Oxygen clean stickers and annual visual stickers are not required by the DOT. These practices were brought about by the scuba industry itself. Most shops embrace these practices because it makes the sport a little safer and it keeps the shop employees employed while at the same time confusing the crap out of everyone. Don’t get me wrong. I’m all for safety, but too many shops have too few people that know what’s fact or fiction.
The DOT requires hydrostatic recertification of scuba cylinders every 5 years which includes a visual inspection at the time of hydro. Other than a current RIN stamping around the neck, nothing else is required by the DOT. Oxygen cleaning is required if a cylinder is being used for oxygen, but no stickers are required by the DOT.
Sticker requirements change from shop to shop as do fill policies. Some shops refuse to fill aluminum tanks older than 1990 while others will as long as (if required) a VE stamp follows the RIN stamp. The DOT only dictates whether a cylinder can or can’t be placed into service. It does not require a shop to fill any and all tanks that meet the DOT standards.
I agree with SeleneOneill that the Nitrox wraps avoid confusion when dealing with a fleet of rental tanks.
I pull all stickers when I do visuals. Stickers can easily hide dents and corrosion. Besides, a decade’s worth of visual stickers will confuse the crap out of anyone. That 1985 NASDS VIP sticker is cool, but it should have been scraped off in 86.
I posted a few pics of things I’ve caught wrong with cylinders that came in for service or fills. Good for a laugh or two.