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

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To answer your original question nowhere in OZ have I seen anyone be upset by tanks with NX stickers and having air pumped into them. If I did find someone I would simply put duck tape on them and then write Nx 21% MOD 57m and see what they say.
 
you cant get around it if you are PP blending. You are going to excede 40% when you PP.
Yup.

Here in town there are at least three sources for mixed gas: At least two diving clubs and one of the LDSs. Not sure about the other LDS. My club has a continuous mixer which limits the FO2 to 40%. No O2 cleaning required, no nitrox tank band required. The other club and the LDS do PP blending and require O2 cleaned tanks and valves. Since we all have good quality air which doesn't screw up O2 cleaning, I haven't heard of anyone refusing to fill air in a tank with a nitrox tank band.

How the LDS handles blending in tanks with a valid O2 clean sticker, but which they have no info about the quality of the gas that has previously gone into it, I have no idea.
 
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?
It seems like someone might have been making a logical error. For example: IF A then B does not guarantee that IF B then A.
Yes IF you you will fill a tank with greater than 23.5 % Then you must have an Evidence of Inspection Sticker - Nitrox Service ... is true. However, it is a logical fallacy to state that IF I have a Nitrox Service Vis sticker on a cylinder, then you will fill a tank with greater than 23.5 %.

And - a nitrox service VIS Sticker does not require you to put a Nitrox WRAP (6 inch tall sticker) which is what the OP mentioned in his original post.
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.
I do it all day long (Trimix or OCA) in my Nitrox inspected personal tanks. The have a small Evidence of Inspection Sticker - Nitrox Service Oxygen cleaned VIS sticker - and a piece of duct tape with the mix contents. When the mix changes from OCA, to Nitrox, to Trimix - the duct tape changes - and that's it. And that's what tec. divers generally do. Although you can buy a Nitrox, or Trimix (or Voodoo Gas Wrap) - I would scrape it off at ever annual visual inspection - along with the old Evidence of Inspection Sticker - Nitrox Service. These wraps on my personal tanks are pointless.

Now on our shop tanks - we do have rental cylinders with the Nitrox Wrap - and it is useful to distinguish between cylinders that only contain air (OCA) versus cylinders that may have a mix other than Air (22% - 40%). These tanks circulate through a much greater set of hands - and that wrap is a useful visual indicator.
 
That is exactly what i have always understood. If you ingest you vac. If you burn you dont.

I can only speak for the 2 major gas suppliers in my areas.....one in which is HUGE everywhere.

Without any doubt, whatsoever, I can say that they vacuum ever single welding tank...every time. In fact, every few years when I bring this up, they laugh and say "here we go again with the scuba guys online".

They only difference in how certain grades are tracked and traced, but they are all vacuumed.
 
I can only speak for the 2 major gas suppliers in my areas.....one in which is HUGE everywhere.

Without any doubt, whatsoever, I can say that they vacuum ever single welding tank...every time. In fact, every few years when I bring this up, they laugh and say "here we go again with the scuba guys online".

They only difference in how certain grades are tracked and traced, but they are all vacuumed.
This is only an unsubstantiated rumor... (Let's spread it everywhere and we can call it true.)

I heard for industrial O2 - the tanks were brought to a vacuum once. For medical / ABO / Diver grade - they were cycled or brought to a vacuum several times for a higher degree of purity.

Just what I heard - take it with a grain of salt.
 
Good grief! All this noise just confirms my opinion that all new divers should be trained for EAN/Nitrox right out of the gate and be prepared to analyze every tank of gas they dive with. It just seems irresponsible to dive any rented or borrowed tank without confirming the contents.
 
Good grief! All this noise just confirms my opinion that all new divers should be trained for EAN/Nitrox right out of the gate and be prepared to analyze every tank of gas they dive with. It just seems irresponsible to dive any rented or borrowed tank without confirming the contents.
Yeah - you really take your life into your hands when you don't...

By reputation, I know of an incompetent FSO who didn't exactly know how to work the panel. They accidentally filled a rental cylinder inspected for air service (Not even a Nitrox VIS. Not Oxygen clean.) with 70% Oxygen. It was caught after the tank went out of the shop for rental - but before the cylinder went in the water. An Air cylinder filled with 70%...

Scary stuff. Analyze your gas.
 
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I almost always use nitrox. My tanks are all O2 cleaned and carry a VIS sticker to that effect. I do not have any nitox banding on my tanks.

I have never had the lack of banding remarked upon, locally or while traveling with them, banked or partial pressure filled. Contents get clearly marked with duct tape on the neck. That is sufficient.

Too much FUD being spread.
 
air is nitrox

I used that argument......didn't work. :banghead:

I got a response back from PSI-PCI. I don't know why but they didn't understand the question. I asked exactly the same thing I did here and you all seem to have understood it.

Their initial response: [Not exactly clear the question. Were you trying to get an air fill in a tank marked for Nitrox? We do teach that a cylinder used in O2 or enriched air at 23.5% O2 be cleaned to specific O2 standards. This is due to most fill stations not having pre-blended gas and because with partial pressure blending, pure O2 is the first gas into the cylinder.]

I've rephrased the question to make it quite clear, I hope, and sent it back. We'll see. :popcorn:
 
There is a difference between misunderstanding a question and avoiding answering a question.
 
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