Natural Contamination in Radionuclide Detection Systems

Through the use of low-level gamma-ray spectrometry, clean material for construction of radionuclide detection systems has been identified. In general aluminum contains high quantities of 232Th and 238U with minimal quantities of 40K. Stainless steels contain 60Co. The radioactive contents of foams, cements, and light reflective materials are quite variable. Molecular sieve materials used in germanium spectrometers contain from 4-9 dpm/g. Only through a judicious choice of materials can a spectrometer with the lowest achievable background be assembled.