Solo Cave Diving: Equipment Configuration

[Tracy]

Yea, that is also what the shop said. Like most, I didn't assemble the valves as the tank came to me full. So I'd venture the guess that almost nobody knows how much lube is on their valve o-rings. The point here is it's possible to extrude that o-ring either through incompetence or bad luck. I guess the up side is it did fail pretty soon after fill (although it was almost a week). So if you have tanks you've been using for a bit you can be confident they should continue to be fine, but clearly, the risk is always there.

Anything is possible, but the odds are in your favor. The old 7/8 valves on the Norris HP tanks are known to extrude if you don't use a 90 duro o-ring. They had a very shallow o-ring land. They need to be wrench tight with a high duro or they will fail almost every time.
Most other tanks are fine being hand tight.