There is no legal reason for a VIS, but it is considered a added safety inspection. If you use a PADI shop, their retailer agreement requires the shop to only fill tanks that have a current visual inspection. The other agencies propably are the same.
It is actually a DOT requirement that a tank be visually inspected when the hydro is done, but they aren't required to put a sticker on the tank like we do in the scuba industry.
---------- Post added March 15th, 2013 at 03:31 PM ----------
I have a set of double AL80's that I bought brand new a year ago. They still look new have been in a freshwater lake 3-4 times and an lds's pool once. They have never been below 600psi since assembled. They are 02 cleaned. The vip expired in Feb so once I get a chance to drain the 36% that's in them now a new vip will be "needed". To do this the bands will have to be removed and reinstalled, the finely threaded isolator manifold unthreaded and rethreaded, and both valves pulled then reinstalled. Can anyone explain to me who all of this fiddling with my tanks will be beneficial to and why?
It is a PITA to do all of that. I've been taught that it takes a crack an average of 8 years to become an explosion. The idea of checking each year is that you have a couple of opportunities to catch the crack, instead of relying on the one visual that's done every 5 years at hydro to catch it. Some cracks are very small and if the inspector isn't paying attention they may miss them. There's only one thing to do, dive those tanks more often and get your money's worth out of them
---------- Post added March 15th, 2013 at 03:44 PM ----------
So, why do I have to get an annual VIS? Why do I have to pay for 2 inspections in the course of a tank requalification? Why does a VIS expire at the beginning of the indicated month? What qualifications are required of a hydro inspector? What qualifications are required of a shop visual inspector? Any documented references?
You don't legally have to get a vis each year, it boils down to what the person filling your tanks require, the industry norm is every year. It is even possible to have a current vis and have someone refuse to fill because the sticker isn't recognized, although I think that is rare.
The two inspections thing is between you and the shop, the hydro facility is supposed to vis the tank at hydro, although since they aren't providing a sticker the shop will probably charge you for the service. It's not a bad idea to look in or have someone else look in the tank after hydro though...last hydro I had left my tanks dirty as hell.
Expiring at the beginning of the month..who knows, another industry standard, but one I can't explain. Hydros expire at the end of the month.
Hydro inspectors are qualified by the DOT. Conducting a hydro without a DOT code or with an expired one is a serious crime. The 4 digit code or symbol in between the month and year of hydro indicates the hydro facility that did the test. The number is read clockwise starting at the top left number. You can look up the code on the DOT website.
Visual inspectors are taught under certification agencies that are similar to scuba certifications, as in they all have a syllabus that is accepted by industry standards and rely on DOT, CGA and other regulations.
I don't have documentation that is in an electronic format, but I am a cylinder visual inspection instructor.
