On-site calibration of stationary gamma dosimeter using energy response correction method

In order to solve the difficult problem of calibration for large range radiation detectors, an onsite calibration method for stationary gamma dosimeter was studied using X ray source. The energy response of both high energy and low energy regions for dosimeter which was the same type as the on-site instrument were tested in the laboratory, and the energy response curve of the dosimeter was obtained using Monte Carlo simulation. Then the substitution method was used for dosimeter calibration in the field, and the calibration coefficients were modified with the energy response curve. The results of comparison experiment have shown that the error between on-site calibration coefficient and laboratory calibration coefficient was less than 5%. This method can improve the measurement accuracy of stationary dosimeter, and it has great reference value for the radiation safety management and radiation environment evaluation. (authors)