Halogenated organic compounds Sit out problem

Replacement compounds for CFCs are HCFCs and HBFCs. Although HBFCs were not originally regulated under the Clean Air Act, subsequent regulation added them to the list of class I substances and they were phased out in 1996 because of 

Nevertheless, a significant proportion of HCFCs do break down in the stratosphere and they have contributed to more chlorine build-up there than originally 

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