We have been evaluating exposure dose of the workers at Fukushima Daiichi Nuclear Power Station in two categories, or "Internal exposure" as well as "External exposure" doses.
The results have been submitted to the Ministry of Health, Labor and Welfare in the order of the due date and announcements were at each time.
Today we submitted a report regarding the exposure dose evaluation as of end of March, 2012 to the Ministry of Health, Labor and Welfare,
- The number of newly engaged workers in March was 483.
The maximum external exposure dose was 19.06 mSv, and no significant value was measured for the internal exposures
- We have reprinted the exposure dose states of "Specific high radiation dose workers*1" and "Provisional measures applied workers*2".
By the end of May, we will report to the Ministry of Health, Labor and Welfare, regarding the status of exposure dose evaluated as of the end of April.
*1 The workers who applied Emergency dose limit (100mSv) shown in "Ordinance on Prevention of Ionizing Radiation Hazards, chapter 7."
Specifically, it means the workers who engaged in the work to maintain the function that cooling reactor facility or spent fuel tank at the area where the radiation dose exceed 0.1 mSv /h and reactor facility, steam turbine and related facilities and surrounding area in the power plant or the work to maintain the function to control or prevent release of huge amount radioactive material due to trouble or break of reactor facility.
*2 The workers who are applied dose limit (250mSv) based on ministerial ordinance relating to special provision of "Ordinance on Prevention of Ionizing Radiation Hazards, chapter 7" until April 30, 2012 even after repealing of the ministerial ordinance on December 16, 2011.
Distribution of Exposure Dose etc. (PDF 42.8KB)