Comparison of the standards for absorbed dose to waterof the NPL, United Kingdom and the BIPM for 60Co γ rays

Abstract

A comparison of the standards for absorbed dose to water of the National Physical Laboratory (NPL), United Kingdom and of the Bureau International des Poids et Mesures (BIPM) has been made in 60Co gamma radiation under the auspices of the key comparison BIPM.RI(I)-K4. The comparison result, based on the calibration coefficients for two transfer standards and expressed as a ratio of the NPL and the BIPM standards for absorbed dose to water, is 0.9980 (0.0064). The degrees of equivalence for the NPL and the other participants in this comparison have been calculated and the results are given in the form of a table for the eleven national metrology institutes (NMIs) that have taken part in the ongoing comparison for absorbed dose to water. A graphical presentation is also given.Main text.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCRI Section I, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).