Individual doses of radiation workers in Baoshan District of Shanghai from 2010 to 2013

Objective To understand the individual dose levels of radiation workers in Baoshan District of Shanghai,and to provide scientific evidences for developing radiation protection in the district. Methods The thermoluminescence dosimetry was used to measure the individual dose level of radiation workers according to the national and Shanghai regulations on radiological health protection. The data was analyzed to describe the variation of exposure levels. Results From 2010 to 2013,a total of 3 291 records were collected and 49 records were reported to be abnormal. The follow-up investigation showed that 44 abnormal records were due to artificial intention and 5 cases had really high exposure. The mean annual dose equivalent was 0.76 mSv/a and annual dose of 98.45% radiation workers was less than 5 mSv. The radiation worker in the enterprises had a highest mean annual dose equivalent(0.82 mSv/a),compared with that of staff in governmental hospitals (0.73 mSv/a), or staff in private hospital (0.31 mSv/a). The abnormal rates of individual dose declined year by year from 2010 to 2013 (χ² _trend=16.14,P<0.01). Conclusion Though the individual dose levels of most radiation workers in Baoshan District were low, there were still a few cases with higher levels. The supervision should be enforced.