Abstract: The methods of background subtraction for thermoluminescence (TLD) personal dose monitoring commonly used in nuclear power plants are presented. TLD monitoring in NPPs has the characteristics of a large number of measurements, a large number of uses, and a long time-consuming measurement/annealing. The current subtraction method commonly used ignores the background differences caused by the scale of measurements and differet annealing times, which have a great impact on the accuracy of monitoring results. In response to the above problems, we attempt to use the cumulative time background to perform subtraction, for each dosimeter's reading and annealing time, to eliminate the dose error caused by these differences, so as to improve the accuracy of personal dose monitoring of occupational external exposure in nuclear power plants.

Key words: Personal dose monitoring, TLD, Background subtraction