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
CFR Part: 
CFR Title: 

Content:
ted with the time history recorder nearest to the free-field ground station. 6.2 Spurious Triggering Spurious triggering should be avoided. 6.3 Threshold Ground Motion Acceleration The seismic trigger mechanisms of the time history recorder should be set for a threshold ground acceleration of not more than 0.01g. DG-1332, Page 14 7. Remote Indication Triggering of the free-field, downhole, or any foundation-level time-history recorder should be annunciated in the control room. If there is more than one control room at the site, annunciation should be provided to each control room. 8. Accompanying Materials The calibration standards, computer software, record analyzers, etc., required to process the records from the seismic instruments should be on hand at the site and at other locations, if any, where records will be processed so that the records can be processed within the required time period of 4 hours after an earthquake. 9. Maintenance 9.1 General The purpose of the maintenance program is to ensure that the seismic equipment will perform as required. Maintenance should be preplanned and performed in accordance with documented instructions or drawings appropriate to the instrument. The technical, testing, and administrative portions of the maintenance procedures should be defined and documented before plant startup. As stated in Section C.3 of this guidance, the maintenance and repair procedures should provide for keeping the maximum number of instruments in service during plant operation and shutdown. The maintenance program should address technical, testing, and administrative procedures. After initial installation and each servicing of the free-field time history recorder, a response spectrum and a cumulative absolute velocity (CAV) should be calculated using a standard input signal or suitable time history (e.g., the October 1987 Whittier, California, earthquake). Information relative to CAV data can be found in Electric Power Research Institute (EPRI)