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

Consolidated Human Activity Database (CHAD)

The CHAD database includes nearly 180,000 individual study days of detailed human behavior, with each day broken down into individual hours and activity types. The data include demographic information such as age, sex, employment, and education level, which allows researchers to examine specific groups within the general population and how their unique behavior patterns influence their exposures to chemicals.

The data in CHAD can help researchers understand the patterns of human behavior that influence their exposure to chemicals in their environment. In addition, data from CHAD are routinely used by EPA and other government agencies, academia, and private organizations for human exposure and health studies, and in models used for exposure and risk assessment.

2019-2020 Version of CHAD

  • CHAD Master (CSV) (zip)
  • Chad Master (SAS) (zip)
  • CHAD-Master Documentation and User's Guide (4 MB)

Previous versions of CHAD

Technical Contacts:

John Langstaff (langstaff.john@epa.gov)

Stephen Graham (graham.stephen@epa.gov)

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 December 13, 2024
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