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Radionuclide Standardization by Primary Methods: An Overview



Ronald Colle


Primary methods of radionuclidic standardization serve as the underlying basis of the physical measurement standards of activity that are needed in virtually every sub-discipline of radioanalytical and nuclear chemistry. Primary methods refer to the direct measurement of the number of nuclear transformations that occur per unit time, without recourse to other calibrations or standards. Such measurements, leading to the development and dissemination of radioactivity standards, are primarily performed under the purview of national metrology laboratories, like the National Institute of Standards and Technology (NIST) in the U.S.A. This paper briefly reviews some of the various primary methods that have been developed by many such laboratories over many years. Their features and their role in ensuring the quality of radioactivity measurements are highlighted by several primary standardizations that have been recently performed at NIST.
Journal of Radioanalytical and Nuclear Chemistry


primary standards, radioactivity measurements, radionuclide


Colle, R. (2009), Radionuclide Standardization by Primary Methods: An Overview, Journal of Radioanalytical and Nuclear Chemistry, [online], (Accessed February 22, 2024)
Created February 17, 2009, Updated February 17, 2017