Some physico-technical aspects of the new generation of self-calibrated alanine/EPR dosimeter and results from the international intercomparison trial

Some physico-technical parameters of the self-calibrated alanine/EPR dosime ters are described. Principally, this new type of solid state/EPR dosimeter contains radiation sensitive diamagnetic material (in the present case, al anine), some quantity of EPR active, but radiation insensitive, substance ( for example. Mn2+/MgO) playing roles of an internal standard and a binding material. Thus with this dosimeter the EPR spectra of alanine and the inter nal standard Mn2+ are recorded simultaneously and the dose response is repr esented as a ratio of EPR signal intensities of alanine versus Mn2+ as a fu nction of absorbed dose. As a result, the data of the present study have sh own that there is practically no interference of dosimeter EPR response (ex pressed as the ratio I-alaine/I-Mn) from the way of preparation (homogeneit y), behavior after irradiation (fading of EPR signals with time, influence of different meteorological conditions) as well as specific spectrometer se tting conditions. These dosimeters show satisfactory reproducibility of pre paration and reading as well as stability on keeping. Thus, fulfilling the described physico-technical data of this type of dosimeters, the reproducib ility of the readings is significantly improved particularly when intercomp arison among different laboratories is performed. This conclusion is confir med by independent studies of the described self-calibrated alanine/EPR dos imeters in several laboratories in Europe. Results of which are also report ed.