Document: NRC Regulatory Guide
Document ID: 1d715751-9321-4481-a46f-4ff802a5efe0
Document Type: regulatory_guide
Title: Service Limits and Loading Combinations for Class 1 Linear-Type Supports + HISTORY – HISTORY 10/2006 – DG-1168 , Proposed Revision 2
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0630/ML063000449.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.124
CFR Part: 
CFR Title: 

Content:
lling criterion. However, if a particular plant condition does not require the function of a component support, the stresses or loads resulting from the loading combinations under that plant condition do not need to satisfy the design limits for the plant condition. Definitions Design Condition. The loading condition defined by NF-3112 of Section III of the ASME Boiler and Pressure Vessel Code. Plant Conditions. Operating conditions of the plant categorized as normal, upset, emergency, and faulted plant conditions. Normal Plant Conditions. Those operating conditions that occur in the course of system startup, operation, hot standby, refueling, and shutdown, with the exception of upset, emergency, or faulted plant conditions. Upset Plant Conditions. Those deviations from the normal plant condition that have a high probability of occurrence. Emergency Plant Conditions. Those operating conditions that have a low probability of occurrence. Faulted Plant Conditions. Those operating conditions associated with postulated events of extremely low probability. Service Limits. Stress limits for the design of component supports, defined by Subsection NF of Section III of the ASME Boiler and Pressure Vessel Code. Levels of Service Limits. Four levels of service limits — A, B, C, and D — defined by Section III of the ASME Boiler and Pressure Vessel Code for the design of loadings associated with different plant conditions for components and component supports in nuclear power plants. Operating-Basis Earthquake (OBE). Seismic event defined in Appendix A to 10 CFR Part 100, “Reactor Site Criteria.” Safe-Shutdown Earthquake (SSE). Seismic event defined in Appendix A to 10 CFR Part 100. Specified Seismic Events. Operating-basis earthquake (OBE) and safe-shutdown earthquake (SSE), as defined above. System Mechanical Loadings. The static and dynamic loadings developed by the system operating parameters—including deadweight, pressure, and other external loadings—and effects