Are CFC-replacements really ozone friendly?
The chemicals that are currently replacing CFCs are either HCFCs (hydrochlorofluorocarbons) or HFCs (hydrofluorocarbons such as R-134a). HCFCs have less chlorine in them and are less susceptible to the reactions that release chlorine in the stratosphere. But they are still ozone-depleting chemicals — they just destroy far less ozone than CFCs. For example, while CFC-12 has an ozone depleting potential rating of 1.0, HCFCs have ratings from 0.02 – 0.1. HCFCs will eventually be phased out by 2030, as stated in the Montreal Protocol. HFCs do not contain chlorine, so they don’t contribute to ozone destruction at all. However, since both of these groups are potent heat-trapping gases, they are a stop-gap measure, the lesser of two evils. Eventually, we are going to need a permanent replacement for all these kinds of chemicals.
