Document: NUREG-0800
Document ID: 49dad160-99d7-4356-a70a-18bb6f08d141
Document Type: srp
Title: SEISMIC CLASSIFICATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1422/ML14227A643.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.2.1
CFR Part: 
CFR Title: 

Content:
audit if the information is necessary for the Commission to make its safety determination. The staff may elect to audit available design documents such as design specifications; system description and schematics or piping and instrumentation diagrams. If available, QA lists and procurement documents associated with the seismic classification of risk-significant systems and mechanical components should be made available as supporting documents for such an audit. An audit should be scheduled based on the availability of design documents and prior to the DC or COL issuance. The staff review may include an assessment of the degree of completeness of design information supporting classifications and how seismic classification is translated into design documents. The audit may also be used to support resolution of seismic classification open items identified during the review of the application. Depending on the audit plan, the scope may be limited to a review of the seismic classification process and a sampling of risk- significant systems and mechanical components to validate that the applicant has an appropriate classification process in place. 9. GDC 2 requires SSCs that are important to safety be designed to withstand earthquakes. To support compliance with GDC 2, such SSCs should be appropriately classified to ensure that they are designed to withstand earthquakes. In addition to safety-related SSCs, nonsafety-related SSCs are to be designed to withstand earthquakes if they perform an important to safety function. The extent that these nonsafety-related SSCs are to be classified and designed for earthquakes depends on the specific need to be functional or to preclude their failure, consistent with risk insights. The risk informed approach that utilizes the probabilistic risk assessment (PRA) can be utilized to supplement and enhance the deterministic approach in order to identify these nonsafety-related SSCs that are credited in the PRA. Where industry consensus