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Radiation Protection

Federal Guidance Report No. 15: External Exposure to Radionuclides in Air, Water and Soil

Federal Guidance Report No. 15 (FGR 15), External Exposure to Radionuclides in Air, Water and Soil, tabulates age-specific reference person effective dose rate coefficients for 1,252 radionuclides based on external exposure to radionuclides distributed in air, water or soil.

FGR 15 updates and expands the 1993 Federal Guidance Report No. 12 (FGR 12), External Exposure to Radionuclides in Air, Water, and Soil. Compared to FGR 12, FGR 15 incorporates six different age groups (whereas FGR 12 had one), updated tissue weighting factors (as recommended in ICRP Publication 103) and radionuclide decay data (as provided in ICRP Publication 107), and improved computing power to provide more precise calculations.

A previous version of this report (EPA 402-R-18-001) contained errors in the dose coefficient tables. The revised report with corrected tables is available for download below; the previous version should be discarded.

NOTE: The FGR15_Setup.EXE file below must be opened in Windows and should NOT be installed in the Programs Files folder. It can be installed in any other folder on the disk, e.g., C:\My Programs\FGR15 or C:\EPA\FGR15.

The FGR15_Setup.EXE file below includes the FGR 15 Viewer, an application which enables the user to quickly find dose coefficients for specific radionuclides. More information about how to use the FGR 15 Viewer can be found in the accompanying README file.

The download also includes the following data tables as ASCII text files:

  • Reference person effective dose rate coefficients for each exposure scenario
  • Reference person tissue equivalent dose coefficients for each exposure scenario and age
  • Equivalent dose rate coefficients for monoenergetic photons

The ASCII text files are located in the “Supplemental” folder. These files can be opened with a text editor such as Notepad, Notepad++ or emacs.

Version 4.2 of the FGR 15 Viewer program, compiled in December 2020, replaces the earlier version published in August 2019. This updated version corrects an error in the earlier version that incorrectly indicated that the dose coefficients for praseodymium-142 (Pr-142) and uranium-235 (U-235) were zero. The updated version provides the correct non-zero dose coefficients for both radionuclides.

FGR15 Viewer Setup(6 MB, January 2021)

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