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Ask Slashdot: Radiation Detection For Tokyo Resident?
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."
Ask Slashdot anything you want! No need for prior research or common sense.
Even the Setagaya hotspot, caused by a forgotten stash of highly radioactive radium, which was orders of magnitude worse than anything else found in Tokyo, was nowhere near the point where it would have posed any danger to the people in the vicinity.
This is just not something which is worth worrying about, much less spending money on. Save your money for the thing your kid actually needs.
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.
Well, what the best device is depends on what it is you want to measure. Alpha particles are not harmful if on the outside - they can't penetrate the skin - but can be exceptionally nasty if ingested. Beta particles can travel further and through more, but still aren't exceptionally dangerous at the kinds of doses you're likely talking about. Even radioactive particles that emit gamma aren't dangerous in low quantities.
The limestone caves in the Peak District are considered dangerous enough that guides can't go down them on consecutive tours and sections are off-limits to potholers. You should probably wait 10-15 mins after going on a tour before getting into a car if there's a group of you. The source of the radioactivity is a mix of uranium-containing ores and radon-bearing igneous rocks. If you were to encounter anything comparable in Tokyo, you'd be in serious trouble,
In reality, the biggest hot-spot reported to date was due to antiques. In all probability, uranium ore (a very popular mineral for adding a yellow tint to glazes and glass in the 1800s and early 1900s) would be what was found, although depending on the instruments used, radon-based paints (very popular for its glow-in-the-dark properties) is another strong possibility. Neither could be considered remotely a health hazard to your average citizen. In fact, given the volcanic nature of Japan, radon-bearing rocks are almost certainly your number 1 health hazard. For that, you'd want a Geiger counter (only if paranoid) and a decent extraction fan (radon is a gas).
If you're worried about fallout, then put a small plastic tray on the roof to collect rain and borrow a Geiger counter. If the rainfall contains nothing of significance now, then it won't do in the future. It takes a LOT to put something as heavy as dust as high up as the cloud layer.
If you are absolutely paranoid, take a roll of 35mm film into a pitch-black room and unroll it. Cut it into squares. Put each square between two pieces of cardboard that are just thick enough that absolutely no light will get through. Use duct tape round the edges to seal the sandwich up. Radioactive dust is the biggest problem and dust is worst in the corners of rooms, since they're hard to clean. Put a film sandwich in all the corners in your house. Leave them there for, say, about a week. Gather them up and take them to anyone with a darkroom to develop. If the squares are completely fogged over, THEN you can worry. And buy a better vaccuum cleaner. If the film shows little or nothing, then you can be absolutely certain that the only thing that you're in danger of is a heart attack from self-induced stress.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
You cannot do this at home. The equipment you can afford (and use) will basically be able to tell you when to run, but that is it. Radioactive substances have highly different toxicity and the direct radiation effect is often not what counts. Example: Plutonium is completely harmless unless ingested. You skin shields completely against its radiation. However when ingested, if comes close to cells and becomes the most deadly substance known to mankind. Also, air happens to shield its radiation! So measuring it requires a very, very thin layer of the substance to be measures, or better vacuum. And very specialized and expensive equipment.
I advise to invest the effort instead in healthy living. If you can, move far away from Tokyo. Other than that you best bet is to hope for the best.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
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?
Sdelat' Ameriku velikoy Snova!
From http://health.phys.iit.edu/extended_archive/9503/msg00074.html:
.
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.
I was in the park the other day wondering why frisbees get bigger and bigger the closer they get - and then it hit me.
Godzilla?
The world's burning. Moped Jesus spotted on I50. Details at 11.
yes you are right this "background" radiation does occur naturally and no your are wrong their is reason to fear as their is no known safe level of radiation.
Utter BULLSHIT..
There is NO LINK between cancer and radiation in humans at below 100mSv/yr acute radiation dosage or 400mSv/yr prolonged radiation dosage or 4000mSv/lifetime (you can't exceed either of the limits). Period.
And now you are trying to spin this into "there is no known safe level of radiation"??? Seriously. Get a life. Radiation is a *stressor* like 1000s of other things that are far more carcinogenic that you choose to expose yourself to. WTF do you think formaldehyde does to you? Or gasoline? Or submicron dust from car breaks on the street?? All of these are far more dangerous than radiation because these target specific areas of your body.
There is NO KNOWN TOTALLY SAFE LEVELS OF BREATHING OXYGEN. Oxygen is the strongest free radical creator in our body. Now go, and deal with it.
You sound like someone that can't understand that they do not live forever. Hell, I hope you do not drive or get out of the house as that is far more dangerous than if you didn't evacuate from Fukushima and and proceeded to lived 2km from the reactor for next 100 years. But I guess sometimes it is futile to explain magnitude of danger if people have preexisting dogma about something.
"There is no totally safe level of radiation" just like it is not totally safe sitting on your ass typing this up. Yeap, nothing is totally safe.... Geez!
I dont know about the 700 million years part but I do know that all reactor fuel is made from U-235 and is very toxic and radioactive.
It is only highly radioactive AFTER it has been inside the reactor for a while. The radioactivity comes from the fission products which are neutron rich nuclei and so decay via beta decay. These are not produced in any significant quantity outside the reactor core because the U-235 neutron capture cross-section is ~1,000 times smaller for fast neutrons and so there is no noticeable chain reaction from a spontaneous fission event. Before the fuel is in the reactor it only poses a toxic hazard.
If you want proof have a look at this picture. It is someone wearing latex gloves and holding a uranium fuel pellet in front of a container of hundreds of fuel pellets. While this is safe for fresh pellets you would not do this after these pellets have been in the reactor core. Indeed when spent fuel rods (containing the pellets) are removed from a reactor they are stored at the bottom of a pool for a period so some of the radioactive fission products to decay because the fuel is so active.
If Mr/Ms Anonymous wishes to contact me, I can check the gutter etc for him/her. I've checked out friends' places in Chiba and elsewhere. Immediately after Fukushima, prices on detectors rocketed past $1200; now they're back down around $300 and in plentifu supply. The cheapest sensible devices available in Japan at the moment are probably one of the Soeks range. This is a detector, not dosimeter. It doesn't log data, and there's no PC connectivity, for example.It only runs 10 hours on a battery, though. For dosimeter, the DosRAE2 is readily available and, again, reasonably priced. It runs 400 hours between recharges and is designed to be worn as a badge. Lots of alarms. The PC software for logging data and managine multiple DosRAE2 badges is laughably bad, though. If you really want one of these things, I'd definitely go for the simple geiger counter (i.e. Soeks), because you get a very visual idea of what's going on around you. Many of the people using these things around Japan aren't capable of interpreting the results. Hotspots within Tokyo: not seen anything comparable to yer average granite lobby, and nothing anywhere near, say, Colorado.