In response to a court order, the U.S. Environmental Protection Agency (EPA) Friday finalized an update to its national air quality standards for harmful fine particle pollution, including soot, setting the annual health standard at 12 micrograms per cubic meter. By 2020, 99 percent of U.S. counties are projected to meet revised health standard without any additional actions.
A map released by the EPA shows seven counties in the country, all in Southern California, are not expected to meet the standards by 2020.
The new standards will reduce by 20 percent the maximum amount of soot released into the air from smokestacks, diesel trucks, buses and other sources.
The EPA announced the new standard Friday, meeting a court deadline in a lawsuit by 11 states and public health groups.
The new annual standard will be 12 micrograms per cubic meter of air, down from the current 15 micrograms per cubic meter.
Environmental and business groups have battled over whether the new standard will protect public health or cause job losses.