NMC&A and Nuclear Criticality Safety System Integration: a prospective way for enhancement of the nuclear industry facilities safety

Now a lot of data on nuclear criticality accidents causes, parameters and consequences is acquired by US, UK, Japanese and Russian atomic industry. The accident inventory equals 22 today. Rather exhaustive survey and review of the accidents has been presented by Russian and US specialists [1,2]. The Survey’s major concluding section submits the lessons provided by the Review. One of the lessons is mandatory ensuring the nuclear materials (NM) handling and transformation control during their production and reprocessing. The lack of control is one of the causes of major accidents occurred. Nuclear materials control and accountancy (NMC&A) is purposed to their containment and safeguards and presents a basic task for any nation’s nuclear facilities. NMC&A systems cover sophisticated procedures and tools for periodic NM control within material balance areas established in specific way. These systems have major data sources as follows: in process control, periodic NM inventories, NM parameter measurements at key points. NM inventory and location data for the material balance areas provided by the inventory taking could be used for an objective assessment of nuclear safety status. On the other hand, very inventory taking involves implementing the operations contrasted with routine process operation and should be accompanied by a special consideration of nuclear criticality safety. Nuclear accident risk in atomic industry could be reduced when implementing the NMC&A procedures and tools both for NM containment and ensuring nuclear criticality safety. The presentation outlines a survey of nuclear criticality accidents due to lack of NMC control, demonstrates the need and benefits of integrating the NMC&A and nuclear criticality safety systems’ measures and elements to achieve goals posed for both systems.