All about cylinder inspections & training

[Drew Sailbum]

There are several reasons why a shop might legitimately require a new visual exam such as:

• tank is brought in completely empty
• previous visual inspection has expired (usually 12 months)
• unusual sound such as rattling or sloshing
• foul odor from cylinder gas
• evidence of contamination (rust/oil) on your reg's first stage filter
• cylinder is leaking from neck
• previous exam was invalid
• evidence of exposure to excessive heat or fire
• cylinder or valve has suffered external damage (dent, rust, bulge)
• cylinder is unusually heavy
• previous inspection sticker has been altered or destroyed

A previous exam may have been invalid if the cylinder markings are in some way deficient. This may result if the previous hydro examiner failed to overstamp an old aluminum cylinder that was manufactured under a Special Permit. Until the cylinder is overstamped 3AL, if eligible, it may not be filled. Certain cylinders manufactured under Special Permits are not eligible for overstamping and must be removed from service in the USA.

It may be that none of these apply in this case.

 

[WVMike]

What type of certification is required to do yearly inspections on tanks?

How does one get certified?

Does anyone have experience with eddy current testing?

TIA

mike

 

[pdoege]

There are no laws regulating the inspection of scuba cylinders. The new luxfer cylinders are the one exception to this. The industry is self regulating.

As a result, many scuba shops that do inspections do a pretty spotty job.

Anyway, training is provided by Professional Scuba Inspectors. www.psicylinders.com

The course is not all that cheap, but it does cover a lot of material and produces decent inspectors.

Eddy current testing appears to be frowned upon by most manufacturers. It is felt that it is not needed and that it generates a lot of false positives. The manufacturers of the eddy testers can provide testing on their units.

I would take the PSI course and be done with it.

Peter

 

[rmediver2002]

What type of certification is required to do yearly inspections on tanks?

How does one get certified?

Does anyone have experience with eddy current testing?

TIA

mike

Hey Mike,

1) there is no level of certification required by DOT for annual vip inspection, in fact annual inspection is not required. It is however the industry standard for diving and a very cheap and effective preventative measure.

2) The most popular agency for VIP training is PSI www.psicylinders.com but it appears the website is down right now...

3) Eddy current testing is a great tool when properly used, it can be of great assistance to a tech if for nothing else than to make them look at a paticular area more closely.

Eddy current testing came into it's own when used to check older aluminum tanks made from 6351 alloy, some of these tanks have ruptured having problems with cracking...

Newer tanks are made from 6061 alloy and have not to date suffered the same problems. There are several companies who are now making eddy current devices specifically for the 6061 since the units designed for the 6351 were found to give inaccurate readings when used with the 6061 alloy.

Here is a press release from Luxfer on the issue:

http://www.luxfercylinders.com/news/releases/20000717b.shtml


Jeff Lane

 

[SDAnderson]

There are no laws regulating the inspection of scuba cylinders. The new luxfer cylinders are the one exception to this. The industry is self regulating.

Hydro's are essentially required by law, annual visuals are not. I don't know anything about a required visual inspection of any Luxfer scuba cylinder, except in connection with a hydro.

As a result, many scuba shops that do inspections do a pretty spotty job.

Ya, hey der! Know your tech!

Anyway, training is provided by Professional Scuba Inspectors. www.psicylinders.com

They are the generally recognized authority.

The course is not all that cheap, but it does cover a lot of material and produces decent inspectors.

Ya, hey der! And it involves spending a fair amount of money on tools and paraphelia that aren't included in the class cost.

Eddy current testing appears to be frowned upon by most manufacturers. It is felt that it is not needed and that it generates a lot of false positives. The manufacturers of the eddy testers can provide testing on their units.

Eddy testing is warranted on the 6351 alloy tanks, which are still legal, although I don't know why anyone would still be pressurizing them.

I would take the PSI course and be done with it.

Unless you have a bunch of cylinders to inspect each year, I wouldn't suggest doing your own inspections. No matter how well trained, inspections require both skill and art and that means practice to remain effective. Inspecting a half-dozen tanks each year just isn't enough. For most divers, it's better to save the class money and have someone who they trust look their tanks over for them. Just as there are lots of shops that won't fill 6351 tanks, no matter what the hydro and vis reports say, many shops won't fill tanks if they don't recognize the visual inspector. What a drag to spend the time and money learning how to do your own, only to find out that your shop won't let you.

 

[WVMike]

Peter, Jeff, and Steven,

Thanks for the good info and advice. I am a believer in letting professionals do their jobs, and I also have been a supporter of my LDS.

Here is the dilemma, my LDS is closing the doors. Internet sales helped do them in..... but that is another thread.

Now with the nearest dive shop 1 1/2 hours away and not knowing anyone there. Diving has become more difficult. Plus I do worry that the so called experts might not really be any more qualified than me.

So I am exploring options, like getting a compressor and learning to service my own gear. I definitely would want to do it right (ooops another thread) or not do it at all.

Anyhow, thanks again

Mike

 

[pdoege]

The new hoop wrapped tanks must be visual'd by a PSI trained inspector every year and hydroed every 3 years. The cylinders are to be destroyed after 3 years.

Sort of a pain.

http://hazmat.dot.gov/exemptions/E12479.pdf

Page 4 has the inspection requirements.

Peter

 

[SDAnderson]

The new hoop wrapped tanks must be visual'd by a PSI trained inspector every year and hydroed every 3 years. The cylinders are to be destroyed after 3 years.

Sort of a pain.

http://hazmat.dot.gov/exemptions/E12479.pdf

Page 4 has the inspection requirements.

Peter

Oh, yeah. I remember these things. Very high pressure (hard to get a full fill), as expensive as steel tanks and a limited lifespan - although I thought it was something like 10 or 15 years, not 3. I don't remember what the marketing gimmick was, other than they were weird. Did anybody actually buy any of them?

 

[pdoege]

Reefraff's memory is correct, the tanks have to be condemned after 15 years, not 3. Thought one thing and typed another.

I believe that these tanks came out at DEMA last year. 4500psi IIRC. Nobody around here pumps that high. Well, none of the recreational shops anyway.

I think the AL63 sized bottle actually held 95ft^3. The idea was that you could dive a light tank and still get nice bottom time.

Peter

 

[ScubaDadMiami]

. . . these tanks came out at DEMA last year

While I didn't waste much time checking them out, I did see them at DEMA. They had a video playing at the booth, showing the wrapping process in the factory. A local shop in my area also has one.

One incarnation of them or another has been around for some time now. They just have never caught on in the diving industry due to expense and limited life span issues (especially considered against the popular AL80).

Though I don't recall for how long, they do have a maximum life span and are condemned once reaching that time. There is not a way to use them after even by passing a hydro test.

I have never seen them in the water. Mostly they are used by fire rescue types due to the gas they can hold relative to their weight (out of the water).