Risk Assessment of Radiological and Non-radiological Hazard for Accident Prevention in Decommissioning Activities

摘要

Decommissioning activities of nuclear facilities can be said that they consist of a sequence of problem solving operations, partly because there may exist working environments contaminated by radiological substances, and partly because there are few workers who experienced that kinds of decommissioning operations in the past. Therefore, not a few countries in the world have been trying to find out appropriate techniques in order to guarantee safety and efficiency of the process. In spite of that, there still exists neither domestic nor international standard since the nuclear facilities are too diverse. In this paper, a study on risk assessment technique was carried out for decommissioning of nuclear facilities with special reference to radiological- and non-radiological hazards on the premise that they should be minimized. For that purpose, general risk assessment process was introduced first, and the whole decommissioning process was modeled as a combination of work procedure for decontamination and that for dismantling. On the basis of the present stay, a practical method to develop checklist for human error prevention during decommissioning operations, and the necessity of a mathematical model for group decision making could be introduced.