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  1. Home
  2. Outdoor Air Quality Data

Frequent Questions about AirData

View frequently asked questions about AirData by topic.

On this page:
  • Data Access
  • Data Availability
  • Data Summaries
  • AQI
  • Monitors  & Sensors
  • Data Fields
  • Reporting an Air Quality Problem

Data Access

  • What is the best way to access outdoor air monitoring data?

  • How do I cite data and graphics obtained from the AirData website?

  • Do I need to request permission to use the monitoring data and graphics from the AirData website in my research or publication?

Data Availability

  • Do you have outdoor air monitoring data for all counties in the U.S.?

  • Why do the outdoor air monitoring data summaries only go back to 1980? Isn’t older data available?

  • Why isn’t recent outdoor air monitoring data available? Where can I find that?

  • When will outdoor air monitoring data for the entire year be available?

  • Why isn’t there an outdoor air monitor in my county?

Data Summaries

  • Are monthly aggregates available for outdoor air monitoring data?

  • Do you provide outdoor air monitoring data aggregated at the state level?

  • Do you provide rankings of cities or states based on air quality?

  • Why do you use the highest summary statistic (AQI/concentration) among all monitors in an area to represent that area (as opposed to using an average)?

AQI

  • How is the AQI calculated?

  • Do all AQI plots use the most current AQI breakpoints - regardless of which year you request?

Monitors & Sensors

  • Who decides where monitors get placed?

  • Can I include my monitor in the EPA’s monitoring network?

Data Fields

  • What is an exceptional event?

  • What does the POC number refer to?

  • Does the ‘exclude exceptional events’ option exclude only EPA regionally-concurred exceptional events or all flagged events?

  • What is the difference between parameter codes 88101 and 88502 for PM2.5 monitors?

Reporting an Air Quality Problem

  • How do I report an air quality problem?

Outdoor Air Quality Data

  • Frequent Questions about AirData
  • Learn about Air Data
  • Interactive Map
  • Pre-generated Data Files
  • Download Daily Data
  • Download Raw Data (API)
  • Air Quality Index Report
  • Air Quality Statistics Report
  • Monitor Values Report
  • Monitor Values Report - Hazardous Air Pollutants
  • Air Quality Index Daily Values Report
  • Daily Air Quality Tracker
  • Tile Plot - Multiyear
  • Tile Plot - Single Year
  • AQI Plot
  • Concentration Plot
  • Ozone Exceedances
  • Concentration Map
  • PM2.5 Continuous Monitor Comparability Assessments
  • PM10 Continuous Monitor Comparability Assessments
  • Single Point Precision & Bias Report
Contact Us about Outdoor Air Quality Data
Contact Us about Outdoor Air Quality Data to ask a question, provide feedback, or report a problem.
Last updated on August 16, 2024
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