1.1 This specification applies to pellets of stabilized cubic hafnium oxide used in nuclear reactors. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for informati This specification covers the properties and requirements for pellets of stabilized cubic hafnium oxide used in nuclear reactors. Hafnium oxide should consist of a stabilizing agent, the recommended of which is yttrium oxide, though others such as calc