Comparing radiation in Kona Hawaii to Tokyo Japan

Since the March 11 onset of the nuclear catastrophe in Fukushima, Japan we have been concerned about radioactive fallout in Kona. However, our radiation monitoring, which started in December 2007, has consistently shown low levels of radiation on the island of Hawaii.

Several groups in Japan have been doing independent radiation monitoring of Tokyo and the Fukushima areas outside of the exclusion zone. We commend their great efforts and work to make a large collection of independent radiation data available to the public. Most radiation levels reported so far in Tokyo show minor increases, but many reports closer the reactors show significantly increased levels of radiation of up to 50 times background or more.

There have been video reports on YouTube showing increased radiation levels in the parks and streets of Tokyo.  On the internet one can never be sure what is real, so to offer a comparison for those with access to a detector, we posted a video of the low background readings here in Kona. You can compare our video to a video below showing higher readings in Tokyo.

Our detector measures in milli-REMs and the Tokyo detector in the video below measures in micro-Sieverts. (1 micro-Sievert = 0.1 milli-REM)  Our Kona readings are between .006 and .01 milli-REM which is equivalent to 0.06 and 0.1 micro-Sieverts.  In the Tokyo readings, he is getting up to 2 micro-Sieverts which is 20 times higher than here in Kona. We have a conversion gadget to help with converting between the different units of the instruments being used.

2011 Kona, Hawaii	2011 Tokyo, Japan

The concern we have about the radiation levels shown in the video in Tokyo is that the detector shows a huge drop in the radiation level, almost back to normal, when the detector is held up higher. When the detector is set on the ground it gets very high level readings which could indicate alpha or beta emitting nuclear contamination on the ground. With gamma emitting contamination, holding the detector a few feet higher usually does not decrease the readings. Though alpha radiation can’t penetrate in the air more than a few centimeters, it is 20 times more damaging to the body tissue than gamma or beta radiation. Alpha radiation external exposure can cause rashes where it touches the skin.

Below are links to other radiation monitoring efforts in Japan being performed by independent organizations and individuals

This is a link to an interesting project displaying radiation readings measured by teams that have attached detectors to car windows and reported readings combined with GPS data around Japan.

This is a video of radiation monitoring in an inhabited area near Fukushima in Koriyama park which shows 17 micro-Sieverts, which is over 8 times higher than the readings in Tokyo in the other video.