Three-dimensional (3D) reconstruction models are useful for many situations in decommissioning work at nuclear power plants (NPPs). In our previous study, we developed a scanning support system that enables users to construct 3D reconstruction models without missing even in very complicated environments such as those of NPPs. This study was conducted to evaluate the developed system: we compared the performance of the developed system and an existing scanning system. Results demonstrated that the developed system can scan larger areas and obtain useful images more steadily for constructing 3D reconstruction models. However, results also revealed the algorithm used to detect missing areas was slow and that the frame rate was low. As future work, the algorithms must be optimized to increase the frame rate.