Ultra Pure Air - O2 Cleaned Tanks

[MDColson]

Am I correct in assuming that if a shop makes their NITROX by using partial pressure blending, then the air they use is 'ultra pure'? I was told that I can put 'ultra pure' air into my O2 cleaned tanks. So if I go to another shop and they use partial pressure filling, can I let them put AIR into my O2 cleaned tanks?

MDColson

 

[Ontario Diver]

Am I correct in assuming that if a shop makes their NITROX by using partial pressure blending, then the air they use is 'ultra pure'? I was told that I can put 'ultra pure' air into my O2 cleaned tanks. So if I go to another shop and they use partial pressure filling, can I let them put AIR into my O2 cleaned tanks?

MDColson

This question is often asked.

When your tanks are O2 cleaned, two things are done. As many hydrocarbons as possilble are removed from the tank so there is nothing to burn and all materials in and around the tank and valve are replace with materials that can handle a high O2 atmosphere without burning.

Air that is used to mix NITROX **should** have been purified before being added to the O2 to make the Nitros gas mix. This is usually know as Hyper pure air and needs to meet some very strict standards.

You can always put HyperPure air into your O2 Cleaned tanks with no issues because the vast majority of the hydrocarbons have been removed from it.

If you put non-filtered air into your 02 tanks, you may be introducing hydrocarbons and "dirtying" your tanks.

You can assume that a shop uses hyper pure air when they mix thier nitrox, but I suggest you ask to see thier testing certificates. By the token, you may go to another shop and assume that since they do PP blending, all of thier air is hyper pure, but I would ask to see thier testing cert as well.

 

[murphdivers286]

Take a look at this post!!!!



Maybe this will help you to understand filling plain filtered air in your nitrox tanks.

When you fill 32% nitrox you have 32% O2. When you want plain air look at it as 21% nitrox.

It helped me. Maybe it will help you.

 

[MDColson]

Thanks for your help Ontario Diver. I just wanted to make sure I would be OK putting air into my recently O2 cleaned tanks. For instance tomorrow I'm doing a 1 tank dive in about 15-18 feet of water. There's no reason for me to pay twice as much for nitrox, I'd be content with just plain old air... So should I just ask the shop tomorrow (not my usual LDS) if their air is ultra/hyper pure, and if so tell them to just put air in it?


Murph-

I hope everything works out with those tanks! Like I said when I was down there, I would require (not ask) that the shop at the spring pay for it. Hopefully you have already brought it to their attention, as it has been a few weeks now... $50 seems steep for an O2 cleaning. I just got a tank yesterday and it was only $15 to get it cleaned if I did it right then when I purchased the tank (usually only $35). I know the two of you have some affiliation with that shop, but that's no way to take care of a loyal customer!!!

MDColson

 

[Ontario Diver]

So should I just ask the shop tomorrow (not my usual LDS) if their air is ultra/hyper pure, and if so tell them to just put air in it?
MDColson

Yeah, if you want you can always ask how/when they get thier air tested. You can even ask to see the certificate. Or you can just trust them.... Caveat Emptor.

PADI places are expected to test thier air quarterly ( If I Remeber Correctly) - but no one ever checks.

 

[padiscubapro]

Thanks for your help Ontario Diver. I just wanted to make sure I would be OK putting air into my recently O2 cleaned tanks. For instance tomorrow I'm doing a 1 tank dive in about 15-18 feet of water. There's no reason for me to pay twice as much for nitrox, I'd be content with just plain old air... So should I just ask the shop tomorrow (not my usual LDS) if their air is ultra/hyper pure, and if so tell them to just put air in it?


Murph-

I hope everything works out with those tanks! Like I said when I was down there, I would require (not ask) that the shop at the spring pay for it. Hopefully you have already brought it to their attention, as it has been a few weeks now... $50 seems steep for an O2 cleaning. I just got a tank yesterday and it was only $15 to get it cleaned if I did it right then when I purchased the tank (usually only $35). I know the two of you have some affiliation with that shop, but that's no way to take care of a loyal customer!!!

MDColson

Mdcolson,
Padi on Paper requires air testing but no one ever follows up or asks for proof. In my experience most stores do not test theri gas unless required (like in florida).
The only agency that REQUIRES proof of gas testing is ANDI. each facility must forward their quarterly gas analysis reports (BTW ANDI has the toughest limits of any agency), if the fail to provide proof they will be contacted and if not corrected will noose their license.
Murphy,
$20-$30 for oxygen cleaning of a scuba cylinder is acceptable. If its a luxfer cylinder, as of jan 2000 they come oxygen clean from the factory, faber cylinders also come oxygen clean (oms cylinders are also faber cylinders).
Neither catalina or PST state whether they are clean or not so they should be cleaned. Judging by the statement on catalinas site they probably aren't o2 clean, but unless thethe tech is an ANDI certified service tech they are doing a cleaning they arent certified to do by the manufacturer. Currently no other agency program parallels ANDI Oxygen standards..
The valves may have to be cleaned for service but that would be a seperate fee since thats would entitle rebuilding the valve.

 

[padiscubapro]

Thanks for your help Ontario Diver. I just wanted to make sure I would be OK putting air into my recently O2 cleaned tanks. For instance tomorrow I'm doing a 1 tank dive in about 15-18 feet of water. There's no reason for me to pay twice as much for nitrox, I'd be content with just plain old air... So should I just ask the shop tomorrow (not my usual LDS) if their air is ultra/hyper pure, and if so tell them to just put air in it?

Why not get the shop to put in 36%-40% (or 50% if you were ANDI certified or equivalent). You will feel much better in the end..
Money should never be a concern when it comes to diving.. ALways choose the best tools you have available

 

[Lemonade]

Neither catalina or PST state whether they are clean or not so they should be cleaned.

I do not have any materials to back me up, but when I was buying my new PSTs in early 2003, I saw a brochure or a catalogue where it was stated they come O2-clean from the factory.

 

[MDColson]

Padiscubapro-

I agree... When I dive I almost always dive nitrox. However if I'm in the pool or in the 'new england beach shallows ~15ft' air will suffice, and I just wanted to make sure I had that option...

MDColson

 

[Ray2]

Wow,it's been a long time since I posted on this board,all the changes are great!!My hats off to you guy's.The question I have is,what do you oxygen clean a cylinder with?I know one shop that does it with Simple Green,but its only one shop.I asked our pumping station operator,as I have been in the business of selling industrial,medical and specialty gasses for longer than I care to say.He thought I was crazy to put anything in a cylinder accept water ie: hydrostatic test,apparentlley once an HP cylinders service has been changed from Oxy to another gas it cannot go back,at least in our business it can't.The Simple Green treatment seems to be a closely guarded secret or is it?Anyway just a thought,can anybody help?