Evaluation of lead shielding for a gamma-spectroscopy system

Three types of lead shielding assemblies were investigated to establish which provides the lowest background as preliminary work for determining the efficiency of a High Purity Germanium (HPGe) detector. The background continuum and peaks were examined using gamma spectroscopy with a coaxial and a planar HPGe detector. The 210Pb concentration in each lead sample taken from the assemblies was quantitatively determined. A French lead sample was found to have the lowest background in this relative comparison with a 210Pb concentration of 29.1±1.3 Bq kg−1.