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Ground-level Ozone Pollution

Revision to the Regulatory Definition of Volatile Organic Compounds - Exclusion of 2,3,3,3-tetrafluoropropene

October 22, 2013 - The Environmental Protection Agency has issued a final rule that identified 2,3,3,3-tetrafluoropropene (also known as HFO-1234yf) as a chemical compound that will no longer be regulated as a VOC under the Clean Air Act. This will remove it from regulatory requirements related to controlling VOC emissions in order to meet the ozone NAAQS. EPA will add HFO-1234yf to the list of negligibly reactive compounds in EPA’s regulatory definition of VOC.

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