This document specifies a method which covers the determination of Gd₂O₃ content in UO₂ fuel pellets, by X-ray fluorescence spectrometry.

Either wave dispersion X-ray fluorescence (WD-XRF) or energy dispersion X-ray fluorescence (ED-XRF) is applicable, however, this document states a method by using WD-XRF using Gd Lα-line.

This method has been tested for mass fractions of from 2 % to 10 % Gd₂O₃.