| Objective:Individual dose monitoring can detect accurately exposure doses of radiation workers. It is also an important part of work for prevention against excessive radiation damage. Abnormal individual doses were investigate in different occupation staffs,and to explore the frequency and the reasons of the abnormal individual doses . The research will provide reference data for establishment of standard about occupational exposure of radiation workers and the classified supervision of radiation safety.Methods:The individual doses of 1203 radiation workers were detected in some lab in Jiangsu province from 2008 to 2009. The individual doses were detected by optically stimulated luminescence,and the effective dose, equivalent dose of eye lens and equivalent dose of skin were analysed by the Chi-square test with the methods of frequency analysis, and p <0.05 was considered statistically significant.The reasons of abnormal individual doses were also discussedResults:The individual dose of majority subject investigated was less than 1 mSv, the dose of the occupational exposure was less than the natural background radiation, which had little effect on health. The people who worked in some workplace using the source classⅡandⅡclass-ray devices were relatively high individual dose in industry, there was some high dose in hospital and mining companies where had the source class I and III, and the people had low individual doses, who worked in the other workplace using the source class IV and V and III class-ray devicesCompared for the abnormal effective dose incidence of person in different industries, the rate of abnormal effective dose was higher in the wokplaces using the source classⅡthan in the other industy, the difference was statistically significant; and it was not obviously in different years.The reasons for high individual doses were next: personal dosimeters were not used standardized,which were placed in the work clothes in long-term; while the clothes were left in the workplace; even some dosimeter was placed in the side of the ray device;some radiation workers didn't change the dosimeter in time ;Some of radiation workers who used mobileγ-detector were lack of adequate knowledge about radioactivity protection.All of which led to the measured doses much higher than the national standard.Conclusion:The reasons of man-made were majority in all of the reasons that caused high doses. The people who worked in the workplace using source classⅡhad relatively high individual dose. |
