International Nuclear Event Scale; a scale with seven levels
proposed by the IAEO to evaluate the events occurring in nuclear installations
according to international uniform criteria, in particular with regard
to the aspect of hazards to the population. The upper levels (4 to 7)
include accidents, the lower levels (1 to 3) anomalies and incidents.
Notifiable events of no safety-related or radiological significance
according to the international scale are designated as „below
the scale“ or "Level 0". The events are evaluated according
to three overriding aspects:
"Radiological effects outside the installation",
"Radiological effects inside the installation"and
"Impairment of safeguards".
The first aspect comprises events which lead to release
of radioactive substances into the environment of the installation.
The highest level corresponds to a catastrophic accident in which health
and environmental consequences over a wide area are to be expected.
The lowest level of this aspect - Level 3 - corresponds to a very low
level of radioactivity release resulting in radiation exposure that
amounts to about one tenth of natural radiation for the most severely
affected persons outside the installation. The second aspect comprises
Levels 2 to 5 and concerns the radiological effects inside the installation,
i.e. ranging from serious damage at the reactor core to greater contaminations
within the installation and impermissible high radiation exposure of
the staff. The third aspect - assigned to Levels 0 to 3 - comprises
events in which safeguards designed to prevent the release of radioactive
substances have been impaired.
INES scale to classify events in nuclear
11 - 15 March 2018
30 September - 04 October 2018
Prague, Czech Republic