Quantitative estimations of the efficiency of stabilization and lowering of background in gamma-spectrometry of environment samples

Gamma-spectrometric complex of IEP of the NAS of Ukraine (as made in 1989) is considered, in which a passive multilayer external protection is used. A system of stabilization and reduction of background in the gamma-spectrometric complex was developed and investigated. The protection efficiency factors are considered as metrological coefficients, the calculation and analysis of which shows that their values differ at various energies of gamma-quanta and for different gamma-active nuclides.