Tank explosion kills one - Cozumel

[Scubadude_LA]

I was under the impression that a hydro facility must condemn any tank that failed hydro and that vis was another issue. For example, a steel tank failing VIS that needs a tumble, followed by a hydro and then all good. VIS is a scuba industry thing not DOT if I'm correct.
But I think VIS lacks safety, IMO many VIS inspections at many shops aren't worth squat, drop a light, yeah looks ok (according to part time college student), new valve o-ring maybe, and slap on a sticker and pump to 3200 for a cool down and a $10 sticker fee. This is good in a way since any flooding, mass corrosion, etc should be spotted.
I think AL tanks should require eddys more often due to sustained load crackingk but that could lead to a great deal of false positives too. Unless grossly abused, seems like steels are more forgiving.

Disclaimer: Don't trust everything you read on the internet...

Edit: If we really are concerned and are somewhere and see some nasty looking tanks, shoot a pic, spread awareness. The pics I posted were no where near the worst in the bunch on that trip. In hindsight, I hope there were no incriminating markings on an otherwise ok tank that just looked tired, just trying to make us aware. But I think it can be an issue over and above explosions, like clogging of 1st stage filters, etc.

 

[nadwidny]

Disclaimer: Don't trust everything you read on the internet...

And nothing you hear from a dive shop.

 

[flots am]

It's been my experience that any operation that is accredited to do a certain type of testing isn't allowed to make an interpretation ie "condemning". They can only report on the results and whether or not the analysis meets standards ie "fail" (actually it should be "Fails to meet standards" since "fail" alone is apparently an interpretation). I believe this holds true for hydrostatic testing.

Hydro is different.

If a cylinder fails hydro, the testing facility is required by law to render the tank unusable.

 

[redacted]

Hydro is different.

If a cylinder fails hydro, the testing facility is required by law to render the tank unusable.

Yes, but it seems to me you can (or must) also condemn a tank during an annual VIS. With most shops, the owner is free to seek a 2nd opinion.

And then I suppose you also sell tanks. I'm not sure I would tank my tank to a hydro facility that also profits from the sale of tanks!!!

 

[captain]

Yes, but it seems to me you can (or must) also condemn a tank during an annual VIS. With most shops, the owner is free to seek a 2nd opinion.

And then I suppose you also sell tanks. I'm not sure I would tank my tank to a hydro facility that also profits from the sale of tanks!!!

Condemn and fail are two different things. A scuba shop doing a yearly vis can fail a tank but can't condemn ( render unusable) by some method such as drilling a hole in it or Xing out the DOT specification without the owners permission. A DOT licensed hydro facility can condemn when doing the required 5 year requalification (hydro).

 

[WB2GLP]

Hydro is different.

If a cylinder fails hydro, the testing facility is required by law to render the tank unusable.

That's incorrect.

Copy/Paste from PHMSA - Home

When a cylinder must be condemned the Requalifier MUST:

• Stamp a series of X’s over the DOT specification number and the marked pressure, or stamp ‘‘CONDEMNED’’ on the shoulder, top head, or neck using a steel stamp.

• For composite cylinders, securely affix to the cylinder a label with the word ‘‘CONDEMNED’’ overcoated with epoxy near, but not obscuring, the original cylinder manufacturer’s label.

• As an alternative to the stamping or labeling, at the direction of the owner, the requalifier may render the cylinder incapable of holding pressure.

 

[redacted]

Condemn and fail are two different things. A scuba shop doing a yearly vis can fail a tank but can't condemn ( render unusable) by some method such as drilling a hole in it or Xing out the DOT specification without the owners permission. A DOT licensed hydro facility can condemn when doing the required 5 year requalification (hydro).

But, in this case, we have a DOT licensed hydro facility (that is also a scuba shop) conducting a visual inspection. Let's say they find what appears to be cracks in the threads. The way I interpret regs is they would be required to condemn that tank. While it is usually a 5 year cycle for scuba tanks, if an owner decides to subject his tank to inspection more often, the DOT licensed facility will have to do its required job. No???

Whereas a normal dive shop would be limited to declining to pass the tank, unless the owner allowed more action.

 

[flots am]

That's incorrect.

Copy/Paste from PHMSA - Home

I actually know the regs and was going to copy and paste from the DOT because I knew someone was going to pop up and tell me I was wrong, but then I decided it wasn't worth the effort. I can see now, that on SCUBABoard, no nit is too small to pick.

So yes, Xs are just fine, however it does, for most divers render the cylinder unusable since only a moron would fill a tank that had failed hydro. My statement was meant to describe that the tank would be made so that it could no longer be used ("unusable"), not describe in detail the process for doing so.

Congratulations, you win all the Internet points for today.

flots.

 

[blanik]

interesting picture i took of a condemned cylinder, it's one of those infamous cylinders with the bad alloy that killed people a couple of years ago, it was stamped XXXXXXXX over the serial when it failed the hydro, the shop owner had it cut in half as a display, it's quite thicker than i expected

 

[NAM001]

My training says that vis inspectors can not render a tank unable to hold pressure on their authority. and only a hydro can mark a tank (indention stanping like a hydro stamp). A vis can not authorize the inspector to alter/obliterate the neck markings. What was recommended is that the customer signs a release of understanding that if the tank fails vis it will be made unable to hold pressure. That way it is being done by the owners request. This and payment is done/made before the vis is conducted. If the customer doesnt agree then they can take thier tank elsewhere. In regards to the vis,,,, the inspector is not to look for reasons to fail a tank but to pass a tank. If there is something that is unsure whether it is a pass/fail then you pass it or give the customer some/all money back and the tank and let them go to get a second opinion. Failures are to be undisputable falures.