The U.S. Environmental Protection Agency (EPA) announced on December 14, 2012 that they had finished an update to the National Ambient Air Quality Standards (NAAQS) for fine particle matter (PM2.5). The annual health standard is now 12 micrograms per cubic meter, down from 15. Fine particle pollution includes soot, a diesel engine emission.
With new or more stringent national standards come local regulations to meet those standards. According to the EPA, fewer than 10 counties out of the more than 3,000 counties in the U.S. will need local actions to reduce fine particle pollution in order to meet the new standard by 2020, as required by the Clean Air Act.
In the counties that are expected to be impacted, it may take up to three years for local actions to be approved and implemented, but diesel equipment owners in these counties should stay tuned for regulatory developments that could impact their fleet. Both regular and planned revisions to monitoring of air quality by the EPA could find additional counties do not meet the new standard in the future.
Another NAAQS revision that could have a significantly broader impact later this year is the ground-level ozone standard. You may remember that revisions to this standard were delayed in September 2011, but the next scheduled statutory review of the ozone standard will be in October 2013 with new standards finalized by July 2014. Watch Emissions Hub for news on this expected revision as it develops.