INES scale

Since the World War II, there have been some nuclear and radiological events around the world produced directly or indirectly by humans. The most famous are the Chernobyl disaster in 1986 or the Fukushima nuclear disaster in 2011, but there have been many others.

In 1990, the International Atomic Energy Agency (IAEA), introduced the INES (Intertional Nuclear and Radiological Event Scale). A scale to enable fast classification and communication of nuclear accidents.

Using the INES, - that is intended to be logarithmic with each increasing level aproximately ten times as severe as the previous level, - goverments, organizations and people can easily get an idea of the severity of the event, and take actions accordingly.

The INES scale has 8 levels: level 0 for small deviations, levels 1 - 3 for indicents, and levels 4 - 7 for accidents.

During 2006-2008, the scale was extended to cover a wider range of radiological events, including the transport, storage and use of radioactive materials.

Nowadays, the INES scale is useful also for research reactors, radiaoactive waste facilities, industrial radiography, medial radiation sources, transport of radioactive materials or loss or theft of radioactive sources.

According the INES scale, both Chernobyl disaster and Fukushima nuclear disaster are level 7, but the 2020 event in Finland that the Olkiluoto reactor shutdown due to dissolved filter substances in reactor water, is a level 0.

References:

- https://en.wikipedia.org/wiki/International_Nuclear_and_Radiological_Event_Scale

- https://es.wikipedia.org/wiki/Escala_Internacional_de_Sucesos_Nucleares

- https://www-pub.iaea.org/MTCD/Publications/PDF/INES2013web.pdf