A FULLY AUTOMATED SECONDARY STANDARD X-RAY CALIBRATION FACILITY FOR PERSONAL DOSEMETERS

The individual monitoring service at the Helmholtz Zentrum München has extended the calibration facilities provided at the Munich IAEA/WHO secondary standard dosimetry laboratory with a new fully automated X-ray calibration facility for the calibration of personal dosemeters according to the ISO 4037 standard series. This work describes the X-ray irradiation system and the automated dosemeter transport system as well as the measurements performed to characterize the photon fields and to ascertain conformity to the ISO standard. Standard uncertainties of the radiation quantities provided by the system are given together with a discussion of some of the problems that are encountered in fulfilling the requirements of a matched field according to the latest drafts of the ISO 4037-1 standard.