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:
locate the ful* column. Analyses of internal gas composition and measurement of total gas volume are other measurements important in design verification. .Cladding examinations and tests are designed to determine physical, chemical, and mechanical changes that have occurred as a result of ther- mal, mechanical, and environmental exposure in the reactor. Metallo- graphic examinations determine microstructural changes, corrosion 1.119-2 behavior, and, for zircaloy cladding, hydride platelet orientation. Density and hardness measurements supplement the metallographic examina- tion for determining the type of physical changes that have occurred in the cladding. Chemical analyses of the cladding are useful in correlating the physical, mechanical, and corrosion behavior of the cladding. Mechan- ical property testing can include the complete spectrum of tensile tests, burst tests, bend tests, and creep and fatigue tests. Fuel pellet exami- nations can include density and dimensional determinations plus micro- structural observations. C. REGULATORY POSITION A surveillance program to directly observe the behavior of the actual fuel system as it performs in the reactor should be conducted in order to demonstrate the validity of the conclusions reached from the design evaluation. The surveillance program should include visual examination of all fuel assemblies upon discharge into the spent fuel pit and precharacteri- zation of selected fuel assemblies, with nondestructive and destructive postirradiation examinations conducted when deemed necessary. Prior to establishing the surveillance program, documentation should be prepared defining the functional characteristics of the new assemily design. The anticipated performance under all expected events and conditions should be-described. 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