International intercomparison of solid state dosemeters within environmental monitoring

An international intercomparison study was carried out to optimise the readout procedures of the dosimetry systems used in the corresponding national environmental dosimetry laboratories. The intercomparison was based on the joint cross-calibration in the laboratories involved and an exchange of dosemeters within the respective national environment monitoring programmes. The aims of the study were the intercomparison of field irradiations at three exposure sites in each of the three participating countries, the determination of the actual field fading correction factor and the contribution of (national and international) transit doses. Six dosimetry systems have been employed in five measurement cycles using thermoluminescent LiF:Mg,Ti, CaF 2 :Mn, and CaSO 4 :Dy, as well as photoluminescent flat glass dosemeters. Within the uncertainty of measurement the results indicate no seasonal influence on the natural background level at any location, as well as no improvement in results by using fading corrections.