Standard X Ray Beams for Calibration of Dosemeters Used in Radiation Protection Practice

Abstract

Kerma in air is a widely used reference quantity specified by different calibration laboratories. Calibration of dosemeters used for individual and environmental monitoring requires a knowledge of conversion coefficients between the air kerma and an appropriate protection quantity. These were determined for sets of standard X ray beams using measured spectral distributions, calculated mean energies and effective energies obtained from HVLs measured by an ionisation chamber. There is a good agreement among these three approaches for energies down to 60-70 keV. For lower energies one can expect differences up to 10% it the coefficients are determined from the mean or effective energy instead from the spectral distribution