5
INES N/A INES 0 INES 1 INES 2 INES 3 INES 4 INES 5 INES 6 INES 7 |
INES 5: Accident with wider consequences
Impact on People and Environment:- Limited release of radioactive material likely to require mplementation of some planned countermeasures.
- Several deaths from radiation.
- Severe damage to reactor core.
- Release of large quantities of radioactive material within an installation with a high probability of significant public exposure. This could arise from a major criticality accident or fire.
 INES 5 |
The core damage by loss of all cooling function due to the big tsunami. |
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 1.3*10^17Bq, and Cs137 is estimated at 6.1*10^15 Bq.
INES 5 |
The core damage by loss of all cooling function due to the big tsunami. |
Fukushima Dai-ichi Nuclear Power Station Unit 1, 2 and 3, which is in rated power operation, have automatically shut down around 14:46 (JST) in March 11, 2011 because of the Tohoku regional Pacific Ocean Offshore Earthquake.
After that, the power station was attacked by tsunami.
Electricity rooms and seawater pump rooms were flooded, and the cooling function became only the coolant injection of the turbine driven pump.
INES 5 |
Abnormal rise of radioactive dosage value at site boundary (INES Level 4) |
The core damage by loss of all cooling function due to the big tsunami.-Provisional 2
Fukushima Dai-ichi Nuclear Power Station Unit 1, 2 and 3, which is in rated power operation, have automatically shut down around 14:46 (JST) in March 11, 2011 because of the Tohoku regional Pacific Ocean Offshore Earthquake.
After that, the power station was attacked by tsunami.
Electricity rooms and seawater pump rooms were flooded, and the cooling function became only the coolant injection of the turbine driven pump.
