An intercomparison of several environmental TLD systems

Three environmental dosemeter systems, Panasonic UD-200S, TI, and Panasonic UD-801A provided by two utilities, were evaluated. The absolute system calibrations and the system dependent variations in the derived doses were investigated by irradiating the dosemeters at three different exposure levels in a well characterised photon field (137Cs/137 Basup(m)) in the laboratory. The resulting TL response data were analysed using standard statistical methods. The UD-801A system results, while deviating the most from the delivered doses, exhibit markedly lower fluctuations than the others. This effect appears to be the result of using a stringent statistical selection criterion and determining individual element calibration factors according to the guidelines of Plato and Miklos. Also, the chi squared analysis indicates that the normal distribution model does not provide a highly accurate representation of the data. (author)