WASHINGTON (AP) — In its first major regulation since the election, the Obama administration on Friday imposed 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.

Environmental Protection Agency Administrator Lisa Jackson said the new standard will save thousands of lives each year and reduce the burden of illness in communities across the country, as people “benefit from the simple fact of being able to breathe cleaner air.”