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A Handy Radiation Dose Chart From XKCD
An anonymous reader points out Randall Munroe's latest contribution to public health awareness, a "chart of how much ionizing radiation a person can absorb from various sources, compared visually. 1 Sievert will make you sick, many more will kill you, however, even small doses cumulatively increase cancer risk." It's a good way to think about the difference between Chernobyl and Fukushima.
DELICIOUS.
Interesting info. Perhaps some of the anti-nuclear hysterics like this clown should read it... instead of watching the news.
Fascinating, the mention of bananas was smart, since there's something known as Banana Equivalent Dose
An additional useful chart can be found here, in a slightly more readable and intelligible format:
http://eq.wide.ad.jp/files_en/110315houshasen_mext_en.pdf
Not as all-inclusive as Randall's work, but still good.
Every experiment which ends in a big bang is a good experiment.
xkcd, not XKCD.
i heart that little reference.
So what you are saying is that XKCD did more research and analysis for a web-comic than the 24 hour news networks do for a story?
I'm sorry, but the link above on the equivalent yearly radiation in Tokyo would only be correct if you were outdoors 24 hours per day, 365 days per year.
Any link to the updated levels of radiation on Fukushima?
Gee, why the fuck doesn't that surprise me?
Do you really believe that the news channels do anything other than bloviate?
There are so many radiation units out there and people keep using them without regard to what they really mean. It's nice that you've got your Sieverts covered. Now you'll have to learn about Grays, Curies, Becquerels, Rads, Rems, and Roentgens. Here's a handy conversion chart.
It's a good way to think about the difference between Chernobyl and Fukushima.
No. It is not a good way to do that. It would have been if it had included measures like "Ten minutes next to the reactor core of Fukushima after partial meltdown" or "Dose from spending an hour on the grounds at the Fukushima plant in 2036". I'm not saying Fukushima is anywhere near as bad as Chernobyl, but if you want to compare them this chart is not what you need.
I found one source that said firefighters had radiation levels of 27 mSV after a 13 hour operation (presumably to cool down the reactor). Which doesn't seem to me to be a severe healthrisk after looking at the chart provided. Maybe I'm wrong but I'm vastly annoyed with the media, given how they talk you'd think people were losing their hair and growing skin lesions.
The Sievert is a measure of ACCUMULATED dose. Time is a factor. Therefore being exposed to 1 Sievert for a second (the real unit behind the sievert is the J/s, which is equivalent to Watts) is the same as being exposed to 1 milisievert for 1000 seconds, or 1 microsievert for 10^6 seconds.
This is also why many measurements are done on a "per hour" basis. 400 milisieverts per hour (near the pool between reactors 3-4) is not harmful to you if you are going to be there for 5 minutes. If you stay there for 2.5 hours, however, you could experience signs of acute radiation sickness.
I find it laughable, however, how the press a) fails to understand this and b) has obvious trouble converting between micro and mili.
Finally one must bear in mind that radionuclides will decay over time (Iodine-131 being the main culprit here, has a half life of 8 days). So in 5 half lives (40 days), most of it will be gone. And also that the chronic health risk of radiation is usually overestimated, especially for such small doses as currently seen in Japan. It's statistical roulette, just like smoking. It just takes one cigarette to unleash the chain of events that will eventually lead to cancer. However the odds of it being the cigarette you are currently smoking are quite small. But if you smoke all your life, you're likely to buy the winning ticket eventually. The same with radiation. There are still living survivors of Hiroshima and Nagasaki, and these people were exposed to far more (and more harmful) radiation - gamma rays vs. beta particles. And yet not that many of them have "grown a third arm". Yes, there have been cancer deaths, but considering the population exposed, it wasn't all that much.
Seven puppies were harmed during the making of this post.
This is not an incredibly informative measurement, it would be more useful to learn of the radiation levels in the evacuated areas (10km & 20km, last I heard) as well as the cautioned areas (30km, stay indoors).
SYS 64738 NO CARRIER
Anyone acquainted with any of the literature in radiation exposure up through the late-1990s (including classic and still standard works like The Effects of Nuclear Weapons by Glasstone and Dolan) will have encountered discussion of radiation exposure in terms of rems, not sieverts. It is useful to know that a centisievert (cSv) is essentially identical with a rem, so expressing doses in cSv terms allows direct comparisons with the large body of older but still relevant literature.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
Would be useful if he gave some comparison with Sulawesi...
I would like to have seen the dosage given by using the backscatter machine at an airport listed.
Deltron 3030 - Virus (music video)
Comparison between the exposure of an aid worker who flew from the US / EU to Japan and right back again, and what he would have accumulated in a week saving people 100 miles away from Fukushima.
Fandroids hate facts.
The latest news is that the (so far very low) water supply radioactive contamination is increasing. It makes sense given all the water they're spraying around there, that it's going to leak into the drinking water supply. So far it's at a low enough level to not be a threat, but the situation is unstable and the doses are increasing on a daily basis.
1 Sievert? What is that in feet?
Coal fired powers stations emit more radioactivity than nuclear power stations and also release greenhouse gases and ash. We should be shutting all of these as soon as possible to protect the Earth and its people. The deaths due to coal mining annually exceed all deaths in over fifty years of nuclear power generation.
It claims 10 microSievert to be the average dose per day and the EPA limit per year to be 1000 microSievert. This means the average dose for the public per year would be 3600 microSievert i.e. 3.6 times the limit. Somehting does not add up.
A number line would have done so much more.
The thing that very few people are mentioning is:
The exposure occurring over the days and weeks.
Not everyone has an x-ray every day.
The Japanese ministry is suppressing both the radiation figures for Fukushima and the areal photos recently taken.
The atom is an amazing thing because it makes people lie so much?
https://www.youtube.com/c/BrendaEM
That was helpful. But after a 10 days of study I'm missing the information about the non-ionizing radiation that the water in those spent fuel pools was there to adsorb. The cancer link is also curious - the WHO report on Chernobyl states 4000 cases of thyroid cancer from milk in children with a 99% survival rate, just 9 deaths. I have cancer myself and visiting a reactor would probably be good for me because tumors hate radiation.
This chart applies only to "prompt" doses. Most of the casualties from Chernobyl (4000 to 8000 fatalities and counting) were from Thyroid cancer caused by exposure of children to radioactive Iodine. This is not just a dose effect, as the same dosage from another material, or of adults rather than children, won't cause these cancers. So, this chart is not appropriate for these long-term dangers.
Radioactive iodine has been found in milk and spinach near Fukushima, ad it is very worrying that the Japanese government is only talking about "immediate effects" when the real danger is long term.
... to dead kittens?
Seeing the wild claim I have seen on various network, and web news aggregator, I would say anybody researching *a bit* did more research than news networks...
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
A coal plant would probably kill more people than a nuclear plant over the same period of time even with "catastrophic" accidents like this. The problem is that people don't go berserk because of 3~10 years reduced life expectancy.
he still hasn't learned how to draw.
Will I gain super powers if I visit the reactor?
I think one major cause of nucleophobia is that doses of a millionth of anything dangerous or less are easily measurable
Negligible doses of most every poison is always around, but are unmeasurable. Radiation radiates its presence and is observed, reported and terrifying.
Do all those boxes remind anyone else of a good old fashioned defrag?
and wonder if he read the recent research on how neurons can use weak rf like signals to communicate with nearby but not directly connected neurons.
Oh, wait.
You're contradicting yourself. If the Sievert already has units of a rate (J/s), then the 400 mSv per hour you mention is a double rate (energy/time^2), some kind of energetic acceleration, which doesn't make sense here. Your second paragraph is correct, but it contradicts your first.
As others have noted, the units for a Sievert are J/kg, not J/s. This is a very important distinction. An accumulated does requires these units, as J/s is a rate, and then you have to know how long a person is exposed, i.e. there is no accumulation. An accumulated dose implies that if you receive 1 mSv, that is all one needs to know: there is no time scale involved. It is a certain amount of total radiation received. Correcting your first paragraph, 1 Sv received in 1 second is (approximately) the same as 1 Sv received in 1000 seconds and as 1 Sv received in one million seconds. Sieverts are therefore a useful measure for directly determining the effects the radiation will have on a person.
So in fact Randall's image is accurate, unless there is some minor error in it that hasn't yet been discovered. Given your own misunderstanding of the situation, I hope the press's confusion is a little less inexplicable. You still come to the correct conclusion, which they often do not, but sometimes, science is hard.
Excellent idea, poorly executed. The graphic is too crowded, contains too much information, and is overwhelming.
Randall needs to read and head Tufte.
I am now scared of bananas.
I had 40 Gray to the head in 1980 and another 40 Gray to a soft tissue tumor in 1982, both go arounds were in 2 Gray doses.
Ingestible isotopes have a far lower threshold of causing problems, you've made a chart of "shine", external source dose. Make a chart of ingested, integrated contamination with increase in death rate by cancer or incidence of cancer for this situation. Risk of death by cancer goes up 0.04% per REM of long term chronic dose (or 0.04% per 10 milli-Sievert), for example. Some colored squares to indicate piles of 1 and 10 dead people, about and beyond the norm, is the way to view this situation.
The level for a mammogram is shockingly high compared to other ordinary x-ray diagnostics. Could this be wrong? Hundreds of millions of women regularly have mammograms. How can their exposure be thousands of times higher than other x-ray therapies? This must be an error.
Tepco has translated the Monitoring data at Fukushima Daiichi and Fukushima Daini Nuclear Power Stations, with all the measures available from 17/march/2011 to 20/march/2011:
http://www.tepco.co.jp/en/nu/monitoring/index-e.html
The next link points to the page in japanese that shows the monitoring data since the emergency was declared:
http://www.tepco.co.jp/nu/monitoring/index-j.html
Mexico: 100% conservative's America now!
So many people talk in terms of the exposure level at Fukushima since the accident, but that's never been the issue. They have, so far, avoided the disaster with some pretty amazing mitigating actions, and some very good luck. Speculation as to what will happen if those attempts at mitigation eventually fail is the scary part, not the *current* risk. But what would happen if their efforts fail and they end up with an exclusion zone that happens to include half the farmland that feeds Tokyo? THAT hasn't happened and probably won't happen, but if it did, all this talk about how wonderful and low the exposure is today would be irrelevant.
As I see it, the real problem is, whether there is a risk of the disaster taking a turn for the worse, it is impossible to gauge the risk because the people in control of information are not as forthcoming as they should be, considering they have been caught lying about things in the past. This, the fact that the people controlling information are already known not to be trustworthy, is the central issue of Fukushima.
-fb Everything not expressly forbidden is now mandatory.
peaked at 10 mSv/h onsite ; mar. 16th
another visual
Has anyone else been having a lot of trouble viewing anything from xkcd lately? In the past few weeks, comics have taken 5-10 minutes (seriously) to load, if they load at all. Some comics haven't loaded at all - I've even tried m.xkcd.com instead - given 5-10 minutes to load.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
The greatest fear should be internal contamination. Many of the radioactive isotopes mimic their non-radioactive elements or have a similar biological uptake. (Strontium vs. Calcium), (normal Iodine 127 vs. radioactive Iodine 131).
For dosage calculations it is important to know if it is an alpha particle, beta particle, gamma ray or neutron. Each has different penetrating capabilities and different destructive potential.
If I had a choice between 1 Sievert of gamma radiation given externally or 10 milliSieverts of an internal dose of Iodine 131 (8 day half life) or Polonium 210 (138 day half-life) I would take the external dose.
Polonium is a wicked producer of alpha particles. When ingested or inhaled it is toxic in addition to giving you a constant source of radiation (rate decreasing by 1/2 every 138 days).
I had a thyroid disorder and I opted for the Iodine 131 treatment instead of surgery. It was an internal contaminant and my sweat and urine were radioactive and I emitted enough radiation that I was supposed to stay away from people for several days (there are biological half-lives for elements in the body that are quite different from isotope decay half-lives). The treatment essentially "killed" my thyroid on purpose since it was on it's own version of a nuclear meltdown.
Need to consider external vs. internal, particle types, radiological half-life and biological half-life on any sort of dosage calculation.
Tisha Hayes
China also did above ground testing. In fact, China did an atomic bomb testing during the Three Mile Island crisis, and the radiation was higher that let go by TMI.
http://barryonenergy.wordpress.com/2011/03/15/three-mile-island-tmi-chernobyl-and-now-fukushima-dai-ichi-%E2%80%93-is-this-the-last-nail-in-nuclear%E2%80%99s-coffin/
Cool. The chart's origin is from the Reed Research Reactor staff.
Fun fact: the research reactor at Reed College is the only nuclear reactor in a private college in the US.
I'm a Reedie alumnus and proud of it!
Since living within 50 miles is about 2 blue boxes, how about living within 50 miles of 50 nuclear reactors? (check INEL in wikipedia). Do they still rate two boxes, or is it multiplied out?
Oh, for extra credit, one of them (SL-1) blew up, and killed 3 people. Does that earn me more blue boxes?
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Since we seem to have experts in this thread, can I ask what the dosage from a bombed-out Iranian or North Korean reactor would be?
We (or the US Gov't) were seriously discussing doing that recently, after all.
...when comparing Chernobyl to Fukushima.
1) Comparing radiation somewhere inside a 50 mile radius around Fukushima I to the radiation next to the exploded reactor at Chernobyl is useless. Radiation next to a dry spent fuel basin will be quite high as well but it is not dangerous for the general population until it explodes some more.
2) We are also comparing a sparsely populated region to one of the most densely populated ones on the planet, smaller amounts of radiation will do more damage here. And by damage I'm not only referring to the damage the radiation may do to humans directly but also to damage like e.g. the inability to use certain food sources - that will become unavailable even when they would likely not be very dangerous on their own.
3) On a technical level, at Chernobyl, one reactor exploded. At Fukushima, we saw several explosions, some of which apparently harmed the other nearby reactors. This is a first. Previous accidents always only involved one reactor.
Chernobyl was ranked 7, Fukushima is ranked 5.
Chernobyl was kept secret during several days, opaque after.
Fukushima data is available (but obfuscated by news media)
Many workers in Chernobyl were knowingly sent to sure death.
Radiation taken by Fukushima workers is monitored and they are not allowed to take more than 250mSv.
Chernobyl radioactive fallout are very dangerous locally, and affected most part of Europe.
Fukushima radioactive fallout, even locally, don't cause much health concern. (Of course food production in the area will have to be monitored.)
Fukushima is still a severe accident, but nowhere near the case of Chernobyl.
The BBC has a helpful guide - not sure it the numbers are the same as XKCD http://www.bbc.co.uk/news/health-12722435
/usr/bin/loonie
It is not true that any radiation will lead to an incremental increase in cancer risk. If that was true population centers where there is more radiation (like Denver where there is less air to shield the radiation from the sun) would have larger cancer rates, but they do not.
In reality, there are amounts of radiation that your body can readily absorb and adjust to in the same manner that your body adjusts to small amounts of toxins in the environment.
Government regulators and the nuclear industry use the theory that any radiation is bad because it is a conservative, safe assumption. The nuclear industry tries to avoid any radiation exposure under the concept of "As Low As Reasonably Achievable" (ALARA).
Radiation from Japan floating over the US will NOT cause "more, but statistically indistinguishable" cancers, as you've heard on TV.
Brian Mann
Nuclear Engineer with 30 years experience.
Too bad slashdot is overrun by pro-nuclear clowns like you.
Growing up radiation was in "rads", then to obscure things when people understood that term, they switched to "Roentgen's", now they are obfuscating things farther with "Seivarts". It's all done in an attempt to scare the sheeple that make up the majority of the population of this planet. Frankly, it just annoys me! It's like constantly changing speed limits signs, so now they would be at something like "furlongs per forte-night" so everyone would be busy trying to figure out what the real "speed" is, rather than actually using the information. That is what this constant changing does - obfuscates the truth.
Gee, why didn't I have this while playing Fallout?
Yes, I am not in opposition to that, but I do raise a legitimate issue: how do you maintain nuclear waste successfully and efficiently? How do you store "spent" nuclear fuel which is still extremely dangerous to humans (hence the need to provide coolant to pools of spent rods for decades)? And I don't mean drop them off the coast of Somalia...
That's the something that coal powered power plants do not have to deal with.
That chart is dishonest and causes me to lose a lot of respect for XKCD's author. He only gives the measurements at towns located far from the plant. Why does he ignore the plant's readings which even today are 2,126 micro-Sieverts PER HOUR. That's the equivalent of getting a chest X-ray every 34 seconds and would expose a person to the maximum annual dose for nuclear workers in 23 hours.
I realized xkcd is the master of sarcasm and irony, and fear over nuclear radiation is great target, but he's way overstating his case. It's nice to throw in the bananna, I did it too in my analysis. There are definite medical estimates of cancer causing from smaller amounts of radiation than 100mSieverts. This is radically oversimplified and optimistic. I have some different figures, from different wikipedia articles (CT scan) and papers in medical journals (no cites handy at this location, sorry) For an adult, estimated increased risk of cancer from an abdominal CT scan: +0.018% Estimated lifetime risk of cancer to a 1 year old from a single abdominal CT-scan: +0.1% head scan: +0.07% Given that there are hotspots 19 miles away reported in the times (can't find the interactive NY Times map. at 171uSievert/hour, it's not that many days before you have a CT-scan worth. So any babies at that location, outside the evacuation radius, have a growing, and measurable risk. Down's syndrome spiked to double the incidence in Europe from babies conceived around the time the cloud from Chernobyl passed over, so obviously genetic damage is measurable, and that implies many deaths, even if we're not so good at measuring it. Estimates vary from thousands (International Health Organization, which seems biased by a relationship with IAE) to hundreds of thousands (various Russian and Ukranian doctor's groups). Anecdotal evidence from visitors to Ukraine reports a LOT of people with cancers in their 40s and 50s, and with severe genetic damage, which is certainly going to shorten their lives. How do you quantify someone who dies at 50 instead of 70 because of radiation? I would say, you define the number of person-years of life lost as a result of an accident, and on that basis, Fukushima is not a joke. I'm going to go out on a limb, and guess this will end up as a minimum of 1 million person-years, and it could easily be far higher when the cancers are all in 50-60 years from now. Just because it's a slow-motion disaster doesn't mean it's less serious than the tsunami, it's just a lot less obvious. The New York Times had an article on dosages: http://www.nytimes.com/2011/03/14/world/asia/14health.html?scp=5&sq=japan%20dosage%20map&st=cse The worst complacency of this graph is that it implies that these are the dosages from Fukushima when in fact the accident is anything but contained. And the more radioactive the site gets, the harder it gets to do any work on it at all. This isn't three mile island. It may not be Chernobyl either , but there's a lot more material there to be dispersed. We can only hope that work to contain the situation is successful.
A zooming presentation of the same material, showing the doses to scale:
http://prezi.com/ocl7xignbv5l/radiation-from-various-sources/
Opinions stated are mine and do not reflect those of the Illuminati
Once again, Freefall pwns all. Radiation story starts here: http://freefall.purrsia.com/ff100/fv00066.htm
Captcha - 'resigned'. As in, I'm resigned to the fact that Slashdot's comment submission form sucks?