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Japan Medicine

Ask Slashdot: Radiation Detection For Tokyo Resident? 371

Posted by timothy
from the if-you're-warm-you're-too-close dept.
An anonymous reader writes "I'm an American who is living in Tokyo. Stories have started popping up about 'radiation hot spots' in Tokyo and surrounding prefectures so I have begun to worry. I live on the first floor of my apartment building and right by our washing machine there is a gutter out there that is clogged with rain water and mud, which has me especially worried because my wife and I are planning to have kids soon. Obviously no one from the government is going to come by to check our gutter so I feel the need to take matters into my own hands. I have absolutely no idea so I'm asking you guys. What kind of radiation detector should I get? A Geiger Counter? If it measures Gamma rays is that enough? Are alpha and beta dangerous too? I know no one has all the answers regarding radiation but any advice you guys could give me would be great."
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Ask Slashdot: Radiation Detection For Tokyo Resident?

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  • Android app (Score:4, Interesting)

    by Anonymous Coward on Friday October 21, 2011 @06:47PM (#37800214)

    There is an app for that: https://market.android.com/details?id=com.rdklein.radioactivity - and no, it's not one of those fake geiger counter apps, but instead a clever hack using the CCD of the internal camera for detecting beta and gamma radiation. All you have to do is cover the camera, so only radiation events will show up on the CCD. The app counts the events and checks against an established calibration table.

  • by Idou (572394) on Friday October 21, 2011 @07:27PM (#37800520) Journal
    If this were any other topic that required technology, the majority of highly modded posts would point to various resources on how to approach the technology. Some posts would even include first hand accounts. However, if it is dealing with nuclear power, which apparently the majority of Slashdoters are completely sold on, the highest modded posts are, "don't bother." Any ideas on the discrepancy? If you LIKE the technology, then shouldn't you be trying to get more people involved? What geek hasn't wasted $300 on some device they didn't really need? Why is it not worth it this time and who are you to judge that for a fellow geek?
  • by riptide_dot (759229) * on Friday October 21, 2011 @07:27PM (#37800522)
    From http://health.phys.iit.edu/extended_archive/9503/msg00074.html [iit.edu]:

    re: The Radiation Dose from a "Reference Banana."

    Some time ago (when I almost had time to do such things) I calculated the dose one receives from the average banana. Here's how it goes:

    On page 620 of the CRD Handbook on Rad Measurement and Protection, the concentration of K-40 in a "Reference Banana" is listed as 3520 picocuries per kilogram of banana. For those of us who are stuck in certain unit ruts, this is equivalent to 3.52E-6 microcuries of K-40 per gram of banana.

    An average "Reference" banana weighs (masses) about 150 grams (I think.) So, the ICRP Reference Banana contains about 5.28E-4 microcuries of probably deadly K-40.

    Federal Guidance Report #11 lists the ingestion dose (committed effective dose equivalent) for K-40 as 5.02E-9 Sv/Bq or (again, for those of us who are "unit-challenged," 1.86E-2 rem per microcurie ingested.)

    Thus, the CEDE from ingestion of a Reference Banana is 5.28E-4 x 1.86E-2 = 9.82E-6 rem or about 0.01 millirem.

    I have found this "Banana Equivalent Dose" very useful in attempting to explain infinitesmal doses (and corresponding infinitesmal risks) to members of the public. (Interestingly, the anti-nukes just HATE this, and severely critisize us for using such a deceptive concept.)

    Would love to go into more detail, but have to get back to our DEADLY Human Radiation Experiments (i.e., eating bananas.)

    The same table in the CRC Handbook lists 3400 pCi/kg for white potatoes and 4450 pCi/kg for sweet potatoes - so you could carry through the same sort of calculation for Reference Potatoes. Interestingly, raw lima beans come in at 4640 pCi/kg, "dry, sweet" coconut comes in at 6400 pCi/kg, and raw spinach (yum!) comes in at 6500 pCi/kg.

    Considering the fact that the DOE has officially stated that "there is no safe dose of radiation" my advice to you all is to stop eating immediately.

    Oh yes! Almost forgot. Regarding K-40, go into your local grocery store, buy some salt-substitute (there are two common brands, and the one in the white and orange labeled container works best) spread some out on a table and check it out with a GM survey instrument. There it is folks, deadly radioactivity in your grocery store!

    Yours for healthful diets . . .
    Captain Internal Dosimetry
    aka Gary Mansfield, LLNL, (mansfield2@llnl.gov)

    Disclaimer:

    Neither Lawrence Livermore National Laboratory, the University of California, nor the Department of Energy recommends eating bananas.

    -------
    The point of course, is to make people realize that the notion that "there is no safe dose of radiation" isn't necessarily correct. Your granite countertops have trace particles of uranium in them. The Capital Building in Washington DC has so much granite in it that it wouldn't be qualified as a nuclear facility because it already emits too much radiation. We consume radiation all of the time from a variety of sources and our bodies rid themselves of it naturally.
  • by rubycodez (864176) on Friday October 21, 2011 @08:44PM (#37801048)
    I've an even better one, I have sitting here two 10" uranium glass plates, of which of course 0.72% is U-235. The former owners, relatives of mine who gave it too me to make my geiger counter do something fun and interesting for my kids, ate meals off the stuff for decades since they were married. They are in their 80s, that U-235 must be a really slow poison! ha!
  • by wolvesofthenight (991664) on Saturday October 22, 2011 @07:02AM (#37803062)
    Personally, I thing ignorant people *should* be learning about and experimenting with radiation detection equipment. The lack of understanding causes a huge amount of trouble, and this is how people learn. And telling people that they are too uneducated to ever understand this stuff is exactly why the public refuses to trust us when we say that they don't need to worry about Fukishema unless they are next door.

    What they need to be told at the same time they start to measure radiation is Don't Panic. The governments radiation monitoring is very very conservative. If the government panics you might consider being a tad concerned. Yea, a few people will still panic - but you won't stop them no matter what you tell them. And the rest will actually start learning about this stuff.


    So, in answer to this ask slashdot:

    1) Unless the the reactor explodes yet again (and 10x larger than last time), don't worry. Your child will be in far more danger from more mundane problems, like cars, falling out a window, pollution, and electricity - and you can do something about those problems. They are more likely to drown in the clogged gutter than get irradiated by it. But when they are a little older they should love playing in it.

    2) There are not consumer radiation detectors like there are smoke alarms. Unless you work at a reactor, you are normally worried about small leaks with long term exposure. Professionally, those are normally measured by dosimeters. If you ever work at a facility like Los Alamos National Lab, you will have to wear one. You probably could get one to monitor your child, but the money would be better spend mitigating other, more serious, risks - or invest it today and it will help pay for their college...

    3) Low cost hand held radiation detectors that give a live readout should be available from educational scientific supply stores. As others have noted, they are not all that accurate, and you really should not panic without a sold understanding of what is going on. But my high school class had fun when the teacher handed them out. Shortly thereafter the students found the uranium ore that he had stashed in a storage cabinet.

    4) Understanding the risks with radiation does take a lot of research. You need to get a good idea of atomic chemistry. Just a few things you need to understand are the different types of radiation (electro-magnetic, alpha, beta, gamma, neutron, etc), what damage each type does, ionizing radiation, how it does biologic damage, and the ability of your body to repair damage. One thing to look into is how radiation danger is often evaluated based on the Linear No Threshold Model, and how that hypothesis is strongly disputed for low levels (in my non-expert view, disproved).

    5) Sources: you can start by checking Wikipedia and google, but as you know they are not always accurate - and they are prone to getting overrun by alarmists. I don't know how much the Wikipeida editors actually know about radiation, vs just think they now.

    One source I like is Enginering Disasters: Lessons to be Learned, by Don Lawson. He has several chapters on radiation, along with a good discussion of the Linear No Threshold Model. Some of his points are not as well supported as I would like, but still worth considering.

    Another source to consider is entry level collage physics text books. Some of them should cover the basics of nuclear chemistry and radiation. For this topic, previous editions are very cheap and just as good (or better) as long as they were published within the past 30-40 years.

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