Tracking radiation levels in Japan | Hacker News Reader

Tracking radiation levels in Japan

rdtn.org

29 pointshuslage15 comments

Just a lurker here, but whoever is running this site is clueless.

It lists figures like "800Gy/h" which is far higher than the radiation level at Chernobyl, right after the accident, standing right beside the blown reactor.

If you check the sources, the units are in nano Gy/h. Their conversion to milliSievert is closer but still off by a factor of a 1000.

So the highest reading I can find is 700nGy/h at Hitatinaka: http://www.houshasen-pref-ibaraki.jp/present/result01.html

If you turn that into a yearly dose, using a weighting factor of 1 as the monitoring station website suggests, that's 6milliSievert/yr: the average yearly dose from background radiation. Exciting!

There's really no justification to make such a website.

“There's really no justification to make such a website.”

That seems like a very strange conclusion. How did you arrive at that? Wouldn’t it be good to know from yet another source that radiation levels currently really are nothing to worry about?

Their text: "This ongoing crisis has highlighted the need for trusted sources. With conflicting reports of radiation levels in affected areas, we wanted to build a way to report and see data in an unbiased format.

This site is not meant as a replacement for government nor official nuclear agencies. Our hope is that data sets from various sources can provide additional context to the official word in these rapidly changing events. ..."

They're using loaded language. They don't say that the official reading are not credible, but let's take a few measurements to make sure.

Background radiation levels vary quite a bit due to surrounding geographical features. A reading from a government station is made under a controlled environment, so a prolonged and large increase in their readings is a good indicator of possible contributions from artificial sources. Getting people to run around with consumer radiation meters isn't going to produce credible data, especially when people are more likely to submit a sample if they "find" an unusual reading.

Also, they're calling for contributions from people in Japan. Yet they do so not in their native language. It seems to me that their intent is that they want radiation readings primarily from English readers i.e. not Japanese.

So you have no problem with the concept, just this specific implementation? There are more understandable ways of saying that.

Radiation dose chart...

http://xkcd.com/radiation/

According to that chart 100 millisieverts/year (or 0.01 per hour) is linked to increased cancer risk. The readings in cities near the reactor look like between 0.1 and 0.8. Not good if it doesn't go down.

Right - Note, that those are rates per hour. Which means for the .8/Hour, you are seeing 19.2 mSv/Day. You hit that 100 mSv total in about a week. That's bad for two reasons, #1, it's exceeding the 100 mSv baseline, but also, I have to believe that getting that much radiation in a week, instead of a year, can't be good for you either.

This is a great idea but it would be much more useful if the pins were color-coded to indicate danger levels.

They are. Gray indicates a complete lack of danger. I'll ask them to add a legend.

Anyone else find it ironic that all the people flying out of Tokyo are exposing themselves to more radiation than those who remain there?

Except those flying out of Tokyo land eventually, thus they have a cap on their exposure.

There's quite a bit of misleading info in some news reporting making numeric comparisons between numbers representing different types of data (activity totals versus exposure rates) and in some cases mismatching units too. At least there seems to be plenty of monitoring going on in Japan, and wide access to frequently updated data. NHK today was reporting the government website now has hour by hour values tabulated. I think that's to help people understand that the daily averages are mostly well below the peak values that get attention. Using a peak hourly rate value for a daily or longer calculation may cause people to over react. (Of course people may have other exposure through food, water etc.)

Studying two other incidents, one at a Japanese fuel facility in 1999 (closed in 2003) and the other with a U.S. army Idaho Falls (Dugway testing grounds) reactor that went critical in an accident in 1961 provides insight into the neutron-moderating behavior of water, and interesting case studies of exposure to people after the initial events. Less known than three mile island, both are significant.

https://secure.wikimedia.org/wikipedia/en/wiki/SL-1 https://secure.wikimedia.org/wikipedia/en/wiki/Tokaimura_nuc...

It strikes me as a site for scamming people, http://bit.ly/fgGX3a sure doesn't sound like a normal way to access the Red Cross. The retailing links are fishy too.

The Amazon link is an affiliate link, all others are clean. Bit.ly provides a simple service to shorten links, and some additional features like click counting.

The Marian Steinbach blog entry "Japan Radiation Open Data" referenced in the article has solid raw data links.

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