The Occupational Exposure of Radiation Workers (I)

Medical use of X-rays and radioisotopes are gradually increasing for diagnosis and therapy, and radiation workers, special doctors, nurses and radiological technicians, have many times of occupational exposure. The procedures for monitoring external exposure of personnel inclide the wearing of a filmbadge or a pocket chamber. The results of filmbadge monitoring in Yamaguchi University Hospitao for last 10 years were described in this paper. The results were as follows : (1) Total number of filmbadges that radiation workers have used during 2 weeks at radiolgical examination and therapy were 610 in 1964, which had ben increasing yearly, and wre 1999 in 1972. (2) Radiological technicians had generally low occupational exposure, and about 90 per cent of their filmbadges were exposed less than 10 mR. (3)　Approximately 65 per cent of filmbadges that nurses were less than 10 mR. But some nurses who higher exposure than 100 mR in radiological examination. (4) Some doctors sustained occupational exposure more than 150 mR. From these data, some problems on radiation monitoring using a filmbadge were discussed.