The aim of this work was to start the development of a capability to evaluate gamma spectrometric measurements of a higher complexity for a high number of gamma emitting radionuclides present in a sample. Sources containing fission products at different times, 1-365 days, after fast fission of 235U were created. At these times spectra were generated with a high purity germanium detector (HPGe). Thereafter, evaluation of the spectra was tested using the software Gammavision, with a focus on receiving results from the gamma emitting radionuclides that contribute most to the radiation dose. Exposure from external radiation and internal radiation via food and inhalation were considered.