[en] Items safety classifications which is simple and reasonable, not only can improve the safety of facilities, but also can narrow differences between the reviewers and operators, and reduce workload of the operator and designer's. This paper analyses the usage of nuclear safety functions method for safety classification of items for nuclear power plant, and the adoption of dosage guidelines to safety classification of items for spent fuel reprocessing facility, and then proposes a method of radioactive materials pack capacity to classify the safety of items for the nuclear fuel cycle facilities. Using the 'unmitigated release' accident analysis method, the dose criteria of radiochemical safety 1 (250 mSv) and radiochemical safety 2 (5 mSv) are able to be translated into radioactive material package capacity criteria. (authors)