It has been proven that landmine detection systems based on prompt gamma neutron activation analysis method can be used effectively in detecting low metal content mines. Unfortunately, neutron and gamma radiations of these systems are inevitable. Therefore, the personnel safety of these devices is one of the major limitations in using these systems. In this work, a system composed of a moderated americium- beryllium neutron source was considered. We have investigated different thicknesses of proper neutron shielding materials such as polyethylene and boric acid around the system to shield neutrons and increase the safety conditions for the operators. The effect of using different thicknesses of a cylindrical lead shield (around the source) for shielding the gamma radiation of the source was also studied. Several experiments were done to measure neutron and gamma dose equivalent rate at different distances from the source. Most of the results were compared with the results obtained by Monte Carlo N-particle transport 4C code. Finally, we found a system that is safe for the operators who work at about a 1 m distance from the landmine detection system.

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