ISO 6980-2:2022

This document specifies methods for the measurement of the absorbed-dose rate in a tissue-equivalent slab phantom in the ISO6980 reference beta-particle radiation fields. The energy range of the beta-particle-emitting isotopes covered by these reference radiations is 0,22MeV to 3,6MeV maximum beta energy corresponding to 0,06MeV to 1,1MeV mean beta energy. Radiation energies outside this range are beyond the scope of this document. While measurements in a reference geometry (depth of 0,07mm or 3mm at perpendicular incidence in a tissue‑equivalent slab phantom) with an extrapolation chamber used as primary standard are dealt with in detail, the use of other measurement systems and measurements in other geometries are also described, although in less detail. However, as noted in ICRU56^[5], the ambient dose equivalent, H*(10), used for area monitoring, and the personal dose equivalent, H_p(10), as used for individual monitoring, of strongly penetrating radiation, are not appropriate quantities for any beta radiation, even that which penetrates 10mm of tissue (E_max>2MeV).

This document is intended for those organizations wishing to establish primary dosimetry capabilities for beta particles and serves as a guide to the performance of dosimetry with an extrapolation chamber used as primary standard for beta‑particle dosimetry in other fields. Guidance is also provided on the statement of measurement uncertainties.