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.

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.

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.

The quality of the water environment is one of the most important factors that can directly affect the health of human beings and other non-human species. The levels of the radionuclides in water environment are the key indicator while assessing the quality of water environment. Recently, with the development of the nuclear energy in China, the public people have paid a focus attention on the levels and the health risks of the radionuclides. This paper introduced the sources, the health effects, the health risk assessment methods and the current status of the health risk assessment study about the radionuclides, in order to provide basis for the health risk assessment of radionuclides in water environment and the protection of human health.

The quality of the water environment is one of the most important factors that can directly affect the health of human beings and other non-human species. The levels of the radionuclides in water environment are the key indicator while assessing the quality of water environment. Recently, with the development of the nuclear energy in China, the public people have paid a focus attention on the levels and the health risks of the radionuclides. This paper introduced the sources, the health effects, the health risk assessment methods and the current status of the health risk assessment study about the radionuclides, in order to provide basis for the health risk assessment of radionuclides in water environment and the protection of human health.

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.

Objective:To investigate the application of GBZ/T 220.2-2009 "The Specification of Radiological Protection Assessment for Occupational Hazard in Construction Project-Part 2: Radiotherapy Facility" in health management institutions, and to understand the scientificity, practicability and problems existing in the implementation of the standard.Methods:The method of multistage stratified sampling and questionnaire survey were used to collect the standard application status among 96 radiological health managers who had participated in the evaluation of radiotherapy facility construction projects in 6 provinces and cities from November 2020 to April 2021. A descriptive statistical analysis method was used to analyze the basic information of the survey object, the knowledge of the standard, the publicity and implementation of the standard.Results:The radiological health management personnel mainly came from health supervision agencies (62.5%, 60/96) , and 86.5% (83/96) were engaged in the pre-evaluation of radiotherapy device construction project and the approval and supervision of control effect evaluation. The awareness rate and training rate of radiological health managers on GBZ/T 220.2-2009 were 88.5% (85/96) and 31.3% (30/96) , respectively. 89.6% (86/96) managers thought it could meet the needs of radiotherapy facility construction project approval or supervision. 49.0% (47/96) of managers believed that the standard needed to be revised.Conclusion:The content of GBZ/T 220.2-2009 is basically scientific and reasonable, but the publicity, implementation and training of radiological health administrator still need to be strengthened. It is suggested to revise some clauses in the standard that do not meet the requirements.

Objective:To study the level of CT dose to paediatric patients in Tianjin, and to provide basic data for establishing the diagnostic reference levels for paediatric patients from CT examinations in Tianjin.Methods:In 2022, a general survey was carried out of the CT doses to the head, chest, abdomen and pelvis of the scanned paediatric patients in two tertiary pediatric hospitals and seven tertiary general hospitals in Tianjin. The scanned pediatric patients were divided into four age groups in terms of the age of -1, -5, -10 and -15 years, and 20 patients were investigated in each age group in each hospital. The basic information were collected on the scanned patients, CT scanning parameters, volume CT dose index (CTDI vol), dose length product (DLP), and the differences in CTDI vol and DLP on the same site among different age groups and different types of hospitals were analyzed. Results:There were significant differences in CTDI vol and DLP between different age groups at the same site (head, chest, abdominal and pelvic, CTDI vol:χ2=296.51, 193.82, 291.72, P<0.001; DLP: χ2=291.22, 263.63, 344.97, P<0.001). There were significant differences in CTDI vol and DLP among different types of hospitals on the same site (head, chest, abdominal and pelvic, CTDI vol:Z=-13.13, -7.57, -15.27, P<0.001; DLP: Z=-9.07, -6.15, -11.57, P < 0.001). Conclusions:The 75 th percentile values of CTDI vol and DLP for pediatric head, chest, abdomen and pelvis CT scanning in tertiary hospitals in Tianjin are at a good level, and the dose on some examination sites are relatively high. Further optimization of pediatric CT scanning procedures is necessary.

Objective:To investigate the application of GBZ/T 220.2-2009 "The Specification of Radiological Protection Assessment for Occupational Hazard in Construction Project-Part 2: Radiotherapy Facility" in health management institutions, and to understand the scientificity, practicability and problems existing in the implementation of the standard.Methods:The method of multistage stratified sampling and questionnaire survey were used to collect the standard application status among 96 radiological health managers who had participated in the evaluation of radiotherapy facility construction projects in 6 provinces and cities from November 2020 to April 2021. A descriptive statistical analysis method was used to analyze the basic information of the survey object, the knowledge of the standard, the publicity and implementation of the standard.Results:The radiological health management personnel mainly came from health supervision agencies (62.5%, 60/96) , and 86.5% (83/96) were engaged in the pre-evaluation of radiotherapy device construction project and the approval and supervision of control effect evaluation. The awareness rate and training rate of radiological health managers on GBZ/T 220.2-2009 were 88.5% (85/96) and 31.3% (30/96) , respectively. 89.6% (86/96) managers thought it could meet the needs of radiotherapy facility construction project approval or supervision. 49.0% (47/96) of managers believed that the standard needed to be revised.Conclusion:The content of GBZ/T 220.2-2009 is basically scientific and reasonable, but the publicity, implementation and training of radiological health administrator still need to be strengthened. It is suggested to revise some clauses in the standard that do not meet the requirements.

Objective:To understand the level of radiation doses from digital mammography in Tianjin and the associated influencing factors.Methods:The stratified quota sampling method was used for analysis of 374 digital mammography-examined individuals by using 12 digital mammography devices in 12 selected medical institutions. The examinations were carried out in terms of exposure positions[(craniocaudal (CC) and mediolateral oblique (MLO)], compressed breast thickness, tube voltage, time product of tube current (mAs) and target/filter.Results:The median age of the examined individuals in this survey was 43 years, the median tube voltage (kV) was 29 kV, the median tube current time product was 60.3 mAs, the median compressed breast thickness was 48 mm, and the median average glandular dose (AGD) was 1.32 mGy. The mean dose to the analyzed glandular tissue in the conditions of different target/filters varies in the descent order of Mo/Mo > Mo/Rh > Rh/Rh > W/Rh > W/Al, with the difference being statistically significant difference ( χ2=885.90, P<0.05). The mean dose to the glandular tissue increased with the increase in compressed breast thickness, and the difference was statistically significant ( χ2=31.58, 8.56, 76.13, 118.47, 24.09, P<0.05). Conclusions:The median average glandular dose in Tianjin was 1.32 mGy. This level is lower than in Guangxi province and Fuzhou city, similar to that in Beijing and Guangdong province, and lower than the national survey result of average breast dose. The efforts should be dedicated to further strengthening the research on the related factors of the average glandular dose in order to protect the health and safety of the examined individuals.