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:
nstruments should be operating during all modes of operation; including periods of plant shutdown (see Section C.3 of this guidance). Instrument operational reliability should be demonstrated prior to installation through prototype, environmental, vibratory, or historical test results, or a combination thereof. The instrumentation should be designed to perform its function satisfactorily over an appropriate range of environmental conditions anticipated at its location, including: • Vibration (maximum free-field and in-structure earthquake-induced motion as predicted by the plant designer); • Temperature (both high and low); • Moisture (humidity, rain, snow, temporary submersion due to flooding, salt drift near coastlines, etc.); DG-1332, Page 10 • Pressure (as it affects sensor noise); • Wind (as it may affect physical integrity of the system components as well as seismic noise); • Sun (as it affects short-term thermal changes and long-term material degradation); • Radio frequency interference (both from external and internal sources); and • Magnetic interference from external sources. • Radiation throughout the plant’s design range for instrument locations. 4.8 Frequency Range The instrumentation and recorder frequency ranges given in Sections 4.11 through 4.13 are typical. For some applications higher or lower ranges might be more appropriate. The ranges selected should be consistent with the vibration characteristics of the supporting structure and equipment and the function of the instrument. 4.9 Calibration Time-history recorders should have capability for in-place functional testing that can be recorded as a permanent part of the acquired information. 4.10 Time-History Recorder The components of the time history recorder (acceleration sensor, recorder, seismic trigger) may be assembled in a self-contained unit or may be separately located. Characteristics of an acceleration sensor, recorder and seismic trigger are defined below in sections