Japan’s Nuclear and Industrial Safety Agency (NISA) has provided further information about the hydrogen explosion that occurred Monday at the unit 3 reactor at the Fukushima Daiichi nuclear plant, the IAEA said, confirming that a hydrogen explosion occurred at unit 3 at 11:01AM local Japan time.
According to the IAEA, radiation dose rate measurements observed at four locations around the plant’s perimeter over a 16-hour period on 13 March were all normal.
All personnel at the site are accounted for. Six people have been injured, the IAEA said, adding that the reactor building exploded but the primary containment vessel was not damaged. The control room of unit 3 remains operational.
Based on information provided by Japanese authorities, the IAEA said it can confirm the following information about the status of Units 1, 2, 3 and 4 at Fukushima Daini nuclear power plant.
“All four units automatically shut down on March 11. All units have off-site power and water levels in all units are stable. Though preparations have been made to do so, there has been no venting to control pressure at any of the plant’s units,” the IAEA said.
According to the IAEA, at unit 1, plant operators were able to restore a residual heat remover system, which is now being used to cool the reactor. Work is in progress to achieve a cold shutdown of the reactor.
Workers at units 2 and 4 are working to restore residual heat removal systems, the IAEA said, although there have been reports that the operator of Fukushima Dai-Ichi nuclear power plant said that the cooling system of the Unit 2 is fully down, which could lead to overheating of the unit and an explosion, similar to those that occurred on Friday and Monday.
Unit 3 is in a safe, cold shutdown, the IAEA said.