Re: Violet Ray
The last thing you want near a human is ozone. It's toxic at the smell threshold. With luck the sort of machine you refer to smelled of oxides of nitrogen rather than ozone (not that you want to breath them either, but at least they're less toxic).
This plasma device sounds interesting, but will it fail in the same way as aqueous bactericides? You can't zap the blighters if they've got a protective coat around them. In the case of skin, it's not a shiny surface with a thin film of bacteria on it. The surface of skin is a messy, porous construction of dead skin cells with bacteria in the spaces between them. Those bacteria are well protected. That plasma had better be able to penetrate further than 25 micrometres. I'd rather my would-be surgeon scrubbed with povidone iodine.