Document: NRC Regulatory Guide
Document ID: 22ccfd5e-c5d8-4615-a02c-32369aa9f533
Document Type: regulatory_guide
Title: Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1930/ML19308B636.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.200
CFR Part: 
CFR Title: 

Content:
fsite power, plant transient, loss of condenser heat sink, etc. Internal Flood Flooding that results from leaks or ruptures of liquid systems (e.g., tanks, pipes, valves, pumps) originating inside the plant site boundary. Internal Fire Effects of fire that originate within the defined plant boundary. Industrial Accidents (internal) Accidents occurring offsite at a facility, or human-caused accidents occurring onsite, causing functional failure of plant SSCs. Hazards that could potentially result in an industrial accident include: DG-1362, Appendix D, Page D-2 Hazard Group/ Hazard Direct or Secondary Impact of Hazard Heavy Load Drop (internal) The uncontrolled lowering of a load to the point where contact with an underlying surface or some object stops any further decent. Onsite Hazardous Material Release (internal) An onsite release of hazardous material including, but not limited to toxic or asphyxiant gases, liquids, combustion products, or radioactivity. Such releases may be concurrent with or induce an explosion or the generation of missiles. In this context, an onsite release of radioactivity is assumed to be associated with low-level radioactive waste. Site-Generated Missiles (internal) Damage to safety-related SSCs from a missile generated internal to the plant PRA boundary from rotating turbines or other internal sources (e.g., high- pressure gas cylinders). Damage may result from a falling missile or a missile ejected directly toward safety-related SSCs (i.e., low-trajectory missiles). EXTERNAL HAZARDS External flood: An excess of water outside the plant boundary that causes functional failure to plant SSCs. Hazards that could potentially result in an external flood include: Dam Failure Flooding that results from the failure (i.e., structural collapse, severe leakage, or overtopping) of a dam that produces excess water flow past the structure. Secondary hazards resulting from a dam failure, include, but are not necessarily limited to: • Low lake or river