The Environmental Protection Agency (EPA) has published a final rule revises the definition of volatile organic compounds (VOCs) under the Clean Air Act (CAA). This revision adds four chemical compounds to the list of compounds excluded from the definition of VOC on the basis that each of these compounds makes a negligible contribution to tropospheric ozone formation. These compounds are four hydrofluoropolyethers (HFPEs) commonly known as HFE-134, HFE-236cal2, HFE-338pcc13, and H-Galden 1040X/ H-Galden ZT 130. If an entity uses or produces any of these four HFPE compounds and is subject to the EPA regulations limiting the use of VOC in a product, limiting the VOC emissions from a facility, or otherwise controlling the use of VOC, then the compound will not be counted as a VOC in determining whether these regulatory obligations have been met. This final rule may also affect whether any of these compounds is considered a VOC for state regulatory purposes, depending on whether the state relies on the EPA’s definition of VOC. The final rule is effective on March 14, 2013.

As background, the CAA requires the regulation of VOCs for various purposes and specifies that the EPA define the meaning of “VOC,” and what compounds shall be treated as VOCs for regulatory purposes. The policy of excluding negligibly reactive compounds from the VOC definition was first set forth in 1977 in the “Recommended Policy on Control of Volatile Organic Compounds”. The EPA uses the reactivity of ethane as the threshold for determining whether a compound has negligible reactivity. Compounds that are less reactive than, or equally reactive to, ethane under certain assumed conditions may be deemed negligibly reactive and therefore may be exempted from the regulatory definition of VOC. For all four compounds, EPA proposed that (a) these chemicals qualify as negligibly reactive with respect to their contribution to tropospheric ozone formation, and (b) any non-tropospheric ozone-related risks associated with potential increased use are adequately addressed by other existing programs and policies.

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