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  1. Home
  2. Air Quality System (AQS)

AQS Related Resources

AIRData access to annual summaries of air pollution data.

AIRNOW is the EPA site with current Air Quality Index (AQI) levels indicating how clean the air is and whether it will affect your health.

CDX (Central Data Exchange) is the EPA's electronic reporting site.

State and Local Air/Environmental Agencies links to regional, state and local agency pages.

AMTIC (Ambient Monitoring Technology Information Center) contains information and files on ambient air quality monitoring programs, details on monitoring methods, relevant documents and articles, information on air quality trends and nonattainment areas, and federal regulations related to ambient air quality monitoring.

CHIEF (Clearinghouse for Inventories and Emissions Factors) is the EPA site that includes the NEI (National Emissions Inventory) database. The NEI replaces AFS as the EPA's repository of air emissions information for facilities, area, and mobile sources.


The following links are pointers to other hosts and locations on the Internet. This information is provided as a service. However, the U.S. Environmental Protection Agency does not endorse, approve or otherwise support the non-EPA sites.

Exchange Network for AQS data exchange (Node to node)

ECOS (Environmental Council of the States)

NACAA (National Association of Clean Air Agencies, formerly STAPPA/ALAPCO; State and Territorial Air Pollution Program Administrators / Association of Local Air Pollution Control Officials)

IMPROVE (National Park Service visibility data, operated by Colorado State University)

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
    • AQS 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
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 1, 2025
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