This standard specifies technical terms and definitions in the field of reactor fuel elements. This standard applies to the preparation and translation of standards, technical documents, books, periodicals, teaching materials and manuals in the field of reactive fuel elements. In this standard, words in square brackets are words that can be omitted without causing confusion, and words in round brackets are additions or substitutions. This standard is arranged in alphabetical order of Chinese Pinyin, and the English index is in Appendix A (Supplement).