Hazard Assessment of the International Fusion Materials Irradiation Facility

A neutron irradiation facility is planned as International Fusion Materials Irradiation Facility (IFMIF) under the collaborative program of International Energy Agency (IEA) Implementing Agreement for a Program of Research and Development on Fusion Materials. IFMIF facility is aimed to provide an intense neutron source (peaked at 14 MeV) by a high current deuteron linear accelerator and a high-speed lithium flow target for testing candidate materials for fusion. Liquid lithium is being circulated through a loop and is kept at a temperature above its freezing point. IFMIF facility is conveniently subdivided in the following subsystem facilities: - Test facilities, which expose, package and examine material specimen; - Accelerator facilities, which produce accelerated deuterons; - Target facilities, which produce a flowing stream of lithium to convert the deuterons to neutrons In the frame of the design phase called Key Element technology Phase (KEP), jointly performed by an international team to analyse the most important risk factors, safety assessment of the whole plant has been required in order to identify the hazards associated with the plant operation (ref.1). A hazard identification used qualitative method, like Failure Mode and Effect Analysis (FMEA), has been considered the most suitable technique to accomplish the task, providing, in addition, important input to more detailed quantitative studies aimed at the final plant safety assessment (e.g. fault trees and event trees).