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Ground-level Ozone Pollution

Revision to the Regulatory Definition of Volatile Organic Compounds – Exclusion of trans-1-chloro-3,3,3-trifluoroprop-1-ene

August 28, 2013 - EPA added trans-1-chloro-3,3,3-trifluoroprop-1-ene (also known as Solstice 1233zd(E), CAS number 102687-65-0) to the list of compounds excluded from the regulatory definition of volatile organic compounds or VOC. Evidence shows that Solstice 1233zd(E) is negligibly reactive in forming ground-level ozone. This action will allow states to remove regulatory controls on Solstice 1233zd(E) that are part of State Implementation Plans designed to help meet the ground-level ozone standards. Solstice 1233zd(E) is used in a variety of applications including as a solvent in aerosol and non-aerosol applications, as a blowing agent in insulating foams for refrigerators/freezers and hot water heaters and as a refrigerant in commercial chillers and waste heat recovery (Rankin cycle) systems.