CIPM MRA COMPARISON REPORTS
PILOT STUDY
CCRI(I)-P12
Abstract
A comparison of therapy-level electron beam absorbed dose to water standards was carried out using alanine as the transfer dosimeter. Participants were LNHB, France, KRISS, Korea and NRC, Canada with the BIPM providing reference Co-60 irradiations to realize a Key Comparison Reference Value (KCRV) in the absence of a BIPM primary standard for electron beams. The alanine system used was that of the NRC, and steps were taken to completely separate the alanine read-out from the alanine irradiations at NRC, to ensure independence of the two steps. Irradiations were carried out in 2023 and final data was received in 2024.
All three participants agreed with the KCRV within 1.1 parts in 102, with combined standard uncertainties in the range 0.9 to 1.6 parts in 102.
The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).