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Environmental Protection Agency Johnson-Ettinger model (J&E model) Overview  

The J&E Model is a one-dimensional analytical solution to convective and diffusive vapor transport into indoor spaces. It provides an estimated attenuation coefficient that relates the vapor concentration in the indoor space to the vapor concentration at the source of contamination. The model can simulate either a steady-state solution to vapor transport (constant source) or a quasi-steady-state solution (diminishing source). Inputs to the model include the chemical properties of the contaminant, the properties of the soil in the saturated and unsaturated zones, and the structural properties of the building.


Johnson-Ettinger model Home Site
  • Human Health Risk Assessment
  • Analytical Modeling
  • Input
  • Tabular File: NA
  • Graphical File: NA
  • Output
    • Tabular File: *.xls
    • Graphical File: NA
    • Print Report: Yes
    • Chlorinated Solvents
    • Petroleum
    • Soil Gas
    • Air
    Technical Team Members
    • Risk Assessor
    J&E Model - data loading
    • Data must be entered manually. Data are entered into a Microsoft Excel spreadsheet.
    • Some cells have pulldown menus so the user can toggle through the list of applicable fields, such as chemical compound and soil parameters.
    J&E Model - graphic loading
    • Not applicable.
    J&E Model - logical flow
    • Users enter data in the DataEntry worksheet.
    • Parameters are listed in the ChemProps worksheet.
    • Chemical properties of the selected compounds are listed in the ChemProps worksheet.
    • Results are calculated in the Compute worksheet.
    J&E Model - expert knowledge
    • An understanding of the site characteristics is necessary to select appropriate parameter values.
    • Expert knowledge is necessary to interpret results and understand parameters.
    J&E Model - documentation
    • The users manual is designed to lead users through data entry process by explaining the meaning and limits of each of the applicable fields.
    J&E Model - output
    • Results are displayed in Microsoft Excel format within the workbook's Compute worksheet.
    • Results can be saved as a Microsoft Excel workbook.
    J&E Model - sources
    • Version 3.0 downloaded November 19, 2004.
    Note that this DST matrix is under active construction. Comments and suggestions about the structure
    or content of this website should be sent to Mike Adam .
    This web site contains technology information from private contractors and government agencies and is for informational purposes only. EPA cannot guarantee the accuracy or completeness of the data. Reference to any specific commercial product, process, or service, by trade name, trademark, manufacturer, or otherwise, does not constitute or imply the endorsement, recommendation, or favor of the United States Government.