ASN Report 2018

1.2.3  –  Industrial ionisation installations Industrial ionisation facilities, called irradiators, use the gamma rays emitted by sealed sources of cobalt-60 to irradiate targets in the irradiation cells. These irradiation cells are designed with particularly thick walls and windows, to protect the operators against the ionising radiation. The sealed sources are either placed in the lowered position, stored in a pool under a layer of water which protects the workers, or are placed in the raised position to irradiate the target item. Personnel exposure to ionising radiation is thus the primary risk in these facilities. The main applications of irradiators are to sterilise medical equipment, agri-food products and pharmaceutical raw materials. Irradiators can also be used to study the behaviour of materials under ionising radiation, notably to qualify materials for the nuclear industry. These irradiators are used by: ∙ ∙ the Ionisos Group, which operates three facilities located in Dagneux (BNI 68), Pouzauges (BNI 146) and Sablé-sur-Sarthe (BNI 154); ∙ ∙ the Steris group, which operates the Gammaster (BNI 147) and Gammatec (BNI 170) facilities in Marseille and Marcoule; ∙ ∙ CEA, which operates the Poséidon irradiator (BNI 77) on the Saclay site. 1.3  ̶  Materials storage facilities The materials storage facilities operated by CEA are primarily devoted to the conservation of non-irradiated (or slightly irradiated) uranium and plutonium-bearing fissile materials from other CEA facilities. This enables the laboratories (Atalante, Lefca, etc.) to be supplied according to the needs of the experiments being conducted. More recently, they have become a temporary storage solution for the fissile materials which were present in facilities that are now shutdown, such as the research reactors (ÉOLE, Minerve, Osiris, Masurca, etc.). • Principles and safety issues The main challenges inherent in these facilities are to prevent the dispersal of radioactive substances and to control the chain reaction (criticality). The safety of these facilities is based on a series of static physical barriers (walls and doors of rooms and buildings) to prevent the dispersal of radioactive substances. When operations are carried out on these substances, static confinement is also provided by the equipment (glovebox, shielded cell) in which these operations are performed. This static confinement is supplemented by dynamic confinement consisting on the one hand of a cascade of negative pressure environments between the rooms where there is a risk of radioactive substance dissemination and, on the other, filtration of the gaseous releases into the environment. The chain reaction is controlled by strict instructions regarding the handling, storage and monitoring of the materials being stored. • Dedicated storage facilities The Magenta facility (BNI 169), commissioned in 2011 and operated by the CEA on its Cadarache site, is dedicated to the storage of non-irradiated fissile material and the non- destructive characterisation of the nuclear materials received. It is more particularly replacing the Central Fissile Material Warehouse (MCMF, BNI 53), which was finally shut down at the end of 2017 and is now empty. • Materials storage areas in BNIs Other radioactive material storage areas, located within a BNI, are authorised to store radioactive materials on the site, but in quantities far lower than those stored in Magenta. This is for example the case with BNI 55, called STAR, which stores spent fuels and fuels irradiated following reprocessing and/or conditioning. 1 : Shielded cells 2 : Transfer vehicles 3 : Shafts Active Fuel Examination Laboratory - LECA ASN report on the state of nuclear safety and radiation protection in France in 2018  331 12 – NUCLEAR RESEARCH AND MISCELLANEOUS INDUSTRIAL FACILITIES 12