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  2. Particulate Matter (PM) Pollution

Proposed Decision for the Reconsideration of the National Ambient Air Quality Standards for Particulate Matter (PM)

Announcement

February 7, 2024 - EPA strengthens air quality standards for fine particle pollution (PM2.5)

On January 6, 2023, after carefully reviewing the most recent available scientific evidence and technical information, and consulting with the Agency’s independent scientific advisors, EPA announced its proposed decision to revise the primary (health-based) annual PM2.5 standard from its current level of 12.0 µg/m3 to within the range of 9.0 to 10.0 µg/m3.  EPA also proposed not to change the current:

  • secondary (welfare-based) annual PM2.5 standard,
  • primary and secondary 24-hour PM2.5 standards, and
  • primary and secondary PM10 standards.

In addition, EPA proposed revisions to other key aspects related to the PM NAAQS, including revisions to the Air Quality Index (AQI) and monitoring requirements.


Read the proposed decision:  Notice of Proposed Rulemaking for the EPA Reconsideration of the National Ambient Air Quality Standards for Particulate Matter
 
Fact Sheets:
  • Primary and Secondary Standards for Fine Particle Pollution (PM2.5) and Coarse Particle Pollution (PM10)
  • Air Monitoring for Fine Particle Pollution (PM2.5)
  • Air Quality Designations and Implementation 
  • Wildland Fire, Air Quality, and Public Health Considerations (pdf) (120.39 KB)
 
Regulatory Impact Analysis 
 
Maps:
  • Current and Projected Air Quality Data for Counties with Monitors
 
Table:
  • Fine Particle Concentrations for Counties with Monitors Based on Air Quality Data 2019–2021
Presentation:
  • Proposed Revisions to PM NAAQS - Overview Presentation

 
 

Particulate Matter (PM) Pollution

  • 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 about Particulate Matter (PM) Pollution
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on January 30, 2025
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