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  2. Air Quality Analysis

Exceptional Events Analysis and Visualization Tools

The following tools can help with data screening and determining regulatory significance in support of exceptional events demonstration submissions.

Identify days potentially impacted by exceptional events

  • Multi-year Tile Plot 
    Plots daily AQI values across multiple years. Each tile represents one day of the year and is color-coded based on the highest daily AQI value, helping identify days potentially impacted by exceptional events.
    Example of multiyear tile plot
  • Single-year Tile Plot
    Plots daily AQI values for a single year. Each tile represents one day of the year and is color-coded based on the highest daily AQI value, helping identify days potentially impacted by exceptional events.
    Example of a tile plot
  • Concentration Map
    Maps daily concentrations over several days which can help identify areas potentially impacted by exceptional events.
    Example of concentration map
  • AirNowTech Navigator (requires account on AirNowTech)
    AirNowTech is a password-protected website for air quality data management, analysis, and decision support. It allows users to:
    • Access monitoring site data, information, and polling status
    • Analyze current and past air quality events and episodes
    • Submit and analyze air quality forecasts
       

Assess potential regulatory significance

  • Exceptional Events Design Value Tool 
    This tool allows state, local, and tribal air monitoring agencies to determine the regulatory significance (i.e. whether excluding concentrations affected by exceptional events will affect attainment of the NAAQS) of ozone and PM2.5 concentrations impacted by exceptional events by calculating the impact of excluding these concentrations on the design value, the statistic used to determine whether an ambient air quality monitoring site is meeting the NAAQS.
  • Air Quality Statistics Report

Determine exceptional event tier category for your site(s) 

  • PM2.5 Tiering Tool 
    This tool displays daily PM2.5 concentrations, along with tier levels based on the methodology described in the PM2.5 Wildland Fire Exceptional Events Tiering Document.

Expedited Modeling of Burn Events Results (EMBER) 

  • EMBER Dataset Tool
    This tool displays ozone monitoring days that may have been impacted by fire emissions in the summer of 2023. 

Here are additional online resources and tools related to exceptional events data analysis.

Air Quality Analysis

  • NAAQS Review Analysis
    • Carbon Monoxide Analyses
    • Lead Analyses
    • Nitrogen Dioxide Analyses
    • Ozone Analyses
    • Particulate Matter Analyses
    • Sulfur Dioxide Analyses
  • Exceptional Events Analysis
    • Federal Register Notices
    • Example Demonstrations and Responses
    • Final 2016 Exceptional Events Rule
Contact Us About Air Quality Analysis
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on December 19, 2024
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