Document: NUREG-0800
Document ID: dc63e8aa-2a74-4078-9e19-9a26ed1b4d8c
Document Type: srp
Title: Revision 6 – July 2012
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1105/ML110550791.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
ty and Defense-in-Depth Issues Interim Staff Guidance,” Revision 2. This ISG was developed with extensive review of D3 issues including both internal review within the NRC and external input through public meetings with representatives from industry, vendors, and the general public. Further, adjustments to BTP 7-19 were made in response to public comments on Revision 6. The technical changes are incorporated in Revision 6, dated April 2012. The following provides a more detailed description of changes to specific sections: A. Background The introduction was edited to indicate that BTP 7-19 addresses software common-cause failure, which is referred to as simply “CCF” in this document. The last sentence in the second paragraph beginning with, “SECY-91-292 and SECY-93-087 did not address…,” was deleted as not necessary in the introduction. 1. Regulatory Basis The Regulatory Basis section was expanded with the addition of specific listing of Clauses 6.2 and 7.2 of IEEE Std. 603-1991, and 10 CFR Part 52. The Regulatory Basis section was further expanded with the addition of regulations providing guideline values for fission product releases from NPPs including 10 CFR Part 100, 10 CFR 50.67, 10 CFR 50.34(a)(1)(ii)(D), 10 CFR 52.47(a)(2)(iv), 10 CFR 52.79(a)(1)(vi), 10 CFR 52.137(a)(2)(iv), and 10 CFR 52.157(d). 2. Relevant Guidance The Relevant Guidance section was expanded with the addition of IEEE Std. 379-2000 (Clause 5.5), Regulatory Guide (RG) 1.62, and NUREG-0800, SRP Section 7.8. 3. Purpose The Purpose section was modified to state that the NRC position on D3 for I&C systems applies to both software-based and software-logic-based protection systems. Revision 6 – July 2012 BTP 7-19-25 B. Branch Technical Position 1. Introduction To accommodate the incorporation of guidance from DI&C-ISG-02, Revision 2, the outline format was expanded. Section 1.1 was added to collect and organize an improved description of the Echelons of Defense. Section 1.2 was added