Final Decision to Retain the National Ambient Air Quality Standards for Particulate Matter (PM)
On December 7, 2020, after carefully reviewing the most recent available scientific evidence and technical information, and consulting with the Agency’s independent scientific advisors, EPA is announcing it will retain, without revision, the existing primary (health-based) and secondary (welfare-based) National Ambient Air Quality Standards (NAAQS) for particulate matter.
Read the the final decision. A summary fact sheet is below.