Air dose rate of Tokyo measured by citizens

Original Text from Zukunashi no Hiyamizu's Blog : http://inventsolitude.sblo.jp/article/85338449.html

There are only 5 monitoring posts in Tokyo set up by administrative office, which you can see real time air dose rate of Tokyo where 12 million people live in.  

Citizens in Tokyo fear radioactivity effect and share air dose rates measured by themselves.

“Hakatte Geiger!”, the web-site for the purpose of sharing measured air dose rate, established in June 2011 and now 4 thousand people register for this site and provide air dose rates measured by themselves.

In this site, there is a web-page named “Hakattayo Response Catalog”.  You can see vast amounts of air dose rates that registrants measured at requested spots.  

I calculated average values and maximal values on 23 wards and other local municipalities in Tokyo for each referring to posted rates on “Hakattayo Response Catalog” .  As a result, I lead to 2 conclusions as follows;

1. Those calculated values indicate high air dose rate in the east and west of Tokyo.

2. I confirmed that there was a certain level of integrity between air dose rates measured by MEXT (Ministry of Education, Culture, Sports, Science and Technology) that you can see the details at the site of “The Distribution Map of Radiation Dos, etc.,”, and those posted on “Hakattayo Response Catalog”.

As for air dose rates posted on “Hakattayo Response Catalog”, since each registrant measured at different time and date and used different Geiger counter, you have to consider such accuracy differences and radioactivity decreases as time passed.  

In this case, I calculated these values as premises for lack of strictness.

As far as interregional comparison, there is sufficient data on each municipality and I don’t think these results undermine the credibility lacking strictness.  Also I make sure that the results have the credibility by comparing with the air dose rate measured by MEXT.

If you would like to make a closer examination of time and date, instrument, measured altitude and air dose rate on certain spot, please refer to “Hakatte Geiger!”.

Under the law of Japan, general citizen is strictly restricted to access to the area where there is more than 40,000Bq radioactivity per square meter as “Radiation Controlled Area”.  The air dose rate is about 0.14μSv/h correspond to this level of contamination.  According to average values on the map, it is a shock to find out that many regions indicate more than 0.15μSv/h.


link url

Hakatte Geiger!
http://hakatte.jp/

Hakattayo Response Catalog
http://hakatte.jp/response/

There are only 5 monitoring posts in Tokyo
http://ma-04x.net/2.html

The Distribution Map of Radiation Dos, etc.,
http://ramap.jmc.or.jp/map/eng/