ISO 21613:2015 describes a method for determining chlorine and fluorine in mixed (U,Pu)O2 powders and sintered pellets. It is applicable for the analysis of samples containing 5 µg.g−1 to 50 µg.g−1 of chlorine and 2 µg.g−1 to 50 µg.g−1of fluorine. For UO2 powder and sintered pellets, refer to ISO 22875.