Document: NUREG-0800
Document ID: 711747d3-335d-42bb-b30d-17cc0f6162ed
Document Type: srp
Title: SEISMIC INSTRUMENTATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340571.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.7.4
CFR Part: 
CFR Title: 

Content:
tures and equipment with calculated responses determined from dynamic analysis. First, the time history records are digitized and corrected for time signal variations and baseline variations. The time history records from the triaxial sensors located in the free field or at the foundation of the containment building are used to calculate response spectra at appropriate critical damping values. The response spectra thus obtained, or the response spectra from the response spectrum recorder, are compared with the design response spectra. In addition, the time history records from the free field triaxial sensor are used as input ground motion for the reactor building dynamic model, including soil where applicable. Amplified response spectra are then calculated at the locations of the other sensors in the reactor building for comparison and correlation with the response spectra directly measured. Structural responses and ampli- fied response spectra are calculated using the free field time history records with the dynamic model for comparison with the original design and analysis parameters. This comparison permits evaluation of seismic effects on structures and equipment and forms the basis for remodeling, detailed analyses, and physical inspection. 5. Inservice Surveillance Each of the seismic instruments shall be demonstrated operable by the performance of the channel check, channel calibration, and channel func- tional test operations at the intervals specified in Table 3.7.4-2. III. REVIEW PROCEDURES For each area of review, the following review procedure is followed. The reviewer will select and emphasize material from the procedures given below, as may be appropriate for a particular case. 1. Comparison with Regulatory Guide 1.12 The seismic instrumentation program is checked to assure that the instru- mentation is in accordance with the guidelines of Regulatory Guide 1.12. 3.7.4-4 Rev. 1 - July 1981 Any differences between the proposed and the guide seismic