Mar 11, 2005 — The Environmental Protection Agency has set new limits on smog and soot pollution. The aim is to help tens of millions of people who live downwind from the dirtiest coal-fired power plants in the East, South and Midwest. The EPA's new "Clean Air Interstate Rule" covers 28 states. The regulation apparently calls for most of them to cut nitrogen oxides and sulfur dioxide that wind can carry across state lines.