Publication and enforcement of “the Ministerial Ordinance for abolishment of exemption in the Ordinance on Prevention of Ionizing Radiation Hazards in response to the situation resulting from the Tohoku – Pacific Ocean Earthquake in 2011”
An exemption to apply the radiation exposure dose limit of 250 mSv to emergency workers at the TEPCO Fukushima Daiichi Nuclear Power Plant was abolished
Today, the Ministry of the Health, Labour and Welfare published the official gazette and put into force the ministerial ordinance in order to abolish an exemption that allowed an upper radiation exposure dose limit of 250 mSv for emergency works at the TEPCO Fukushima Daiichi Nuclear Power Plant. This happened in light of completion of the process (Step 2) to achieve the state of cold shutdown at “the TEPCO Fukushima Daiichi Nuclear Power Plant as shown in the roadmap toward stabilization of the accident”.
Key points of the revision are as follows.
- The upper dose limit for workers engaged in the emergency works that had been increased from 100 mSv to 250 mSv for unavoidable cases to prevent expansion of the disaster at the TEPCO Fukushima Daiichi Nuclear Power Plant on 14 March 2011, was reduced from 250 mSv to 100 mSv except for certain work specified by the Minister of the Health, Labour and Welfare on 1 November 2011.
- The proposed revision abolishes the increased upper dose limit of 250 mSv applied to the exemption specified by the Minister of Health, Labour and Welfare with the completion of the process (Step 2) to achieve a state of cold shutdown at the TEPCO Fukushima Daiichi Nuclear Power Plant. Subsequently, the dose limits specified in the Article 4 of the Ordinance on Prevention of Ionizing Radiation Hazards will be applied to the radiation works (50 mSv/y and 100 mSv/5 years)*
* For the work to maintain reactor cooling function or function to restrict the release of radioactive materials, the upper radiation exposure dose limit for emergency works, i.e. 100 mSv will be applied to workers in accordance with the Article 7 of the Ionizing Radiation Ordinance.
* As a transitional measures, for the workers who have been engaged in the emergency work at the TEPCO Fukushima Daiichi Nuclear Power Plant and whose effective dose that had received during the emergency work had already been larger than the 100 mSv and who cannot be substituted with other workers (Note 2) because of their high level expertise and experiences inevitable for the work to keep the cooling function of the reactor facility (Note 1), the upper dose limit of 250 mSv will be applied during the period ending 30 April 2012.
- Note 1:
- The cases in which one of following types of work will be conducted in the reactor facility and steam turbine and its auxiliary facility or areas around them with potential ambient dose rate may exceed 0.1 mSv/h:
- Work to maintain cooling functions of the reactor facility or spent fuel storage pool,
- Work to maintain radioactive material release restriction functions
- Note 2:
- Approximately 50 employees of TEPCO