The operator of Japan's tsunami-damaged nuclear plant said Tuesday it is installing rooftop vents and taking additional safety measures at two other plants to help cope with any severe accident in the future.
Tokyo Electric Power Co. said it will add vents to seven reactors at the Kashiwazaki-Kariwa plant in north-central Japan to prevent devastating hydrogen explosions like those that occurred at the Fukushima Dai-ichi plant in mid-March.
Until the vents are installed, TEPCO said it will store equipment that can cut emergency holes in the reactor roofs to release pressure in case of a hydrogen buildup, and take other safety steps at the two plants.
Several hydrogen explosions occurred at the Fukushima Dai-ichi plant that spewed radiation into the environment after the March 11 earthquake and tsunami.
TEPCO's measures followed an order last week by the Nuclear and Industrial Safety Agency instructing all Japanese nuclear plant operators to improve their preparations for severe accidents. The order came after the government submitted a report on the Fukushima accident to the International Atomic Energy Agency.
The report pointed out the need to reduce the risk of hydrogen explosions inside containment buildings as one of the lessons learned from the Fukushima crisis, the world's worst nuclear accident since Chernobyl.
NISA spokesman Hidehiko Nishiyama said the agency will inspect all nuclear plants Wednesday and Thursday to examine their preparedness.
"The idea is to take steps to address the issues raised in the government report, based on lessons we've learned so far from the Fukushima accident," Nishiyama said, adding that more measures may be required in the future. "The point is to keep the containment building intact."
In the report to the IAEA, Japan admitted it was unprepared for a severe nuclear accident like the Fukushima disaster.
Other nuclear operators also submitted similar reports to NISA to meet a Tuesday deadline. In addition to hydrogen release measures, the utilities said they will improve protection for workers dealing with emergencies accompanied by radiation leaks, install backup communication systems and keep bulldozers on site to remove debris.
Japanese nuclear plant operators have already taken other steps to improve accident management since the disaster, including installing additional backup diesel generators at elevated locations to protect them from a tsunami, increasing the water tightness of reactor building doors and other measures to maintain core cooling capacity during blackouts.
On Tuesday, Japan's Cabinet approved a bill to help TEPCO meet the massive costs of compensating people affected by the crisis.
The bill, which needs to be approved by parliament before it can take effect, would establish a fund comprised of public money and contributions from utilities that would financially support TEPCO as it faces a deluge of damage claims. The government is to fund the scheme with special bonds.