EPA Proposes Retaining SOx NAAQS But Weighs Implementation Changes

摘要

EPA is proposing to retain its existing primary health-based sulfur oxides (SOx) national ambient air quality standard (NAAQS) but is weighing potential changes to its implementation, including potentially easing compliance by altering the formula for how the agency determines whether an area is attaining or violating the NAAQS.In a notice signed by EPA Administrator Scott Pruitt May 25 ahead of its publication in the Federal Register, the agency proposes to keep the existing standard of 75 parts per billion (ppb) of sulfur dioxide (SO2), averaged over one hour - a standard first issued in 2010. SOx refers to a group of gases of which SO2 is the most prevalent in the atmosphere and for which EPA has the largest amount of scientific evidence on the pollutant's adverse health effects.