Practical considerations regarding high resolution gamma-spectrometry measurements of naturally occurring radioactive samples

High-resolution gamma-spectrometry provides fast, accurate, non-destructive isotopic analysis of natural radionuclides in environmental samples. Low energy HPGe detectors (30%) with resolution less than 2.0 keV at 1332 keV of 60Co and with linked analytical software, provide good peak-to-background performance and accurate unfolding of multiplet regions. A procedure regarding high-resolution gamma-spectrometry measurements of naturally occurring radioactive samples is presented here including calibration, background interference, self-absorption, practical considerations and validation with respect to IAEA reference materials. Recommended peaks for quantitative measurements, deriving from the analysis of observed spectral interferences as well as from radioactive equilibrium considerations, are reported.