Which refrigerant has a high ozone depletion potential?

CFCs, or chlorofluorocarbons, have a high ozone depletion potential because they contain chlorine atoms, which are highly effective at breaking down ozone molecules in the stratosphere. The ozone layer protects the Earth from harmful ultraviolet (UV) radiation, and when CFCs are released into the atmosphere, they can eventually reach the stratosphere where UV radiation causes them to release chlorine atoms. Each chlorine atom has the capacity to destroy thousands of ozone molecules, leading to significant depletion of the ozone layer.

In contrast, HFCs (hydrofluorocarbons) and HCFCs (hydrochlorofluorocarbons) have been developed to replace CFCs and have little to no ozone depletion potential. R-134a, which is a specific type of HFC, also does not contribute to ozone depletion. Therefore, CFCs are recognized specifically for their harmful impact on the ozone layer, making them the correct choice in this context.