Evaluation of severe accident risks: Methodology for the containment, source term, consequence, and risk integration analyses; Volume 1, Revision 1

Abstract

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Uncertainty quantification approaches for advanced reactor analyses.

“…This method has the drawback of often being very expensive to apply, but it is one of the most straightforward and therefore economical to implement, and all statistical evaluation methods may be rigorously used on the resulting sample space [Devictor 2005]. It will also correctly account for any discontinuities and transitions between physical regimes, can incorporate correlations between input parameters, and works well for input parameters with large uncertainty ranges [Gorham 1993].…”

A Comparison Study of the Performance Assessment Probabilistic Risk Assessment and Vulnerability Assessment Methodologies.

“…SNL is the lead laboratory in the development of the PRA methods at nuclear power plants. In the NUREG/CR-4551 document series (Gorham et al, 1993), SNL reported an integrated analysis of four accident phases for an overall expression of risk for the U.S. Nuclear Regulatory Commission (NRC). Key references for PRA tools also include NUREG/CR-2300 (1983) and NUREG/ CR-6823 (2003).…”

“…Accident progression analysis investigates the core damage process both in and outside the reactor vessel and the resultant impact on the containment. Source term analysis estimates the radionuclide release associated with the accident conditions, and consequence analysis calculates the offsite consequences in terms of health effects and financial loss (Gorham et al, 1993).…”

“…For severe accidents modeled by PRA, it is not possible to impose exposure requirements. Nonetheless, given an accident scenario, PRA tools are required to describe physical phenomena and the use of probabilistic techniques to characterize uncertainties, use of expert panels to develop distributions for important phenomenological issues, and automation of the overall analysis (Gorham et al, 1993).…”