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
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CFR Title: 

Content:
ot doing so (RTNSS “C”). 7. The staff verifies that the applicant included any nonsafety-related SSCs credited in meeting the Commission’s containment performance goals in the scope of the RTNSS program (RTNSS “D”). The goals are: a. The containment should maintain its role as a reliable, leak-tight barrier by ensuring that containment stresses do not exceed American Society of Mechanical Engineers service level C limits for a minimum period of 24 hours following the onset of core damage, and that following this 24-hour period the containment should continue to provide a barrier against the uncontrolled release of fission products. b. The conditional containment failure probability determined from the Level II PRA is less than or equal to 0.1. 8. The staff reviews the applicant’s evaluation of the potential for adverse interaction between passive safety-related and active nonsafety-related systems and assures that any nonsafety-related design features or functional capabilities relied upon to prevent nonsafety-related systems from adversely impacting a safety function have been included in the scope of RTNSS (RTNSS “E”). 2 An SSC failure that is a dominant contributor to an initiating event is significant if the initiating event contributes 10 percent or more to at-power or shutdown internal events CDF. 19.3-11 Revision 0 – June 2014 Area of Review – Functional Design of RTNSS SSCs 1. The staff reviews the design of SSCs to assure that the acceptance criteria listed in Section II have been satisfied. Review is limited to those functions of the SSC needed to assure that specified R/A missions can be achieved. Area of Review – Focused PRA Sensitivity Studies 1. The organization responsible for review of the applicant’s PRA reviews the focused PRA using guidance in SRP 19.0 to assure that acceptance criteria in Section II of this SRP are satisfied. 2. The staff responsible for the review of the applicant’s PRA reviews the mission statements