It really only applies to the Worthington cylinders on their first or second test. It also really only applies to tanks that were babied or not stored full.anyone know the round out procedure if scubaa tank fail when being hydro tested.I saw they can rehydro the tank someplace !
Worthington used heavy galvanizing and it would show the tank as brittle and fail. In reality, the tank was fine, their coating was brittle. So the round out procedure stretched out the galvanized coating before the actual test. If you have a tank that has been used a lot, or a tank that has been cave filled its whole life, this never even comes into play.
With the current age of any Worthington cylinders coming to test, it almost isn't even a thing anymore.