NF ISO 6980-2, M60-515-2 (12/2023)

This document specifies methods for measuring the absorbed dose rate in a plate phantom of tissue equivalent material in the reference beta radiation fields covered in the ISO 6980 series. The energy range of beta particle emitting isotopes covered by these reference radiations are between 0.22 MeV and 3.6 MeV in maximum beta energy, or 0.07 MeV to 1.2 MeV in average beta energy. Radiation energies outside this range are outside the scope of this document. While measurements in a reference geometry (0.07 mm or 3 mm depth at perpendicular incidence in a tissue-equivalent plate phantom) with an extrapolation chamber as primary standard are discussed in detail, the The use of other measuring systems and carrying out measurements in other geometries are also described, but in less detail. However, as ICRU report 56 (International Commission on Radiation Units and Measurements) points out, the ambient dose equivalent, H*(10), and the individual dose equivalent, Hp(10), used respectively for area monitoring and for individual monitoring in the case of highly penetrating radiation are not appropriate quantities for beta radiation, even for radiation capable of passing through a tissue thickness of 10 mm (Emax > 2 MeV). This document is intended for organizations wishing to develop skills in primary beta particle dosimetry and provides a guide to extrapolation chamber dosimetry as a primary standard for application to beta particle dosimetry in other areas. Recommendations for expressing measurement uncertainties are also provided.
(Automatic translation from French)