Japan’s nuclear regulators raised the severity level of the crisis at a stricken nuclear plant Tuesday to rank it on par with the 1986 Chernobyl disaster, citing the amount of radiation released in the accident.
The regulators said the rating was being raised from 5 to 7 – the highest level on an international scale overseen by the International Atomic Energy Agency. However, there was no sign of any significant change at the tsunami-stricken Fukushima Dai-ichi nuclear plant.
The new ranking signifies a “major accident” with “wider consequences” than the previous level, according to the Vienna-based IAEA.
NISA officials said one of the factors behind the decision was that the cumulative amount of radioactive particles released into the atmosphere since the incident had reached levels that apply to a Level 7 incident.
The revision was based on cross-checking and assessments of data on leaks of radioactive iodine-131 and cesium-137, said NISA spokesman Hidehiko Nishiyama.
The amount of radioactivity released might even exceed the amount emitted by Chernobyl.
– from ap.org