Personal safety issue is one of the major limitations in landmine detection by nuclear techniques. In this paper, the dose rate received by the operator of different hand-held landmine detection systems using the neutron backscattering method was investigated. Monte Carlo method was used to simulate a computational model of the body, instruments with different shielding configurations and soil with various moisture contents. The effective dose received by the different organs of the operator has been estimated by using two different approximation methods including average equivalent dose and dose equivalent assessment. The results obtained by these two methods were compared. The common results showed that the operator dose rate depends on the facility shielding, soil moisture level, and source-to-operator distance. Also, although the absorbed dose received by most organs generally decreases as a function of source to operator distance, for some organs such as kidneys and lungs it firstly increases when source-to-operator distance increases up to 0.7–1.2 m and after that the absorbed dose decreases. Furthermore, the results showed that the effective dose received by the operator has its maximum value when the source to operator distance is 0.60 m.

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