INES

INES - The International Nuclear and Radiological Event Scale - is a tool for promptly communicating to the public in consistent terms the safety significance of reported nuclear and radiological incidents and accidents, excluding naturally occurring phenomena such as Radon. The scale can be applied to any event associated with nuclear facilities, as well as the transport, storage and use of radioactive material and radiation sources.

The primary purpose of the INES Scale is to facilitate communication and understanding between the technical community, the media and the public on the safety significance of events. It covers a wide spectrum of practices, including industrial use such as radiography, use of radiation sources in hospitals, operations at nuclear facilities, and transport of radioactive material. Events are classified on the scale at seven levels: Levels 4–7 are termed “accidents” and Levels 1–3 “incidents”. Events without safety significance are termed “deviations” and are classified below scale at Level 0.

The scale was designed by an international group of experts first convened jointly in 1989 by the IAEA and the Nuclear Energy Agency of the Organization for Economic Co-operation and Development (OECD/NEA). Since then, the IAEA has managed its development in cooperation with the OECD/NEA and with the support of more than 60 designated INES national officers that officially represent the INES Member States in biennial technical meetings.

Initially the scale was applied to classify events at nuclear power plants. More recently, it has been extended and adapted further to meet the growing need for communication of the significance of all events associated with the transport, storage and use of radio-active material and radiation sources.

The current version of the INES User’s Manual (2008 Edition) is designed to facilitate the task of those who are required to rate the safety significance of events using the scale. It includes additional guidance and clarifications, and provides examples and comments on the continued use of INES. With this new edition, it is anticipated that INES will be widely used by Member States and become the worldwide scale for putting into proper perspective the safety significance of any event associated with the transport, storage and use of radioactive material and radiation sources, whether or not the event occurs at a facility.

INES leaflet (57 kb)

INES User's Manual 2008 Edition

For further information please contact the INES contact point



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