Document: NRC Regulatory Guide
Document ID: 4f130c35-25dc-4950-b437-3801efdab5f6
Document Type: regulatory_guide
Title: Protection Against Extreme Wind Events and Missiles for Nuclear Power Plants (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1435/ML14356A107.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.117
CFR Part: 
CFR Title: 

Content:
the gaseous radwaste treatment system whose failure caused by tornado or hurricane effects could result in potential offsite exposures in excess of the criterion given in subitem (3) of the regulatory position. 9. systems or portions of systems that are required for monitoring, actuating, and operating protected portions of systems listed in items 4, 6, 7, and 13. 10. all electric and mechanical devices and circuitry between the process sensors and the input terminals of the actuator systems involved in generating signals that initiate protective actions by tornado-protected portions of systems listed in items 4, 6, 7, and 13. 4 As defined in Title 10 of the Code of Federal Regulations 50.2, “Definitions.” 5 The system boundary includes those portions of the system required to accomplish the specified safety function and connecting piping up to and including the first valve (including a safety or relief valve). This is either normally closed or capable of automatic closure when the safe function is required. 6 Alternatively, the main steam system, up to and including a second isolation valve such as a redundant series main steam isolation valve, or a turbine stop valve, may be protected. App. A to DG-1313, Page A-2 11. those portions of the long-term emergency core cooling system that would be required to maintain the plant in a safe condition for an extended time after a loss-of-coolant accident. 12. primary reactor containment and other structures, such as the control room building and auxiliary building, to the extent that they not collapse, allow perforation by missiles, or generation of secondary missiles, any of which could cause unacceptable damage to protected items. However, the primary containment need not necessarily maintain its leak-tight integrity. 13. the Class 1E electric systems and necessary support systems, including the auxiliary systems for the onsite electric power supplies, that provide the emergency electric power needed for the