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

[NAM001]

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.

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.

Yes and once again this is a matter that is widely applied in so many different interpretations. Many of us older guys grew up on the set of rules that made sense. Now we have the protectionists that have to save us from our selves and make one size fits all policies and it does not work. It does however tend to make the end user less responsible for what they do. On the flip side,,,,, things change, we do not have the sudo technical people taking diving classes and now have people that cant make change for a dollar diving. For home fillers it is all pretty much moot. but for business filling i do believe in markings on tanks. Im all for bands denoting the contents catagory for all other than 20-40% nitrox. I would not casually mix or even trust any tank that came from a shop that did <20% blends or trimix. Most of us use shops that dont do trimix or <20% blends. I also would not mix a tank of 32% in a tank saying oxygen 20 or 70 on it. or put 100% O2 in a tank with meerly a nitrox band on it. Some things have to be specially marked in a manor that draws attention to even the most trusting of users. You need to show the purpose of the tank.

Tank bands ... there is someting that says if used for nitrox a band sticker must be applied. Now i know there is a difference in commerce transportation and personal use. People forem one side seem to argue the other side of this type of requirement. After all there is no global law or regulation requiring a tank to be with in hydro in order to fill it.

 

[NAM001]

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.

I am slowly coming to believe the same thing.

 

[NAM001]

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

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.

YES and that is the same reply i have always got on this subject. Notice they used the word SPECIFIC when talking about O2 standards. Yet they say must be cleaned to the same standard as to use for O2 service because of posible PP blending. PSI like I have said before is nore a legal standard service fwhos success is achieved in 2 arenas. If you are sued you hav ethe documented paperwork to show you comlied with regulatory practices and 2 no accidents no suit.

If psi dealt with driving they would reserarch all agencies as to how fasts o can go on a road and they teach the lowest speed is the standard, You comply with that and you comply with all.

 

[Scared Silly]

For the OP here is the correct sticker you want for your cylinders:

You can buy them here: Tank stickers

 

[Peter69_56]

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

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.

Simpler question might be I want a 21% Nx fill..................................

 

[redacted]

Simpler question might be I want a 21% Nx fill..................................

Air is $8. Nitrox is $15. Your bill is ....

 

[Peter69_56]

Air is $8. Nitrox is $15. Your bill is ....

Damn screwed over again

 

[sealark]

Put a sticker or something to mark a different than 20.94 regular air mix so you don't mistakenly pick up a 35% mix for a 200 ft dive. Get your own compressor and mix your own gas. I am on mix 267 for this year. Been mixing dive gasses since 1966. One o2 incident after changing a Gauge in my home system. Gauge must have had small amount of oil in it. was filling a bottle from O2 to 450 PSI. BOOM.

 

[oldschoolto]

Or get medical or welding grade and save even more.

I guess it all depends on the shop... I put in a deep pool to do Hyperbaric treatments... I asked my gas guy to drop off a "T" of medical O2... He said, Why.... O2 is O2... All comes out of the same whip.... So, welding O2 it is...

Jim...

 

[fmerkel]

I got an email from Mark Gresham of PSI-PCI. to call him, which I immediately did. I gather this thread has caused some extra phone traffic for them to deal with. He's been on the road with his whole crew for DEMA and other classes. It would appear that some phone calls and emails went astray or unanswered because of this, which he was not happy about. We had a very nice discussion at some length. He certainly would have like to have had our conversation at the beginning, instead of the way it rolled out. I agree, though I've learned a lot going down this path also.

I got a mini-education from Mark on NITROX tanks, history, filling, labeling, fill stations, O2 compatible air, the widespread lack of compliance in the dive industry regarding adhering to the rules (yes, there apparently are rules), and a fair number of related associated topics. Mark is an encyclopedia of information on this subject and has an enthusiastic willingness to share it. I have met Mark a couple times before when he came to our Club. He has always come across this way, which is why I attempted to call PSI before I finally took this to SB out of some frustration and wanting specific information if I could get it.

What's this all mean, for me at this point after the conversation?
Going forward, at least for now, my NITROX tanks are going to be reserved for NITROX. I'll be making a few more trips to the shop instead of getting a larger mess of them filled with air all at once. I'll probably be doing a few of my more aggressive dives with NITROX, which may be a good idea. Historically I don't have trouble with the dives, but maybe the drive home will be not quite so tiring....we'll see. If so, that would be a good thing.

I'll be asking some more penetrating questions specifically about the grade of air being delivered by my LDS. Grade E, O2 compatible air, is preferred and (theoretically) required for a NITROX tank. I suspect this is often not the case. I'll want to know how they fill a NITROX tank. If they fill with Grade D, and do partial pressure blending (100% O2, then diluted with air to the appropriate %), the whole purpose of a NITROX clean tank is defeated.The labeling is theoretically designed to keep a clean tank clean, or at least that's how I understand it at this point. There was a lot to absorb.
I'll be asking about how their compressor is maintained, and if the air is tested on a regular basis. 20 years of diving and I've never done this.
I know the owner of my LDS is evaluating how to deal with this new information, and how it impacts his business. I suspect consumer education and the rationale for his decision will be somewhat thorny to deal with. I certainly was.
I'll be taking the PSI-PCI course to get deeper into this regulatory confusion. I dislike it when I don't understand stuff. With my stable of tanks it may be a valuable education.

To me it's clear that the consumer/diver is not at any appreciable risk of fire and/or explosion of tanks, shop employees are. At least some of these rules are for their safety during filling. Ultimately they are for everyone's safety, if everyone is on the same page and using the same standards. That's what standards are supposed to be about. Right now, it's kind of a mess with not much compliance and a host of interpretations. No wonder there is confusion.