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:
ntake 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 period of below-average precipitation in a given region, thereby depleting the water supply needed for the various water-cooling functions to the facility. Dust Storm Persistent heavy winds transporting sand or dust that infiltrate SSCs at or in the plant analyzed area causing functional failure. DG-1362, Appendix D, Page D-6 Hazard Group/ Hazard Direct or Secondary Impact of Hazard Fog Low lying water vapor in form of cloud or obscuring haze of atmospheric dust or smoke resulting in impeded visibility that could result in transportation accident. Hail A shower of ice or hard snow that could result in transportation accidents or directly causing dynamic loading or freezing conditions as a result of ice coverage. Ice Blockage Flooding due to downstream blockages of ice on a river. Secondary hazards resulting from an ice blockage, include, but are not necessarily limited to: • River and stream overflow Lightning Effects on SSCs due to a sudden electrical discharge from a cloud to the ground or Earth-bound object. Snow The accumulation of snow resulting could result in transportation accidents, or directly cause dynamic loading or freezing conditions as a result of snow cover. Extraterrestrial Object Impacts A release of energy due to the impact of a space object such as a meteoroid, comet, or human-caused satellite fall with the Earth’s atmosphere, a direct impact with the Earth’s surface, or a combination of these effects. This hazard is analyzed with respect to direct impacts of an SSC and indirect impact effects such as thermal effects (e.g., radiative heat transfer), overpressure effects, seismic effects, and the effects of ejecta resulting from a ground strike. Table D-2. List of Hazard Causes and Conditions Combustion/fire – resulting in burning, release of