The Nuclear Regulation Authority decided Wednesday to raise the maximum radiation exposure limit for nuclear workers in emergencies to 250 millisieverts from the current 100, starting from next April.
Following the 2011 disaster at Tokyo Electric Power Co.'s Fukushima No. 1 nuclear complex, the maximum limit of cumulative exposure was raised to 250 millisieverts as an emergency measure for workers at the plant, but was lowered back to the previous limit of 100 in December 2011.
In light of the Fukushima meltdowns, the regulator had been considering raising the limit in the event of another disaster as Japan gets closer to reactivating some of its reactors, which remain offline amid heightened safety concerns.
Shunichi Tanaka, the NRA's chairman, told a news conference that the current limit could be an obstacle in containing a crisis in the future, and the revision, which will entail a legal amendment, is "a step forward" in addressing the issue.
The regulator said it believes raising the limit to 250 millisieverts is appropriate based on overseas standards and scientific studies.