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Particulate Matter (PM) Pollution
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2012 National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM)

2012 National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM)
Basic Information
Legal Authorities
  • 42 U.S.C. §7403
Federal Register Citations
  • 78 FR 3086
  • 77 FR 38890
  • 77 FR 38760
Code of Federal Regulations Citations
  • 40 CFR Part 50
  • 40 CFR Part 51
  • 40 CFR Part 52
  • 40 CFR Part 53
  • 40 CFR Part 58
Docket Numbers
  • EPA-HQ-OAR-2007-0492
Effective Date
  • March 18, 2013

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources

Rule Summary

In 2012, based on EPA’s review of the air quality criteria and the national ambient air quality standards (NAAQS) for particulate matter (PM), the EPA revised the annual PM2.5 standards, and made related revisions in:

  • data handling conventions
  • the Air Quality Index (AQI)
  • the ambient air monitoring, reporting and network design requirements
  • regulations for the prevention of significant deterioration (PSD) program

The EPA retained the existing primary (health-based) and secondary (welfare-based) 24-hour standards for PM2.5 and PM10, without revision.

Rule History

03/20/2017 - Technical Correction to Equation 2 in Appendix N:  Final Rule
 

08/11/2016 - Technical Correction to Equation 2 in Appendix N:  Direct Final Rule and Parallel Proposal

01/15/2013 – Final Rule

06/29/2012 – Proposed Rule & Correction

Additional Resources

Fact Sheet Technical Correction to Equation 2 in Appendix N:  Final Rule

Fact Sheet Technical Correction to Equation 2 in Appendix N:  Direct Final Rule and Parallel Proposal

Regulatory Impact Analysis for the Final Revisions to the National Ambient Air Quality Standards for Particulate Matter

Fact Sheets and Additional information Regarding the 2012 Revision to the Particulate Matter (PM2.5) National Ambient Air Quality Standards (NAAQS)

Scientific and Technical Documents Supporting the 2012 Review of the PM Standards

Related Rules

Implementation of the National Ambient Air Quality Standards (NAAQS) for Fine Particulate Matter (PM2.5): State Implementation Plan (SIP) Requirements

2006 National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM2.5)

  • PM Home
  • Particulate Matter (PM) Basics
  • Health and Environmental Effects
  • Setting and Reviewing PM Standards
  • PM Standards Regulatory Actions
  • Implementing PM Standards
  • PM Implementation Regulatory Actions
  • SIP Checklist Guide
  • PM SIP Training Presentations
  • PM Data and SIP Status Reports
  • Other Criteria Air Pollutants
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 15, 2022
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