How often do most shops in your area require Nitrox tanks to be O2 cleaned?

[danktex]

I read your post as you stating you learned how to O2 clean by watching someone else. Joanna pointed out that you have the card, I apologized. Not sure what else you'd like on top of that, but that's all I have to offer.

An apology as long as it is sincere is all any one can ask for. I thought that I stated that I had watched tanks being improperly cleaned or not at all. That is why I got the training. Certification is meaningless training, experience and knowledge is every thing.

 

[Joanna.Cordry]

I like Sarah Palin...surprise. You know of the four of them she's the only one with executive level gov't experience.

I'm soooooo signing off now... I shouldn't have even gone there - so totally hijacked this thread - and the truth is... I don't trust any of 'em anymore. Too many years working with politicians and their minions... not many honest or straight-forward ones among the whole lot. Sigh...

I wish this was going to be a diving weekend, but I think it's not... Stay dry, everyone (unless you get a chance to go under water), and I'll be thinking hopeful things for the people (and boats) in Corpus and Houston...

 

[mike_s]

UV light testing. Anyone who can do a decent VIP on a tank should be able to see most indications that would point toward a required O2 cleaning. After that, use a UV light to look for other contaminants that fluoresce. If nothing shows then the tank is clean enough for O2 use.

huh?

Kvalve, can you give a reference to what this is based on?

I mean I've never seen anything or anyone say that just because you can't see something with a UV light that a tank is clean enough for O2 use?

K Valve.

You still haven't answered the above question about how not seeing something with a UV light can guarentee it being o2 clean?

 

[k-valve]

I hear ya, brother. We have a charter going out Wednesday night at 7:00 if you are available and want to dive the trees. But no tanks on the boat that aren't perfectly cleaned and ........ Ok, I won't provoke you......

What? You're not going to poke the rabid dog with a stick? LOL!

I'll check into going out with you Wed. Gotta confirm my schedule with Angie...the keeper of all schedules where I live.

 

[k-valve]

An apology as long as it is sincere is all any one can ask for. I thought that I stated that I had watched tanks being improperly cleaned or not at all. That is why I got the training. Certification is meaningless training, experience and knowledge is every thing.

Glad we can agree on something before signing off for the evening.

 

[Lake Travis Scuba]

I like a good ol' fashioned argument and glad to be on the sidelines this time. Let me know what the Keeper of Schedules says about your Wednesday night. There is a bridge calling for a visit...just gotta get the guy in the know on the boat to show me where to drop you....

 

[texdiveguy]

Robert......

Times and cost for Wed. evening??

 

[danktex]

Glad we can agree on something before signing off for the evening.

Well said. Good night all.

 

[Lake Travis Scuba]

Dive Cost: $25 (we usually do two tanks)
Time: 7:00 pm at Riviera Marina
Diving with Friends: Priceless

 

[k-valve]

K Valve.

You still haven't answered the above question about how not seeing something with a UV light can guarantee it being o2 clean?

Honestly? I don't feel like looking all over the Internet to gather a fact here and there and piecing it all together for ya'll. You know you won't find it in any O2 Service Manual. We won't find it in guidelines developed by PADI or SSI. They make policies that support their affiliates. I don't blame them for that. It's a smart business plan. They want to O2 clean our tanks as often as they can.

Here are the points I tried to make:

1. I stated earlier in this convoluted mess that it doesn't matter how well you O2 clean a tank, it's going to be contaminated with the first fill that has any air in it, Grade E or otherwise. That said, you don't have to have a perfectly clean tank to do a safe O2 fill. It doesn't matter if there is a very small amount of contaminant.

2. The fact is that tanks don't have to be perfectly clean. I'm not saying that some yahoo can walk in with an old tank and that we should VIP it and call it good for oxygen use. The OP stated that his tanks were cleaned less than a year earlier. If they were cleaned properly and there hasn't been a catastrophic failure with the valve or neck o-ring, the tank hasn't been breathed down to near zero psi, or low grade air introduced then it's going to be clean enough for O2 service.

3. If a tank has been recently O2 cleaned we will be able to see any relevant contaminants with a good, quality VIP and a UV light. What is likely to get into a tank that is well-maintained? Nothing but gas. Now if someone is stupid and let's the gas out to lube the neck o-ring with motor oil we'll be able to see that.

4. I don't know you, but if you fill tanks with oxygen you know that you fill them slowly to avoid heating. Heating usually occurs by friction where the gas has to go around or through something too quickly. Like through the tank valve or tubing leading through the fill station. The build up of contaminants in valves is what is concerning because that's where most friction occurs. I didn't say don't clean your valves. I'm just talking about the tank and tanks don't have a bunch of tight turns that cause friction. The gas is usually heating before it's even introduced to the tank then continues to heat depending on how fast you fill it and how much pressure you apply. Anyone who fills a tank with a gas no more stable than pure oxygen should be looking out for this.

5. Once the gas enters the valve on the way out through the dip tube that's a whole new ballgame. But the tank? No. A minute bit of contaminant in a tank that you can't see with with a quality VIP (emphasis on the word quality) and UV scan isn't going to cause the dive shop to burst into flames. Not gonna happen.

Now that I've said all of that I still think even the best maintained tank needs to be O2 cleaned on some kind of schedule. I just don't think it is necessary for all tanks to have an annual O2 cleaning, and I don't think you have to tumble them if there isn't a good reason to do it.

Now if ya'll want to go find a bunch of research to dispute that knock yourselves out. I'm not going to go find any to contradict what is found. Research is a funny thing...there is something out there to dispute about anything you want to argue about. It's all up to the researcher and if and how much they are biased. I'm not interested in a debate. I've given my 2 cents. Take it for what you will. Do with it what you'd like. I'll continue to do what works for me...you all can continue to do what works for you.