JP

FAQ about How to Read the Ambient Dose Rate Map

Q.

Why is the ambient dose rate very high at one point?

A.

Ambient dose rates temporarily increase associated with snowfall or rainfall.

Explanation

This chart shows the daily maximum, average, and minimum of ambient dose rate in Aomori City, Aomori Prefecture. Air radiation mostly comes from natural radiation from the ground and cosmic rays. When there is rainfall or snowfall, natural radionuclides in the atmosphere are “washed down” to the ground, and doses increase after rainfall or snowfall. When snow piles up high, the snow blocks radiation from the ground and doses reduce.

空間線量率が一時的に高くなったグラフの説明図

Q.

Why does the ambient dose rate temporarily increase even without change in the weather?

A.

Ambient radiation occasionally becomes highly affected by artificial radiation used for non-destructive inspection.

天候に変化が無いのに、空間線量率が一時的に高くなったグラフの説明図
PAGE TOP