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  2. Air: Fate, Exposure, and Risk Analysis (FERA)

Guide to Selected Algorithms, Distributions, and Databases Used in Exposure Models Developed By the Office of Air Quality Planning and Standards

This report and the appendices provide a detailed description of the components of the models pNEM, APEX, and HAPEM, at the time of the report, along with an explanation of the component's role within the source exposure model. 

  • Guide to Selected Algorithms, Distributions, and Databases Used in Exposure Models Developed By the Office of Air Quality Planning and Standards, May 2002 (pdf) (1.75 MB)
  • Appendices - Guide to Selected Algorithms, Distributions, and Databases Used in Exposure Models Developed By the Office of Air Quality Planning and Standards, June 2003 (pdf) (468.11 KB)

Air: Fate, Exposure, and Risk Analysis (FERA)

  • Total Risk Integrated Methodology (TRIM)
    • TRIM.FaTE
    • TRIM.Expo
    • TRIM.Risk
    • Peer Review and Publications
  • Multimedia Fate and Transport Modeling
    • TRIM.FaTE
    • Other Models and Related Information
  • Human Exposure Assessment and Modeling
    • Criteria Air Pollutant Exposure Assessment
    • Databases to Support Exposure Modeling
    • Air Pollutants Exposure Model (APEX/ TRIM.Expo Inhalation)
    • Hazardous Air Pollutant Exposure Model (HAPEM)
    • Other Models and Exposure-Related Information
  • Risk Assessment and Modeling
    • Air Toxics Risk Assessment
    • Criteria Air Pollutant Risk Assessment
    • Human Exposure Model (HEM)
    • EPA Risk Assessment Policy, Guidelines, and Related Materials
Contact Us about FERA
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 20, 2025
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