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This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2025. This website is no longer updated and links to external websites and some internal pages may not work. More information »

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  1. Home
  2. Air Quality System (AQS)

Obtaining AQS Data

Air quality data is available from several places depending on what you need and your preferred format.  

Air quality data from the AQS system is consolidated at the AirData website. That site has pre-generated files of extracted AQS data at the annual, daily, and hourly level.  It also has several reports, graphs, and maps that you can generate based on specific selections.  These are available from the main AirData page.  It also has a API (REST query interface) that allows you to query AQS raw data. If you need AQI (Air Quality Index) information, you can get it from the daily files on the pre-generated files page, or use the AirData query daily data interface.

If you need real time data, go to the (AirNow Gateway / API page)


County AQI information

Air Quality System (AQS)

  • AQS User Support
    • New User Registration
    • Training
    • Events Calendar
    • Java Memo
  • All Manuals and Guides
    • User Guide
      • AQS at a Glance
      • ENSC at a Glance
      • Logging On
      • Site ID Format
      • Batch Submission - Overview
      • Batch Submission - Using the ENSC
      • Batch Submission - Loading Using AQS
      • Batch Submission - Type of Data
      • Correct - Overview
      • Correct - Raw Data
      • Correct - 1-PT QC
      • Maintain - Overview
      • Maintain - Site
      • Maintain - Monitor
      • Maintain - Adding Events
      • Maintain - QA
      • Setting Up Samplers
      • Data Reports
      • CA Dump Bucket
      • Logging Off and Additional Info
    • Code Lists
    • Data Dictionary
    • Data Coding Manual
    • AQS Primer
    • Frequent Questions
  • Related Resources
    • Monitoring and Policy Memos
    • AQS Pollutant Memos
    • Quality Assurance and Audits Memos
  • Archive Data
  • Obtaining AQS Data
    • API
    • About AQS Datamart
    • Pre-Generated Data
AQS Contact Us
AQS Contact Us to ask a question, provide feedback, or report a problem.
Last updated on January 7, 2025
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