INES 7: Major accidentImpact on People and Environment:
- Major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures.
In March 18, rating of the INES on the events in Fukushima Dai-ichi Nuclear Power Station, by the Tohoku Regional Pacific Ocean Offshore Earthquake is temporary estimated Rating 5. However, Nuclear and Industrial Safety Agency (NISA) estimated total amount of discharge from Fukushima Dai-ichi NPS, using the analytical result of the state of nuclear reactor under the cooperation of Japan Nuclear Energy Safety Organization (JNES). As a result of re-evaluation, total amount of discharged I131 is estimated at 1.3E17Bq, and Cs137 is estimated at 6.1E15Bq.