Comparison of the standards for air kerma of the LNE–LNHB and the BIPM for 137Cs gamma radiation

Abstract

A direct comparison of the standards for air kerma of the Laboratoire National de Métrologie et d'Essais–Laboratoire National Henri Becquerel (LNE–LNHB), France and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 137Cs radiation beam of the BIPM in November 2008. The result, expressed as a ratio of the LNE–LNHB and the BIPM standards for air kerma, is 0.9984 with a combined standard uncertainty of 2.6 × 10−3. The result of the earlier direct comparison in 137Cs γ rays, made in 1995, was 1.0019(30); taking into account the changes made to the BIPM standard and using the present correction factors for the LNE–LNHB standard, the 1995 result becomes 0.9989(26), which is in agreement with the present comparison result.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 (MRA).