Analysis on external exposure dose level of radiotherapy and nuclear medicine workers in Guangdong province,2003-2012

Objective To analyze occupational external exposure dose of radiotherapy and nuclear medicine workers in Guangdong province from 2003 to 2012. Methods Personal doses of the radiological workers were monitored with thermoluminescence dose measurement and the data were analyzed. Results Totally 5 420 persons were monitored in this 10-year-long period. The rate of individual exposure dose exceeding 5. 00 m Sv / a was 99. 87%( 5 413 /5 420). The per capita annual effective dose was( 0. 52 ± 0. 11) m Sv / a,and it showed linear decrease tendency with increasing year over the 10-year-long period( P 0. 05). The actual measurement of annual collective effective dose was 2. 80 person·Sv. The distribution ratio of annual individual effective dose exceeding 5. 00 m Sv was 0. 001,while the distribution ratio of collective dose was 0. 028. Per capita annual effective dose in radiotherapy department was( 0. 44 ± 0. 09) m Sv / a,annual collective effective dose was 2. 00 person·Sv,accounting for 71. 43% of the collective effective dose. Per capita annual effective dose in nuclear medicine department was( 0. 86 ± 0. 17) m Sv / a,annual collective effective dose was 0. 80 person·Sv,accounting for 28. 57% of the collective effective dose. Per capita annual effective dose in nuclear medicine department was higher than that in radiotherapy department( P 0. 05). Conclusion The exposure dose of radiotherapy and nuclear medicine workers in Guangdong province was overall satisfactory,some workers should pay attention to strengthen their protection consciousness.