Comparisons of the radiation protection standards for air kerma of the NIST and the BIPM for Co60 and Cs137 gamma radiation

Published

August 1, 2014

Author(s)

Ronaldo Minniti, C. Kessler, P J. Allisy-Roberts

Abstract

An indirect comparison of the standards for air kerma of the National Institute of Standards and Technology (NIST), USA, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the Co60 and Cs137 radiation protection-level beams of the BIPM in September 2011. The comparison results, based on the calibration coefficient for two transfer standards and expressed as a ratio of the NIST and the BIPM standards for air kerma, are 1.0023 with a combined standard uncertainty of 3.1 X 10–3 in Co60, and 0.9990 with a combined standard uncertainty of 3.2 X 10–3 in 137Cs. The result in the Co60 beam for radiation protection agrees within the uncertainties with the result of the comparison carried out at the same time in the CIS Bio Co60 beam for radiotherapy level air kerma.

Citation

Metrologia

Volume

51

Pub Type

Journals

Keywords

air kerma, BIPM, cesium 137, chamber, cobalt 60, comparison, gamma rays, protection

Citation

Minniti, R. , Kessler, C. and Allisy-Roberts, P. (2014), Comparisons of the radiation protection standards for air kerma of the NIST and the BIPM for Co60 and Cs137 gamma radiation, Metrologia (Accessed October 9, 2025)