This specification applies to pellets of stabilized zirconium oxide used in nuclear reactors. The chemical composition requirements such as the stabilizing additive (calcium oxide or yttrium oxide), analytical chemistry methods, impurity concentration (including hafnium, boron, gadolinium, samarium, europium, dysprosium, cobalt, silicon, iron, calcium, magnesium, aluminum, titanium, thorium, fluorine, chlorine, bromine, iodine, and hydrogen), and moisture concentration are prescribed. The nuclear grade pellets shall conform to the specified physical requirements which includes the following: physical dimensions, density, mechanical properties and test methods such as compressive test and thermal cycling test, and visual appearance such as end chips, circumferential chips, cracks, and fissures. The requirements for cleanliness before and after sampling and packaging are given.