Document: NRC Regulatory Guide
Document ID: 60ac4a53-3f72-4e92-9ad2-39c736cf2135
Document Type: regulatory_guide
Title: Functional Specification for Active Valve Assemblies in Systems Important to Safety in Nuclear Power Plants
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003739979.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.148
CFR Part: 
CFR Title: 

Content:
ing, and applicability of and relationship among the separate standards and (2) there should be both technical compatibility and consistent 4As defined in Section III of the Code, "construction" is an all-inclusive term comprising materials, design, fabrication, examina tion, testing, inspection, and certification required in the manufacture and installation of items. requirements for similar issues among the documents that make up the set of comprehensive requirements. Accordingly, those valve assemblies that are classified as ASME Code Class 1, 2, or 3 (Quality Groups A, B, and C, respectively, as identified in Regulatory Guide 1.26, "Quality Group Classifications and Standards for Water-, Steam-, and Radioactive-Waste-Containing Components of Nuclear Power Plants") are relatively amenable to meeting a set of comprehensive requirements. One approach to aid in providing this set of requirements would be to include the functional specification requirements of ANSI N278.1-1975 with the Design Specification requirements of NCA-3250 in Section III of the Code. Also, it appears advisable, at least for Class I, 2, and 3 valve assemblies, that the functional specification recognize and reference certain relationships such as those pertaining to the use or applicability of Section XI and Code Case N-62-2, "Internal and External Valve Items." Although the few active valves in systems important to safety that are classified as Quality Group D in Regulatory Guide 1.26 (those that use the ANSI B3 1.1.02 standard) may not have the desired specific relationship between the functional specification and the document that serves as the basis for construction (the Design Specification of ASME Code Class 1, 2, and 3 valves), there is still a need for a set of comprehensive requirements. C. REGULATORY POSITION The requirements delineated in ANSI N278.1-1975 (1) are generally acceptable to the NRC staff for functional specifications of active valve assemblies whose operability must be