Document: NUREG-0800
Document ID: 39eaebb5-884c-4731-895a-8df4686b7293
Document Type: srp
Title: REGULATORY TREATMENT OF NONSAFETY SYSTEMS FOR PASSIVE
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1403/ML14035A149.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.3
CFR Part: 
CFR Title: 

Content:
ielding to permit access after an accident, redundancy for the more probable single active failures, availability of nonsafety-related electric power, and protection against more probable hazards. The standards also address realistic safety margin analysis and testing to demonstrate the systems’ capabilities to satisfy their functions. However, the ALWR URD does not include specific quantitative standards for the reliability of these systems. Appropriate levels of reliability and availability for these systems are established with the reliability assurance program (RAP) and RTNSS process. The scope, criteria, and process used to determine RTNSS for the passive plant designs are established in: 1. SECY-94-084, “Policy and Technical Issues Associated with the Regulatory Treatment of Nonsafety Systems in Passive Plant Designs,” dated March 28, 1994 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML003708068) and associated Staff Requirements Memorandum (SRM), June 30, 1994 (ADAMS Accession No. ML003708098). 2. SECY-95-132, “Policy and Technical Issues Associated with the Regulatory Treatment of Nonsafety Systems (RTNSS) in Passive Plant Designs,” dated May 22, 1995 (ADAMS Accession No. ML003708005), and associated SRM, June 28, 1995 (ADAMS Accession No. ML003708019). 3. SECY-96-128, "Policy and Key Technical Issues Pertaining to the Westinghouse AP600 Standardized Passive Reactor Design,” June 12, 1996 (ADAMS Accession No. ML003708224), and associated SRM, January 15, 1997 (ADAMS Accession No. ML003755486). SECY-94-084 and SECY-95-132 describe the scope, criteria, and process used to determine RTNSS in the passive plant designs. 19.3-3 Revision 0 – June 2014 The following five key elements make up the process: 1. The ALWR URD describes the process the designer should use to specify the reliability/availability (R/A) missions of risk-significant SSCs needed to meet regulatory requirements and to allow comparisons of these missions