Professor Hayakawa went to Koriyama City in Fukushima Prefecture and walked in Kaiseizan Park right near the City Hall. Compared to his walk in Edogawa-ku, Tokyo on the previous day, the radiation levels in Koriyama City is markedly higher (no surprise).
This time, the professor is armed only with his personal survey meter that only measures gamma ray. He seems to have a protective case on the survey meter, so I don't think he is laying down the survey meter "naked" on the grass or dirt. (He's been doing this for one year now in various locations, after all.)
He took the measurement of "black dust" at 4 locations:
6.331 microsieverts/hr (in the City Hall parking lot)
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