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:
ll 19.3-5 Revision 0 – June 2014 interact with staff responsible for review of the applicant’s PRA to gain an understanding of the R/A mission of SSCs within their review scope as characterized in the PRA. Reviewers responsible for review of systems and components relied upon to ensure long-term safety in the period beginning 72 hours after a design basis event and lasting the following 4 days (hereafter referred to as the “Post-72 hour period”) and to address seismic events, i.e., RTNSS “B” SSCs, will interact with reviewers responsible for review of structures that house those systems and components to reach a finding regarding the ability of RTNSS “B” SSCs to withstand seismic events as severe as the design basis safe shutdown earthquake (SSE). Availability controls (ACs) are a form of regulatory oversight for the availability of nonsafety- related SSCs in the scope of RTNSS. ACs are established in a manner similar to TS and include AC LCO, applicability specifications, action statements with completion times, surveillance requirements (ACSR) and frequencies. ACs are submitted to the NRC for review in the form of the Availability Controls Manual (ACM). The review of ACM is led by the organization responsible for the review of technical specifications in Chapter 16 of the Final Safety Analysis Report (FSAR). The staff responsible for review of the applicant’s PRA and staff responsible for review of specific SSC functions support the review of the ACM in the following ways: 1. Assuring that treatment of RTNSS SSCs in the ACM is commensurate with the assumptions in the PRA. 2. Confirming that, at a minimum, ACs have been included in the ACM for RTNSS “B” SSCs. 3. Verifying the adequacy of the ACSR. II. ACCEPTANCE CRITERIA Background Requirements Acceptance criteria are based on meeting Commission policy and the relevant requirements of the following Commission regulations: 1. 10 CFR 50.36(c)(2)(ii)(D) – TS limiting condition for operation of