A simple method for estimating dose uncertainty in ESR/alanine dosimetry

ESR/alanine dosimetry is widely used as a reference, transfer and routine standard dosimetry system. In order to use it as a reliable standard, or in every situation where a high degree of accuracy is needed, the calculation of the absolute dose uncertainty is required. Even though general guides for estimating dose uncertainties are available, the actual calculation may be rather complicated. In this paper, an analytical expression for the dose uncertainty for the ESR/alanine dosimetry system is presented, and shown to be rather simple to use. The treatment is valid for doses below ca. 103 Gy. An alternative procedure should be followed if the calibration dose uncertainties are very varying, e.g. when the calibration dose range is wide. This procedure, the so-called effective variance method [Orear, J. (1982) Am. J. Phys. 50, 912], is described. Both methods are supplied with one numerical example. Suggestions on obtaining calibration curve parameters and their uncertainties, are emphasized.