To achieve a nuclear material inventory in case of emergency

Full text: Emergency situations for nuclear materials in the relevant facilities are taken into account in the French regulations. The decree issued on 12 May 1981 on the protection and control of nuclear materials currently specifies that 'the Ministry of Industry can order a physical inventory of nuclear materials and compare it with audited records under all circumstances'. These inventories are prescribed for nuclear facilities, for example in case of potential theft, loss or diversion of nuclear materials. In such situations, operators must be able to check if all nuclear materials held are actually inside the perimeter of the facility and in the expected locations. To test the organisation implemented in an emergency, at operator and competent authority levels respectively, since 1993, ten exercises with increasing complexity have already been carried out in various types of facilities (research reactor, uranium metal processing workshop, research laboratory, reprocessing plant, etc.). They have been used to train the emergency teams, to test the procedures set up for that purpose, to check the efficiency of the operational resources (communication, measurements, etc.) and to estimate the time required to perform the various steps (activation of crisis centre, checking of physical protection devices, inventory of items and measurements). These exercises have notably shown the need to plan action sequences to improve the efficiency of the inventory taking and the importance of using seals to reduce its duration. The benefit gained from them also highlights the main items to be considered before organising such an exercise. One of the most important parameter is the choice of the scenario, that should be realistic, easily implemented and elaborated with the intention of inducing lesson learnt. After a short overview of French domestic regulations, this paper develops this item and more particularly deals with the various types of possible scenarios based on non-proliferation, malevolence or media-blackmail and the impact of the scenario choice on the development of the exercise. (author)