8 replies to this topic

[Laura]

Hi everyone,

There is going to be a PSI course being offered in my area this spring. After hearing Walter's tale of finding a dead bug in his tank, after it was supposedly inspected, I am thinking of taking this course.

Do you have to be a dive professional to take the class? Has anyone taken this class, and if so what is your opinion? Is it worth the cost?

Thanks!
Laura

[Walter]

Anyone can take the course. It's worth the time and money, especially if Chris will be your instructor.

[Genesis]

Worth it if you're going to do your own VIS inspections (and can get the stickers)

Otherwise, perhaps good for learning, but the practical application is another matter.

[Walter]

PSI will sell stickers to their graduates and you can always print your own.

[ScubaDadMiami]

Walter is correct. I am a PSI inspector. PSI sells stickers and some inspection tools, too.

Even if you never actually become an inspector for a living, it is a great education to have.

[Desert_Diver]

Ummm, curious question. Maybe someone could ask the PSI folks for me?

I've seen a surprising number of shops online in the last several months with a large warning banner stating WE WILL NOT FILL TANKS WITHOUT A VIP+ STICKER.

None of my tanks have the VIP+ sticker 'cos none of 'em are the type of aluminum with the funky exemptions that had all of the stress cracks. As far as I've been able to tell, steel tanks never had the cracking problem, just rust, and I'm not even sure an eddy test will *work* on a steel tank. None of the shops I deal with in Phoenix have the eddy tester, so they can't tell me for sure.

Is this just more (expletive deleted) from dive shops so that they can finance the overly expensive eddy tester that they purchased? The test requirements from the DOT are based on COMMERCIAL TANKS that are filled and emptied weekly, not scuba tanks that are filled maybe once every few months, even less in my case. I pull the valves out of my steel tanks and clean 'em once a year due to rust concerns, but with the useage they're getting, they'll hit their 5 year hydro LONG before the'd actually *need* an eddy test. Same with my little aluminum ponies, which have only been filled twice.

1) is VIP *required* by the DOT for tanks that aren't the poor alloy(s)?

2) will an eddy test *work* on a steel tank, and similarly is it required by the DOT?

If both answers are a resounding NO, then I'll make sure to never do business with a shop that insists on VIP+ for every tank they fill, regardless of whether it makes any sense. That would mean they have an anal <> cranial inversion, and I wouldn't trust a shop like that. Ever.

[maninthesea]

Desert_Diver

You can not eddie current test steel tanks. However some states(Florida I belive is one) mandate that alluminum tanks are eddie current tested. So it depends on where you are getting the fill. Oviously not a requirement in AZ.
The DOT mandates that tanks are visually inspected at the time of Hydro. They recomend tanks are visually inspected every year. The scuba industry has wisely followed that recomendation.
Eddie current testing is recomended by the two agencies that give inspection training PSI and TDI. It is gaining popularity. One thing holding it back in some places is the cost of the aparatus. If there are two shops in compitition and one starts eddie current testing they will need to charge more to recover the cost of the machine. Most divers are cheep and would go to the other shop where their tank will be cheeper to inspect and is more likely to pass for another year. Shop 1 loses customers.
Although cyl failures are rare they generally occur while the tank is being filled and can cause a lot of damage and even death the the filler. I dont blame anyone for wanting to make sure they dont have an accident on their property.
Out of curiosity how much is the going rate for eddy current tests?

Cheers
Jim

[peterbj7]

Isn't it the case that for aluminum tanks a hydro test doesn't usually tell you a lot, whereas a visual inspection, following proper cleaning and preparation of the inside of the tank, can reveal fine cracks?

I remember seeing at the premises of a manufacturer of tank testing equipment (Miami area) an aluminum tank that had been sawn in half, with one half left exactly as was, and the other half cleaned with a sort of "disclosing liquid" that stripped away the oxides and left the bare metal. The untreated half looked completely normal and safe, the other half was covered in fine crazed cracks which showed that the metal was beginning to crystalise.

The same people said that with steel tanks the imperatives are reversed - although visuals are important in revealing developing rust, the hydro shows whether the tank is beginning to lose its elasticity, which for a steel tank is curtains.

Although common sense would suggest steel tanks would corrode and fail sooner than aluminum, in all my years diving I've never had worse with a steel tank than that it needed to be tumbled to remove fine rust, and I've owned quite a few steel tanks, whereas I've had two aluminum tanks fail visuals. That's fail as in "sawn in half".

[maninthesea]

Peter
I would have to agree that defects in an AL tank will not usually cause it to fail hydro. I have seen tanks that passed hydro then failled visual afterward. Which in itself is bad becuase the hydro facility is supposed to do a visual. I have a tank that failed due to internal pitting, I had the EOD guys blow it up and you can see where the tank ripped from pit to pit and you can also see that the pits were much deeper than you wuold conclude by looking at them from the surface.
My experience with Steel Vs Al is that steel tanks that are used a lot(3-5fills per week) will not usually make it thru the 2nd hydro. They fail on elasticity. On the other hand AL tanks that are in heavy use (at least 1 dive a day) hardly ever fail hydro. They usually fail a visual from internal pitting(caused by someone sucking the tank dry underwater) or from Galvanic corosion around the oring seal on the neck causing them to need to be serviced once a month or so for neck leaks.

Cheers Jim