Gamma spectrometry system is used to measure the activity of a radionuclide, based on the energy and intensity of the gamma radiation emitted from that radionuclide. Every gamma emitting radionuclide has it owns characteristic energy which can be used for its identification. The intensity at such energy enables the activity concentration of a radionuclide in a sample to be quantified. Among the radionuclides that can be measured using this system are Cs-134, Cs-137, Ra-226. Ra-228. K-40 and Am-241.