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Secondary standards for 223Ra revised



Denis E. Bergeron, Jeffrey T. Cessna, Brian E. Zimmerman


Dose calibrator dial settings reported by NIST in 2010 (ARI v. 68, p. 1367) are now known to give erroneously low (by 10 %) activity readings. The original determinations were based on a chain of calibrations; a broken link in this chain was recently discovered. New calibration factors (i.e., dial settings), directly linked to NIST primary standards, are reported here. In addition, the raw data used to derive the factors reported in 2010 are revisited. The validity of the reevaluation is established via comparison with the new experiments and revised calibration factors for numerous clinical geometries are reported. The main conclusions of the 2010 report regarding geometry effects remain valid.
Applied Radiation and Isotopes


Ra-223, radium, alpha-emitter, dose calibrator, dose vial, syringe, radiopharmaceutical


Bergeron, D. , Cessna, J. and Zimmerman, B. (2015), Secondary standards for 223Ra revised, Applied Radiation and Isotopes, [online], (Accessed April 24, 2024)
Created March 5, 2015, Updated November 10, 2018