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:
ns The specific locations for instrumentation should be determined by the nuclear plant designer or applicant/licensee to obtain the most pertinent information consistent with maintaining occupational radiation exposures ALARA for the location, installation, and maintenance of seismic instrumentation. In general the following should be done: 1.3.1 Free-Field Sensors The free-field sensors should be located and installed so that they record the motion of the ground surface and so that the effects associated with surface features, buildings, and components on the recorded ground motion will be insignificant. A distance of at least one major structure dimension away from all large structures in the vicinity should be maintained where possible as recommended by the “Guidelines for Installation of Advanced National Seismic System Strong-Motion Reference Stations,” published by Consortium of Organizations for Strong-Motion Observation Systems (COSMOS) (Ref. 12). 1.3.2 In-structure Instrumentation The in-structure instrumentation should be placed at optimum locations that have been included in the building dynamic analysis so that the measured motion can be directly compared with the design in-structure response spectra and other parameters. The DG-1332, Page 8 instrumentation should not be located on a secondary structural frame member that is not modeled as a mass point in the building dynamic model. 1.3.3 ALARA Design Review A design review of the location, installation, and maintenance of proposed instrumentation for maintaining exposures ALARA should be performed by the facility in the instrumentation planning stage in accordance with RG 8.8. 1.3.4 Dose Rate Considerations Instrumentation should be placed in a location with as low a dose rate as is practical, consistent with other requirements. 1.3.5 Maintenance Considerations Instruments should be selected to require minimal maintenance and in-service inspection, as well as minimal time and numbers of personnel