医用回旋加速器质量控制与安全策略探讨

医用回旋加速器为临床PET/CT检查提供正电子放射性核素,做好回旋加速器的质量控制和安全防护就是要保证回旋加速器良好稳定的运行,保证安全生产,从而提供足额且符合要求的正电子核素,这就要求做好回旋加速器的维护保养工作,同时要注重技术人员的操作培训和质量控制意识的养成,维修和备件的供应也列入回旋加速器的质控项目。本文总结了医用回旋加速器各结构维护和保养的方法,阐述了对技术人员进行操作培训,培养质量控制意识的重要性。     

某医院回旋加速器、PET-CT建设项目放射防护控制效果评价

目的 对回旋加速器、PET-CT机房的防护性能进行辐射安全性评价,并对机房和周围环境辐射水平进行检测。方法 依据国家相关的放射卫生防护标准与方法进行评价。结果 回旋加速器、PET-CT机房的屏蔽防护和安全设施符合国家相关标准的要求。结论 该回旋加速器、PET-CT机房在运行时,有关放射工作人员和机房周围公众是安全的。     

自屏蔽回旋加速器辐射剂量测定

目的检测自屏蔽回旋加速器的辐射剂量,以保障放射工作人员的安全。方法应用手提便携式辐射测量仪检测加速器室、放化实验室以及靶的拆卸和重装过程中的辐射剂量。结果加速器室、放化实验室以及靶的拆卸和重装过程中的辐射剂量在规定的安全范围之内。结论回旋加速器自屏蔽系统、合成热室、分装防护屏等具有良好的辐射屏蔽效果。     

回旋加速器放射性药物生产场所的防护设计与分析

【摘要】目的掌握回旋加速器放射性药物生产场所的辐射危害因素及其水平,为场所的防护设计和放射性药物生产的放射防护提供指导。方法以某医院引进的1台HM-20S型回旋加速器及其药物生产场所为研究对象,依据国家有关法规和技术标准确定场所中的辐射危害因素类别及场所级别,对相应的防护设施与措施进行分析和评价。结果制订出放射性药物生产场所的辐射防护设计方案,其中对热室工作区出人口采取GMP（良好作业规范）设计;估算出了控制区外围和场所关注点的辐射水平,在60mmPb厚壁工作箱内进行222GBq的18F操作时,操作位置的剂量率为9．6ixSv／h;明确了回旋加速器机房内活化产物的来源及其防护措施;带有自屏蔽的回旋加速器运行时,机房内的0,浓度远低于标准规定的职业接触限值。结论该放射性药物生产场所的防护设计充分考虑了放射性污染和外照射的防护,但其防护方案中还需对回旋加速器机房及防护门的屏蔽设计进行优化。     

某医院PET-CT中心建设项目职业病危害控制效果放射防护评价

目的 对建成的回旋加速器、PET-CT机房及周围环境辐射水平进行监测,并对结果进行评价,以保护放射工作人员和公众的健康。方法 根据国家相关法律、法规、放射卫生标准和预评价报告书进行评价。结果 回旋加速器、PET-CT机房的屏蔽防护和安全设施符合相关国家标准要求。结论 该PET-CT中心放射工作人员和公众是安全的。     

医用回旋加速器辐射剂量检测与评价

目的：检测医用回旋加速器环境辐射水平及工作人员个人剂量，检验其对环境、公众及相关工作人员的安全性。方法：以住友HM12型回旋加速器为检测对象，使用多功能辐射仪及热释光剂量计测定环境辐射剂量、个人剂量水平。结果：加速器室与迷路门口^y射线辐射水平为96．16uSv／h，中子辐射水平为85．09uSv／h，迷路与控制室门口、控制室操作台、加速器室墙外及屋顶的辐射水平达到或接近本底水平，回旋加速器操作人员人均年剂量当量为2．21mSv。结论：加速器室环境辐射剂量、操作人员个人剂量水平远低于国家标准水平，应消除对回旋加速器操作的恐惧心理，但同时也要搞好放射防护管理。     

某微型回旋加速器和PET—CT的辐射防护监测与评价

目的：对某医院微型回旋加速器及PET—CT场所内外的辐射水平进行评价，对工作人员受照剂量进行估评。发现问题提出改进建议，以保障放射工作人员与公众的健康与安全。方法：采用相关的放射卫生规范规定的方法。结果：测得了机房及配套设施周围的辐射剂量及其他相关数据，估算出了工作人员的年累积受照剂量。结论：回旋加速器自屏蔽系统、合成工作箱、分装防护屏等具有良好的辐射屏蔽效果。微型回旋加速器和PET—CT机房周围环境剂量不高，对流动人群及相邻场所的非放射工作人员不会造成辐射危害。放射工作人员年累积受照剂量，低于国家标准对职业人员规定的年剂量限值。对发现的问题提出了改进建议。     

医用回旋加速器机房放射防护与配套设施配置

本文首先阐述回旋加速器机房的工作流程、各个房间的布局、功能、防护要求,最后介绍了个人防护,以及购买设备中的注意事项。     

医用回旋加速器的基本原理与组成

主要应用拉摩定律及等时性回旋加速器的理论，对回旋加速器的基本原理进行分析，介绍了专门用于PET／CT大型诊断系统中为生产正电子药物的医用回旋加速器的基本特点与结构。     

某医院核医学科PET项目设计预审与防护效果验证

目的审查PET中心设计,验证放射防护效果,降低辐射对核医学工作人员和患者健康的影响。方法根据相关标准和资料,对某医院核医学科PET及回旋加速器系统设计布局进行审查,利用多功能辐射仪对相关工作场所进行放射性水平检测,对其放射防护效果进行验证。结果该项目总体设计合理。其中,在药物合成室的分装环节、活度室测活度环节、注射室注射环节、PET扫描时的摆位环节辐射剂量较高,应充分利用时间、距离屏蔽等综合防护措施。回旋加速器室两道防护门和迷道长度的设计是保守的。结论加强核医学设计审查与放射防护效果验证,对实现放射防护的最优化,解决新型仪器带来的辐射防护问题有重要意义。     

Radioactive by-products of a self-shielded cyclotron and the liquid target system for F-18 routine production

Routine production of F-18 radionuclide using proton beams accelerated in a cyclotron could potentially generate residual radioisotopes in the cyclotron vicinity which eventually become major safety concerns over radiation exposure to the workers. In this investigation, a typical 11-MeV proton, self-shielded cyclotron has been assessed for its residual radiation sources in the cyclotron’s shielding, tank/chamber, cave wall as well as target system. Using a portable gamma ray spectroscopy system, the radiation measurement in the cyclotron environment has been carried out. Experimental results indicate that relatively long-lived radioisotopes such as Mn-54, Zn-65 and Eu-152 are detected in the inner and outer surface of the cyclotron shielding respectively while Mn-54 spectrum is observed around the cyclotron chamber. Weak intensity of Eu-152 radioisotope is again spotted in the inner and outer surface of the cyclotron cave wall. Angular distribution measurement of the Eu-152 shows that the intensity slightly drops with increasing observation angle relative to the proton beam incoming angle. In the target system, gamma rays from Co-56, Mn-52, Co-60, Mn-54, Ag-110 m are identified. TALYS-calculated nuclear cross-section data are used to study the origins of the radioactive by-products.     

手术室护工职业暴露的危险因素及防护对策

目的 探讨手术室护工职业暴露的危险因素,针对性地制定对策,加强手术室护工的职业安全防护意识.方法 根据手术室护工职业暴露的危险因素,制定规范化的防护措施,对护工进行职业安全防护知识的培训,使其熟练应用防护技术.结果 进行防护教育后,手术室护工职业暴露自我防护意识和防护方法明显提高.结论 切实关注护工弱势群体,重视护工职业暴露防护,确保护工身心健康,防止医院感染的发生.     

Statistical analysis of historical occupational dose records at a large medical center

Routine monitoring of occupational radiation exposure is done primarily to demonstrate compliance with dose limits. Statistical analysis of past and present dose records provides a useful tool in the management of institutional radiation safety programs. In this study, a statistical analysis of annual dose records from 1985-1999 from a large tertiary care medical center with a cyclotron and radiopharmaceutical production facility is performed. A total of 6,089 annual dose records, categorized into ten occupational groups, were included in the analysis. Dose distribution is skewed, with 85% of workers receiving an annual dose of less than 1.0 mSv, while 1.3% have doses > or =10 mSv. The mean annual dose of all monitored workers during this 15-y period ranged from 0.5 to 1.2 mSv. Large variation in the mean annual dose exists among the different occupational groups. Four occupational groups were identified as relatively highly exposed, namely cyclotron and radiopharmaceutical production, cardiac catheterization, nuclear medicine, and diagnostic radiology. These four occupational groups also showed different trends in the mean annual dose. A correlation study showed that total annual collective dose has no linear association with the number of monitored workers, the number of measurably exposed workers, or the number of workers with annual dose between 0.1 to <10 mSv. Moderate correlation (r = 0.64) was observed between the annual collective dose and the collective dose of workers with an annual dose between 0.1 to <10 mSv. A strong and significant correlation (r = 0.95) exists between the total annual collective dose and both the number of workers with annual dose of > or =10 mSv and the corresponding collective dose due to these highly exposed workers. Although the fraction of these highly exposed workers is small (about 1%), they have a significant impact on the total collective dose and their contribution can be as high as 50%. Workers with annual dose of > or =10 mSv tend to concentrate in a few identified occupational groups and not across all occupational groupings. The cyclotron and radiopharmaceutical production department is of particular concern due to its high individual dose levels and increasing mean annual dose trend for the last 5 y. Radiochemists and cyclotron engineers tend to receive an annual dose exceeding the dose limit. A plot of the collective dose of highly exposed workers vs. the total collective dose shows that if a dose constraint of 10 mSv is imposed on highly exposed occupational groups, the total collective dose is expected to be about 200 person-mSv.     

某医院125I粒籽植入项目职业病危害控制效果评价

目的 对某医院¹²⁵I粒籽植入项目进行职业病危害控制效果放射防护评价,以保障放射工作人员和公众的健康与安全。方法 按国家《建设项目职业病危害放射防护评价报告编制规范》GBZ/T 181-2006进行评价。结果 该院¹²⁵I粒籽植入项目的屏蔽和安全防护措施符合国家相关标准要求。结论 该院¹²⁵I粒籽植入项目在正常运行时,能够保障放射工作人员和公众的健康与安全。     

‘They won't change it back in their heads that we're trash’: the intersection of sex work‐related stigma and evolving policing strategies

In Vancouver, Canada, there has been a continuous shift in the policing of sex work away from arresting sex workers, which led to the implementation of a policing strategy that explicitly prioritised the safety of sex workers and continued to target sex workers’ clients. We conducted semi‐structured interviews with 26 cisgender and five transgender women street‐based sex workers about their working conditions. Data were analysed thematically and by drawing on concepts of structural stigma and vulnerability. Our results indicated that despite police rhetoric of prioritising the safety of sex workers, participants were denied their citizenship rights for police protection by virtue of their ‘risky’ occupation and were thus responsiblised for sex work related violence. Our findings further suggest that sex workers’ interactions with neighbourhood residents were predominantly shaped by a discourse of sex workers as a ‘risky’ presence in the urban landscape and police took swift action in removing sex workers in the case of complaints. This study highlights that intersecting regimes of stigmatisation and criminalisation continued to undermine sex workers citizenship rights to police protection and legal recourse and perpetuated labour conditions that render sex workers at increased risk for violence and poor health.     

某医院X射线影像诊断职业病危害控制效果评价

目的对某医院新建建设项目进行职业病危害控制效果放射防护评价,以保障放射工作人员和周围公众的健康与安全。方法按国家《建设项目职业病危害放射防护评价报告编制规范》GBZ/T181-2006进行评价。结果该院新建建设项目的屏蔽和安全防护措施符合国家相关标准要求。结论该院新建建设项目在正常运行时,能够保障放射工作人员和周围公众的健康与安全。     

克拉玛依市含密封源仪表放射防护状况调查

目的了解克拉玛依市含密封源仪表放射防护状况,加强放射作业人员对密封源的安全防护意识和管理,确保放射工作人员与公众的安全与健康。方法对克拉玛依市含密封源仪表的分布、应用状况及辐射防护水平进行调查,评价全市含密封源仪表的安全性及放射防护状况。结果含水监测仪的剂量较低,距源容器表面5 cm处的剂量为0.00~0.45μGy/h,距源容器表面100 cm处及操作人员处剂量为0.00~0.08μGy/h。井下压裂的剂量较高,距源容器表面5 cm处的剂量最高达157.00μGy/h,距源容器表面100 cm处的剂量为0.54~6.00μGy/h;操作人员处的剂量为0.06~4.20μGy/h。结论克拉玛依市含密封源仪表防护状况较好,符合国家标准。应加强流动性较大的放射源的安全防护监管,防止不必要的照射,并应配备监测仪器以防意外照射。