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

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fmerkel

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There are rules. PSI makes them.
According to Mark, they don't make them, they try to educate about them. I was quite clear asking if this was an interpretation of a rule. He insisted not, it was the rule. I have not known Mark to be anything but a stand up guy. I'm taking his word on this for the time being.

The rules are so damn hard to find relevant parts, so complex, written so badly, and frustrating that I've given up trying to find the actual part for now. :confused:
 

BRT

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According to Mark, they don't make them, they try to educate about them. I was quite clear asking if this was an interpretation of a rule. He insisted not, it was the rule. I have not known Mark to be anything but a stand up guy. I'm taking his word on this for the time being.

The rules are so damn hard to find relevant parts, so complex, written so badly, and frustrating that I've given up trying to find the actual part for now. :confused:

I've spent a bunch of time tracing their "rules" back through. When you get to the end the connections are pretty tenuous.
 

sunnyboy

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Other than DOT and the CDN equivalent standards regarding tank hydros, there are no "rules".

There is no "scuba rules committee" to come up with rules about EAN or tank marking or even visual inspections. A lot of the "rules" come from liability concerns by shops and boats.

There are common practices, and even guidelines and recommendations, but no hard and fast rules, other than the one rule: "the shop makes the rules for that shop". So if you want air or EAN fills from a shop, you live by their rules or find another shop.
 
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NAM001

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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. :stirpot: 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.

The course is a very informative class. Keep in mind that the class takes a one solution for all approach. I and others find it hard to totally agree with some of the positions of PSI , however the open the class with,,, follow these proceedures and you will have the best chance of not being found at fault in a litigation. That is their root goal. Many of the rules are so intrusive that you can not function with them. for instance they originally tried to make O2 cleaning for anything above20% O2 content, That went down the toilet when they had to accept that every tire filling station now had to be O2 cleaned tp put air in your tires, then they raised ti to 21 and found a couple of places in the US that ambient air was above 21%. they eventually settled on 23.5 & > 50psi. So much of the rules do not have a lot of science backing it. Many of the policies are centered around if you cant look at it and know without a doubt then mandate a label. Air and NITROX are not the same..... By their standards any one that home fills is breaking the law. So much of what is being said take it nod your head and get your cert. The inspection procedures and documentation will amaze you when you see what is required. You will probably never trust a shop to do one right again. Another thing is that they speak from the aspect that you are a business and are tied to business related federal codes. Also pay attention to your limits in making Nitrox as far as PP and continuous blending goes. In the end you find that the 90% can not afford to comply. Which by the way making nitrox is another 2-3 year course for another couple of hundred bucks. For what it is worth as tank marking goes, I totally believe in marking a tank used with other than nitrox based air with normal O2 content and above. IE trimix tanks deco tanks. PSI has a belief that a 32% tank should never have anything but 32% in it and the tank should be permanately marked as such so it is never confused to have any other contents. All a nitrox tank band says is it is normal atmosphere based gas O2 N2 at some mixture. We have grown to accept that the band means nothing less than OCA is to go in it. BUT with them containing only OCA is not allowed unless you raise the O2 content.
 
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fmerkel

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PSI is not a law making body. Not in the US, not in Canada, not anywhere.
Something I learned by being on the jury on a wrongful death of a 9 year old boy is that the law is one thing, lawyers and juries are entirely another. I guess that's why the law is so gawd-awful complicated and people tend to dislike lawyers. Their job is to twist, color, subvert, occlude, manipulate and manage the law to sway the jury to their clients favor. The law is written to cover all the a$$holes trying to do anything they can to get around 'common sense', which apparently ain't so common.

I totally get, that if you are in the position of PSI, they end up making judgements based on the written rules, about how legal cases may be ruled upon when things go terribly wrong. They also probably end up being expert witnesses. I don't envy anyone that has to come near any kind of case like that. There are no winners, just some people that lose less badly than the other side.

Being a consumer, is not being an owner, is not being a shop employee. With something like this all end up having different perspectives.
 

WarrenZ

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For what it's worth as long as the shop is pumping OCA then they can fill your nitrox tank with their air and your not going to have any problems with nitrox later but if their regular air is just grade d or e then I wouldn't trust the tank for pp blending later.
 
R

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My impression is the princilpe federal rule makers in th USA that may affect scuba tanks are DOT, OSHA, and USN. As private individuals, one might argue that none of those hav authority over us. And it is not clear to me how any of them have authority over dive shops and ops. But, more often than not those businesses will opt to voluntarily follow those rule that are to their advantage (usually from a profit standpoint). I usually just avoid doing business with those that do not meet my needs.
 

KevinNM

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Scuba is a tiny, tiny portion of the compressed gas industry. So, in general, the rules are not written for scuba shops, they are written to support welding shops, hospitals, home oxygen suppliers, coke and pepsi distributors and other vastly larger industries. But the Feds can get very annoyed if you ignore their rules and it comes to their attention.
 
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