TOKYO — Japan’s nuclear safety agency said an explosion Tuesday at an earthquake-damaged nuclear power plant may have damaged a reactor’s containment vessel and that a radiation leak is feared.
The nuclear core of Unit 2 of the Fukushima Dai-ichi nuclear plant in northeast Japan was undamaged, said a spokesman for the Nuclear and Industrial Safety Agency, Shigekazu Omukai.
The agency suspects the explosion early Tuesday may have damaged the reactor’s suppression chamber, a water-filled tube at the bottom of the container that surrounds the nuclear core, said another agency spokesman, Shinji Kinjo. He said that chamber is part of the container wall, so damage to it could allow radiation to escape.
“A leak of nuclear material is feared,” said another agency spokesman, Shinji Kinjo. He said the agency had no details of possible damage to the chamber.
Radiation levels measured at the front gate of the Dai-ichi plant spiked following Tuesday’s explosion, Kinjo said.
Detectors showed 11,900 microsieverts of radiation three hours after the blast, up from just 73 microsieverts beforehand, Kinjo said. He said there was no immediate health risk because the higher measurement was less radiation that a person receives from an X-ray. He said experts would worry about health risks if levels exceed 100,000 microsieverts.