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@#Abstract: Objective To retrospectively analyze the individual dose monitoring of radiation workers in Chongqing City from 2016 to 2020, so as to provide scientific reference for occupational health monitoring and radiation protection. Methods Radiation workers who performed individual dose monitoring in Chongqing Center for Disease Control and Prevention from 2016 to 2020 were selected as the research objects, and the monitoring data were collected and analyzed. Results A total of 40 926 individuals were included in this study, with a total of 135 622 person-years. The average annual individual effective dose of radiation workers over the five-year period was 0.56 mSv. NR1 and NR5, the ratio of the number of works receiving annual individual does exceeding 1 and 5 mSv to the to the total monitor workers were 13.019% and 0.335%. The annual effective dose per capita in Chongqing City showed a trend of first decreasing, then increasing and then decreasing again over the study period, with significant differences between different years (F=971.754, P<0.001). Although there were some differences in the variation trend of annual effective dose among different occupational categories, the overall trend was decreasing year by year. The average annual effective dose of nuclear medicine and interventional radiology was relatively high, and the difference was not statistically significant (P>0.05). The average annual effective dose of industrial flaw detection and accelerator operator in industrial application was relatively higher, and the difference was not statistically significant (P>0.05). There were statistically significant differences in the per capita effective doses of different occupational categories of medical application in different years (F=8.892-682.852, P<0.001). Among them, the per capita annual effective doses of five occupational categories of medical application were the highest in 2016, and the per capita annual effective doses of interventional radiology were the highest in 2018 and 2019. Conclusions The per capita annual effective dose of radiation staff in Chongqing has decreased year by year from 2016 to 2020, and remained at a relatively low level that meets national standards. The monitoring results suggest that the radiation staff of nuclear medicine, interventional radiology, industrial non-destructive testing and accelerator operator should give special attention to protect their occupational health and safety.
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ObjectiveTo determine the individual dose level and changing trend in the occupational external exposure of radiation workers in Shanghai， and provide scientific evidence for health risk assessment for radiation workers. MethodsIn the Occupational Health Management System for Radiation Workers of the National Health Commission-External Exposure Personal Monitoring and Management Subsystem， we retrieved the monitoring data of 38 077 external exposure individual dose of all medical radiation workers in Shanghai from 2015 to 2019. Using clustered sampling method， a total of 11 370 radiation workers in medical institutions （including tertiary， secondary， and primary hospitals） were selected in the study. Statistical analyses were conducted using SPSS 22.0. ResultsThe collective annual effective dose of 11 370 radiation workers was determined to be 4.340 person Sv， including 2.270 man·mSv in diagnostic radiology， 1.112 man·mSv in interventional radiology， and <0.5 man·mSv in other categories. The average annual effective dose was 0.382 mSv， which was 0.482 mSv in nuclear medicine， 0.431 mSv in radiotherapy， and <0.5 mSv in other categories. Moreover， the average annual effective dose of 6 workers （0.05%） was higher than 5 mSv， whereas that of 10 453 workers （92%） were less than 1 mSv； in addition， the annual dose of 911 workers （8.0%） was between 1‒5 mSv. All workers had average annual effctive dose lower than 20 mSv. The annual effective dose differed significantly by years （F=161.1， P<0.01）， by occupational groups （F=13.5， P<0.01）， and by hospital levels （F=264.5， P<0.01）. ConclusionThe average annual effective dose of radiation workers in medical institutions in Shanghai is lower than the national standard limit， suggesting proper and adequate radiation protection system and measures in medical institutions.
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Objective To investigate the reasons why the routine monitoring of personal dose of occupational external exposure of some radiological workers in our province reached the investigation level in 2018, so as to provide technical support for the correct decision making of administrative departments. Methods The registration forms for monitoring and verifying the personal dose of occupational external exposure were issued to radiation workers whose periodic dose reached or exceeded 1.25 mSv/ cycle. Results A total of 102 person-times were sent out in 53 verification forms, and 95 person-times were collected in 47 copies. The recovery rate was 88.68%, and 7 person-times did not feedback the verification forms. There were 15 cases of actual exposure, accounting for 15.79%, including 5 cases of radiological diagnostic staff, who did not close the protective door when operating exposure. Among them, the other 80 cases, accouting for 84.21% didn't receive actual exposure. Conclusion The vast majority of radiological workers who reached the survey level didn't receive actual exposure. 5 person-time radiological diagnostic staff, during the work did not close the protective door, subjected to abnormal radiation. Interventional medicine, nuclear medicine and industrial mobile flaw detection workers are at higher risk of abnormal exposures during their work. The suspicious results of the questionnaires without feedback were all less than the annual dose limit and the requirements of audit management. We will strengthen supervision of radiation health protection, raise the awareness of radiation protection among radiation workers, and improve radiation protection management and protection conditions for radiation workers in interventional medicine, nuclear medicine and industrial mobile flaw detection furtherly.
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Objective@#To analyze the personal dose of radiation exposure of radiation workers in some medical institutions in Tianjin, and to provide reference for radiation protection work.@*Methods@#Using cluster sampling method, 8718 radiation workers from some medical institutions (including tertiary, secondary and first-level hospitals) in Tianjin from 2014 to 2018 were selected as the subjects of investigation. Monitoring data were collected, analyzed and evaluated.@*Results@#From 2014 to 2018, a total of 8718 persons were monitored, with 14 persons (0.2%) whose annual effective dose was higher than 5 mSv; 8661 persons (99.3%) whose annual effective dose was lower than 2 mSv; 43 persons (0.5%) whose annual effective dose per capita was the highest in diagnostic radiology, which was 0.22 mSv; the annual effective dose per capita of radiation workers in primary and secondary hospitals was higher than that in tertiary hospitals; and the abnormal rate of individual dose monitoring was 73. Personnel, accounting for 0.8% of the total number of monitored personnel; the annual effective dose changes of the four types of radiation workers monitored from 2014 to 2018 showed a downward trend, and the annual effective dose of the four types of radiation workers in 2014 was the highest.@*Conclusion@#Personal dosage of radiation workers in some medical institutions in Tianjin is at a low level, and attention should be paid to diagnostic radiology workers.
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Objective To evaluate the reliability of HARSHAW-3500 thermoluminescence dosimetry system by testing its performances.Methods HARSHAW-3500 thermoluminescence dosimetry system had its performances tested and evaluated according to Verification regulation of thermoluminescence dosimetry systems used in persontal and environmental monitoring forXandgammaradiation(JJG 593-2006),Testingcriteriaofpersonneldosimetryperformanceforexternalexposure (GBZ 207-2016),Specifications for individual monitoring of occupational external exposure (GBZ 128-2016) and Thermoluminescence dosimetry systems for personal and environmental monitoring (GB/T 10264-2014),such as batch homogeneity,repeatability,linearity,incidence angle response,stability,energy response and scale factor,quantity inspection,residual dose,detection limit and etc.Results Testing results of various performance indicators proved to be within the limits according to national and industrial standards.Conclusion HARSHAW-3500 thermoluminescence dosimetry system conforms to the requirements for radiation dose measurement.It is beneficial to the improvement of quality and performance of thermoluminescence dosimetry by performances analysis and evaluation.
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Objective To evaluate the reliability of HARSHAW-3500 thermoluminescence dosimetry system by testing its performances.Methods HARSHAW-3500 thermoluminescence dosimetry system had its performances tested and evaluated according to Verification regulation of thermoluminescence dosimetry systems used in persontal and environmental monitoring forXandgammaradiation(JJG 593-2006),Testingcriteriaofpersonneldosimetryperformanceforexternalexposure (GBZ 207-2016),Specifications for individual monitoring of occupational external exposure (GBZ 128-2016) and Thermoluminescence dosimetry systems for personal and environmental monitoring (GB/T 10264-2014),such as batch homogeneity,repeatability,linearity,incidence angle response,stability,energy response and scale factor,quantity inspection,residual dose,detection limit and etc.Results Testing results of various performance indicators proved to be within the limits according to national and industrial standards.Conclusion HARSHAW-3500 thermoluminescence dosimetry system conforms to the requirements for radiation dose measurement.It is beneficial to the improvement of quality and performance of thermoluminescence dosimetry by performances analysis and evaluation.
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Purpose To develop a national registry and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation.Methods In accordance with the relevant law,regulations,standards and the current health supervision practice for radiation workers in China,to ensure more effective collection of information on individual monitoring from all levels of service providers across the country and an easy query and analysis of the collected information for both service providers and administrative institutions,the register consisted of an offline-system and a web-based information system.The off-line system consisted of 8 tables,which could easily make annual and period monitoring reports,and upload individual monitoring data in compressed and encrypted format.Web-based system consisted of 6 modules,could easily make S customized tabulations of monitoring data and show 2 trend figures.SSLVPN secure remote access was used in the system.Arranged by the Ministry of Health,training courses provided to all individual monitoring service providers and provincial administrative institutions.Results A new and individual-based national register and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation was successfully developed,and would be officially run soon.Conclusions The establishment and running of the register would be great improvement on the national radiological health reports and produce a far-reaching impact on the individual monitoring in China.