Japan Cuts Radiation Exposure Limit for Fukushima Plant Workers

Nov. 1 (Bloomberg) -- Japan’s government lowered the maximum allowable exposure for workers at Tokyo Electric Power Co.’s crippled atomic station after radiation levels fell.

The limit for new workers at the Fukushima Dai-Ichi nuclear plant was lowered to 100 millisieverts from 250 millisieverts, according to an ordinance by the Ministry of Health, Labour and Welfare that went into force today. Staff assigned to some tasks and those who have already worked at the site are exempt from the revised limit.

As many as 3,500 staff are working every day to contain the crisis almost eight months after the March 11 quake and tsunami crippled the station. The utility known as Tepco and the government have said they are on track to bring the damaged reactors into a safe state known as cold shutdown by the end of the year.

The International Commission on Radiological Protection recommends a maximum dose of 500 millisieverts in a nuclear accident except during rescue operations, according to the health ministry. Exposure of 100 millisieverts in one year is the lowest level at which any increase in cancer is evident, according to the World Nuclear Association.

The ministry raised the maximum exposure limit for workers at the plant to 250 millisieverts from 100 millisieverts on March 15 to enable workers to stay longer on the site. Almost 140 workers had been exposed to more than 100 millisieverts by the end of August, according to the health ministry’s website.

To contact the reporters on this story: Tsuyoshi Inajima in Tokyo at tinajima@bloomberg.net

To contact the editor responsible for this story: Amit Prakash in Singapore at aprakash1@bloomberg.net