某钢铁企业放射风险评估

Radiation Risk Assessment in An Iron and Steel Corporation

目的识别和掌握某钢铁企业放射风险因素,评估其放射风险水平,为企业做好放射防护工作提供科学依据。方法通过调查企业放射防护基本情况和放射性事故历史资料,现场剂量监测,参照国家有关标准及技术规范,利用AS/NZS 4360∶1999风险评价指数矩阵法对放射风险因素进行识别、风险分析、风险评价,并提出风险处置控制对策。结果该企业放射风险因素主要源于设备设施、作业活动、作业环境和人与制度因素等4个方面。放射源有332枚,Ⅱ类、Ⅲ类高危放射源占8.73%;环境辐射剂量危害指数均小于1,但241Am-Be中子源剂量较大;近10年7起放射性事故中,放射源事故占86%。初步确定放射源丢失(被盗)和放射性物质运输超标为较大风险事件,射线装置超剂量照射、职业照射和公众人群异常照射为高风险事件。结论钢铁企业放射风险因素复杂,须健全安全防护体制和风险控制措施,加强放射工作人员安全意识,为达到企业生产安全、职业健康促进的目的提供保障。

[Objective]To identify and understand radiation risk factors in an iron and steel corporation,to assess radiation risk level,and provide scientific evidence for better protection against radiation.[Methods]Through investigation on basic radiological protection in enterprises and historical data of radiation accidents,field dose monitoring,the radiation risk factors identification,risk analysis,risk assessment were performed according to relevant national standards and technical specifications with utilization of AS/NZS 4360∶1999 risk assessment index matrix.And risk management control measures were also proposed.[Results]Radiation risk factors mainly come from 4 aspects： equipment and facilities,production activity,environment,human and regulations of management.There were 332 radiation sources in this iron and steel corporation in all,in which classⅡand Ⅲ radiation sources accounted for 8.73%;risk index（RI） of radiation dose in environment was under 1,but the dose of neutron emitter 241Am-Be was relatively high.There were 7 radiation accidents during past 10 years,and 86% were related with radiation sources.By initial analysis,the events including loss or steal of radiation sources,overproof transportation of radiation material were identified with relatively high risk;radiation overdose by facilities,occupational radiation exposure and abnormal public radiation exposure were identified as events with high risk.[Conclusion]Radiation risk factors of iron and steel corporation are complicated.Therefore,it is necessary to perfect radiation protection system and risk control measures,to increase safety awareness of radiation workers so as to ensure production safety and occupational health promotion.