From NHK:

The Japanese government has revised upward the permissible level of radiation exposure for workers at the troubled Fukushima Daiichi nuclear power plant.

The health and labor ministry says that it raised the limit by a factor of 2.5, to 250 millisieverts, in cases of emergency.

The measure was adopted to secure enough time for workers at the power plant to engage in operations such as cooling down of the reactors.

Radiation above 250 millisieverts is said to cause health problems such as a temporary reduction in the number of white blood cells.

The health and labor ministry says it reached the decision after consulting with experts on the possible effects on workers.

The ministry explains that the measure was necessary to prevent a nuclear disaster. It says the international radiation limit is set at 500 millisieverts. It adds that medical experts have no clear knowledge about whether radiation of 250 millisieverts or lower will cause health damage.

Wednesday, March 16, 2011 09:56 +0900 (JST)