Document: NRC Regulatory Guide
Document ID: cdc706d5-60ed-40a4-b55a-9771904107a7
Document Type: regulatory_guide
Title: Seismic Qualification of Electric and Mechanical Equipment for Nuclear Power Plants (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1809/ML18093A675.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.100
CFR Part: 
CFR Title: 

Content:
f fractional peak cycles equivalent to the maximum peak cycles for five one-half SSE events, in accordance with IEEE Std 344-2013, Annex D, when such events are followed by one full SSE event. This is discussed in SECY-93-087, “Policy, Technical, and Licensing Issues Pertaining to Evolutionary and Advanced Light-Water Reactor (ALWR) Designs,” dated April 2, 1993 (Ref. 34). For other reactors, the staff will review the seismic qualification based on the OBE level in accordance with the design basis. i. The damping values used in the analysis should be in accordance with the damping values for mechanical and electrical components listed in RG 1.61, “Damping Values for Seismic Design of Nuclear Power Plants” (Ref. 35), or as approved in the plant’s design basis. DG-1328, Page 12 1.1.2 Specific NRC Staff Positions The NRC staff has the following specific positions on IEEE Std 344-2013, including exceptions and clarifications: a. Clause 10.2.3.1 and Clause 10.3.3.1 (Earthquake and Test Experience Data—Attributes of Equipment Class) The NRC staff will review the attributes of the equipment for establishing the inclusion rules that constitute the reference equipment class for earthquake or test experience, as described in Clause 10.2.3.1 or Clause 10.3.3.1, respectively, to determine the acceptability of similarity arguments to define a reference equipment class. The licensee or applicant should address fatigue failure at low-cycle loads. Earthquake experience data or test data are needed to demonstrate that all electrical equipment in the reference equipment class, including the enclosed or attached devices or subassemblies, performed successfully (structural integrity and specified functionality) under the equivalent of five OBE and one SSE loadings or the alternative described in Regulatory Position C.1.1.1.h for plants that are not required to evaluate an OBE. b. Clause 10.2.3.3 (Earthquake Experience Data—Reference Equipment Class Functionality)