Objective:To formulate refined management strategies to improve the operation quality and protective effect of medical X-ray diagnosis equipment based on the risk analysis of the correlation of medical X-ray diagnostic equipment.Methods:The used 41 medical X-ray diagnosis equipment in Fuwai Hospital,Chinese Academy of Medical Sciences from January 2022 to December 2023 were selected.According to different management modes for equipment,they were managed respectively by the conventional management mode(20 units)and the management mode with risk analysis of the correlation(21 units).The risk grades of correlation of management mode with risk analysis of the correlation were classified on the basis of the probability of risk and the degree of harm in medical X-ray diagnosis equipment.The protection management of equipment was conducted from three aspects included the location of equipment,the staffs and subjects.A self-made questionnaire was used to investigate the satisfactions of engineers of using management for equipment,operators,and staffs of operating and maintaining equipment for the two kinds of management modes.The protection quality,failure rate of equipment,and qualification rate of protection of medical X-ray diagnosis equipment under different management modes were compared.Results:The quality scores of operation safety,regular inspection,maintenance and repair,and shielding protection for radiation of medical X-ray diagnosis equipment that adopted the management mode with risk analysis of the correlation were respectively(92.14±3.36),(91.47±2.41),(92.54±3.32)and(91.69±3.57)points,all of which were higher than those of the conventional management mode,and the differences of them were statistically significant(t=16.396,17.368,19.688,14.401,P<0.05).The failure rate of the 21 medical X-ray diagnosis equipment that adopted the management mode with risk analysis of correlation was 0,which was lower than 20.00%of the conventional management mode.The qualified rate of protection was 95.23%,which was higher than 70.00%of the conventional management mode,and the differences of them were statistically significant(x2=4.654,4.608,P<0.05).The satisfaction scores of engineers of using equipment,operators and staffs of operating and maintaining equipment for the protective effect of adopting the management mode with risk analysis of correlation were respectively(94.69±4.02),(93.21±4.36)and(92.54±3.47)points,all of which were higher than those of the conventional management mode,and the differences were statistically significant(t=16.902,11.291,12.020,P<0.05).Conclusion:The process-based protection management strategy on the basis of risk analysis of correlation for medical X-ray diagnosis equipment can prevent risks of medical X-ray diagnostic equipment,and improve the operation quality of the equipment,and reduce the operation risks of the equipment,and maximize the enhancement for management quality of medical X-ray diagnosis equipment.

Objective To analyze the layout and shielding effectiveness of medical accelerator vaults, and to provide a reference for the layout, shielding design, and optimization of protection of medical accelerator vaults. Methods Four medical accelerator radiotherapy vaults were selected. The layouts of these vaults were compared with the layout requirements in the radiation therapy protection standards. For each vault, the dose rates at four points of interest outside the shielding were calculated, including the primary shielding area, secondary shielding area, maze outer wall, and lateral shielding area. These values were then compared with the actual measurements obtained using a dose rate meter. Results All four vaults were located on the ground floor of the building and included a maze, with the auxiliary rooms all placed outside the treatment rooms. However, one vault was not located at one end of the building, and in another vault, the control room was exposed to direct irradiation of the useful beam. The calculated dose rates outside the primary shielding area ranged from 0.04 μSv/h to 0.62 μSv/h, while the measured values ranged from 0.10 μSv/h to 0.66 μSv/h, with the measured values being higher than the calculated ones. The calculated dose rates outside the secondary shielding area ranged from 0.0005 μSv/h to 0.12 μSv/h, those outside the maze outer wall ranged from 0.06 μSv/h to 0.18 μSv/h, and those outside the lateral shielding area ranged from 0.009 μSv/h to 0.15 μSv/h; the measured values were all below the detection limit. Conclusion Inadequate layouts were observed in some of the accelerator vaults. The calculated and measured dose rates at points of interest outside the vaults were both significantly lower than the shielding protection requirements in standards, indicating that the shielding designs were overly conservative. Construction units should follow the principle of optimization of radiation protection to design the layout and shielding reasonably and pay attention to the underestimation of dose rates outside the primary shielding caused by the tenth value layer.

Objective To investigate the annual effective doses to radiation workers caused by radon concentrations in the underground workplaces of medical institutions, and to provide a scientific basis for the prevention and control of indoor radon in underground places. Methods A typical sampling method was used to select 5-30 medical institutions in each of Hunan, Jiangxi, Guizhou, Hubei, and Sichuan provinces. A total of 66 monitoring points in 66 medical institutions were selected. The indoor radon concentrations in underground workplaces were measured cumulatively using CR-39 solid nuclear track detectors. The radiation dose to radiation workers was estimated according to the method outlined in the Requirements for control of indoor radon and its progeny (GB/T 16146—2015). The Kruskal-Wallis H test was used to compare the differences in indoor radon concentrations between different provinces. Results The average indoor radon concentration in the underground workplaces of 66 medical institutions was 69.8 Bq/m³, with the highest being 147.6 Bq/m³. The average indoor radon concentrations in the underground workplaces of medical institutions in Sichuan, Guizhou, Hubei, Jiangxi, and Hunan were 72.1, 83.2, 66.6, 88.4, and 61.5 Bq/m³, respectively. The annual effective doses to radiation workers caused by radon concentrations in underground workplaces were 0.57-0.83 mSv, with an average of 0.69 mSv. There was a significant difference in radon concentrations among provinces (P < 0.05). Conclusion The indoor radon concentrations and personnel exposure doses in the underground workplaces of monitored medical institutions comply with national control standards. However, continuous monitoring and necessary indoor radon prevention and control measures are still needed.

Objective To establish typical values for interventional diagnosis and treatment at our institution, use these values as a tool to evaluate patient medical exposure doses, and optimize radiation protection measures. Methods From June to December 2023, we collected information on 593 adult cardiovascular interventional diagnosis and treatment surgeries, including surgery type, equipment model, air kerma-area product (KAP), incident reference point air kerma (K_a,r), perspective time (FT), and exposure mode. Results The typical value of cardiovascular interventional diagnosis at our institution in 2023 was 27.5 Gy·cm². The typical value of cardiovascular interventional treatment was 70.0 Gy·cm². The FT, KAP, and K_a,r of interventional surgeries were significantly higher than those of interventional diagnosis (P < 0.01). There were significant correlations between FT, KAP, and K_a,r (P < 0.01). Conclusion The results of this study were slightly different from those of other studies. They provide typical data and reference values for cardiovascular interventional diagnosis and treatment dose levels in Beijing and are helpful for dose optimization between different medical institutions.

Objective To evaluate the current status in the implementation of GBZ/T 201.5-2015 Radiation shielding requirements for radiotherapy rooms-Part 5: Radiotherapy room of proton accelerators, identify issues in the application of its technical indicators, and provide a basis for the in-depth implementation and further revision of the standard. Methods In accordance with the Standardization Law of the People’s Republic of China and the Guidelines for Health Standards Tracking Evaluation (WS/T 536-2017), a combination of cluster sampling and stratified sampling methods was employed to select professionals involved in proton accelerator radiotherapy devices and facilities in three provinces (or municipalities directly under the central government) as the subjects of the survey. A questionnaire was developed to collect basic information about the subjects and their understanding and application of the technical indicators in the standard. A standard evaluation indicator system with a total score of 100 points was established to score the implementation of the standard (40 points), the technical content (30 points), and the effectiveness of the implementation (30 points). Results A total of 169 professionals from 107 institutions participated in the survey, with 79.88% of the respondents having at least 5 years of experience in radiation therapy and 74.56% holding intermediate or higher professional titles. The score of standard implementation was 18.3 points. The awareness rate exceeded 80%, indicating a high level of awareness about the standard. However, the scores for the dissemination and application of the standard were relatively low, accounting for 28% and 32% of their respective full marks. The technical content of the standard and the effectiveness of its implementation scored 27.0 and 26.6 points, respectively. The overall score in the evaluation of standard implementation was 72 points, with scores of 68.6, 72.3, and 75.0 for Beijing City, Shanghai City, and Jiangsu Province, respectively. Conclusion GBZ/T 201.5-2015 Radiation shielding requirements for radiotherapy rooms-Part 5: Radiotherapy room of proton accelerators is scientific and operable, and it is well-coordinated with relevant laws and standards. However, considering the development in FLASH technology and multi-chamber radiotherapy room, it is necessary to revise and improve the standard.

Objective To track and evaluate the implementation and application of the occupational health standard Radiation shielding requirements for radiotherapy room—Part 4: Radiotherapy room of ²⁵²Cf neutron afterloading (GBZ/T 201.4-2015) by radiation health technical service agencies, medical institutions, health supervision agencies, and radiotherapy facility design units, and to provide a scientific basis for the further revision and implementation of this standard. Methods Following the Guideline for health standards tracking evaluation (WS/T 536-2017) and the project implementation plan, relevant practitioners were randomly selected for a questionnaire survey. The survey primarily focused on their awareness, standard training, application, and revision suggestions of GBZ/T 201.4-2015. The results were summarized and analyzed. Results A total of 168 evaluation questionnaires were collected from relevant practitioners in 28 provinces. Only 31.6% of the respondents reported being “well familiar” or “ familiar” with the standard, 27.4% of the respondents believed that the standard was widely used, and 45.2% of the respondents believed that the standard could meet the needs of their work. Only 14.9% of the respondents had received relevant training on the standard, more than half of the respondents had not applied the standard within the past 10 years, and 45.2% of the respondents believed that the standard "needs to be revised". Conclusion Due to the small number of californium-252 neutron afterloading radiotherapy devices in operation on the market, the overall awareness of the standard is low, suggesting that relevant authorities need to strengthen training and publicity of the standard, and that certain sections of the standard need to be revised or merged.

Objective To investigate the levels of radionuclides in food in Beijing, China, and assess the committed effective dose to local residents from food intake. Methods From 2021 to 2022, a total of 65 food samples across 7 categories were collected in Beijing. The activity concentrations of radionuclides, including ¹³⁷Cs, ²¹⁰Pb, ²³⁸U, ²²⁸Ra, ²²⁶Ra, ⁴⁰K, ⁹⁰Sr, ²¹⁰Po, ³H and ¹⁴C, were measured using gamma spectrometry and radiochemical methods. By combining the monitoring results with dietary consumption data of Beijing residents and the internal dose coefficients for Chinese reference adult phantom, the committed effective dose was estimated. Results The levels of radionuclides in food in Beijing were within the normal background range, consistent with related surveys in China and abroad, with activity concentrations below national standard limits. No significant differences were found in the activity concentrations of ¹³⁷Cs, ²³⁸U, ²²⁸Ra, ²²⁶Ra and ⁴⁰K between food samples collected from key areas and those from control areas (P > 0.05). The committed effective doses calculated according to internal dose coefficients for Chinese reference adult male phantom and GB 18871-2002 were 0.26 mSv and 0.19 mSv, respectively. Based on the Chinese reference adult male phantom, the majority of the committed effective dose was attributed to ²¹⁰Pb (45.1%), ²²⁸Ra (37.1%), ²¹⁰Po (12.3%), and ²²⁶Ra (4.7%). Conclusion The levels of radionuclides in food in Beijing fluctuated within the background range, resulting in a low radiation dose burden to the population.

Objective:To investigate the doses received by radiation workers from external and internal exposures during the production of 125I seed source, and to provide scientific basis for accurate evaluation of the annual doses of radiation workers. Methods:The production site and radiation workers of a 125I seed source production enterprise were determined as the survey objects. An AT1121 X/γ dosimeter was used to measure the ambient dose equivalent rate on the operation site such as welding and cleaning of the seed source, and the dose received by workers from external exposure was estimated. LiF (Mg, Cu, P) TLD dosimeters were used to measure the external doses to workers in a specific period. The doses obtained by the two method were compared and analyzed. The RG-50 air sampler and TC-30 iodine box were used to collect the workplace air, The activity concentration of 125I in the air was measured by using of the BE5030 high-purity germanium gamma spectrometer to estimate the internal dose to workers. The evaluation of doses was performed in accordance with the national standards GBZ 128-2019 and GBZ 129-2016. Results:The estimated annual dose to the worker′ hands is 24.5 mSv/year. The estimated maximum dose was 2.61 mSv/year. The maximum value of individual dose monitored was 2.42 mSv/year, basically consistent with the measured value on the basis of considering the actual work rotation. The maximum estimate of committed effective dose from internal exposure was 1.55 mSv, by a factor of up to 17 times the estimated external dose at the corresponding post.Conclusions:The radiation dose to the radiation workers’ hands is relatively high in the production of 125I seed source, so the protective measures for hands should be effectively strengthened. Meanwhile, the internal dose to the workers in the production process of 125I seed source should not be negelected. The ventilation of the site should be strengthened, the air flow direction should be planned, and the 125I activity concentration in the air should be regularly monitored.

Objective To systematically explore the prescription source,prescription composition,drug origin and processing,functional indications and clinical application of the classic Tibetan medicine Sanwei Qiangwei Powder,so as to provide scientific basis for its in-depth development,rational utilization and follow-up research.Methods By using methods of literature review,the ancient and modern Tibetan medical classics and modern literature such as'Ocha Jinmai' sporadic secret collection 'Zhigong Yi Suan Ji' were retrieved,and the prescription origin,medicinal material origin,processing technology,prescription solution,usage and dosage were studied and analyzed.Results The Sanwei Qiangwei Powder originated from the 'Ocha Jinmai'(《()》)written by Qiangba Minimatongwatundan in the 15th century.The book was written much earlier than the literature included in the 'Catalogue of Ancient Classic Prescriptions(Second Batch)'-the 'Selection of Tibetan Medicine Prescriptions·Longevity Baoru' in the 19th century.The prescription consists of 15 copies of Rosa rugosa,7 copies of Herpetospermum caudigerum,and 3 copies of Terminalia chebula Retz.It plays a significant effect on hepatobiliary diseases such as biliary fever,liver fever,primary headache,and headache after drinking in clinical practice.It is the core prescription for the treatment of Chiba-type diseases and has high development value.There are differences in the use site,dosage ratio,usage and dosage of medicinal materials in different literatures,and the dosage has been clarified by textual research and expert consultation.Conclusion This study sorted out and clarified the key information of Sanwei Qiangwei Powder,which laid a theoretical foundation for the inheritance and development,innovative application and modernization research of the prescription.

Objective:To investigate the doses received by radiation workers from external and internal exposures during the production of 125I seed source, and to provide scientific basis for accurate evaluation of the annual doses of radiation workers. Methods:The production site and radiation workers of a 125I seed source production enterprise were determined as the survey objects. An AT1121 X/γ dosimeter was used to measure the ambient dose equivalent rate on the operation site such as welding and cleaning of the seed source, and the dose received by workers from external exposure was estimated. LiF (Mg, Cu, P) TLD dosimeters were used to measure the external doses to workers in a specific period. The doses obtained by the two method were compared and analyzed. The RG-50 air sampler and TC-30 iodine box were used to collect the workplace air, The activity concentration of 125I in the air was measured by using of the BE5030 high-purity germanium gamma spectrometer to estimate the internal dose to workers. The evaluation of doses was performed in accordance with the national standards GBZ 128-2019 and GBZ 129-2016. Results:The estimated annual dose to the worker′ hands is 24.5 mSv/year. The estimated maximum dose was 2.61 mSv/year. The maximum value of individual dose monitored was 2.42 mSv/year, basically consistent with the measured value on the basis of considering the actual work rotation. The maximum estimate of committed effective dose from internal exposure was 1.55 mSv, by a factor of up to 17 times the estimated external dose at the corresponding post.Conclusions:The radiation dose to the radiation workers’ hands is relatively high in the production of 125I seed source, so the protective measures for hands should be effectively strengthened. Meanwhile, the internal dose to the workers in the production process of 125I seed source should not be negelected. The ventilation of the site should be strengthened, the air flow direction should be planned, and the 125I activity concentration in the air should be regularly monitored.