Tank Identification Help

[macado]

So the jury is still is out on that tank. I had a room full of PSI instructors and it still could go either way. Luis also looked at it and I think he said it's also questionable. Not sure if he want's to comment?

The pitting covers a large area on the bottom of the tank but it seems very difficult to determine the depth.

Someone suggested I have the tank sandblasted to see if it would make it easier to determine the extend of the damage. Because I was given these tanks for free, I'm thinking of maybe investing a little more money into this project.

One thing I gathered from my VCI class was that it seems very hard to make this type of determination. If the damage or pitting is bad/significant then there seem to be no questions whether to condemn the cylinder however it seems in a situation like this, it's very hard to make the determination and falls back to best judgment and guessing.

This is what scares me the most. I could conceivably bring this into another shop and gamble my chance of them slapping a sticker on it or even just do the inspection myself. Both would be stupid in my opinion, I guess I'm just being stubborn since I would really like to save this tank.

[macado]

"The dive shop does hydros in-house but at a separate facility."

What does that mean, the shops owns both but one doesn't trust the other to do a proper visual. this sounds screwy. I would ask where this "other" facility is and pay it a visit to determine the connection between the two. Crap like this never fails to amaze me.

I don't want to bad mouth the dive shop because I personally don't know their hydro process. I will say that the dive shop in question has been around for a long time and is very supportive of vintage diving and respectful of vintage gear. They're not afraid of filling older tanks or dealing with 1/2" tapered cylinders.

They have their own hydro facility but it is done in a separate building. They also hydro more than just scuba cylinders.

After looking at the tank in question myself more thoroughly and speaking with some PSI instructors I can understand their hesitation to pass the tank for a visual.

[captain]

I have to ask again why on earth would a hydro shop put their stamp on the tank essentially certifying that it's good to go then fail it on a vip. Makes no sense, if it failed it failed, it get no stamp other than the the DOT 3AA and the service pressure being X-ed out. The insanity goes on. Thank Bill High he formed a company then created a need for it. It usually works the other way, the need comes first then the company.

[Bryan]

I have to ask again why on earth would a hydro shop put their stamp on the tank essentially certifying that it's good to go then fail it on a vip. Makes no sense, if it failed it failed, it get no stamp other than the the DOT 3AA and the service pressure being X-ed out. The insanity goes on. Thank Bill High he formed a company then created a need for it. It usually works the other way, the need comes first then the company.

[luis]

In DOT CFR 49, you will find that the definition for “fail” and “condemned” are very different.

A tank (like in this case) can fail, but if it can be cleaned to the point that a satisfactory inspection can be made, it is then possible to pass it. Condemned is final. At this point this tank has some scaling that needs cleaning before a good observation can take place.

It is very common to fail a tank, but not condemn it.

I totally agree that the cylinder should not have been stamped just yet, but to me, that points to a mistake from an employee. The cylinder should not have been stamped until it passed a visual in accordance with CGA C-6. Perhaps the employee needs more training, not less.

I am not sure if the employees in this dive shop are PSI-PCI certified. They may be, but it is just as likely they are not.

I know the dive shop he used. I can't speak for any particular employee in the shop, but the shop is probably one of the best shops I have ever dealt with. The owner is very knowledgeable and has been in business for a long time.

[captain]

According to the OP a room full of PSI inspectors looked at it. All apparently received the same training and used the same techniques to inspect the tank. Inspector Larry says it passes, inspector Curly says it fails and inspector Mo can't decide if it fails or passes. Yuck,yuck,yuck.

I guess we need inspection by consensus, let 10 inspectors look at a tank and vote pass or fail. What will be the passing grade, 6 of 10, 8 of 10 or 10 of 10. What happens if the vote is 5 5, call in another inspector as a tie breaker. Seems tank inspectors opinions are like AH's, everybody's got one.

Just because someone owns tools doesn't make them a mechanic.

[swimjim]

"Just because someone owns tools doesn't make them a mechanic."

You got that right!!! I know people who could break a hammer! Needless to say they are off the list of people I would consider lending tools too. That list grows smaller as I age. Ha

[antique diver]

"Just because someone owns tools doesn't make them a mechanic."

You got that right!!! I know people who could break a hammer! Needless to say they are off the list of people I would consider lending tools too. That list grows smaller as I age. Ha

Hey, wait a minute... I've broken a hammer... are you talking about me?

[swimjim]

"Just because someone owns tools doesn't make them a mechanic."

You got that right!!! I know people who could break a hammer! Needless to say they are off the list of people I would consider lending tools too. That list grows smaller as I age. Ha

Hey, wait a minute... I've broken a hammer... are you talking about me?

I have a sneaking suspicion that in your case it was a fluke. S**t can happen to anybody. But some people seem to draw it toward them.

[simonbeans]

The visual inspection of tanks has and always will be a debatable issue. For good or bad, both federal law and current scuba dive store requirements obligate us who use cylinders that hold compressed gases. A few years ago I took the PSI class so that I could save myself the $15 to whatever price the local dive shop charged for this inspection. With too many tanks, for me this was a financial decision. From this class I also realized that the visual inspection process is not entirely black or white. There is a gray area. Peering through a small hole into a cylinder is problematic at best when determining the depth of bits. I was also taught to enlist the opinion of another inspector if I suspected a possible failure of a particular tank in question.

To suggest however that the inspectors and process is a “Three Stooges” endeavor is not warranted. PSI and others have specific standards. It would be ideal if they can be applied with certainty, but that is not always the case. I agree that to condemn this tank in question requires a bit more investigation. Specifically, a cleaning, be it sand blasting or tumbling to remove any materials that could obscure the suspected pits. The method Luis has used with sonic or whatever equipment is ideal albeit beyond the financial ability of most dive shops.

So the debate will continue about visuals. I have my opinion and you have yours. But in this case, Larry, Curly and Moe should remain on the movie screen and not be involved in scuba tank inspections.

[captain]

High pressure tanks have been in use for over 150 years with an outstanding safety record by following the Compressed Gas Association standards. The early days of scuba resulted in some tank failures mostly because of water being introduced in to tanks by compressor systems that were not designed with proper filtration and water separators plus a 5 year inspection cycle that gave enough time for undetected water to result in a failure.
The sucba industry came up with the yearly inspection, a good idea, pop off the valve look inside for water, none found good to go. Aluminum tanks were developed that for the most part were much better at resisting the effects of water and compressors systems were up graded to better eliminate water.
All was good until Bill High, a diver and from what I have read of him not a mechanical engineer saw a way to profit from the CGA standards by first convincing the scuba industry that they needed the service he provided and later the whole of the compressed gas industry.
What should be a simple process has become what this thread is about. A person who we shall assume is trained to do his job at a DOT certified requalification facility inspected and hydro tested this tank and deemed it safe for use by stamping the facility's RIN and test date on it.
Who is to say that if visual inspection is subjective that this persons opinion that the tank passes should be over ridden by an equally trained inspector unless some empirical evidence can can be shown to prove that the tank fails. If the first person inspecting this tank had went to another inspector for a second opinion "before" passing the tank I would have no problem but apparently the first inspector felt confident enough in his inspection to pass it.
Such is what has become of the process. One inspector doesn't trust the others inspection, one shop doesn't accept anthers VIP sticker and you know who is caught in the middle.
Lastly, if this tank is so border line that a decision can't be reached I venture to say that the likelihood of some catastrophic failure is astronomically remote.
Sorry if some don't like my opinion of the process but opinion is what the process is all about and it is a flawed process.

[Bryan]

Lastly, if this tank is so border line that a decision can't be reached I venture to say that the likelihood of some catastrophic failure is astronomically remote.
Sorry if some don't like my opinion of the process but opinion is what the process is all about and it is a flawed process.

Agree 100%

[1969ivan1]

Captain is a wise man. This thread should be highlighted over on Scubabrd. A lot of folks over there could learn from these sage words of Captain.

[swimjim]

Captain is a wise man. This thread should be highlighted over on Scubabrd. A lot of folks over there could learn from these sage words of Captain.

In a perfect world that would be the case. But it is more likely that it would draw criticism from the "experts?" who proliferate that board. They are better left to their lectures on adjusting the IP on a second stage.

[ebj]

Captain,
Thank you for the history lesson! Now I know "the rest of the story". It's amazing how we have allowed folks to profit in this industry from self serving regulations. I recently had a steel 200cf oxygen tank hydro'd, painted, inspected, new valve installed, and filled with aviation oxygen. Total cost was a little over $42 tax included! Try to get all that done to an older steel scuba tank and then fill it with air. Not for that price.