The decommissioning crew at the defunct Fukushima No. 1 power plant is losing 174 members who have reached the legal limit for radiation exposure.

As of January, the 174 had topped the limit of 100 millisieverts in five years spelled out under the Industrial Safety and Health Act, which also limits nuclear power plant workers to a maximum exposure rate of 50 millisieverts per year.

The plant has about 14,000 registered workers, but 2,081 have already received 50 to 100 millisieverts of exposure.