We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

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page title goes here Risk Assessment

CPM What's New

CPM Conversion

The What's New section keeps users informed of changes. Please check this site frequently to be advised of any recent changes.

August 2026

  • For the first decay method (peak output option), the peak time period options found in the other calculators have been added.
  • The site-specific input pages have been combined into a single page.
  • Calculations can now be done in Becquerels.
  • The GDR calculations for the peak output option have been reprogrammed for speed and replacement of fractional activity with unit activity files of the progeny.

December 2025

  • Website open to general public.

April 2024

  • Website open as a Beta release.