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Ground-level Ozone Pollution

Revision to Regulatory Definition of Volatile Organic Compounds - Exclusion of of 1,1,2,2-Tetrafluoro-1-(2,2,2-trifluoroethoxy) ethane (HFE-347pcf2)

August 1, 2016 - EPA added 1,1,2,2-Tetrafluoro-1-(2,2,2-trifluoroethoxy) ethane (also known as HFE-347pcf2; CAS number 406-78-0) to the list of compounds excluded from the regulatory definition of VOC.  Evidence shows that HFE-347pcf2 is negligibly reactive in forming ground-level ozone. This action will allow states to remove regulatory controls on HFE-347pcf2 that are part of State Implementation Plans designed to help meet the ground-level ozone standards. HFE-347pcf2 is used in a variety of applications as a replacement for precision cleaning.  

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