We are a hydro facility. A cylinder failing hydro can not be made incapable of being filled without the owner's consent. i.e. drilling a hole or destroying the threads. We are required to X out the DOT information, (not the SN#). If I fail a cylinder on visual which is required, I X out the DOT info. The hydro facility is required to perform a visual as well as the hydro test.
Also a point is if a dive shop fails the VIS they are not authorized to X out the DOT info, only a facility with a requalifier identification number, (RIN) may do that. The proper handling of a failed vis by a dive shop is to simply reject the cylinder unless they hold a Visual RIN number. Of course RIN numbers don't come cheap as you have to submit to an audit by and independent inspection agency every five years. Paperwork retention and requirements as well as periodic training with documentation. Oh and the DOT can come knocking at your door any time they want to perform a review of you systems. We have had three such visits over the last 20+ years!
Also a point is if a dive shop fails the VIS they are not authorized to X out the DOT info, only a facility with a requalifier identification number, (RIN) may do that. The proper handling of a failed vis by a dive shop is to simply reject the cylinder unless they hold a Visual RIN number. Of course RIN numbers don't come cheap as you have to submit to an audit by and independent inspection agency every five years. Paperwork retention and requirements as well as periodic training with documentation. Oh and the DOT can come knocking at your door any time they want to perform a review of you systems. We have had three such visits over the last 20+ years!