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:
ease of radioactivity is assumed to be associated with low- level radioactive waste. Pipeline Accident A release of hazardous material, a release of combustion products, an explosion, or generation of missiles due to an accident involving the rupture of a pipeline carrying hazardous materials. Site-Generated Missiles (external) Damage to safety-related SSCs from a missile generated external to the plant PRA boundary from rotating turbines or other external 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). Transportation Accidents Accidents involving transportation resulting in collision with SSCs, a release of hazardous materials or combustion products, an explosion, or a generation of missiles, causing functional failure of SSCs. Hazards that could potentially result in transportation accidents include: Aircraft impact An aircraft (either a portion of [e.g., missile] or the entire aircraft) that collides either directly or indirectly (i.e., skidding impact with one or more SSCs at or in the plant analyzed area causing functional failure. Secondary hazards resulting from an aircraft impact, include, but are not necessarily limited to: • fire Vehicle, railcar, marine accident An accident of a vehicle, railcar or ship (boat) that involves a collision, derailment, potentially resulting in fire, explosions, toxic releases, missiles, etc. Other Natural Phenomena An observable geologic or meteorological event that causes functional failure of SSCs. Hazards that could potentially result in other natural phenomena include: Biological Events Accumulation or deposition of vegetation or organisms (e.g., zebra mussels, clams, fish, algae, etc.) on an intake structure or internal to a system that uses raw cooling water from a source of surface water, and therefore, causing its functional failure. Drought A shortage of surface water supplies due to a