Saturday, March 19, 2011

Radioactivity surveillance in Japan

This is a map of Japan with all the radioactivity monitors.
Select one and click on "Check data"


View 東北関東大震災・非公式・放射性物質モニタリングポストMAP / Japan quake radioactive material monitoring post MAP in a larger map


This is a graph of the 30 last days monitoring in Tono, north of Okazaki, in Aichi prefecture:

















For info:
The unit is µSv (micro Sievert), which measures the effect of ionization on the living tissues, or the biological effect of radiation.
A nuclear plant rejects 1 µSv in 1 year, which is 1000 times less than the natural radioactivity.
A human should not be exposed to more than 1 mSv.
The annual average natural radioactivity in France is 2.4 mSv, which is made of
Human body activity : 0.34mSv
Solar activity: 0.38mSv
Houses (radon), soil and material: 1.68mSv

The distribution of unnatural exposition to radioactivity in France:
Medical treatment and examination: 1 mSv
Past nuclear tests: 0.10 mSv
All nuclear plants in France : 0.02 mSv




This one is at the Shizuoka nuclear plant:














Here, the unit is nGy/h (nano Gray per hour)
It measures the ambient radioactivity as energy absorption of ions radiation by mass of matter.
The natural ambient radioactivity in France is 91 nGy/h, with values between 30 and 160 nGy/h.
The monitors located at 1 km of each plant measure an average of 72 nGy/h.