华龙一号核岛厂房气载放射性浓度计算及其监测阈值分析

Airborne radioactive concentration calculation and monitoring threshold value analysis of HPR1000 nuclear island building

吸入内照射是压水堆核电厂工作人员所受职业照射内照射部分的主要来源之一。为确保工作人员的受照剂量满足法规标准要求,并处于可合理达到的尽量低水平,必须对核岛厂房内气载放射性浓度进行评估、监测和控制。本文基于核电厂正常运行状态下核岛厂房气载放射性浓度计算模型,对其关键参数选取进行分析,并对气载放射性浓度的监测阈值设计进行研究,最终给出了关键参数的选择建议,同时也给出了部分气载放射性核素的监测阈值,用于关键通风系统的启停阈值设计,以对华龙一号核岛厂房内的气载放射性浓度进行准确的评估、监测和控制,进而降低工作人员的受照剂量。

Internal exposure through inhalation is one of the main sources of occupational exposures of NPP staff.In order to ensure that personnel exposure meet the requirements of regulations and standards,and be as low as reasonably achievable,airborne radioactive concentration in nuclear island building should be effectively evaluated,monitored and controlled.Based on the calculation model that is widely used to evaluate the airborne radioactive concentration in nuclear island building of NPP in normal operation,the selection process of key parameters in this calculation model is analyzed and the monitoring threshold value of airborne radioactive concentration is calculated in this paper.Suggestions on the selection of key parameters and monitoring threshold value of some airborne radioactive nuclides are finally provided for designing the threshold value of start&stop of the key ventilation system,which is helpful to accurately evaluate,monitor and control the airborne radioactive concentration in nuclear island building of HPR1000,so as to reduce the personnel exposures of NPP staff.