5 ms·

Real-time map of Japanese Geiger counter readings

• pyrhho 16y ago
  ^ powered by pachube.com
• davepm 16y ago
  would be more useful if it were to shout measurements in sieverts/hr rather than Gray/hr, but I can understand that would be a hell of a lot more complex ;) Interesting all the same.
  • frevd 16y ago
    "For X-rays and gamma rays, these are the same units as the sievert (Sv)." http://en.wikipedia.org/wiki/Gray_(unit) http://en.wikipedia.org/wiki/Gray_(unit) ADD: "Sievert = Biological effectiveness factor unique to the type of radiation * Gray" http://www.hicare.jp/en/09/hi03.html http://www.hicare.jp/en/09/hi03.html
    • davepm 16y ago
      True, but Gray is for measurement of absorption by ANY material, Sievert is for measurement of absorption by biological material, so you would also need to apply the tissue weighting factor to the gray/hr measurement.
• manveru 16y ago
  I must be missing something, but [1] says "A whole-body exposure to 5 or more gray of high-energy radiation at one time usually leads to death within 14 days." I see values of up to 460 Gy/h on this map, what time unit does [1] talk about that 5 is deadly but 460 is normal? [1]: http://en.wikipedia.org/wiki/Gray_%28unit%29#Effect_on_the_body http://en.wikipedia.org/wiki/Gray_%28unit%29#Effect_on_the_b...
  • manveru 16y ago
    OK, I'm reasonably sure now that Wikipedia speaks about Gy/s. That means that 5 Gy/s are 18000 Gy/h. 450 Gy/h equals 0.125 Gy/s.
• andrewcooke 16y ago
  one problem is that because you use transparent overlays for the circles, and also colour coding (darker circles are higher values) you get a misleading appearance in heavily sampled areas (which appear darkly coloured just because they have many readings). i'd suggest making the circles opaque (i know it's not going to look as nice, but it will be more useful...)
• gersh 16y ago
  It shows the highest readings away from Fukushima. Why?