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Reports: Workers told to underplay Fukushima radiation dosage

Handout / Reuters

Workers wearing protective suits remove unused nuclear components stored in the spent fuel pool of the tsunami-crippled Fukushima Daiichi Nuclear Power Plant No. 4 reactor building on Thursday.

A subcontractor urged workers at Japan's stricken Fukushima nuclear power plant to put lead around radiation detection devices in order to stay under a safety threshold for exposure, according to reports. 

An executive in his mid-50s told the workers in December to attach the lead plates to the alarm pocket dosimeters that plant owner Tokyo Electric Power (TEPCO) had given them with to monitor exposure, sources close to the matter said, according to a report by Kyodo News on Saturday. 

Dosimeters can be worn as badges or carried as devices around the size of a smart phone to detect radiation. 

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Nine workers wore the lead plates around the devices once after the executive's request, public broadcaster NHK said, citing the subcontractor's president. 

Japan's disaster at the Fukushima nuclear power plant in March 2011 contaminated the land around it so badly that the area was effectively a write-off. Today the radiation-infected area is known by a name Ray Bradbury would like: "the exclusion zone." NBC News Chief Foreign Correspondent Richard Engel reports from inside the zone, part of his report for Rock Center with Brian Williams airing Wednesday, Mar. 7, at 10pm/9c on NBC.

Japan's health ministry said on Sunday it would investigate the reports, Reuters reported. 

Japanese law has set an annual radiation exposure safety threshold of 50 millisieverts for nuclear plant workers during normal operations. 

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But a massive earthquake and tsunami that crippled the Fukushima plant in March 2011 led to a breach of containment structures that released radiation, keeping large areas around the plant off limits more than a year later.

A Tokyo Electric Power spokesman told Reuters the company was aware from a separate contractor that Build-Up made the lead shields, but that they were never used at the nuclear plant.

Build-Up could not be reached for comment, Reuters reported. 

Reuters contributed to this report.  

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