1 Scope
This document specifies the requirements for reference beta radiation fields produced
by radioactive sources to be used for the calibration of personal and area dosemeters
and dose-rate meters to be used for the determination of the quantities H p (0,07), H' (0,07; Ω ), H p (3) and H' (3; Ω ), and for the determination of their response as a function of beta particle energy
and angle of incidence. The basic quantity in beta dosimetry is the absorbed-dose
rate in a tissue-equivalent slab phantom. This document gives the characteristics
of radionuclides that have been used to produce reference beta radiation fields, gives
examples of suitable source constructions and describes methods for the measurement
of the residual maximum beta particle energy and the dose equivalent rate at a depth
of 0,07 mm in the International Commission on Radiation Units and Measurements (ICRU)
sphere. The energy range involved lies between 0,22 and 3,6 MeV maximum beta energy corresponding to 0,06 MeV to 1,1 MeV mean beta energy and the dose equivalent rates are in the range from about 10 µSv·h –1 to at least 10 Sv·h –1 . In addition, for some sources, variations of the dose equivalent rate as a function
of the angle of incidence are given. However, as noted in ICRU Report 56 [ 3 ] , 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 10 mm of
tissue ( E max > 2 MeV).