Nuclear data including decay constants in RADTRAD.nix have been compared with those in ICRP-107. Inconsistencies were found through comparisons. Attached please find an Excel file containing the nuclides with the differences of decay constants greater than 0.1%. I also found different naming of radionuclides between RADTRAD and ICRP-107. For example, “Eu-150a” in RADTRAD should be “Eu-150m” in ICRP-107. The inconsistency in certain case might be misleading. For example, I believe “Nb-98” in RADTRAD.nix should be “Nb-98m” in ICRP-107. However, there is another “real" Nb-98. The decay constant of the real Nb-98 is about 1000 times larger than the Nb-98 (which should actually be Nb-98m) in RADTRAD!
A bit digging reveals that the data in RADTRAD.nix seems to be from ICRP-38. Since ICRP stated in its website that ICRP-38 has been superseded by the new publication ICRP-107. Is there a plan or timeline for RADTRAD/SNAP develper to transition to ICRP-107?
| Attachment | Size |
|---|---|
| decay constant comparisons between radtrad.nix and icrp-107 | 28.31 KB |
Modifying Nuclide Information
Hello Quan,
Currently, SNAP/RADTRAD only comes with ICRP-38 data as defaults. We will be updating SNAP to allow the user to select between ICRP-38 and ICRP-107 during the next major release of SNAP/RADTRAD (incorporating the Reg Guide 1.183 Rev 2 changes in the 2026 timeframe). The ability to use ICRP-38 data will be retained.
There is a way to modify the nuclide data manually to align more closely with ICRP-107. In the Nuclide Data tab, you can select "User Defined" for the Nuclide Model. Then, you can select the Edit button next to the Nuclides field (the red E with the arrow pointing to the top right corner). Here, you can edit the nuclide name, atomic mass, half-life, daughter nuclides, and branching fractions. You can additionally add nuclides to the list as well as remove them.
Please let us know if you have any further questions.
-Sam Edwards