scope:

This standard¹⁾ describes requirements for the unique identification (ID), through the lifetime, of fuel assemblies utilized in nonmobile nuclear reactor facilities. It defines the characters and proposed sequence to be used in assigning identification to fuel assemblies. Appendix A lists some internal fuel assembly ID/geometries for different reactors. Appendix B details light water reactor (LWR) fuel assembly number serialization sequencing.

This standard was developed primarily for commercial LWR fuel but may be used for any reactor fuel contained in discrete fuel assemblies that can be identified with a serial number as specified by this standard.

Additionally, this standard describes requirements for a matrix system for identification in mapping the location of fuel rods within a fuel assembly. The matrix system establishes unique x-y coordinates for each possible rod location. Experimental and research reactors are also detailed for the placement of rods, plates, and elements in a fuel assembly.

¹⁾ The current standard, ANSI/ANS-57.8-2020, is hereinafter referred to as "this standard."