Potential Iode-131 Cloud Spread - Centrale nucléaire de Fukushima Daiichi
The colour scale shows a total of five colours. „Area A“ (violet) is meant to mark an area with maximum dose rate of 0,3 μSv/h, which corresponds to the amount of the natural background radiation dose. “Area B” (blue) marks a region with 3 Micro-Sievert per hour. Finally, one arrives in ”Area E” with a maximum dose rate of 3 Milli-Sievert per hour. This dose rate is currently certainly not exceeded in the regional area (25x25 km2 box) around the NPP. Irrespective of the assumed emissions, the maximum value of the model is always used to determine “Area E”. In case the situation around the NPP is changing to the worse, the scale would be adapted.
Please keep in mind that, due to the decreasing level of radioactivity in the crisis region, the actual area of influence is likely much smaller than the one displayed here.