An experimental study of efficiency loss due to counting rate was performed to obtain a mathematical function of efficiency loss factor and the dead time of the detector. The construction of homogeneous packages has been carried out under 2 headings: full scale packages and mock up scale packages. To quantify heterogeneous packages a study of the best counting methodology was carried out. 2 systems have been tested: movable and static counting. A counting method to obtain a practically constant efficiency for any position in the drum, any length, surface size or shape of the radioactive material for the quantification of heterogeneous packages is described. Heterogeneous packages with an interior concrete shield have been studied considering them as an extension of the case of the aforementioned packages using correction factors fortransformation of the results of heterogeneous matrices into this kind of package. Calculation codes have been implemented to automate the necessary calculations for the quantification of every package studied. Program descriptions and flow diagrams are included.
A non-destructive method based on gamma spectrometry was investigated as a means of providing information on the radiological characteristics of low and medium level radioactive waste already packaged in drums. Various forms of full scale and mock up scale homogeneous packages, and heterogeneous packages simulating the random distribution of radioactivity which occurs in practice were used. Counting methods which provide a practically constant efficiency for any position in the drum and for any length, surface size, or shape of the radioactive material were evaluated. Calculation codes were also studied.