Had a customer come into the LDS I work with, and he asked for a fill. Having never seen this person, he was asked for a C-card. No problem so far, all standard fare. The shop owner was busy and asked if I would look after the fill. When I hooked up the tank, it was completely empty; I then mentioned this to the customer who said it must have leaked out on the way, with the valve rolling open in the trunk. Rather than filling it I told him we should look inside, the VIP was expiring in 2 months, and now might be a good time to do it before the spring thaw. He moaned and said it really wasnt necessary, but very reluctantly agreed.
When I removed the valve and looked inside, I saw a small puddle of dark liquid on the bottom of the tank, and the smell coming out of the tank was very familiar. Using a stick to get a sample, it turned out to be oil. I asked him where he filled the tank last, and he replied that he has been using it for filling tires, and has been filling it off a standard garage compressor. The tank and valve were filthy with oil! When we told him it would cost to get the tank and valve completely cleaned and suitable for breathing air use again, he said no thanks and took his tank with him empty.
We called the other dive shops and alerted them, they all called back later that day and said he had shown up.
This is why an empty tank is a red flag, we never know and the liability insurance only covers us if we act with due diligence.
