Historical
ISO 6980:1996
Reference beta radiations for calibrating dosemeters and dose-rate meters and for determining their response as a function of beta-radiation energy
This International Standard specifies the requirements for reference beta radiations produced by radionuciide sources to be used for the calibration of protection level dosimeters and dose-rate meters1), and for the determination of their response as a function of beta particle energy. It gives the characteristics of radionuclides which have been used to produce reference beta radiations, 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 7 mg.cm−2 in the ICRU sphere. The energy range involved lies between 66 keV2) and 3,6 MeV and the absorbed dose 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 absorbed dose rate as a function of the angle of incidence are given.
This International Standard proposes two series of reference beta radiations from which the radiation necessary for determining the characteristics (calibration and energy response) of an instrument should be selected.
Series 1 reference radiations are produced by radionuclide sources used with beam-flattening filters designed to give uniform dose rates over a large area at a specified distance. The proposed sources of 90Sr + 90Y, 204TI and 147Pm produce maximum dose rates of approximately 5 mSv. h−1.
Series 2 reference radiations are produced without the use of beam-flattening filters, which allows planar sources of large area and a range of source-to-calibration plane distances to be used. Close to the sources, only relatively small areas of uniform dose rate are produced, but this Series has the advantage of extending the energy and dose rate ranges beyond those of Series 1. The radionuclides used are those of Series 1 with the addition of the radionuclides 14C and 106Ru + 106Rh; these sources produce dose rates of up to 10 Sv.h−1.
1) These also include personal dosimeters.
Content Provider
International Organization for Standardization [iso]
