Areva - Reference Document 2016

GLOSSARIES 1. Technical glossary

> Hulls Pieces about 3 centimeters long produced by the shearing of the metal cladding (fuel rods) that had contained nuclear reactor fuel. > IAEA (International Atomic Energy Agency) International organization under the aegis of the United Nations (UN) whose role is to promote the peaceful use of nuclear energy and to verify that nuclear materials in users’ possession are not diverted to military uses. > INES (International Nuclear and Radiological Event Scale) International scale designed by the IAEA to facilitate communication about nuclear events. It provides comparative elements that can be used to assess the seriousness of an event. The scale ranges from level 0 (deviation with no safety significance) to level 7 (major accident with considerable health and environmental consequences). Three criteria apply in the application of the INES: Established near nuclear sites falling within the realm of National Defense whose mission is to inform the public on the health and environmental impacts of the nuclear operations. > In situ recovery Mining method consisting of recovering a mineral by injecting an acidic or alkaline oxidizing solution directly into the geologic stratum containing the mineral, thus dissolving it. The term “in situ leaching” is also used. > Instrumentation and control system Combination of electrical and electronic systems used for control, i.e. to perform measurements, operate control systems, and ensure the operating safety of a nuclear power plant or any other complex industrial system. > Internal emergency management plan Describes the organization, response methods and resources to cope with emergency situations (incident or accident) to protect personnel, the public and the environment from radiation, and to maintain the safety of the regulated nuclear facility. > Internal operation plan ( Plan d’opération interne , POI) Describes organizational procedures and resources available at an industrial site to minimize the consequences of a potentially major disaster for people, property and the environment. It may be required by regulation, pursuant to article R.512-29 of the French Environmental Code (environmentally-regulated facility with AS classification, any other facility following a prefectural decision, and certain special facilities such as storage depots of more than 50,000 m 2 ). p offsite radioactive releases; p the consequences inside the installation (damages or personnel injuries); p degradation of defense in depth. > Information commission

> Ionizing radiation Flux of electromagnetic waves (radio waves, light waves, ultraviolet or X rays, cosmic rays, etc.), of particles of matter (electrons, protons, neutrons), or of a group of such particles. The flux carries energy which rises with the wave frequency or with the particle speed. The effect of radiation on objects and living organisms is to strip electrons from the atoms that make up their matter (whether living or inert), leaving ionized atoms in their wake, which carry electrical charges, hence the generic name of “ionizing” radiation. > IPCC (Intergovernmental Panel on Climate Change) Created in 1988 at the initiative of the G7 countries and made up of UN experts, the IPCC is now part of the World Meteorological Organization in the framework of the UN Environment Program. Its role is to assess scientific, technical and socioeconomic information concerning the risk of human-induced climate change. In this regard, it publishes several reports that forecast, among other things, an average increase in global temperatures in one century. > Irradiation Exposure of an organism or an organ to radiation when the radiation source is outside the organism. > IRSN ( Institut de radioprotection et de sûreté nucléaire ) The French institute for radiation protection and nuclear safety, a public industrial and commercial agency whose mission, in particular, is to conduct research and assessments in the fields of nuclear safety, protection of people and the environment from ionizing radiation, and nuclear materials safeguards. IRSN provides technical support to the ASN and the HFDS. > ISO standards From the International Standards Organization. The ISO series 9000 standards set organizational andmanagement system requirements for quality to demonstrate the conformity of a product or service, in particular to customer requirements. The ISO series 14000 standards set requirements for the environmental organization and management system designed to prevent pollution and reduce the environmental effects of an activity. > Isotopes Nuclides whose atoms have the same number of protons in their nuclei, but a different number of neutrons. For example, three main types of uranium isotopes are found in nature: 234 U (92 protons, 92 electrons, 142 neutrons), 235 U (92 protons, 92 electrons, 143 neutrons), and 238 U (92 protons, 92 electrons, 146 neutrons). All of the isotopes of a given element have the same chemical properties, but different physical properties (mass in particular). > Isotopic assay Ratio of the number of atoms of a given isotope of an element to the total number of atoms of that element contained in matter. Isotopic assay is expressed as a percentage. > Isotopic separation cascade Arrangement of separative elements (“stages”), which are interconnected to increase the separative effect of a unit element. The gaseous diffusion and centrifugation enrichment processes separate uranium-238 and uranium-235 by exploiting the difference in mass between those isotopes. Because the separative potential of these processes is low to very low, the basic step must be repeated a large number of times in a cascade to achieve the desired level of enrichment. These elementary stages take place in diffusers or centrifuges, which together form a cascade.

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2016 AREVA REFERENCE DOCUMENT