The government will raise the maximum ambient radiation level target for the cleanup operation around the stricken Fukushima No. 1 nuclear plant from an hourly 0.23 microsieverts to 0.3-0.6 microsieverts.
The Environment Ministry made the decision after analysis showing that people living in contaminated zones would still have an annual dose of less than the 1 millisievert maximum even at the new, higher hourly target. While relaxing the 0.23 microsievert hourly maximum (which does not include normal background radiation) will make the cleanup operation more efficient, residents of the municipalities affected may find the sudden shift upwards of the “safe” dose worrying.
The ministry will present the revised number to municipalities concerned at a meeting sometime soon. At the same time, the government will present a plan to distribute dosimeters to residents to track their individual doses. Individual exposure varies depending on the person’s location and their daily activities, and the ministry plans to use this detailed data to adjust the intensity of the cleanup operations to best suit local conditions and focus on areas of the most need.
In short, the government is looking to shift away from the blanket cleanup operation of the past three years to prioritizing reducing the radiation doses of residents.