EPA Proposes To Tighten Annual PM2.5 Limit But Retain Daily Standard

EPA is proposing to tighten its health-based annual limit for fine particulate matter (PM2.5) to a level lower than that set by the Obama administration in 2012 but is not planning to tighten its 24-hour limit, disappointing environmental and public health groups and disregarding agency science advisers who pushed for a tougher daily value. In its long-awaited proposal to revise national ambient air quality standards (NAAQS) for fine particles, the agency proposes to lower the current “primary,” or health-based limit...