I occasionally have people ask me whether I'm worried about the radiation left over from last year's tragic earthquake. Fukushima, where I live, was the prefecture most affected by the earthquake. Many people were forced to abandon their homes and their lives in order to survive the effects.
These machines are used to measure the amount of radiation in a given area. There is at least one of them located outside every one of the schools I work at. They give accurate readings using the standard unit of measuring radiation, the sievert (Sv). The highest recorded level during the Fukushima disaster was 433 Sv/h. To compare, the average in my village is roughly 0.2 Sv/h. A dramatic contrast, to be sure.
Background radiation is the radiation present in the natural environment of Earth. An average person living in the United States of America will be hit with roughly 6.20 Sv/year. While levels such as those at the Fukushima Dai-ichi Power Plant can cause radiation sickness in a short period, levels where I live are safe. I monitor how much radiation filters through my village using this real-time website.
I'm not saying that the village where I live is some bastion of health, but I'm certainly not in any risk of developing cancer or a third arm in the foreseeable future. Since I'll be returning to America in less than a month, my exposure to these irregular levels will have been quite short. Although I have noticed that lately my skin has taken on a pale green color...