The Swedish Defence Research Agency (FOI) has on behalf of the Swedish Radiation Safety Authority (SSM), arranged a laboratory intercomparison using a certified reference material, for radiochemistry / radiometry laboratories at Swedish nuclear facilities. The intercomparison included measurements of seven radionuclides in a certified reference material having activities traceable to the International System of Units (SI). The analysis method was gamma spectrometry and eight laboratories participated with measurements on a total of 47 detector systems. In this report, the results from the laboratory intercomparison are reported.