Document: NRC Regulatory Guide
Document ID: 99fe445b-c440-4921-ba8f-841c8f236046
Document Type: regulatory_guide
Title: Nuclear Power Plant Instrumentation for Earthquakes + HISTORY - HISTORY 09/2016 – DG-1332 , Proposed Revision 3 04/2015 – Periodic Review on Revision 2 – Revise 02/1995 – DG-1033, Third Proposed Revision 2 11/1992 – DG-1016, Second Proposed Revision 2 07/1981 – Draft MS 140-5 , First Proposed Revision 2 (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1610/ML16104A220.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.12
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CFR Title: 

Content:
actor building including adjacent foundations if they are constructed integrally with the containment foundation. cumulative absolute velocity (CAV) The time integral of absolute acceleration over the duration of the strong shaking. There is a “Standardized CAV” algorithm in EPRI TR-100082, "Standardization of the Cumulative Absolute Velocity" that ignores small- amplitude shaking and is therefore more stable; it is preferred for seismic instrumentation. This quantity has been shown to be a good indicator of the damage potential of an earthquake time history. DG-1332, Page 19 foundation input response spectra (FIRS) When the site-specific ground motion response spectra (GMRS) and the site-independent certified seismic design response spectra (CSDRS) are determined at different elevations, the site-specific GMRS need to be transferred to the base elevations of each Seismic Category I foundation. free field The free-field is defined as those locations on the ground surface or in the site soil column that are sufficiently distant from the nuclear power plant structures to be essentially unaffected by the vibration of these structures. Therefore, a time-history recorder located at the free-field records essentially the free-field ground motion. ground motion response spectra (GMRS) Site-specific ground motion response spectra characterized by horizontal and vertical response spectra determined as free-field motions on the ground surface or as free-field outcrop motions on the uppermost in-situ competent material using performance-based procedures in accordance with RG 1.208. The GMRS represents the first part of the development of the Safe Shutdown Earthquake ground motion (SSE) for a site as a characterization of the regional and local seismic hazard. The final SSE must satisfy both 10 CFR 100.23 and Appendix S, “Earthquake Engineering Criteria for Nuclear Power Plants,” to 10 CFR Part 50. nonaccessible instruments Instruments or sensors in locations that do