Data from measurement of environmental radiation levels (Aizu Wakamatsu City measurements)


Regarding the Data from Weekly Measurements

Since April 26, 2011, Aizu Wakamatsu City has been measuring environmental radiation in 8 locations around the city once a week in order to make sure that our city is safe.  However, because starting in April 2012 the Ministry of Education, Culture, Sports, Science and Technology's radiation monitoring post in Aizu Wakamatsu became fully operational, and because the measured readings have leveled off and there have been no significant changes, from June 20, 2012 the city has decided that the measurements will be taken every week by both the radiation monitoring posts and real time dosimeters.
From hereon, excluding Inawashiro Lake Sakka Beach and Ashinomaki spa Bus stop where radiation levels are low and stable, measurements will be taken in the 19 locations listed in the chart below.

Results of measurements by monitoring posts and real time dosimeters (once a week)
Date February 12 February 20 February 26 March 5 March 12
Time 12:00 12:00 9:00 11:00 11:00
Kawahigashi-machi Takatsuka 0.06 0.06 0.05 0.07  0.11
Iimoriyama Tourist Information center 0.03 0.03 0.02 0.03 0.04
Higashiyama spa Munical Car park 0.05 0.05 0.04 0.06 0.09
Minato Citizens' center 0.02 0.02 0.02 0.02 0.02
Kawahigashi-machi Hatta 0.03


0.03 0.03 0.03
Kawahigashi-machi Kumanodou 0.07 0.07 0.06 0.11 0.15
Kawahigashi-machi Hirota nishi Park 0.05 0.05 0.04 0.06 0.09
Matsunaga-danchi 0.04 0.04 0.04 0.05 0.07
Kita Koumin-kan 0.08 0.08 0.07 0.09 0.12
Aizu Wakamatsu Station 0.04 0.04 0.04 0.05 0.07
Higashi Koumin-kan 0.07 0.07 0.06 0.08 0.10
Minami Koumin-kan 0.06 0.06 0.05 0.07 0.08
Oto Koumin-kan 0.04 0.04 0.03 0.04 0.05
Kawahigashi-machi Kitabatake 0.06 0.06 0.06 0.08 0.12
Kouzashi-machi Takaku 0.04 0.04 0.04 0.06 0.10
Kouzashi-machi Kitashigou 0.05 0.05 0.04 0.06 0.08
Kitaaizu-machi Shimoarai 0.04 0.04 0.03 0.05 0.06
Ikki-machi Tsuruga 0.04 0.04 0.04 0.05 0.07
Aizu Wakamatsu City park and Public facilities 0.06 0.06 0.05 0.06 0.07
Unit: Micro Sievert per hour (μSv/h)
Measurements taken at a height of: 1m above the ground
  • Comments (update: March 5, 2013)
  • Snow is effective to block radiation. At present, due to the heavy snow, radiation levels are falling compared to the days before the snow season started


Regarding the Data from Monthly Measurements

Until now, Aizu Wakamatsu City had been measuring environmental radiation in 26 locations throughout the city once per month.  However, since the radiation monitoring posts and real time dosimeters have become fully operational and the measured readings have leveled off, from July 2012 the city has changed the number and location of measured areas and will be depending on the figures from measurements by the monitoring posts and real dosimeters as much as is possible.
The locations where the monitoring posts can not take measurements will continue to be measured by the city directly.
Please refer to the reports in locations closest to where you live as radiation levels in the surrounding areas are nearly the same.

Data from measurements performed in February, 2013

Please see the following chart for date from measurements performed in February 15, 2013 by the city.
Measurement locations Results of measurements (μSv/h)
Turugajou Nishidemaru Car park 0.08
Nanoka-machi Public square 0.07
Kitaaizu-machi Hotarunomori Park 0.04
Kouya-machi Sakaizawa 0.08
Kitaaizu-machi Tamurayama 0.04
Kouzashi-machi Takase 0.08
Otsukayama-boen 0.07
Kouzashi-machi Minamishigou 0.11
Kitaaizu-machi Nishigoan 0.08

About detail survey

Detail survey for the radiation levels were conducted in March, April and November 2012. Here are the data. (Japanese)

About radiation in Aizu Wakamatsu City

The environmental radiation monitoring station at the Aizu Branch of the Prefectural Government Office recorded the highest level of radiation on March 16, 2011 – shortly after the accident at the Fukushima nuclear power plant – but the levels have been continuously falling from that point, and there have been no significant increases since that time.
During the most recent monitoring, there have been no increases in the amount of radiation monitored, regardless of rain or changes in wind direction.
It is thought that during the rain on the night of March 15, 2011 into the early morning of the 16 radioactive materials that were apparent in the atmosphere in the forms of gas and dust were brought to the ground by the rain.
It is also thought that the environmental radiation that we have detected has come from the radioactive materials that fell to the ground that night, and that no new materials have been released into the air or have remained in the air since that time.
At present, there are high radiation levels at some of the rain gutters and gutters in the city.  However, 1 meter or more away from those places, radiation levels are nearly the same level as the rest of the environmental radiation in that area.  It is thought that the effects on us in our daily lives are little.

Assessment by the Aizu Wakamatsu City Radiation Management Advisor

The city is receiving counsel regarding how to deal with radiation from a variety of perspectives from Aizu Wakamatsu City Radiation Management Advisor Dr. Michikuni SHIMO (Expert advisor for the Expert Committee on Radiation Protection of the Nuclear Safety Commission, Guest Professor of Fujita Health University)

Assessment by the Aizu Wakamatsu City Radiation Management Advisor Dr. SHIMO follows below.
"In areas around the world with high levels of natural radiation, there are certain locations where radiation levels exceed 1 microseivert per hour (1 μSv/h). However, there are no reports of any negative effects on the health of the people who live in those areas.
Although radiation levels in Aizu Wakamatsu vary widely in value, it is thought that there is no effect on health for people living in any of the areas in Aizu Wakamatsu."
Here are “Radiation Q&A” by Aizu Wakamatsu City Radiation Management Advisor Dr. Michikuni  SHIMO. (Japanese)

Environmental radiation measurement methodology

The city has been monitoring environmental radiation as described in the synopsis below.
・We are using NaI Scintillation counter type survey meters.
・Measurements are being taken in areas away from building and cars.
・While avoiding areas where water has collected, measurements are being taken in roughly the same areas each time.
・Measurements are being taken 1 m above the ground (Except for ground measurements).
・Measurements are taken at 5 locations (center, east, south, west, north), and the average values are then calculated.

Data management and measurement methods are based on the guidance of the Aizu Wakamatsu City Radiation Management Advisor Dr. Michikuni SHIMO.

The measurements have been carried out in much the same way as Fukushima Prefecture has been carrying out their measurements, and from November 15th, the measurement instruments being used by the city are similar to the instruments being used by Fukushima Prefecture.

Contact Information

  • Kankyo Seikatsu-ka (Environment and Community Services Division of Aizu-Wakamatsu City Hall)
  • TEL:[ 0242-39-1221 ] (Japanese Only)
  • FAX:[ 0242-39-1420 ]
  • メール送信フォームへのリンクEmail: Kankyo Seikatsu-ka

  • Kikaku Chosei-ka (Planning and Coordination Division of Aizu-Wakamatsu City Hall)
  • TEL:[ 0242-39-1201 ]
  • FAX:[ 0242-39-1400 ]
  • メール送信フォームへのリンクEmail: Kikaku Chosei-ka