Document: NUREG-0800
Document ID: 62485d6f-6b2a-4360-acb5-f874d2adc406
Document Type: srp
Title: PIPING SYSTEMS AND COMPONENTS - INSPECTIONS, TESTS,
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1808/ML18088A069.pdf
Revision Date: 2023-06
Chapter: 14
Section ID: 14.3.3
CFR Part: 
CFR Title: 

Content:
he ASME BPV Code class welds are included in Tier 1 because ASME BPV Code, Section III, is referenced in 10 CFR 50.55a, which requires nuclear power plant components classified as Quality Groups A, B, and C to meet ASME BPV Code Class 1, 2, or 3 requirements, respectively. Each system description should include a functional drawing that shows the boundaries of the ASME BPV Code classification. The integrity of the pressure boundary is required to be maintained because it is directly involved in preventing or mitigating an accident or event under the defense-in-depth principle. ASME BPV Code Class 1, 2, or 3 pipe support welds are indirectly addressed within the scope of Tier 1, as they are reviewed as part of the ASME BPV Code Data Report generated for each system, but they do not need their own specific reference within Tier 1. The integrity of the pressure boundary in the plant will be ensured, in part, through a verification of the welding quality. This verification is performed as a 14.3.3−11 Draft Revision 1 – September 2018 part of the ASME BPV Code, Section III, Data Report ITAAC of each specific as- built system. The acceptance criteria for the welds are the ASME BPV Code, Section III, weld examination requirements. The specific weld examination requirements for a particular ASME BPV Code Class 1, 2, or 3 component and weld type are tabulated in the DCD, Tier 2. The specific weld examination requirements are considered Tier 2 because they could change depending on future revisions to the ASME BPV Code, Section III requirements. Other welding activities (non-ASME BPV Code) include: i. Pressure-retaining welds other than ASME BPV Code, Section III, welds, ii. Structural and building steel welds, iii. Electrical cable tray and conduit support welds, iv. Heating, ventilation, and air-conditioning support welds, and v. Refueling cavity and spent fuel pool liner welds. These other types of welding are included in the DCD Tier 2 scope. Tier 2 describes the