Accident identification in tritium processing system of international thermonuclear experimental reactor in engineering design activity

International Thermonuclear Experimental Reactor (ITER) is designed for the demonstration of the feasibility of Tokamak type fusion reactor by using 100g to 1kg of tritium. The tritium processing systems of ITER is being designed for reprocessing of plasma exhaust, clean-up of tritiated coolant water, safety systems to confine any tritium handling equipment and so on. Because of the significance of the total tritium inventory and throughput, it is necessary to perform safety analysis and emphasis the safety. It is necessary to identify the failure mode which may cause accident. In this work, the method of Failure Modes and Effect Analysis (FMEA) was applied to identify failure modes for major components of the tritium processing systems, focused on their functions. The result of FMEA clarified. The major initiating events, necessary detection system of off-normal events, issues to be discussed further and issues to be analyzed further, pointing out the necessity of further safety analysis work. (author)