Methods for external event screening quantification: Risk Methods Integration and Evaluation Program (RMIEP) methods development

Technical Report · Wed Jul 01 04:00:00 EDT 1992

OSTI ID:10164296

Ravindra, M K; Banon, H ^[1]

---

1. NTS/Structural Mechanics Associates, Newport Beach, CA (United States)

In this report, the scoping quantification procedures for external events in probabilistic risk assessments of nuclear power plants are described. External event analysis in a PRA has three important goals; (1) the analysis should be complete in that all events are considered; (2) by following some selected screening criteria, the more significant events are identified for detailed analysis; (3) the selected events are analyzed in depth by taking into account the unique features of the events: hazard, fragility of structures and equipment, external-event initiated accident sequences, etc. Based on the above goals, external event analysis may be considered as a three-stage process: Stage I: Identification and Initial Screening of External Events; Stage II: Bounding Analysis; Stage III: Detailed Risk Analysis. In the present report, first, a review of published PRAs is given to focus on the significance and treatment of external events in full-scope PRAs. Except for seismic, flooding, fire, and extreme wind events, the contributions of other external events to plant risk have been found to be negligible. Second, scoping methods for external events not covered in detail in the NRC`s PRA Procedures Guide are provided. For this purpose, bounding analyses for transportation accidents, extreme winds and tornadoes, aircraft impacts, turbine missiles, and chemical release are described.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (United States). Div. of Safety Issue Resolution; NTS/Structural Mechanics Associates, Newport Beach, CA (United States); Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: Nuclear Regulatory Commission, Washington, DC (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 10164296
• Report Number(s): NUREG/CR--4839; SAND--87-7156; ON: TI92018159
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200
220900
99 GENERAL AND MISCELLANEOUS
990200
AIRCRAFT
CHEMICAL SPILLS
COMPONENTS AND ACCESSORIES
DISTRIBUTION FUNCTIONS
FIRES
FLOODS
MATHEMATICS AND COMPUTERS
NUCLEAR POWER PLANTS
PROBABILITY
PROJECTILES
REACTOR COMPONENTS
REACTOR SAFETY
RISK ASSESSMENT
SEISMIC EFFECTS
STATISTICAL MECHANICS
TORNADOES
WIND