EPA tightens standards for soot pollution - Article Photos 1/2

FILE- In this April 17, 2012 file photo, Environmental Protection Agency (EPA) Administrator Lisa Jackson gestures during an interview with The Associated Press at EPA Headquarters in Washington. In its first major regulation since the election, the Obama administration will impose a new air quality standard that reduces by 20 percent the maximum amount of soot released into the air from smokestacks, diesel trucks and other sources of pollution. The Environmental Protection Agency is set to announce the new standard on Friday, meeting a court deadline in a lawsuit by 11 states and public health groups. (AP Photo/Kevin Wolf, File)