[en] In 1981, all the necessary radiation safety works were carried out in an attempt to minimize the unnecessary radiation exposure of personnel engaged in radiation working in the radiation field and also to prevent the radiation accidents. The operational radiation safety works consisted of the measurement of background radiation level in and around the nuclear facilities and laboratories, the radioactive contamination control, and the personnel radiation monitoring. The maximum background radiation level in controlled and uncontrolled areas in the year of 1981 ranged from 0.03 to 127 mR/hr, monthly average background radiation levels were between 0.02 and 2.18 mR/hr, and the annual background radiation level showed 0.35 mR/hr, which is a little higher than that of the last year. In personnel radiation monitoring for external exposure, there was no radiation worker who has received over the maximum permissible dose. The average annual external dose and the maximum annual dose to radiation workers were 177.7 mrem and 2436 mrem, respectively, and there were no significant internal exposures. (Author)