JAPANESE OFFICIALS have confirmed that two workers at the tsunami-damaged Fukushima Dai-ichi nuclear power plant in the north-east of the country have exceeded the radiation exposure limit.

Plant and government officials have warned that people who worked without sufficient protection in the early days of the crisis could also show high levels of exposure and about 40 other workers are being tested.

Despite exceeding the government-set limit, the two men are not showing immediate health problems. They will continue to undergo health checks in the long term. The men were responsible for the controls rooms of Units 3 and 4 at the plant and their exposure may be as high as the equivalent of 1,000 abdominal x-rays.

The International Atomic Energy Agency released its preliminary report of an investigation into Japan’s nuclear crisis, which was triggered when the plant was struck by a 9.0-magnitude earthquake and major tsunami on 11 March 2011. The IAEA said that Japan had underestimated the risk of a tsunami. Although tsunami barriers were in place, they were about three times lower than the waves which actually struck in March.

However, the IAEA commended the country’s response to the crisis as “exemplary”.

The plant operator TEPCO plans to bring it to a complete ‘cold’ shutdown by January 2012.

- Additional reporting by the AP

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