The operator training simulator has been started to develop for the purpose of safety and stable operation in the Rokkasho reprocessing plant, the first commercial spent nuclear fuel reprocessing plant in Japan. At present, the safety training simulator, which had been developed for the purpose of the specified abnormal events training, has already been in operation. The simulator was designed to contribute to the acquisition of the knowledge and skills indispensable for the plant operators and to the promotion of good team-work among operators. It was also designed in consideration of the simple and consistent extensibility to the full-scope training simulator which is now planned to develop using the same hard-ware. The model building and maintenance tools were applied as trial for the model tuning and modification. They must be indispensable for the reflection of the plant operation data and for the planning full-scope training simulator development. The usefulness and the validity of the simulator were ascertained through the training and its reports as the simulator development successfulness.
