NITROX marked tanks MUST be filled to 24% or greater?

[fmerkel]

With the LDS 2 miles away and (previously) fills so reliable I don't even bother to check them I'm hard pressed to deal with a compressor. Seldom actually use NITROX, usually just doing a single tank dive most weekends. NITROX is for multiple tank/multiple dive excursions for us.

 

[sealark]

Medical grade requires a prescription, Welders is the same oxygen the only difference is ABO is vacummed out to remove any possible contaminates. Welder 02 is just topped off and there is a slight chance it could be contaminated with other gasses. Very slight chance and for the difference of a couple dollars i'll us ABO. I would be more worried about that Cancer Stick sticking in your mouth than welders O2. Sorry Just couldn't resist.

 

[manni-yunk]

Medical grade requires a prescription, Welders is the same oxygen the only difference is ABO is vacummed out to remove any possible contaminates. Welder 02 is just topped off and there is a slight chance it could be contaminated with other gasses. Very slight chance and for the difference of a couple dollars i'll us ABO. I would be more worried about that Cancer Stick sticking in your mouth than welders O2. Sorry Just couldn't resist.

Myths and untrue...

Welders grade is vacuumed out and then filled from the SAME exact source. The only difference is serialized tracking......thats it.....

I got that right from (2) different large O2 suppliers. They were honest....they told me point blank that the slight upcharge was for them to have lot/serial numbers on there......but that every tank they fill from the source is treated the same exact way.

Medical Grade...doesnt necessarily require a prescription....but Medical Oxygen treatment does - particularly if you want insurance to cover it. Some suppliers now have "Divers Grade"...which is their medical O2...with a different color tank and tracking mechanism.

 

[sealark]

Good info I will have to check with my suppler if both are vacuumed out and filled I might shift to welders. Things could have changed since I started mixing my own 30 years ago. At first it was hard to get 02 if you told them it was for diving.

 

[tcphil]

Agree with others that there is no DOT regulation that requires the Nitrox sticker. Saying that it has to be 23.5% to trigger nitrox is actually counter to a DOT interpretation letter that states in the first paragraph that it includes 21% to 100%. The 23.5% comes in with the cleaning of aluminum tanks.

http://www.phmsa.dot.gov/staticfiles/PHMSA/Interpretations/2011/110175.pdf

It is interesting to note that this interpretation letter clearly identifies labeling requirements for tanks, including labeling as Div 2.2 (non flammable gas) and 5.1 (oxydizer). For most shops, and definitely individuals, the material of trade exceptions of 49 CFR 173.6 likely kick in (which is why lawn mowing people don't "transport" their gas per all the DOT shipping/labeling stuff).

 

[fmerkel]

Picked up my tanks today. Had a long conversation with the "new" manager of the store, who it turns out is very knowledgeable. He agrees with my position but doesn't KNOW if the 'rules' have been changed by DOT.

The employee that started this somehow forgot to bring in the relevant DOT rules to let me know specifically what the issues are and why. While I was there the store employee had a conversation with the owner of the (3) stores about my concerns. Nothing was settled but a conversation has been started. The compressor at the store is still down.

The organization that is being accused of putting this information out at the 2016 DEMA seminar is not answering my calls or emails.
I will persist.

Got to wonder what the hell is going on. If this was true I think it would be a big deal in the industry. Massive amount of education and changes in policy nationwide would be required, not this little localized disruption.

 

[nadwidny]

Medical grade requires a prescription, Welders is the same oxygen the only difference is ABO is vacummed out to remove any possible contaminates. Welder 02 is just topped off and there is a slight chance it could be contaminated with other gasses. Very slight chance and for the difference of a couple dollars i'll us ABO. I would be more worried about that Cancer Stick sticking in your mouth than welders O2. Sorry Just couldn't resist.

You should since your knowledge is lacking.

Medical grade doesn't always require a prescription. Depends where you are.

You are correct in that all oxygen comes from the same vat however all O2 is vacuumed, even welders. Welders can't afford contaminants any more in their O2 than us that breath it (and perhaps more than). No gas supplier is going to take a chance that a renter back filled their welding O2 tank with acetylene or some other gas before they fill it with O2.

Major difference between welders and ABO is that the spec for ABO is much drier.

If you think my avatar is my real picture you must be new here.

 

[NAM001]

JUST informed by my LDS that it's now a DOT REQUIREMENT that tanks marked with a NITROX band must be filled with a minimum of 24%.

That sounds like BS to me.
If it's true, when did this happen and where exactly can I substantiate that specification?

If someone can post a reference to this i would like to see it. Last i knew any mixd above 23.5 and 50 psi required a O2 cleaning and also a Nitrox Sticker on the tank. Is this somewhat of an extrapulation on this chain of rules?

 

[NAM001]

I sometimes fill my nitrox tanks
with air. Never had a dive shop complain. But it's always the same shop and always the same fill station. I don't think that a tank filled with nitrox can only be filled that way, though it's certainly more profitable for the dive shop to insist upon such a policy.

If it has a nitrox tag on it the tank can only be filled with OCA or hyperfiltered air or safe air what ever you want to call it. 21% is nitrox. Now you cant put trimix in a nitrox marked tank.

 

[NAM001]

I understand that there is a DOT requirement that containers (such as high pressure cylinders) be accurately marked as to contents.

There is a school of thought that filling a cylinder with air when it is marked "nitrox" is in violation of this, because then the cylinder's markings do not accurately reflect its contents. While I do not subscribe to this way of thinking, I can understand it.

air is nitrox