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  2. Air Quality System (AQS)
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Frequent Questions

View frequently asked questions and answers related the the Air Quality System.

  • How do I close a monitor?
  • What do I do if I get a Post Fatal Error or Load Active Error?
  • What do I do if I get the message: "A pre-production record already exists for the Monitor - Date - Time"?
  • How do I reactivate monitoring at a site?
  • What does "Unique Constraint Error" mean?
  • How do I create a new primary monitor at a site where PM2.5 monitoring has a QA collocated monitor?
  • How do I use the required frequencies settings?
  • How is NPAP Audit Data loaded / reviewed / approved?
  • Why do my data show up on the AMP251 but not the AMP256 report?
  • What do I do if I want the design value to be calculated using a primary and composite primary sampler?
  • When exactly does it matter what information has been added to the Maintain -> Site -> Primary Monitor Periods screen?
  • How long are batch form reports available for?
  • What are the different data statuses in AQS?
  • What is the difference between Agency and Screening Group?
  • What are the security access rule differences between Agency and Screening Group?
  • How do I delete a lot of Tribal data?
  • After an agency adds certification request flags, is the agency allowed to make changes to that year's raw data records?
  • Do you have to recertify data if it is null coded after you have certified the data?
  • How does AQS determine if a monitor is regulatory or not?
  • How do I allow a user to load QA data?
  • How do I close a QA Collocated monitor?
  • What do I do when I receive the error "Sample duration cannot change within a calendar year"?

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 28, 2025
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