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Radiation Protection

CAP-88 PC Version 4.1 Downloads and Supporting Documents

The CAP-88 (Clean Air Act Assessment Package - 1988) computer model is a set of computer programs, databases and associated utility programs for estimating dose and risk Helprisk Probability that an animal or individual exhibits a particular adverse effect for a specified exposure, expressed on a probability scale of 0 to 1. May be expressed as the proportion of a population effected and often converted to the percent effected. from radionuclide Helpradionuclide Any man-made or natural element which emits radiation in the form of alpha or beta particles, or as gamma rays. emissions to air. CAP-88 is a regulatory compliance tool under the National Emissions Standard for Hazardous Air Pollutants (NESHAP).   Version 4.1 is the most recent version of the code and may be used to demonstrate compliance with NESHAP Subpart H.  See the Notice of Availability for CAP-88 PC Version 4.1 from the Federal Register, March 5, 2020.

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The STARGET utility converts meteorological data in STAR format to a *.wnd file for use in CAP-88 PC Version 4.1.  A beta version of the STARGET utility is available for download.

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  • Download CAP-88 PC Version 4.1(42 MB, January 2020)
    IMPORTANT NOTE TO USERS: Installing Version 4.1 on your computer will uninstall Version 4.0. If you wish to use Version 4.0 for the current compliance cycle, please wait to install Version 4.1 until you have submitted your reports. If you have previously installed the beta version of Version 4.1, please uninstall it before downloading CAP-88 PC Version 4.1. To uninstall, open “Control Panel," click on “Programs and Features,” highlight the CAP88-PC Version 4.1 beta program, then right-click and select “uninstall.”
  • Download STARGET Utility (beta)(697 K, November 2019)

Supporting Documentation

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You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.
  • CAP-88 PC v. 4.1 Installation Notes (PDF)(3 pp, 326 K, Nov. 2019)
    A "readme" file with installation notes on CAP-88 PC Version 4.1
  • CAP-88 PC v.4.1 Quick Start Guide (PDF)(4 pp, 346 K, November 2019)
    This Quick Start guide provides basic installation and operating procedures for users who have a general knowledge of air dispersion compliance codes.
  • CAP-88 PC v. 4.1 Sample Datasets and Reports (PDF)(192 pp, 888 K)
    This report provides specific test case runs to show Version 4.1 properly generates results that agree with independent calculations for air concentrations and ground deposition rates. It includes the “Modtest” run on historical data from the Portsmouth, Ohio site which has been previously been used for model verification.
  • CAP88-PC v.4.1 Testing Report (draft) (PDF)(353 pp, 2 MB, January 2020)
    This testing report for CAP88-PC Version 4.1 includes a description of the six test cases used to test the incorporation of age-specific dose factors and lifetime risk factors; a description of the seventh test case that verified that calculation of air concentrations and working levels for radon only runs; a brief biographical sketch describing the independence and qualifications of the independent tester; and the conclusions drawn from the testing.
  • CAP88-PC v. 4.1 User Guide (PDF)(103 pp, 3 MB)
    User Guide for CAP-88 PC Version 4.1
  • STARGET File Converter Basic Instructions (PDF)(2 pp, 218 K)
    Instructions for the STARGET utility that converts STAR meteorological files to *.wnd files for use in CAP-88 PC Version 4.1.