Methodology used in the integrated assessment of PIUS-600 safety

摘要

The revolutionary reactor design, PIUS-600 as described in the Preliminary Safety Analysis Report (PSID) was subject to analyses consisting of Failure Modes. Effects and Criticality Analysis (FMECA), Hazards and Operability (HAZOP) analysis, and conventional engineering review of the stress, neutronics, thermal hydraulics, and corrosion. These results were integrated in the PIUS Intermediate Table (PIT) from which accident initiators and mitigators were identified and categorized into seven estimated frequency intervals. Accident consequences were classified as: CC-1, minor radiological release, CC-2, clad release, CC-3, major release. The systems were analyzed using event sequence diagrams (ESDs) and event trees (ETs). The resulting accident sequences of the ET, were categorized into Event conditions (ECs) based on initiator frequency and combinations of failures. System interactions were considered in the FMECAs, ESDs, ETs and in an interaction table that also identified system safety classifications.