Document: NRC Regulatory Guide
Document ID: a12b2f8d-d334-4fb6-8a51-8bf551a23833
Document Type: regulatory_guide
Title: Surveillance Program for New Fuel Assembly Designs
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1335/ML13350A277.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.119
CFR Part: 
CFR Title: 

Content:
bed. The rules and procedures used for design and analysis, including safety margins, should be identified as described in Section 4.2, "Fuel System Design," of Regulatory Guide 1.70, "Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants - LWR Edition." The surveillance program should be conducted on the initial core loading that uses the new fuel assembly. The initial core loading should contain two precharacterized fuel assemblies in each of at least three regions of the core. Surveillance should be conducted on approximately one-third of the initial core fuel assemblies during each of the first three refueling periods. The design verification program should include the following: 1. Precharacterization .. . . .... .... - . . . The preselected precharacterization fuel assemblies should undergo characterization to establish baseline data to be used to facili- tate the evaluation of fuel performance, dimensional changes, or any anomalies that might be evident from the subsequent surveillance program. Precharacterization should be directed at the specific parameters under- going redesign and may include the following or other applicable k examinations: 1.119-3 a. Assemblies (1) Measurement of the distance between spacers. (2) Measurement of spacing between rods. (3) Measurement of spacer-to-fuel-rod perpendicularity. b. Fuel Rods (1) Overall visual examination. (2) Measurement of length and diameter, both axial and helical profiles using profilometry. (3) Eddy current or ultrasonic tests. (4) X-ray or neutron radiography. 2. Surveillance The surveillance program should consist of a general visual inspection of all the peripheral rods as they are discharged into the spent fuel pool. Approximately one-third of the initial core fuel assem- blies should be inapected during each of the first three refueling periods. All pertinent data on the nuclear environment and plant operating history should be recorded. Key parameters such as power, coolant