ABSTRACT
Objective Radiation safety of emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor is studied, the radiation protection method of emergency repair personnel in the reactor cabin is described, which provides a theoretical reference for personnel radiation protection and emergency repair time control. Methods The radiation was simulated by the Monte Carlo method for emergency repair personnel in the reactor cabin under the natural circulation condition of the reactor, and the radiation was also analyzed with the radiation data measured by experiments in the reactor cabin under the natural circulation condition of the reactor. Results The neutron dose of external irradiation about reactor simulated computation was 140 μSv/h, and gamma radiation dose rate was 48 μSv/h. By experiment and calculation, the effective dose received by emergency repair personnel in the 30-minutein the reactor cabin was 2.2 mSv. Conclusions Under the natural circulation condition of the reactor, the gamma radiation is harmful to emergency repair personnel, but the focus of protection is different locations for maintenance. It's safe for emergency personnel to repair the reactor in 30 minutes in turn, wearing the respirators.