Monday, April 18, 2011

Hot Schools in Fukushima has added a national radiation map to their existing database which includes air, soil, rain, food. They have also added a map of radiation at Fukushima Prefecture schools, as measured by the Fukushima Prefecture Disaster Office over three days, at present.

Bad news in this map is that schools in Fukushima City and elsewhere with numbers up around 4 to 6 microsieverts per hour are far above the 20 MILLIsieverts per year the govt is setting as an evacuation threshold. Do the math: Anything over 2.3 MICROsieverts an hour will accumulate to more than 20 MILLIsieverts a year. They should err on the side of caution considering: the intl standard for added dose is 1 millisievert annually, not 20; these are children, not adults; there is a possibility of ingesting and inhaling radioactive particles; and emissions and deposition levels are continuing and accumulating. They should evacuate.

One argument against evacuation is that these levels may be temporary, and go down soon, but that is doubtful. Even if so, I think they should temporarily evacuate the cities of Fukushima (290,000ppl), Nihonmatsu (61,000ppl), and Sukagawa (80,000ppl), or, if that is impossible, evacuate at least the children. Note that our levels down here in Chiba are 0.055 microsieverts per hour today, only 1% of what is measured at some of those schools. (compare to 5.5)

If the govt keep to their stated standard of evacuating places with a risk of accumulating over 20millisieverts/year, then they will announce an evacuation. If they keep to their established precedent of moving slowly (and erring on the side of radiation), the announcement will come in about 2 weeks (and allow another month to take effect).

Using the slider on the school map also reveals wider investigations done on previous days. I guess they are not cumulatively added to the map because yesterday's measurements may have changed by today. There are 2 measurements: at 1cm (above the soil, I assume), and 1 meter.

Measurements of the known VERY radioactive areas were done mostly on the first day.

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