There’s a lot of discussion of radiation from the Fukushima plants, along with comparisons to Three Mile Island and Chernobyl. Radiation levels are often described as “<X> times the normal level” or “<Y>% over the legal limit,” which can be pretty confusing.
Ellen, a friend of mine who’s a student at Reed and Senior Reactor Operator at the Reed Research Reactor, has been spending the last few days answering questions about radiation dosage virtually nonstop (I’ve actually seen her interrupt them with “brb, reactor”). She suggested a chart might help put different amounts of radiation into perspective, and so with her help, I put one together. She also made one of her own; it has fewer colors, but contains more information about what radiation exposure consists of and how it affects the body.
I’m not an expert in radiation and I’m sure I’ve got a lot of mistakes in here, but there’s so much wild misinformation out there that I figured a broad comparison of different types of dosages might be good anyway. I don’t include too much about the Fukushima reactor because the situation seems to be changing by the hour, but I hope the chart provides some helpful context.
(Click to view full)
Note that there are different types of ionizing radiation; the “sievert” unit quantifies the degree to which each type (gamma rays, alpha particles, etc) affects the body. You can learn more from my sources list. If you’re looking for expert updates on the nuclear situation, try the MIT NSE Hub. Ellen’s page on radiation is here.
Lastly, remember that while there’s a lot of focus on possible worst-case scenarios involving the nuclear plants, the tsunami was an actual disaster that’s already killed thousands. Hundreds of thousands more, including my best friend from college, are in shelters with limited access to basic supplies and almost no ability to contact the outside world. If you’re not sure how to help, Google’s Japan Crisis Resource page is a good place to start.
Edit: For people who asked about Japanese translations or other types of reprinting: you may republish this image anywhere without any sort of restriction; I place it in the public domain. I just suggest that you make sure to include a clear translation of the disclaimer that the author is not an expert, and that anyone potentially affected by Fukushima should always defer to the directives of regional health authorities.
xkcd 
Did you put the new TSA machines in here? Would be interesting to see where they fall on your chart.
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Please disclose your source for “One-day dose (~3.6 mSv) at two sites 50 km NW of Fukushima on 3/16 seen again on 3/17.”
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Can you do this in rem? I have to convert everything in my head to make the units right for me. It’s like the chart is in centimeters but I think in inches.
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…
is ellen married?
ie: yum
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Great chart! It’s by far the best one I’ve seen yet trying to calm the fear of another Chernobyl. I’ve republished it on my site, thanks.
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Is there a unit for units of radiation per unit of time? That might make some aspects a little clearer. If there isn’t, we should propose the Munroe, where 1Mr=1Sv/1s. Even without Mr’s, the graph is very well done.
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Is there a unit for radiation per time? We should propose the “Munroe”, where 1Mr=1Sv/1s. Even without, great graphics. I forwarded to all my friends and teachers.
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@moderator
Radiation exposures are a complicated topic. I’ve offered technical criticism of the chart. I have not been rude or foul in my comments. At worst I have been blunt.
All I can think now that I am blocked from responding to those who have addressed my criticisms is that you are too immature to take criticism or are a shill for the nuclear industry.
Is censorship really something you want to engage in? It’s a shameful act.
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A suggestion (may have already been made: I haven’t checked all the comments): add radiotherapy on the chart. How much for a typical breast cancer treatment? How much do healthy tissues close to the treated tumour typically get? How much for bone marrow irradiation in a leukemia treatment?
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PULITZER!!!!!!!!!!
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Thanks for this it was very interesting, however I was wondering if you knew what the error ratio for this chart was?
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This chart was linked to from “Dagens Nyheter”, the biggest morning newspaper in Sweden.
http://www.dn.se/nyheter/varlden/stralning-i-reaktor-miljontals-ganger-over-normalvarde
Congratulations, Randall, you are now world famous in Sweden 🙂
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Well,
as of today , reactor #2 has been measured to reach a radiation output of 1Sv / hour at one location
You can all read the charts to try and grasp what that means
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I’ve normalized Randall’s data to a year, to account for the varying exposure times of his data. A “normalized” graph is available here:
https://www.sourcepole.ch/2011/3/27/randall-monroe-s-radiation-dose-data
What’s maybe more interesting for people that want to juggle with and better understand the data is that I’ve put it into spreadsheet form. Available under the same URL above.
When “normalized” to a year the measurement from Fukushima from Randall’s graph look quite a bit scarier.
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In their March 23 issue, the Calgary Sun reused your chart here almost one-to-one; they did provide credit (nice of them) but it’s in about 1-point font.
(The credits are the tiny white smudge of text in the bottom left of the black frame; I’m sorry for the blurrycam picture.)
Mostly I’m irked they dumbed down your explaining text to the point of removing most of its worth and no longer quote any of YOUR sources.
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Thank you very much for this very clear explanation.
If you are interested in the effects of the Chernobyl Nuclear Accident, read the summary of the scientific consensus report at http://www.greenfacts.org/en/chernobyl/index.htm
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The most useful number I’ve found anywhere is the rule of thumb that your risk of dying of radiation-induced cancer is roughly 8% per sievert you’ve received. All other points of reference seem unnecessary once you know that.
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@GJNL
That report was subsequently withdrawn.
I very high reading was made and the worker who did so did the sensible thing and immediately evacuated along with other members of his team.
However this initial reading was not confirmed. When investigated, it turns out that this initial reading was incorrect and the actual figure was much lower.
This sort of action is exactly why the nuclear industry is so much safer than coal mining, drilling for oil, building off-short windfarms, etc. They are extremely overcautious.
In most lines of work the rule is that risk should be reduced until it is ‘As Low As Reasonably Practicable’ (ALARP). The nuclear industry reduces risks to well beyond ALARP, which is partly why it is much more expensive than it would be if we were willing to accept similar overall risks to other forms of power generation.
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The following HPA files may be of interest – they contain more data on radiation exposures:
* Physics of ionising radiation http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1194947419144
* Physics of ionising radiation (same title, different format) http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1194947317857
* hpa rpd 001 http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1194947389360
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Love this. I found the chart useful to put the topic of radiation into context. I have no background on this topic, and this helped me understand it a bit. Thanks you so much for creating it. I found the comments interesting.
Also… @Paul, your comments were interesting, but there came a point where they overwhelmed the beneficial nature of this post, making the the focus the argument rather then the topic. As a reader, I think the moderator made a good choice.
You seem knowledgeable, at least to a noob such as myself. Why not create your own chart rather then critiquing this one? Put your intellect and free time to a beneficial purpose. If you choose to do so, I for one would love to see how it compared.
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@linda
The chart has been picked up and diseminated widely. While Randall has added a disclaimer to the effect that it isn’t authoritative, it is being treated and described as such. In news articles citing the chart, the misleading information in it has indeed mislead. Creating my own chart doesn’t fix this.
The information I’ve posted four times that the moderator has suppressed is that in terms of radiation released the Japan incident is absolutely another Chernobyl. The only reason the population hasn’t been affected to the same extent is that most of the radiation has been blown out to sea. I.e. if the reactors were on Japan’s west coast instead of east coast, most of northern Japan would probably be uninbitable — at least for a few months if not indefinitely.
Comparison of Japan to Chernobyl is relevant to the comments because two people have, based on the chart, drawn the opposite conclusion. And the problem with drawing the wrong conclusion is the same problem I have with the chart: the safety or not of nuclear reactors should be judged on the unvarnished facts. Supressing facts or misleadingly representing them is a disservice. If done intentionally it is dishonest.
If anyone wants links to the Chernobyl/Japan information, they can ask the moderator to approve one of the comments I’ve posted with this information.
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How long does it take to cool down used plutonium rods?
There is information that it takes few decades. If that is true does it make any sense to try to cool them down by the sea water taking in account the amount of time needed. Some eminent nuclear scientists think the only solution would be to bury the reactors under the concrete as it has been done with Chernobyl’s one.
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Is anybody concerned about increased radiation levels caused by depleted Uranium? USA and NATO are using it right now in their invasion of the soveren state of Libya.
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This really helps to put things into perspective. I’ve read some of the arguments from people who have qualms about the chart, but I think they are relatively minor compared to the overall impact of the information displayed. Some of the time scales of the dosages may vary, but they are all noted.
The best part of this whole thing: The banana phone comment being left in when major news outlets repost this thing… lol
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Will sleeping with 2 other people double the radiation dosage from sleeping with one? Maybe that’s the problem with threesomes. 😉
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You’re in the news, mate.
http://index.hu/tudomany/2011/03/28/az_atomtol_nem_kell_felnetek_jo_lesz/
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@ViviWannabe
You seem knowledgable, so I don’t understand how you can think that you receive any radiation dose at all from an MRI scan. To make sure I was not deluded somehow, I looked it up and MRIs use NO IONIZING RADIATION. See:
http://en.wikipedia.org/wiki/Magnetic_resonance_imaging
So I don’t know what your vocational school could have been talking about. Are you sure it wasn’t from a CT scan? They do use ionizing radiation.
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Wait…
Does that mean that if you eat more than a million bananas a year, you will get cancer?
A roughly 120g per banana, and 365 days per year, that brings the total to about 328.75 kg bananas per day.
Don’t say you haven’t been warned!
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@Randall
Thank you, Thank you, and Thank you.
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I can’t say that I am impressed with the comparison of the day-dose near Fukushima with the lowest yearly dose linked to cancer. It is nice that the former one is still smaller, though. And you can still change to minute-doses if things get worse.
I also wish that someone would link some of the wild misinformation that I hear so much about. I saw some tabloids presenting correct information with tendentious graphics (like, say, radioactive warning signs as list items), but apart from some of the TEPCO statements, I did not see misinformation on the sites I seek out.
Quite on the contrary, people quite critical of nuclear plants pointed out immediately that the high readings of TEPCO were inconsistent AND explained the most likely reason for the error, something we will wait in vain to see from TEPCO or normal newspapers.
And, frankly, your “brb, reactor” story gives the impression that you think that the morale is “those hysterical people should not distract nuclear plant operatives” when it is clearly the responsibility of nuclear plant operatives to not respond to text messages when they have other duties.
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It is odd. I really liked this chart and I took it as a guide to asessing the real risk of information in the news rather than as a definitive scientific paper as some people seem to have interpreted it.
It seems to suggest caution but not panic and that you won’t die just because you come into contact with “radiation”.
I have also listened to the Material World podcasts on British BBC Radio 4 which also give an overview the 24th and 17th March are relevant http://www.bbc.co.uk/programmes/b006qyyb.
I didn’t realise for instance that the major cancer from Chernobyl was thyroid cancer *in children* and that Iodine-131 has a much lesser impact on adult populations.
Oh yes, and for those of you criticising the active safety of the reactor. Listen to the bits on newer designs.
As for the comments around mobile phones and cancer. People really need to get this in perspective. Getting cancer is like spinning a routlette wheel. Every day we spin a wheel with thousands of numbers on it, one cell might divide and become cancerous on that spin and might not be knocked out by our immune system. Consider that a red number and the other few thousand are black and safe. What you don’t want is the ball to land on the red, the more red numbers the worse your chances are.
So what adds reds. Genetics, smoking and eating processed meat are major factors. Drinking, eating and just about everything else are minor factors. It is quite likely that incredibly low doses of radiation and probably that even mobile phones might add some red numbers and cause cancer but they don’t statistically in almost all studies. What that means in reality is that of all the other things in your environment with similar low level impacts add together to make it impossible to pinpoint specifics. You cannot avoid them all, concentrate on the big ones and exclude them where possible and otherwise get on with your life.
If I was living in Japan I’d still be more worried about food, water, shelter and the possibility of another earthquake than radiation; although I would pay attention to official warnings.
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@esmeyny — reactor operators do not vanish in smoke when we leave work 😉 Sadly, we must do the irc equivalent when due in for work, same as the cashier at the grocery store.
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How could it be possible to compare Fukushima to Chernobyl with this chart? The given values for Fukushima are in 50km distance, somewhere where the wind doesn’t blow to, for Chernobyl “today near it” and “next to it exploding”, i.e. not comparable at all. (And the Fukushima accident isn’t over yet either.)
Today I read in the news that 1 Sievert (per hour) was measured on the grounds of the Fukushima reactors.
I wouldn’t want to live these 50km from Fukushima. The chart suggests that the dose (3.6mSv) is small compared to the “clearly linked to increase cancer” dose (100mSv). You need to do some calculations… 100 / 3.6 ~= 28, so if the situation doesn’t improve rapidly that dose is already reached in some two weeks. At the moment the situation doesn’t look like improving much though, more like barely keeping it from escalating. And every month you stay will give you the same dose again. If the wind doesn’t change and it gets worse. If you don’t get more by contaminated food.
Regarding cancer and spinning wheels – suddenly having a hundreds of times larger amount of red numbers should be worrying. And that the japanese have already enough to worry about, like food, water and shelter, makes the additional threat even worse, not less. The contamination also leads to even less food, water and shelter.
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Why is the massive amount of radiation contributed by tobacco overlooked? It’s arguably the most preventable source of ionizing radiation in our environment.
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@ Eddie
as I stated earlier that website http://www.epa.gov/rpdweb00/radionuclides/iodine.html seams to have a typo, the biological half life of iodine is 100 hours not days. http://journals.lww.com/nuclearmed/Abstract/2001/04000/Iodine_131_Ablation_Therapy_for_a_Patient.4.aspx
@ traffic
The dose for a bone barrow transplant patient is 10-12 Gy (or Sv to keep the same units). This would be a lethal dose it the patient did not get a bone marrow transplant.
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Do you have the chart in a scalable format, like PDF or SVG?
That would make it possible to print it at any size, which would be useful.
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Off topic, but relevant to today’s strip about HO Model Building: The model village in Bourton on the Water in the Cotswolds is a 1/9 scale model of the village that is, in fact, in the village, and so the model has a 1/81 scale model within it, which then has a 1/729 scale model within it. I think that’s as far as it goes.
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Paul,
You are an bigotomous zealot. The chart shows increasing doses of radiation, and then states to what such dose relates to: eg: this is an _anual dose_ , and this is a daily dose. Randall never claims anything else and your assumption that he should do it differenlty is entirely yours. Why don’t you draw your own chart and post a nice fat link in this forum ? Also, your complaints about censorship are wrong. Nobody prohibits you from making your own stuff and publishing it.
Have a nice day,
Mr. Oizo
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@ FrankH
I looked it up, and you’re right, it’s a CAT scan. I think my teacher just gave us the wrong term.
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