We have been sequentially evaluating exposure doses of workers at Fukushima 
Daiichi Nuclear Power Station in March and April in two categories as below:
(1) primary and secondary evaluation of internal exposures (More detailed 
    secondary evaluation is done to workers who exceeds 20mSv by the 
    primary evaluation)
(2) external exposure doses
    We have been sequentially submitting interim reports to Ministry of 
    Health, Labor and Welfare on below matters as and when the due date 
    comes and making announcements:
(a) Primary evaluation results of internal exposure doses
    (233 out of 3,771 persons as for March and 1,313 out of 4,567 persons 
    as for April will be evaluated later)
(b) From (a), secondary evaluation results of internal exposure doses for 
    workers with the aggregate of internal exposure doses and external 
    exposure doses exceeding 250mSv  (6 persons)
(c) From (a), secondary evaluation results of internal exposure doses for 
    workers with internal exposure doses exceeding 100mSv (12 persons 
    inclusive of 6 persons per the above (b))
                     (already announced on June 10, 20, 30m July 7 and 13)

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 Today, we announce that we finished the secondary evaluation of internal 
 exposure doses for workers with "over 50mSv and less or equal to 100mSv" 
 per the above (a) and reported to Ministry of Health, Labor and Welfare 
 per the attachment.
 The number of workers with the primary evaluation result of "over 50mSv 
 and less or equal to 100mSv" was 94 (announced on July 13). Out of these, 
 64 persons had the same range of secondary evaluation results.
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From now on, we are planning to submit reports as below:
·  Primary evaluation results of internal exposure doses for remaining 
   workers per item (a) (July 29)
·  Secondary evaluation results for workers with "over 20mSv and less or 
   equal to 50mSv" including newly identified persons per the above bullet 
   point (August 10)

*1 primary evaluation of internal exposure doses
A temporary evaluation based on the assumption that each worker absorbed 
the entire volume of radioactive substances at the first date of work (if 
the worker began work from the outset, on March 12) resulting in the 
maximum figures of doses.

*2 secondary evaluation of internal exposure doses
As opposed to the primary evaluation, the reevaluated figures such as 
adjusting the date of absorption per each person's behavioral survey and 
conducting detailed measurement by JAEA.

<Attachment>  
 The status of evaluation of doses for workers in charge of the emergency 
 works at Fukushima Daiichi Nuclear Power Station(PDF 16.3KB)