The quality control in the production of spiked reference materials for gamma-ray spectrometry

Following a EUROMET project for the development of a range of spiked reference materials for gamma-ray spectrometry, a number of new techniques were adopted at ENEA for the routine production of these materials. A quality control of the produced samples was simultaneously started. It is based on HPGe gamma-ray spectrometry of the different samples in Marinelli beaker measuring geometry. Within a few years a great number of materials, with density values ranging from 0.4 to 1.8 g cm−3 and different chemical composition, spiked with mixtures of gamma emitters (60 to 1836 keV), were processed. The full-energy-peak efficiency values for the different matrices were normalised to a reference sample composition allowing the reduction of the acceptability criteria on which the quality control is based. Two theoretical models were used to compute the self-attenuation corrections obtaining a satisfactory agreement in the considered range of sample parameters.