Germicidal UV-C light kills pathogens by a process called ‘irradiation’ – which disables the DNA of the bacteria, and effectively kills it. It is important to understand that Germicidal UV-C only treats the air which is exposed to this UV-C light i.e. only air which passes inside the purifier will be treated.
When Ozone is created by UV, it is not the UV light which kills pathogens. Instead, the UV light is used to create Ozone from a small portion of the Oxygen in the ambient air. The Ozone is then dispersed into the area needed treating, where it provides odour and germ control by a processes called ‘oxidation’ (learn more about Ozone here).
So in summary; Germicidal UV-C treats air which is exposed to the light, whereas a UV Ozone generator will use the UV light to create Ozone, and it is the Ozone which provides the treatment – not the UV light itself.