Re: huh? buy tanks of O2?

  I thought the ozone generator changed the O2 to O1 from normal air in the room.

Yes, and UV and hot corona systems also generate nitrogen and sulfur oxides if air is used.

The main issue though is if using ozone internally then you need to know the ozone concentration. The only way to know the concentration is to have a known concentration of oxygen to begin with, which in this case would be 100% oxygen as opposed to the variable oxygen concentrations of air.

In short you are OK with air for external use, but not internal use. Using air for external use will just lower the overall ozone concentration due to lower oxygen levels to begin with.