AL medical O2 cylinders in service than steel.

I agree with you, goes to show that the Scuba industry isn't the only one with clueless tank monkeys.

 

[Azza]

Here the issue seems to be with some "person" at ERMA (government agency...not sure what they do except make red tape) who thinks that the pressure and O2 content are the issues.

 

[oxyhacker]

All kinds of tanks get used for deco 100% here, but probably more Luxfer 30s and 40s than anything else. And probably more alu 80s for high-FO2 travel and deco mixes. So I wouldn't worry about using aluminum, though at one time one of the major US gas suppliers had a thing about it being unsuitable.

If there is a troublespot, its the valve and not the tank. All scuba valves are a bit iffy for 02 service, some more so than others.