25 Novembre 2013
November 22, 2013
The Nuclear Regulation Authority (NRA) has released a report recommending specific measures to allow evacuees from areas hit by the Fukushima nuclear crisis to return home. In particular, a plan to evaluate and reduce evacuees' exposure to radiation after returning home based on the amounts of radiation measured by dosimeters they carry is noteworthy as one of the pillars of the recommendations.
The government has so far issued evacuation orders and decontaminated areas affected by the nuclear disaster based on air doses of radiation measured from aircraft. The NRA's report should be highly appreciated, considering that levels of radiation measured by dosimeters individuals carry indicate their actual exposure to radiation more accurately than figures estimated based on air dosages.
However, only delivering dosimeters to residents of affected areas will not ensure safety or reassure them. It is important for the government to explain the results of measurements of radiation exposure on dosimeters to residents in detail and in a comprehensible way.
If residents use dosimeters capable of measuring hourly radiation levels, they will be able to check the levels of their radiation exposure at their homes, workplaces and schools and during commuting to and from their offices or schools. Using such data, residents will be able to reduce their exposure to radiation on their own. To that end, however, they need those with expertise who can provide consultations to them.
The report points to the need for such counselors. The concerned ministries and agencies as well as local governments must consider specific measures to achieve this, such as human resource development and deployment of experts to affected areas.
The government should provide a more detailed explanation of differences between air doses of radiation and individuals' exposure to it. The NRA's recommendations clearly state that actual levels of individuals' exposure to radiation tend to be lower than those estimated on the basis of air doses. However, they have failed to sufficiently explain the reason for such a tendency. As such, some critics say the NRA's recommendations that radiation levels measured by dosimeters residents carry be used to evaluate and reduce their radiation exposure constitute a de facto relaxation of the standards. Unless the government tries to make residents understand such complicated matters, it would cause confusion to them and damage the public's trust in the government.
The report should be appreciated also in that the need to respect each individual's choice, regardless of whether evacuees will return home or not, has been incorporated in the recommendations. The authorities should implement measures to extend assistance that residents really need, including those outside evacuation zones and those who have voluntarily evacuated from their neighborhoods.
The report states that cumulative radiation doses, estimated based on air doses, must decline to 20 millisieverts per year or lower as a precondition for allowing residents taking shelter elsewhere to return home. At the same time, however, the report underscores the need to implement measures to cut down an individual's annual exposure to radiation, excluding that existing in nature, to 1 millisievert in the long term. Some experts argue that annual exposure to 20 millisieverts is too high. It is worth considering to authorize local governments affected by the nuclear disaster to set conditions for allowing residents to return home at their own discretion depending on each area's situation.
Residents are concerned about not only radiation but also employment, education and medical care. It is important for local bodies to set up offices that can provide consultations on all these issues.
The NRA has interviewed officials of affected local governments and private organizations before working out the recommendations, but its efforts to listen to opinions from communities in areas hit by the nuclear crisis are still insufficient. The authorities should continue to interview residents of affected areas, and reflect their various opinions in its response to the disaster.