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Objective To investigate the actual situation and problems faced by radiological professionals in implementing The Specification of Radiological Protection Assessment for Occupational Hazard in Construction Project Part 2: Radiotherapy Facility (GBZ/T 220.2—2009). Methods A questionnaire survey was performed on radiological professionals who were selected, using the multi-stage stratified sampling method, from those who had participated in the assessment for occupational hazard in the construction project of radiotherapy facility from seven provinces and cities in China. A descriptive statistical analysis was used to analyze the general information and the awareness, promotion, and implementation of the standard of the participants. The chi-squared test was used to compare the data of different regions. Results A total of 173 radiological professionals from seven provinces and cities were investigated. They had a relatively high awareness rate (98.8%) of the standard, but a relatively low training and promotion rate (65.3%) of the standard. There were no significant differences in the awareness rate and the training and promotion rate between different regions (χ2 = 2.743, P = 0.602; χ2 = 5.584, P = 0.061). The use frequency of the standard was relatively low among the radiological professionals, and 64.9% of them thought that it was necessary to revise the standard, especially to further refine the scope of application, key technical indicators such as assessment methods, and radiological protection management regulations. Conclusion The training and promotion of the standard should be strengthened among radiological professionals. Some key technical indicators in the standard should be clarified and refined.
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Background Cumulative risk index (CRI), as a commonly used approach to estimate the joint effects of multiple air pollutants on health, has been used by few studies to construct an air quality health index (AQHI). Objective To construct an AQHI based on the CRI of air pollution in Tianjin and evaluate the validity of the AQHI. Methods Daily data on air pollutants, meteorological factors, and non-accidental deaths during 2015–2019 in Tianjin were collected to create a time-series object. Descriptive statistical analyses were used to describe the characteristics of the data. To determine the best lag day and indicative pollutant, single-pollutant and two-pollutant generalized additive models were fitted to construct the exposure-response relationships between air pollutants and non-accidental deaths. After that we evaluated a CRI of air pollution using multi-pollutant models and constructed an AQHI and its classifications based on the CRI. Finally, we compared the exposure-response associations and coefficients of the AQHI and the conventional air quality index (AQI) with non-accidental deaths, and evaluated the health risk communication validity of the AQHI using generalized cross validation (GCV) values and R2 values. Results We selected lag1 as the best lag day and PM2.5, SO2, NO2 and O3 as the appropriate pollutants according to the unqualified rates of pollutants and significant statistical results. One μg·m−3 increase of PM2.5, SO2, NO2, and O3 was associated with −0.00002, 0.00079, 0.00015, and 0.00042 increase in effect size b of the non-accidental mortality, respectively. Based on these coefficients, we calculated the CRI and AQHI. According to a pre-determined classification scheme of the AQHI, the air quality of 63% study days was low risks and that of 34% study days was median risks. The associations of AQHI and AQI with non-accidental deaths in different populations were evaluated. The results showed that the excess risks of non-accidental deaths in total, female, and male populations for per interquartile range (IQR) increase in AQHI were higher than the corresponding values of AQI. The GCV values of the AQHI model (2.694, 1.819, and 1.938, respectively) were lower than those of the AQI model (2.747, 1.850, and 1.961, respectively), and the R2 values of the AQHI model (0.849, 0.780, and 0.820, respectively) were higher than those of the AQI model (0.846, 0.776, and 0.817, respectively). Conclusion Compared with AQI, the CRI-based AQHI may communicate the air pollution-related health risk to the public more effectively in Tianjin.
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Objective:To verify radiation shielding effect of the maze of the CyberKnife room, so as to identify and correct the deficiencies in the shielding designs in certain circumstances.Methods:In line with the radiation protection shielding design scheme of the CyberKnife room provided by the producer, the consideradtions are focused on the useful beam that could mainly pass through the image center, but not the outer wall of the maze. However, during the inspection and acceptance of radiological protection in the built room, it was found that in a certain situations useful wire did not pass through the imaging center. Therefore, the additional shielding and protection facilities were built and verified.Results:After verification and acceptance on the scene, in the case where the useful beam was passing through the image center, the highest ambient dose equivalent rate at the concerned points 30 cm away from the outer wall of the maze was 0.31 μSv/h, less than the control level 10 μSv/h. In the opposite case, the highest ambient dose equivalent rate at the same points as above was 301.67 μSv/h, ablut 30 times as much as the control level. After the thickness in maze outer wall was enhanced, the highest ambient dose equivalent rate at the same as above was 2.14 μSv/h. This testing result met the concerned national standard.Conclusions:It is desirable that in designing the outer wall shielding in the maze in a CyberKnife room, attention should be paid to whether or not the useful beam could pass through the image center, or otherwise directly irradiate on the maze on the basis of the movement range of the accelerator. Shielding wall thickness should be calculated on the basis of the irradiation ragne and the distance between source location and the concerned points to ensure being in compliance with the requirements of the concerned national standard. Meanwhile, it should protect the workers occupying at the concerned locations from receiving higher radiation doses.
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Objective To assess the frequency of medical exposure from X-ray diagnostic equipment in Tianjin,and provide recommendations for regulating medical radiation management and rational allocation and use of medical and health resources.Methods Using the census method,questionnaries were issued in the form of an administrative document to investigate the basic information on X-ray diagnostic equipment and medical procedure frequency in 687 hospitals (excluding military and armed police hospitals) in 2018.Mean values of frequencies were derived by dividing the number of procedures for each type of X-ray equipment by the total number of permanent residents.Results There were 1 562 pieces of X-ray diagnostic equipment (including interventional radiology),with an average of 1.00 unit per 10 000 population.There were 4 782 radiation workers engaged with X-ray diagnostic work (including interventional radiology),averaged on 3.06 workers per unit,with the highest of 5.25 workers per unit in tertiary hospitals and the lowest of 1.18 in ungraded hospitals.The city's X-ray diagnostic medical exposure came from 8 905 970 medical procedures,including 54.81％ for tertiary hospitals,18.00％ for secondary hospitals,16.21％ for primary hospital,and 10.98％ for ungraded hospitals.X-ray photography contributed 71.30％ with annual frequency of 407.84 examinations per 1 000 population,CT scans 21.81％ with annual frequency of 124.74 examinations per 1 000 population,interventional radiology 1.04％,with annual frequency of 5.98 examinations per 1 000 population,and other types of X-ray examinations 5.85％ with annual frequency of 33.47 examinations per 1 000 population.Conclusions The configuration of X-ray diagnostic equipment in Tianjin is basically reasonable.The frequency of X-ray diagnostic medical exposure is increasing year by year.The rationality of the distribution of X-ray diagnostic examinations needs to be further improved.To reduce dose to population,for the public health and safety is important issues in the future of radiation protection.
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Objective@#To investigate the usage frequency of radiological diagnosis devices in ten hospitals in Tianjin, China, and to provide a basis for the survey of medical radiation frequency in Tianjin.@*Methods@#Ten hospitals from the ten districts in Tianjin were enrolled as subjects by a convenient sampling method. A survey was conducted to assess the general information and radiological diagnosis device information and usage frequency in those hospitals in 2016. The radiological examination frequency in Tianjin was estimated.@*Results@#A total of 610 458 patients received radiological examinations in the sampled hospitals in 2016. In those patients, 371 882 received X-ray examinations for imaging and 238 576 for computed tomography (CT) ; there were slightly more female patients than male patients, suggesting a relatively equal gender distribution; patients older than 40 years accounted for 65.53%, which was the highest among all the age groups. Different types of radiological diagnosis devices were mostly used in tertiary and secondary hospitals. In Tianjin, the estimated frequency of X-ray examination for imaging and CT scanning was 451 and 188 per thousand people, respectively, in 2016.@*Conclusion@#The frequency of radiological diagnosis is relatively high in the ten hospitals in Tianjin. The investigation of medical radiation in Tianjin needs to be improved.
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Objective:A database was designed and developed for effective utilization monitoring data of radiation dose to patients and occupational operators in cardiovascular interventional procedures. Methods:To complete a command reception of the client program, data display and other functions, compiled database software using MS Visual Basic level programming language. Using MS Access database completed data storage, management and maintenance. Results:The database was designed according to technological indicator acknowledged;the relevant help file was set up. The database includes two sub-libraries professional database and patient database. Professionals and patients can be recorded separately input, record view and record query. Conclusion:The data platform for monitoring data of radiation dose in cardiovascular interventional procedures was provided, which can provide basic data for constituting normalization and technical standard of dose limited of radiation dose to patients and occupational operators in cardiovascular interventional procedures.