Document: NUREG-0800
Document ID: 1c54f5f9-dd57-4543-a00d-1597061af2e0
Document Type: srp
Title: SEISMIC CLASSIFICATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1608/ML16084A812.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.2.1
CFR Part: 
CFR Title: 

Content:
to perform their safety functions. Also, compliance with 10 CFR Part 100, Appendix A and 10 CFR Part 50, Appendix S, requires that certain SSCs be designed to withstand the SSE and remain functional. The SSCs are those necessary to ensure: (1) the integrity of the reactor coolant pressure boundary; (2) the capability to shut down the reactor and maintain it in a safe shutdown condition; or (3) the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposures comparable to the guideline exposures of 10 CFR Part 100. a. RG 1.29 describes an acceptable method of identification and classification of SSCs important to safety that should be designed to withstand the SSE. RG 1.29 states that systems and components required for safe shutdown, including their foundations and supports, are designated as seismic Category I and should be designed to withstand the effects of the SSE and remain functional. In addition, RG 1.29 recommends that systems, other than radioactive waste management systems, that contain, or may contain, radioactive material and whose postulated failure would result in potential offsite whole body (or equivalent) doses that are more than 0.005 Sv (0.5 rem), should also be classified as seismic Category I. Conformance with RG 1.29 assures that, by designing the SSCs identified in the guide to withstand the effects of an SSE, a designed-in safety margin is provided for bringing the reactor to a safe, shutdown condition, while also reducing potential offsite doses from seismic events. b. In addition, certain system-specific regulatory guides provide information on seismic classification of portions of those systems at a more precise level of detail than is provided in the general statements in RG 1.29. RG 1.151 provides guidance for the proper seismic classification of safety-related instrumentation sensing lines used to actuate or monitor safety-related systems. 3.2.1-8 Revision 3 – July 2016 c.