Decay data for use in internal and external dose assessment are presented. Decay data for more than 800 radionuclides were taken from the Brookhaven National Laboratory database and formatted for use in internal or external dose assessment (giving nuclide half-life, decay types, energies, and abundances). Data are provided in both a Microsoft Word document and Excel spreadsheet, both of which are too large for publication in a journal. The technical basis for the data are given here, and the data are available via electronic transfer from a web site. These recently extracted data provide an update on previously published decay data values in a form readily accessible by many users worldwide.