Radiation safety education/training is essential and is associated with a reduction in the radiation dose to both patients and staff. We used a questionnaire to assess the level of radiation safety knowledge among nurses working at Tohoku Kosei-Nenkin Hospital. Some nurses were also interviewed. The results of our study indicate that the nurses had insufficient radiation safety knowledge and that a high percentage of nurses were concerned about the health hazards of radiation. Moreover, more than 80% of the nurses expressed an interest in attending periodic radiation safety seminars. Appropriate radiation safety training is required to reduce nurse radiation doses, and an understanding of radiation safety can help to optimize the patient dose.