[en] There are a number of features in the method of criticality safety analysis and evaluation adopted in the original draft of this Handbook. The representative matters of them are shown. The original draft of this Handbook is bascially composed of three parts, that is, the part on the fundamental way of thinking on criticality safety management, the part on criticality safety analysis and evaluation, and the part on the requirement, management system and the matters to which attention should be paid for equipment, system, facility and machinery, which are demanded for maintaining criticality safety. As to the base of the criticality safety evaluation method described in this original draft, the 'Report of the results of criticality safety analysis data and program preparation works' shall be referred to, and as for the detailed data used for the safety analysis and evaluation, the 'Collection of data for Criticality Safety Handbook' attached to this original draft shall be referred to. This is the summary of the accomplishment of the Criticality Handbook Expert Committee for four years, but it is desirable to revise this hereafter as the research and engineering advance. The method and numerical values described in this original draft are sufficiently safe. (Kako, I.)