Question

how is ozone depleting when it is formed by UV rays and oxygen only

Answer 1

n the lower atmosphere, CFCs are protected from ultraviolet radiation by theozone layer itself. CFC molecules thus are able to migrate intact up into the stratosphere. ... Free chlorine atoms then react with ozone molecules, taking oneoxygen atom to form chlorine monoxide and leaving an ordinary oxygen molecule.

Answer 2

ODS (Ozone Depleting Substances) are comfortably broken down by the strong UV light and the resultant chemical is chlorine and bromine. Chlorine and bromine are known to deplete the ozone layer at supersonic speeds. They do this by simply stripping off an atom from the ozone molecule. One chlorine molecule has the capability to break down thousands of ozone molecules.