摘要
目的探讨某大型辐照装置运行中的辐射防护状况及异常工况下控制区内辐射剂量分布,分析其辐射风险。方法以运行中的某大型辐照场为研究对象,使用AT1121型X、γ剂量率仪测量贮源状态及正常辐照状态下辐照场内及毗邻场所的辐射剂量水平;使用热释光剂量计(TLD)测量异常工况下(源升起至辐照位并迅速降源至水井中贮源位置)辐照场内不同关注点位的剂量分布;依据国家标准,查验辐照场设置的辐射安全设施,分析、评价其辐射风险。结果贮源状态下辐照场内辐射剂量水平和正常辐照状态下辐照场监督区辐射剂量水平均为0.09~0.11μSv/h,均处于环境本底水平;异常工况下辐照场控制区内辐射剂量水平为辐照场内>迷路内口转角>迷路内,剂量范围分别为1.0~101.3 Sv、32.7~514.0 mSv、8.7~183.2μSv,迷路外口已接近本底水平。结论该辐照装置正常运行中,场所防护水平满足国家标准要求;异常工况下辐照场内误留将引发严重辐射损伤;若出现人员误留辐照室内,应第一时间向迷路内逃离,并于逃离过程迅速启动应急防护措施,减少辐照场内受照时间并确保启动降源操作。
Objective To explore the present state of radiation protection in an operational large-sized irradiation facility and the distribution of incurred radiation doses in the controlled area under abnormal conditions,and to analyze the acompanied radiation risk.Methods With an irradiation facility in operation as the research object,the radiation doses were measured using AT1121 X and gamma dose rate meters for the soruce both in working and storage.Thermoluminescent dosimeters(TLDs)were used to measure the dose distribution in an irradiation field under abnormal conditions.The radiation safety features were checked against the several relevant national standards,with the radiation risks evaluated.Results The radiation dose rates were in the range of 0.09-0.11μSv/h,lower than the environmental background level whether in storage or working.Under abnormal working conditions,the radiation dose values from high to low were 1.0-101.3 Sv,32.7-514.0 mSv and 8.7-183.2μSv in the irradiation field,respectively.At the outside maze,the doses were close to the background level.Conclusions The protection features of the irradiation facility meet the requirements of the relevant national standards.Under abnormal conditions,radiation could cause serious damages to the persons staying in the irradiation field.These persons were suggested to access to maze as soon as possible to reduce the exposure time,and activate the emergency protection equipments to deescalate the ^(60)Co source onto the well.
作者
王宏芳
冯泽臣
王欢
白斌
翟曙光
马永忠
Wang Hongfang;Feng Zechen;Wang Huan;Bai Bin;Zhai Shuguang;Ma Yongzhong(Beijing Center for Disease Prevention and Control,Beijing 100013,China)
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2023年第3期204-208,共5页
Chinese Journal of Radiological Medicine and Protection
基金
北京市高层次公共卫生技术人才建设项目(学科带头人-01-20)。
关键词
辐照装置
剂量当量
放射防护
Irradiation facility
Dose equivalent
Radiation protection
