ISO 21484:2017描述了一种测定混合铀-钚氧化物(U，Pu)O2±X芯块中氧与金属(O/M)比率的方法。以下段落中给出的参数与在对应于1.98至2.01的O/M比范围内的粒料相关。如果O/M比的期望值在该范围之外，则就参数而言，调整文献中描述的方法。

ISO 21484:2017 describes a method for determining the Oxygen-to-Metal (O/M) ratio in mixed uranium-plutonium oxide (U,Pu)O_{2 ± X} pellets. The parameters given in the following paragraphs are relevant for pellets within a range of O/M ratio corresponding to 1,98 to 2,01. The method described in the document is adapted, with regard to the parameters, if the expected values of O/M ratio are outside the range.