Nitrox Tank Marking

[Bubbles McGee]

I have seen posts like this over the years on ScubaBoard, posts that suggest that the writer believes no one actually analyzes their tanks. I keep wondering where these people are diving. I don't believe I have ever experienced a situation where I have rented nitrox tanks and not been expected to analyze the blend on the premises, and I have gotten nitrox in a lot of places over a lot of years.

Thanks @boulderjohn . That's what is outlined in the PADI course. I've completed the online training and will be finishing up soon. It would make zero sense to me not to analyze tanks and confirm blends. I would not take that risk. Apologies if my post suggested a less than serious view on the subject.

 

[scubadiver888]

read your heart out.
The first big filter was likely the water filter that takes most all of the nasty's out and is literally just a big open tube. The last one contains the actual filter cartridge where things like CO are converted to CO2 if equipped, and everything else is taken out. Sometimes there will be a second filter stack, but again that is usually reserved for BIG air compressors to keep the size of the filter stacks reasonable.
Filter System Design

Thanks. I like the website. Something to read during layovers at airports.

Ding, ding, ding. First big filter had water coming out of it. I'd love to just rip one of those apart.

 

[TrimixToo]

Thanks. I like the website. Something to read during layovers at airports.

Ding, ding, ding. First big filter had water coming out of it. I'd love to just rip one of those apart.

This is wandering a bit far afield of tank markings, but there are no drains on (at least my) filter housings. Any water in the filters is trapped by the molecular sieve (typically 13X), a dessicant. There is, however, a housing that *looks* like a filter housing and is not a filter housing after the final stage and ahead of the first filter. It's the coalescer. It does have a drain, and water definitely does come out of the coalescer.

 

[Brian Gronberg]

Thanks @boulderjohn . That's what is outlined in the PADI course. I've completed the online training and will be finishing up soon. It would make zero sense to me not to analyze tanks and confirm blends. I would not take that risk. Apologies if my post suggested a less than serious view on the subject.

Great points and process to keep track of your tanks. I guess being freshly certified, book marking instruction differs greatly from real world practice in terms of marking. I wouldn't accept a tank that I've not personally analyzed and purchased my own tanks to know exactly how they have been used, checked, stored, etc.

Thanks again for the input!

 

[Brian Gronberg]

Seems to me a green on/off knob would solve this world problem?

Great idea!

 

[tbone1004]

Great points and process to keep track of your tanks. I guess being freshly certified, book marking instruction differs greatly from real world practice in terms of marking. I wouldn't accept a tank that I've not personally analyzed and purchased my own tanks to know exactly how they have been used, checked, stored, etc.

Thanks again for the input!

if that all makes you nervous, I wouldn't recommend driving up to cave country, we'd probably terrify you lol

 

[Brian Gronberg]

Brian-
In the larger world of commercial gasses and gas bottles?
No one has to worry about salt water but no one uses plastic sleeves either. Your tanks are going to be used for EAN "forever" more or less?
So, you do what commercial gas people do. PAINT the appropriate color code on the tank. The obsolete UK marking would have been black and white "quarters" on the head of the tank. Very distinctive. The modern US standard would be a three inch wide yellow band, with an inch wide green band in the center of it. (Easiest to paint a wide yellow band, then green over the center of it.)
Pretty much says the same thing as "NITROX" without having any plastic or stickers to worry about.
And if you want to add anything like "EAN 32 only" just use a thick black Sharpie.

A little imagine, a glance at commercial standards, you can figure it out.

And it should also make it very unlikely that someone else will confuse your tanks with theirs.

Yes, my new tanks will always have EAN in them. I think I'll go the sharpie route since others have brought up visuals requiring the labels be removed and paint would be similar.

Thanks for the input I really appreciate it.

Brian

 

[Brian Gronberg]

if that all makes you nervous, I wouldn't recommend driving up to cave country, we'd probably terrify you lol

I didn't indicate that anything made me nervous. I'm sure you carry more than one flashlight, correct? Not because you are nervous about the first one failing, it's about planning ahead

 

[Glen Stone]

I thought the same. Does everyone reanalyze to confirm the blend percentage on rentals?

Well, if you are filling at a reputable fill station and are getting air or basic 32 or 36 nitrox and if there is a tape on the tank telling the fill analysis, date, fillers initials, etc, like it's supposed to then no, it's probably not necessary to re-analyze. At some point you have to trust the dive shop. But if you have the ability to test, then why not? I re-analyze everything. Also did you realize that the word "analyze" comes from the word "anal eyes"!

 

[boulderjohn]

Well, if you are filling at a reputable fill station and are getting air or basic 32 or 36 nitrox and if there is a tape on the tank telling the fill analysis, date, fillers initials, etc, like it's supposed to then no, it's probably not necessary to re-analyze. At some point you have to trust the dive shop. But if you have the ability to test, then why not? I re-analyze everything. Also did you realize that the word "analyze" comes from the word "anal eyes"!

I am not sure I understand this post, so if I misunderstood, please forgive me.

You should always analyze your own tanks. Don't accept the analysis of someone else who did it out of your sight. The writing on that tape should pretty much always be yours. (The exceptions are close enough, as in a dive team working together on it.)

But do you have to re-analyze? It depends.

In South Florida, when I analyze tanks at the fill station, I take them directly to the boat. I get on the boat and set up my gear. We get to the dive site. It would take a major miracle to change the blend, so, no, there is no new analysis.

In Colorado, I mix most of my gas at home. I analyze and mark the tanks. Sometime later, sometimes several days, I drive to New Mexico and use them. At that point, I lose all trust in my memory. I get out my analyzer and do it all over again. I simply don't want to make a mistake, and that extra time is worth it.