EPA proposes tighter particulate air pollution standards

摘要

Paniculate matter (PM) is one of six criteria pollutants regulated by National Ambient Air Quality Standards (NAAQS). These standards are twofold: a primary standard protects human health, and a secondary standard protects crops, ecosystems, and other forms of "public welfare." The U.S. Environmental Protection Agency (EPA) last revisited the PM standards in 2006. Now, in response to a court order mandating action on the overdue review of these rules, the agency has proposed a stricter set of new standards.