Scored four steel tanks.

[captain]

The give up point is after all the rust is out and you can see what's left. I have seen some pretty bad ones that cleaned up and passed.

[luis]

As Captain says the rust needs to be cleaned out in order to be able to inspect for pits. The pass-fail criteria are based on pit depth or if there is a series of pit in a line. The rust is normally the cause of the pits, but technically it in itself is only an indirect indication of what should be used to fail a cylinder.

There is a specified maximum pit depth (I can look it up), but inside a tank how to measure the pit depth is more of an art than a precise science.

The CGA (Compressed Gas Association) documents have fairly detail pas fail criteria, but in real life a lot of it becomes a bit of a judgment call.

Then you have a large number of dive shop inspectors who have little or no training and don’t own a copy of the CGA documents and they are going to be conservative based on lack of knowledge.

As mentioned, to properly inspect a tank the rust should be removed first, but that cost money and it may not be worth it. The decision to clean a tank in part should come from experience, but failing without cleaning it is just a short cut to save money or the trouble.

[8dust]

Thanks guys.

Either of you remember that j-valve rebuild video, or have I just lost my mind?