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International Nuclear Event Scale

 

International Nuclear Event Scale

The International Nuclear Event Scale (INES) is used by GNPS/LNPS to classify an event occurred at the plants in accordance with its safety significant to facilitate better understanding of the event by the media and public. The INES is designed by an international group of experts convened jointly by the International Atomic Energy Agency (IAEA) and the Nuclear Energy Agency (NEA) of the Organisation for Economic Co-Operation and Development (OECD). The use of INES is monitored by the IAEA. In practice, a provisional rating may be given to an event shortly after its occurrence with confirmation at a later date. It is also possible that an event may need to be re-classified later as a result of further analysis or information. The Chernobyl and Three Mile Island accidents were classified at Level 7 and Level 5 respectively under the INES scale.

 

International Nuclear Event Scale

ACCIDENT

7

Major Accident

6

Serious Accident

 

5

Accident with off-site risk

4

Accident without significant off-site risk

 
INCIDENT

3

Serious Incident

 

2

Incident

 

1

Anomaly

 
DEVIATION

0

Below Scale
No safety significance

 

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