Environment

Air Quality Progress Dashboard

The metropolitan Washington region has made tremendous progress in its air quality thanks to more than a decade of actions at the federal, state, and local government levels. To learn more, click through the dashboard slides below and download the Air Quality Trends Report.

2024 - Daily Air Quality Index

2024 - Daily Air Quality Index

This chart shows the Air Quality Index (AQI) of each day during 2024. Conditions on the index include Code Green (good), Code Yellow (moderate), Code Orange (unhealthy for sensitive groups), Code Red (unhealthy), and Code Purple (very unhealthy).

* 2024 data is preliminary as of August 31, 2024.

Improving the Region's Air

All six pollutants regulated by the Clean Air Act have shown a downward trend in the region, and all but one pollutant, ground-level ozone, meet federal health-based air quality standards. Federal, state, and local measures that have improved the region's air quality, include:  

  • Acid Rain program (Phase 1 -1996/Phase 2 -2000,
  • Tier 2/3 (2004/2017)
  • Heavy-Duty Diesel Vehicle rule (2004/2007)
  • NOx SIP Call (2004)
  • Clean Air Interstate Rule (CAIR)/Cross-State Air Pollution Rule (CSAPR)/CSAPR Update (2009/2015/2017)
  • District of Columbia, Maryland, and Virginia’s Vehicle Inspection & Maintenance programs
  • Local gas can replacement program
  • Local renewable energy & energy efficiency programs

For additional information about air pollution and its impact, visit the Air Quality and Your Health page

For draft air quality data from this year, visit the Air Quality Data page.