What type of refrigerant is considered harmful to the ozone layer?

BFCs, or chlorofluorocarbons, are considered harmful to the ozone layer because they contain chlorine atoms. When CFCs are released into the atmosphere, they eventually reach the stratosphere, where ultraviolet (UV) radiation breaks them down, releasing chlorine. These chlorine atoms can then react with ozone (O3) molecules, leading to the depletion of the ozone layer. The ozone layer is critical for protecting the Earth from harmful UV radiation, and its depletion can have significant environmental and health impacts.

In contrast, hydrocarbons, HFCs (hydrofluorocarbons), and HCFCs (hydrochlorofluorocarbons) either have a much lower impact on ozone depletion or, in the case of hydrocarbons, do not contain chlorine at all. While HCFCs do have some ozone-depleting potential, they are not as harmful as CFCs and are being phased out as part of international agreements due to their environmental impact. HFCs, on the other hand, do not contain chlorine and do not contribute to ozone depletion, although they may have high global warming potential.