Finding the dominant risk: A review of the ATHEANA method

A new human reliability analysis (HRA) method called ATHEANA, open-quotes A Technique for Human Error Analysisclose quotes as described in NUREG/CR-6350, is being developed for the U.S. Nuclear Regulatory Commission (NRC). The contribution of human errors to nuclear plant risk has long been recognized by the probabilistic risk assessment (PRA) community. Of particular concern are open-quotes errors of commissionclose quotes (EOC), which NUREG/CR-6350 describes as open-quotes errors that are associated with inappropriate interventions by operators with operating systems.close quotes When completed, ATHEANA is expected to provide guidance on identifying and quantifying the likelihood of commission errors, thus allowing the risks associated with such errors to be integrated within PRA studies. This paper provides an initial review of ATHEANA, with emphasis on the quantitative trial demonstration of the method provided in NUREG/CR-6350. The importance of HRA research to PRA is discussed in this paper in light of its regulatory impact