Talk:Chernobyl disaster/Archive 9

Europe uninhabitable.
Quote: If this mixture had melted through the floor into the pool of water, it was feared it could have created a massive steam explosion that would have ejected more radioactive material from the reactor. The Soviet scientific delegation estimated that only 1400kg of uranium and graphite mixture falling through into the pool could generate a 3–5 megaton explosion that would have razed Minsk, 320km from Chernobyl, and rendered Europe uninhabitable.

Is that really accurate? I don't believe that a steam explosion could level a town 320km away. Maybe it could irradiate it, but that's different. I searched for this, but all I found were forum posts. Bonus question: Could this happen at other nuclear plants or do they not have water underneath the reactor?--RaptorHunter (talk) 04:35, 8 April 2011 (UTC)


 * Accurate? Not at all. First, a 5MT blast wouldn't do squat at 320km - effects of a 20MT blast are limited to about 50km. Second, even the prompt fission of 1400kg of pure RBMK fuel (2% fissile) would release only 0.5 MT. A steam explosion driven by decay heat, far less. Lastly, even the release of the entire core inventory wouldn't render all of Europe uninhabitable. But hey, it was on the Discovery channel, it must be true! beefman (talk) 08:37, 8 April 2011 (UTC)


 * Agreed with User:Beefman - absolutely inaccurate. The blast effects radius in Effects_of_nuclear_explosions indicate you might get effects 50km away, but that's from a blast that's up in the air - a ground level explosion is going to be moderated, probably with much less in the way of blast winds and possibly less in the way of incendiary spread and so on. For your bonus question, there are other RBMK reactors still in use, yeah. Kate (talk) 11:38, 8 April 2011 (UTC)


 * OK, great. You can see my own answer to RaptorHunter's question at User talk:RaptorHunter. I couldn't make much sense of it myself but I thought it was worth putting up since it was said by one of the Soviet scientific delegation at Chernobyl, a nuclear physicist and missile scientist. That is, unless the translated voice-over was inaccurate (my Russian's a bit rusty), or unless they had an actor filling in for him.
 * I'm hoping those additions of mine will attract some good opposing evidence against scenarios like this, because there's a lot of information out there, from sources that seem like they should be reliable, that makes this article look overly optimistic and very incomplete. The first thing I did after watching Battle of Chernobyl was come to this article to find out how WP balanced up some of its claims, so that I could weigh the evidence for myself. But this article didn't even mention a lot of what was in the film, which wasn't very encouraging. Fuzzypeg★ 13:15, 8 April 2011 (UTC)

I've done a little more checking on Vassily Nesterenko and found that he was very much fighting the state to 'reveal the truth' about Chernobyl, that he apparently survived two assassination attempts and was at one point threatened with incarceration in a psychiatric asylum. I also read that he was one of the first up in a helicopter trying to get nitrogen (?!?) into the reactor, and the other two in the helicopter died soon after. I didn't think the scientific staff were doing liquidating. Sooo... just my speculation here, but two possibilities spring to mind: he was either the fighting a conspiracy of misinformation, or he was paranoid delusional. It's past 1 in the morning here, so I'm going to call it a night, but if anyone else can find more clear information on this guy, it would be great. At the very least we should clearly attribute that "vast explosion razing Minsk" to Nesterenko, since it seems he no longer speaks for the establishment, but is his own voice. Fuzzypeg★ 13:40, 8 April 2011 (UTC)


 * In my opinion, this sensationalist movie from the Discovery Channel is not a reliable source for the claim, which is quite clearly a ludicrous one. We would have to find a proper source for this or remove it. Alternatively, if the claim is itself notable we could record that, if there were adequate third party references. --John (talk) 19:54, 10 April 2011 (UTC)


 * The reason I included this claim in the first place is because it didn't come from the editorialising of the documentary (sensationalist or not): Vassili Nesterenko was looking into the camera, saying all this stuff (or I assume that's what he was saying, because I don't understand Russian, and was relying on the voice-over). While Discovery Channel may not in itself be a reliable source, I assumed that Nesterenko was. I now have some doubts as to how reliable he really is, but if he's been a thorn in the side of 'official' commentators on the Chernobyl disaster for years, then surely there will be information somewhere to discredit him as a source?
 * Nesterenko may well turn out not to be reliable as a source, but he is probably still notable as a prominent voice for doomsday scenarios and conspiracy theories. As such, it would be most valuable to keep his views in the article (even if relegated to a separate "crackpot theories"-type section) and clearly explain why he's wrong and why he's unreliable. That way the article becomes an antidote to this kind of misinformation. I came to this article trying to evaluate Nesterenko's claims and found no information on what the feared steam explosion might actually have entailed. All I could assume was that the article was incomplete, and possibly had its head in the sand. The simplest way I saw to provoke better information was to insert the information I had (from Nesterenko) and wait to see what other editors countered it with. Hopefully this process can result in better information for everybody. Fuzzypeg★ 22:34, 10 April 2011 (UTC)

I'm sorry, but this idea defies all logic. First, you ain't gonna get a 3-5 megaton steam explosion. The biggest conventional (non-nuclear) explosives on the planet are fuel-air explosives (FAEs) and, while formidable (and sometimes called "the poor man's atom bomb"), they don't make that big a boom. Second, even if you take all the reactor fuel at the plant, melt it, and mix it with the spent fuel from the SFPs, you ain't gonna have a sufficiently high concentration of fission-friendly isotopes to create a prompt-critical mass. Third (and fourth and fifth, etc.), there are all sorts of technical problems that would prevent a supercritical excursion in the short time you'd have before thermal forces spread the components apart and damped the reaction: moderators, fuel shape, control rods, air, water, etc. I'm sorry, but if this has to be included, it's gonna have to be really well sourced. We've gotta preserve our accuracy here; we're dealing with the reputation of the encyclopedia, here. &mdash; UncleBubba ( T @ C ) 20:07, 10 April 2011 (UTC)
 * The 3-5 megaton part was obviously wrong, but I am interested to see if it was possible for all of Europe to be contaminated by radiation from a steam explosion.--RaptorHunter (talk) 20:47, 10 April 2011 (UTC)


 * UncleBubba said: "even if you take all the reactor fuel at the plant, melt it, and mix it with the spent fuel from the SFPs, you ain't gonna have a sufficiently high concentration of fission-friendly isotopes to create a prompt-critical mass." — I thought that the whole reason for the original steam explosion that blew the top off the reactor was that the fuel assembly went prompt-critical. And according to this article, it is believed that a second, nuclear explosion followed a few seconds after the first steam explosion. Surely this was, then, a prompt-critical mass, and one composed purely from the normal fuel assembly weighing only 114.7kg? The doco says at one point that 195 tons (or tonnes?) of nuclear fuel were burning in the reactor by the time they were worrying about a second steam explosion. I presume that must have included spent fuel, and I don't know if that figure is correct; but this is a lot more massive than the 114.7kg that created the first prompt-critical mass. UncleBubba talks about insufficient concentration of fission-friendly material. Is that because spent fuel is too depleted to be formed into a prompt-critical mass, regardless of quantity/size or configuration? I'm just trying to understand this. Fuzzypeg★ 00:57, 11 April 2011 (UTC)


 * A typical RBMK-1000 core contains 190t of Uranium @ 1.8% enrichment = 3.4t fissile material (65 megatons if fully fissioned). A small portion of the fuel did go prompt critical during the accident - in the reactor before the meltdown. The contribution of this energy (vs. that of steam overpressure or H conflagration) to any explosion is debated but likely significant in my opinion. Once the fuel has melted, prompt criticality is highly unlikely though not impossible. beefman (talk) 08:28, 11 April 2011 (UTC)


 * How about if you take a large, roughly spherical blob of molten fuel and surround it with water, which acts both as a neutron moderator and neutron reflector? Might this achieve prompt criticality? According to Uranium-235 the nominal spherical critical mass for highly enriched 235U is 56kg, without need for any tamping or neutron reflectors (though as level of enrichment decreases, the required weight increases rapidly). Could 1400kg of UOX fuel in water go prompt-critical? Fuzzypeg★ 22:48, 13 April 2011 (UTC)


 * The critical mass does go up rapidly with falling enrichment, and is in excess of 2000kg at 2% (some sources say 1.8% for pre-Chernobyl RBMK fuel). Light water is a poor neutron reflector because it absorbs neutrons (unlike Beryllium, which is a neutron multiplier). A convex mass of RBMK UO2 submerged in water would not become critical. It's doubtful it would do so even with an ideal geometry, as 2% is around the limit for light water (why RBMK uses graphite). That's new fuel. Used fuel from the reactor would have an even lower fissile concentration and would contain fission products, which tend to be neutron poisons. So even straight UO2 wouldn't become critical, but of course in a fuel melt Zirconium and other materials go into the corium, reducing fissile concentration further. Finally, even if it a lump of corium did go prompt critical, it's very unlikely it could avoid blowing itself apart before more than a tiny fraction of the material could fission. This is has been a problem even in weapons designed to hold the critical mass together as long as possible. In fact, the maximum credible criticality accident did occur at Chernobyl 4, when the fuel was still in the reactor. See the 4th paragraph of this section. You can read more about criticality accidents here. beefman (talk) 03:50, 14 April 2011 (UTC)

Just to be clear exactly what was Nesterenko and what was editorial commentary, here is a transcript of the two relevant segments, the second containing segments of interview with Nesterenko and Gorbachev. I can only assume the voice-over translations for the interviews are accurate. First section (beginning around 3:00):
 * Narrator: "For the next seven months, 500,000 men will wage hand-to-hand combat with an invisible enemy: a ruthless battle that has gone unsung, which claimed thousands of unnamed, and now almost forgotten heroes. Yet, it was thanks to these men that the worst was avoided: a second explosion, ten times more powerful than Hiroshima, which would have wiped out half of Europe. This was kept secret for over twenty years by the Soviets and the West alike."

Second section (begins around 32:50):
 * Narrator: "The cement slab below the reactor core is heating up and in danger of cracking. The magma is threatening to seep through. The water the firemen poured during the first hours of the disaster has pooled below the slab. If the radioactive magma makes contact with the water, it could set off a second explosion even more devastating than the first. The country's top experts are called into action. Vassili Nesterenko was one of them. At the time, he was working on improving the Soviet Union's intercontinental nuclear missiles."
 * Nesterenko: "If the heat managed to crack the cement slab, only 1400kg of uranium and graphite mixture would have needed to hit the water to set off a new explosion."
 * Narrator: "The ensuing chain-reaction could set off an explosion comparable to a gigantic atomic bomb."
 * Nesterenko: "Our experts studied the possibility and concluded that the explosion would have had a force of 3 to 5 megatons. Minsk, which is 320km from Chernobyl, would have been razed, and Europe rendered uninhabitable."
 * Gorbachev: "We had to stop the process. If it continued, it would have been an enormous disaster. An enormous nuclear disaster."
 * Narrator: "This second explosion would have been accompanied by a terrible shockwave and a massive rise in radioactivity that would have claimed thousands of lives in a matter of hours."
 * Nesterenko: "Thank God it didn't happen. There were trains with over a thousand cars in Minsk, Gomel and Kiev, ready to evacuate the population."

Fuzzypeg★ 00:07, 11 April 2011 (UTC)

Having read a bit more material on Nesterenko, I don't believe he was paranoid delusional. He comes across as intelligent and well-reasoned. In this interview, for instance, he seems entirely lucid and internally consistent; he continued to associate with very highly respected scientists until his death. I have no explanation as yet for his statements about a huge explosion, but perhaps there was a translation problem (perhaps "razed" should have been "wiped out", as from from radiation exposure). I have queried UncleBubba's comments about the impossibility of a nuclear explosion, above; a nuclear explosion is the only way I can account for a blast of this size, though I still don't know quite how a steam explosion might trigger a nuclear explosion. I shall not speculate. I think it's important to note that even if such a nuclear explosion was impossible, that doesn't necessarily prevent the Soviet scientific delegation fearing that it was possible at the time, especially since they were working with limited information and heavy time pressures.

I am concerned that we are simply removing information from a notable and (presumably) reputable source on the basis of our own original research. This kind of information should stay in the article, and be balanced against opposing evidence (also from reputable sources) if there is opposing evidence. Wikipedia's role is to inform, not sweep under the carpet. Fuzzypeg★ 01:57, 11 April 2011 (UTC)


 * I guess you didn't see my earlier comment. The fears of this Nesterenko fellow may be reported as historically important (if they were) but not legitimate. So it seems recent TV documentaries are not acceptable sources here. Rather, sources contemporary to the event, showing the influence of Nesterenko's fears at the time, are required. I suggest the content sit here in talk until such sources are found. beefman (talk) 08:28, 11 April 2011 (UTC)


 * I don't believe that old (contemporary to the event) sources are better than newer sources. From memory, WP used to favour recent secondary sources; WP policies and guidelines have since been rewritten, and I can no longer find a guideline regarding age of sources. In normal academic research, newer secondary sources are generally preferred over older secondary sources. I do, however agree that the content should currently remain in talk, based on the old WP dictum that exceptional claims require exceptional support. We'll see whether Nesterenko's claims really are exceptional, and whether other support exists. Fuzzypeg★ 00:20, 14 April 2011 (UTC)


 * I guess my point was, his commentary is only notable if people acted on it at the time. A docudrama made in 2009 may not be the most accurate source of information on that. beefman (talk) 03:54, 14 April 2011 (UTC)

Clarifying Nesterenko's explosion scenario
Firstly, thanks to Beefman for patiently explaining the physics. Now, I have found a 2005 letter (in French) from Professor Nesterenko to Vladimir Tcherkoff, Solange Fernex and Bella Belbéoch, which describes the explosion scenario rather better than was explained in the documentary. My translation of the relevant section (with plenty of help from Google Translate) is as follows:
 * As the staff continued to pump water into the reactor with circulation pumps, water seeped into the reinforced concrete chambers below. A major risk arose: if the melt pierced the slab beneath the reactor and entered these chambers, it could create conditions for an atomic explosion. On 28-29 April 1986, employees of the Department of Reactor Physics, Institute of Atomic Energy, Academy of Sciences of Belarus made calculations that showed that 1300–1400 kg of mixed uranium-graphite and water constituted a critical mass and an explosion of a nuclear power 3–5 Megatons could occur. An explosion of such power could cause massive radiation injury to inhabitants in an area of 300–320 km radius (encompassing the city of Minsk) and all of Europe could find itself victim to severe radioactive contamination making normal life impossible.
 * I made a report on the results of these calculations on May 3, 1986 at a meeting with the first secretary of the CC, N. Sliounkov. This was my assessment of the situation that I explained at the meeting: the probability of an atomic blast was not great because at the time of thermal expansion the entire core had been shattered, and scattered not only within the reactor but throughout the whole industrial area surrounding the plant. They asked me why I couldn't give a 100% guarantee that no atomic explosion would occur in Chernobyl. I replied that it was necessary to know the condition of the concrete plate under the reactor. If the plate had no gap, crack or crevice, and if gaps would not appear later, then it could be said there would be no nuclear explosion.
 * One thing I know for sure: thousands of railroad cars were gathered around Minsk, Gomel, Mogilev and other cities located within a radius of 300-350 km from Chernobyl for the evacuation of people if such a need arose.

I think that's much more clear. He describes a nuclear blast, not a steam explosion, he explains that the critical mass would have had to be a mix of uranium and graphite surrounded by water, and he is clear that the radiation fallout, not the blast itself, would have severely affected Minsk. I still need to ask whether a mix of somewhat less than 1.8%-enriched uranium with neutron-moderating graphite could generate a critical mass when surrounded by water... Fuzzypeg★ 00:49, 15 April 2011 (UTC)


 * Thanks for that, Fuzzypeg. Mixed with graphite it's conceivable, but what's certain is that the blast could not be 3-5 megaton, but rather max 0.5 megaton as I calculated earlier. So something is still fishy, but if rail cars in Minsk were made ready then it is of historical importance. FYI, 14 tons (14,000 kg) would be about 5 megaton... beefman (talk) 04:07, 16 April 2011 (UTC)


 * As I already pointed out on the German discussion page de:Diskussion:Katastrophe_von_Tschernobyl, I guess that the most probable explanation is a scaling of the event by the amount of released radiation/fallout rather than by blast force. A 5 megaton pure fission explosion would be roughly equivalent to Ivy Mike test (which had a quite large fission fraction) plus the ejected material from the reactor and, depending on the size of the blast (probably far less than one kiloton), even from the neighbour reactors, spent-fuel depots etc. Although I doubt that the fallout of a 5-megaton fission event would render millions of square kilometres uninhabitable (then the whole Marshall Islands rather than the test area would be uninhabitable, too), in combination with the pulverized remaining reactur fuel, it could easily be an order of magnitude more. However, we definitely need more and reliable sources for that.--SiriusB (talk) 10:37, 19 May 2011 (UTC)

Yablokov et al. book
I have restored the mention of Chernobyl: Consequences in the lede section. The person who removed it gave the edit comment "Removed reference to "Chernobyl" book - this conclusions from this book are scientifically-flawed - this was not peer-reviewed information, and has since been discredited - please see Wiki page on book".

The whole range of scientific reports are controversial, with reports such as that by the UNSCEAR claimed to be scientifically flawed by expert commentators. This book is no different in that regard. While this book was not initially peer reviewed, two expert reviews were subsequently commissioned by the Oxford Journal Radiation Protection Dosimetry. These are probably the most reliable sources we have on the book. While the two reviewers had somewhat different conclusions, both considered it relevant and important to read within the spectrum of reports, in order to have an informed opinion.

The first reviewer, Dr. Ian Fairlie, gave a glowing appraisal. He noted only minor, non-critical omissions in it, and believed that it addressed important shortcomings in reports by western agencies such as the IAEA: specifically the western tendency to apply dose thresholds contrary to the linear no-threshold model, and their tendency to unnecessarily dismiss a large number of eastern epidemiological studies, excluding them by the application of overly-stringent double standards and scientifically unfounded challenges.

The second reviewer, Dr. Monty Charles, was more critical, but still believed the book important to read. He noted that many presented 'facts' were inadequately explained, that there was confusion or possible contradiction between certain figures, and that he personally was unable to assess the reliability of most of the source articles which the book drew on.

This is far from stating that the books conclusions are "scientifically flawed", and while Charles' statements may go some way to discrediting the book, Fairlie's statements go just as far, or further, towards discrediting its opposition, such as the UNSCEAR report!

In balance, this book seems no more controversial than any of the other major reports, and it seems to be regarded as notable in all the tertiary sources I've looked at; I say it stays in the article. Fuzzypeg★ 00:01, 9 May 2011 (UTC)


 * Perhaps I worded that wrong: it is more controversial than the other major reports, which are backed by various governments, the UN, etc. (And there are clear biases at work with those, such as the fact that all the UN- and WHO-related bodes are required to concur in their findings, and that the IAEA's stated purpose involves promoting nuclear power!) But the book has substantial notability and support, just as the big western agencies have many notable critics. The western agencies should get first mention, of course, but this book deserves mention as a notable dissenting voice. Fuzzypeg★ 00:38, 9 May 2011 (UTC)

Summary of immediate deaths, disaster's effects on human health--last paragraph of lede
Just restored the last paragraph of the lede, which was deleted in a sneak attack by an anonymous user on 4-12-2011. It accurately summarized the immediate deaths and section called "Assessing the disaster's effects on human health":


 * Russia, Ukraine, and Belarus have been burdened with the continuing and substantial decontamination and health care costs of the Chernobyl accident. Thirty one deaths are directly attributed to the accident, all among the reactor staff and emergency workers. A UNSCEAR report places the total confirmed deaths from radiation at 64 as of 2008. Estimates of the number of deaths potentially resulting from the accident vary enormously: the World Health Organization (WHO) suggest it could reach 4,000; a Greenpeace report puts this figure at 200,000 or more; a Russian publication, Chernobyl, concludes that 985,000 excess deaths occurred between 1986 and 2004 as a result of radioactive contamination. Apostle12 (talk) 08:15, 17 April 2011 (UTC)

Added sources for above paragraph, although they are completely sourced within the article itself. Apostle12 (talk) 00:41, 18 April 2011 (UTC)

The WHO figure there is for the immediate area and is not extrapolated across the entire area that was contaminated. 4,000 from heavy contamination in a small area, ~50,000 from lighter contamination over much of Eastern Europe and Russia.--Senor Freebie (talk) 15:27, 24 May 2011 (UTC)

This article praised
see Japan and the Future of Nuclear Energy approx 35 mnutes in scientist says this article is quite good. Geo Bard  Rap 21:26, 24 June 2011 (UTC)

Questioning the Standard Explanation
I ran across an article by Judith Pereira "Russian Design Reactors; A Different View on Chernobyl" in Nuclear Engineering International, p. Volume: 44 Issue: 534 Page: 27. (1999.01.31) In it, she quotes Dr. Konstantin Checherov of the Kurchatov Institute as questioing the official explanation. Checherov says that some operators reported something akin to an explosion 'before' the reactor was SCRAMmed, and of seeing the stars through holes in the roof. He also says that his investigations of the site indicate "it is clear that the explosion occurred 60 metres above ground, although still within the building. The overheating of the fuel elements due to coolant loss caused changes in pressure within the reactor which effectively ejected the core into the air where it exploded." Personally, I'm not qualified to discuss this, but it's interesting and appears in what I assume is a reputable publication (I found it in a Lexis/Nexis search, which is why I can't link to it, but I don't think they archive fringe material). I encourage someone better qualified than I to look at it and see if there's a place for it in this article. If so, I'd appreciate a quick note on my Talk page, since I don't get to Wikipedia nearly as often as I'd like these days: can't go from work, and when I get home I'm doing homework, not browsing the 'pedia.

* Septegram * Talk * Contributions * 01:20, 25 July 2011 (UTC)

Typo: critically accident.) under Fire COntainment — Preceding unsigned comment added by 80.216.171.111 (talk) 18:05, 20 September 2011 (UTC)

Edit request on 2 December 2011
Please change spelling from "Chernobyl" to "Chornobyl". Since the city is in Ukraine, the spelling should conform (not the Russian version).

174.115.204.226 (talk) 21:48, 2 December 2011 (UTC)

Not done: We use the common name in English which, according to the lazy Googlehits method, is overwhelmingly Chernobyl (20 million to 670000, if you're interested). More on the policy at WP:AT. --Old Moonraker (talk) 22:13, 2 December 2011 (UTC)

Distance between Forsmark NPP and Chernobyl NPP
In the article, it states the distance between Forsmark NPP and Chernobyl is 1,100 Km (680 miles) but according to Google Maps the distance between the two, as the birds flies, including great circle calculations, is 1,250 Km (780 miles). — Preceding unsigned comment added by 80.0.167.171 (talk) 22:19, 6 February 2012 (UTC)

Anyone able to verify?
Read some rumors that the first explosion was due to the Boron in the control rods being converted to Lithium. The lithium detonated in the water. Without any means of slowing the reaction, a steam and hydrogen explosion occurred next, taking the roof off.89.242.105.129 (talk) 03:37, 4 March 2012 (UTC)


 * I Don't think thats possible. To convert a significant amount of boron to lithium would require an exceedingly large number of neutrons, and the energy associated with the production of such a large number of neutrons would be vast - many orders of magnitude greater than was released. IE to make a kg of lithium you would need 100 grams of neutrons, or about 6 * 10^25 neutrons. If these neutrons originated in fission (which they would have to) then this amount of fission would release about 1.2 * 10^28 MeV or about 2 * 10^15 joules, or about half a megaton of TNT equivalent, which the explosion obviously was not (or it would have vaporised the entire area). Just roughly, since its estimated that the explosion was about 10 tons of TNT equivalent, that would mean the potential production of about 20 milligrams of lithium. 20 milligrams of lithium would not produce much energy if oxidised by water. I don't have the figure to hand but it would be a few joules compared to the 4 * 10^10 joules energy released in the explosion. Zwitt.the.twitt (talk) 15:35, 15 March 2012 (UTC)

Edit request on 2 January 2012
The first line of paragraph Evacuation Developements is: "The nearby city of Prypiat was not immediately evacuated after the incident, for the general population of the Soviet Union was not informed of the disaster until Monday, April 28, 2 days later, with a 20 second announcement in the TV news program Vremya."

This gives the feeling that the evacuation didnt take place until Monday, April 28, while the evacuation order was given (according to the same article) at Sunday 27, 14:00.

I believe that the paragraph should change to something like: "The nearby city of Prypiat was not evacuated until April 27, 14:00 more than 36 hours after the incident. The general population of the Soviet Union was not informed of the disaster until Monday, April 28, 2 days later, with a 20 second announcement in the TV news program Vremya." Edit made by User:46.103.183.150


 * Red information icon with gradient background.svg Not done: please provide reliable sources that support the change you want to be made. -- Bryce  ( talk  &#124;  contribs ) 05:40, 3 January 2012 (UTC)

i am not disputing any of the facts that the article present, I only say that the way they are presented might not make this facts clear so I am proposing a alternative presentation of the same facts. Edit made by User:46.103.183.150


 * Again, a reference to a reliable source needs to be provided. If we can Cite It, we can Write It. HarryZilber (talk) 18:47, 8 January 2012 (UTC)


 * http://pripyat.com/documents/informatsionnoe-soobshchenie-za-25-26-i-27-aprelya-1986-goda-o-vzryve-na-chaes.html - this documents is most probably done in earlier half of 28 april (it quotes 8am measurement but not any later). It claims that decision to evacuate the city was made at 27 april, and to the time of this document making almost all the population was evacuated. The very article claims later "The evacuation began at 14:00 on 27 April.", if this info was moved to the 1st senteence where Prypiat "regular life" been mentioned, it would be better. 79.111.192.141 (talk) 11:07, 28 March 2012 (UTC)

This part does not make sense
Under the Experiment and Explosion section, the following statement is made. "A bigger problem was a flawed graphite-tip control rod design, which initially displaced coolant before inserting neutron-absorbing material to slow the reaction. As a result, the SCRAM actually increased the reaction rate in the lower half of the core."

Why would a graphite tip, which was only inserted [as part of a rod] 1/3 of the way down, create an increase in reaction rate in the lower half of the core? — Preceding unsigned comment added by 89.242.101.103 (talk) 07:46, 16 March 2012 (UTC)
 * Because graphite is moderator: it slows down the neutrons. And fast neutrons that used to fly-through the fuel turned into the slow neutrons that were captured by fuel causing the fission. Think about why that graphite all around was needed at all. 79.111.192.141 (talk) 11:18, 28 March 2012 (UTC)

Date of promotion to good article?
I see that the article was delisted from Good Article status on May 7, 2006. When was it promoted to Good Article status? This date would help readers looking for a better version of the article.--Wikimedes (talk) 19:58, 25 March 2012 (UTC)
 * The article was listed as a GA on 8 March 2006 (diff 1, diff 2). The version of the article at the time of promotion: 04:24, 8 March 2006 (the next edit was a revert of an unsourced edit). At the time, articles did not have to pass through a nomination process to be listed as GAs; individual editors could assess articles and list them as GAs at their discretion. --Muchness (talk) 13:01, 26 March 2012 (UTC)
 * Thanks. — Preceding unsigned comment added by Wikimedes (talk • contribs) 05:54, 27 March 2012 (UTC)

Edit request on 28 March 2012
In the section concerning the Chernobyl Shelter Fund, it is stated that the New Safe Confinement (NSC) is expected to be completed in 2013. According to the link provided, as of 2011, the NSC is expected to be completed in the summer of 2015. Please change "The NSC is expected to be completed in 2013" to "As of 2011, The NSC is expected to be completed in summer 2015". http://www.ebrd.com/pages/news/press/2011/110408e.shtml

Getmeagator (talk) 20:19, 28 March 2012 (UTC)
 * Done. --illythr (talk) 21:20, 28 March 2012 (UTC)

Sabotage?
I have been studying this incident for a while now. Anatoly Dyatlov ordered the reactor to be dropped to 200MW, knowing this would poison the reactor in violation of instruction.
 * Actually, he *rised* power to 200MW - http://accidont.ru/data01.html - so he was de-poisoning the reactor. And it contributed to the disaster, as we know now in the hindsight. Was the reactor heavily poisoned, it would just halt by itself.

This manufactures a situation where he could call for all but 6 of the control rods to be removed. This leaves the reactor in a state where it is controlled by coolant only.
 * why so ? he could remove more rods and he could insert back those rods. And it only was about human-controlled rods, while there still were many computer-controlled rods, that acted on their own.
 * "Reactivity reserve", while measured in rods, is not about actual nubmer of rods inserted, it is virtual coefficient, calculated by computer for about 10 minutes, and showing if reactor is in economically rentable mode. http://accidont.ru/ozr.html

Given the positive void coefficient, the obvious outcome to any trained professional would be that a drop in coolant, such as when the turbines are shut down, will result in an uncontrolled power increase.
 * By laws, there is no such allowed by design thing as fast uncontrolled power increase. Professionals tend to trust laws.

I really can't see how this is accidental, especially given the objections that were made at the time. Did Anatoly Dyatlov try to blow up the reactor? — Preceding unsigned comment added by 89.242.101.103 (talk) 09:41, 16 March 2012 (UTC)
 * ...and became suspect #1 ? Very silly action. But at least he did not blow Ignalina station in 1983 and Saints-Peterburg station in 1975, did he ?79.111.192.141 (talk) 11:35, 28 March 2012 (UTC)


 * More likely is that he had a defective situational awareness and didn't consider steam voids and reactor poisoning occurring at the time. That he removed that many control rods to full height implies a lack of comprehension as to what was going on inside of the reactor and unapproved procedures.Wzrd1 (talk) 00:02, 3 April 2012 (UTC)
 * Partially true. At that point no one thought that reactor may blow, if that is prohibited by laws, so he did not question the manuals, like we would do today (having benefits of his sad experience). As about poisoning - reducing power - posioned reactor is shutting down. It is not making it potentially blowable - it is making it potentially halting. Non-poisoned reactor would just blow faster. So to make it brief: 1) No major vialoation of procedures ghappened. 2) Minor violations could not lead to disaster to the best of practical knowledge of that time. 3) in practice, minor violations are inevitable, Italian strike. Afterall, the general constructor, that ordered the experiment, had withdrawn from the planning of this 3rd (or already 4th?) attempt, which is also violation i think. 4) Anyway, the topic is about sabotage - willing and reasoned action to break the device. I think we can render this conspiracy out completel. 79.111.192.141 (talk) 22:28, 9 April 2012 (UTC)

Russian publication
'Russian publication, Chernobyl, concludes that 985,000 premature cancer deaths occurred worldwide between 1986 and 2004 as a result of radioactive contamination from Chernobyl.

I am not opposing using this in the article, but I think it is too weak to include in the lead. It has been heavily criticised as unscientific  and at the very least  is a very controversial report. This cannot be presented with due weight in the space afforded within the lead. AIR corn (talk) 03:37, 21 March 2012 (UTC)


 * I have expressed my concern before that said report is WP:FRINGE. I am going to edit the last sentence of the lede to read "Greenpeace, among others, have made far higher estimates." -- Limulus (talk) 08:09, 21 March 2012 (UTC)
 * I don't think it is fringe. Well-known physicist Amory Lovins has called the Chernobyl book "an authoritative analysis based on 5,000 mainly Slavic-language scientific papers" . We should try and capture the diversity of opinion in the lead, per WP:Lead. Reverting. Johnfos (talk) 10:28, 21 March 2012 (UTC)
 * I don't think we should capture the diversity of opinion in any articles lead, particularly ones covering controversial subjects. We should present the most reliable information possible in the lead and use the body of the article to explain the more extreme views. This is simply a matter of WP:Undue. Presently in the lead the Russian publication is given the same wieght as the WHO estimate, even though it has much less mainstream support. As far as diversity goes the Greens, Greenpeace and the Union of concerned scientists already have reports mentioned in the lead. They should definitely get a mention, but this much is probably undue for them as well. So even without the Russian publication we have three anti-nuclear organisations in the lead and one neutral organistion all with roughly the same weight. AIR corn (talk) 03:07, 22 March 2012 (UTC)
 * You're citing a "well-known physicist" on matters of epidemiology? This sounds like an appeal to authority. Please review the Chernobyl: Consequences of the Catastrophe for People and the Environment article. I think it does a fairly good job of summing up why Consequences is of dubious merit, i.e. fringe. -- Limulus (talk) 11:22, 21 March 2012 (UTC)
 * No appeal to authority. Just noting that Lovins has seen value in the publication and I have provided one of his many sources for that. Others have also seen value in the publication and it cannot be simply dismissed. WP:Lead says that the lead should “summarize the most important points — including any prominent controversies”, and that is why the publication needs to be mentioned there. I notice that the article on the book does not use the term "fringe". What reliable source uses the term "fringe" to describe the publication? Johnfos (talk) 14:03, 21 March 2012 (UTC)
 * The descriptor fringe is from the Wikipedia policy WP:FRINGE I mentioned previously. From the Consequences lede: "The book was not peer reviewed by the New York Academy of Sciences. Four reviews were published in the academic press, with three of them considering the book severely flawed and contradictory, and one praising it. The review by M. I. Balonov published by the New York Academy of Sciences concludes that the value of the report is negative, because it has very little scientific merit while being highly misleading to the lay reader. It also characterized the estimate of nearly a million deaths as more in the realm of science fiction than science." (emphasis added) The uncritical inclusion in the lede of these claims which "depart[s] significantly from the prevailing or mainstream view in its [...] field" is in direct opposition to policy: "editors should be careful not to present the pseudoscientific fringe views alongside the scientific or academic consensus as though they are opposing but still equal views. While pseudoscience may in some cases be significant to an article, it should not obfuscate the description or prominence of the mainstream views." If you insist on including mentions of Consequences in the lede, please find some way of bringing it into WP:FRINGE compliance or I will find it necessary to add Template:Fringe theories to the article as I do not want to engage in WP:EDITWARRING. -- Limulus (talk) 16:42, 21 March 2012 (UTC)
 * Wow, some very extreme stuff there -- a real fringe-busting effort! Johnfos (talk) 14:08, 22 March 2012 (UTC)
 * Fringe is a loaded term, but the Russian publication is the weakest of the sources used in the lead and definitely leans towards a fringe view. It makes claims orders of magnitude bigger than other reliable sources, has been heavily criticised by most scientists (a big one is for being a meta-analysis that has cherry picked its studies) and is only getting serious support from scientists with a strong POV against nuclear energy. Probably worth mentioning in the body where it can be presented neutrally, but it should not be given prominence in the lead. AIR corn (talk) 03:04, 22 March 2012 (UTC)
 * Thanks for explaining that so well, and so calmly. Unless someone else weighs in with a view to the contrary, I will go along with what you have said. Johnfos (talk) 14:08, 22 March 2012 (UTC)
 * I have added it back. The extremely wide range of estimates is critical here, because the plain fact is that no one knows the ultimate impact of the Chernobyl event.  To arbitrarily label the Russian publication "the weakest of the sources used"  (according to whom?) is artificial.  If we are going to eliminate the "high" number, should we not also eliminate the "low" ("32" and "64") numbers?  The Chernobyl report may in fact be flawed, just as all the sources are undoubtedly flawed; that is the point of this paragraph.   But the fact remains that this report is based on the work of thousands of reputable scientists; it cannot be arbitrarily dismissed without skewing the article.  The reason for the much greater numbers cited in Chernobyl is that the scientists involved broadened their focus to include the entire planet; that is hardly an extreme or "fringe" approach.  Citizen monitoring of radiation levels following the Fukushima event confirm that the impact of such events is global--ready access to monitoring equipment in 2011 (as opposed to 1986) made such monitoring possible. Apostle12 (talk) 09:17, 31 March 2012 (UTC)
 * I backed down previously, but really think Apostle12 has made some good points, so am reinstating his edit. Johnfos (talk) 00:50, 1 April 2012 (UTC)
 * Thanks. I truly believe that it's a better lede with mention of this report.  We are not promoting it, only informing the reader of its existence and underscoring the uncertainty of our present state of knowledge. Apostle12 (talk) 04:56, 1 April 2012 (UTC)
 * As the consensus has altered, with it has evaporated the justification for my RV.--Old Moonraker (talk) 06:55, 1 April 2012 (UTC)

The point is being missed. Not all sources are equal and undue means we must take that into account. It does not warrant the same amount of space in the lead as the WHO report. AIR corn (talk) 10:00, 3 April 2012 (UTC)
 * I disagree. It would be difficult to further reduce mention of Chernobyl without rendering it meaningless.  There is no POV pushing or underwriting associated with its mere mention.  Please keep in mind that the World Health Organization (WHO) is known to most readers, hence no context is required.  The point is not to suggest equivalency among the various sources, only to underscore the broad spread among various estimates. Apostle12 (talk) 10:22, 3 April 2012 (UTC)
 * How about just saying "Publications from Green and other advocacy groups have put the estimated deaths between 25,000 and 985,000." after the WHO sentence. That works as the lead author of the Russian publication is a co-founder of Greenpeace in Russia. That conveys the range without violating undue. AIR corn (talk) 10:35, 3 April 2012 (UTC)
 * I can see that the extremely truncated version you wish to promote matches your own POV. I think the current version is a far more appropriate expression of NPOV.Apostle12 (talk) 11:08, 3 April 2012 (UTC)
 * WP:Undue is part of NPOV. AIR corn (talk) 12:24, 3 April 2012 (UTC)
 * BTW I left a note at the Fringe theories/Noticeboard about this, asking about how much wieght should be given to the publication. AIR corn (talk) 10:37, 3 April 2012 (UTC)
 * Will look forward to hearing the opinions of others, though I have noticed that the "fringe" label has been widely used of late in attempts to skew, or even eliminate, several Wiki articles. Apostle12 (talk) 11:11, 3 April 2012 (UTC)

Edit request on 26 April 2012
'The general population of the Soviet Union was not informed of the disaster until ' should be changed to 'The general population of the Soviet Union was not informed of the disaster until Monday, 28 April, 2 days later' as there seems to be a mix up in the section 'Monday, 28,, 2 April days later'.

Marinechris (talk) 11:59, 26 April 2012 (UTC)
 * changed sentence to The general population of the Soviet Union was first informed of the disaster on the 28 April, 2 days after the explosion, with a 20 second announcement in the TV news program Vremya. AIR corn (talk) 12:12, 26 April 2012 (UTC)

Death estimates?
It seems a little odd that most of the figures featured in the article's first paragraph for estimates of the number of long-term deaths appear to be from rather biased sources, many of whose reports have been criticised for being poorly carried out or not properly peer reviewed. Do people really think it's appropriate to give these figures such prominence, in a way which implies they are all as reliable as each other, and without mentioning the problems with them as is done later in the article? 90.199.218.232 (talk) 19:29, 3 April 2012 (UTC)
 * Not everyone. See the section titled "Russian publication" above. AIR corn (talk) 21:09, 3 April 2012 (UTC)
 * ALL of the referenced reports have been criticized for their biases--both those that are obvious underestimates and those that may be overestimates. The point of the paragraph is that no truly reliable figures exist. We simply do not know. Apostle12 (talk) 21:39, 3 April 2012 (UTC)
 * You have Greenpeace, the Greens and a publication written by the founder of Greenpeace in Russia, which are all have anti-nuclear biases. Then there is the world health organisation and the united nations, which are neutral. While they have all been crticised some are more reliable than others. We can not present them all with equal weight in the lead. AIR corn (talk) 22:00, 3 April 2012 (UTC)
 * Your assessment of "neutrality," especially with respect to the World Health Organization report (linked in the article), represents your own bias. The most saliant criticism of the WHO report is that it leans in the direction of "social harm reduction," since many experts consider the psychological impact of Chernobyl (victim identification, hopelessness, lifestyle hazards) to be more severe than the physical dangers from exposure to longterm low-level radiation.  Thus the tendency of the WHO report is to focus, in a rather myopic way, on immediate transient hazards and to minimize longterm health effects caused by exposure to low-level radiation. However understandable, this represents a politicization of the data, not unlike what occurred in France after the Chernobyl disaster, where the Ministry of Health arbitrarily declared all French agricultural products to be "safe" in order to ensure their marketability and avoid a financial debacle.  Biases come in different colors and flavors; to pretend that any source, including the United Nations, is free of bias is not credible. Apostle12 (talk) 22:59, 3 April 2012 (UTC)
 * Sure, there are valid criticisms of the WHO and United nation's report and they belong in the article. Just like the other estimates with there criticisms also belong. The lead however is a different beast. It should summarise the content, giving appropriate weight to each point. A report written by Greenpeace does not have as much weight as a report written by WHO. Having three separate anti nuclear estimates in the lead is WP:Undue. Our bias's don't matter, that is simple fact. AIR corn (talk) 23:28, 3 April 2012 (UTC)
 * Disagreed. "Small" and "independent" does not mean "fringe". What matters is qualification and expertise. Slapping stickers "anti-nuclear" is not an argument. Dissenting opinions from reputable people are routinely recorded everywhere. WP:Undue dose not mean the big organization may overwhelm everybody else. On the other hand I agree that a long list of estimates in the intro make no sense. I suggest the following formula in the intro "WHO gives an estimate of xxx deaths, while other sources give numbers of excess deaths in range of  yyy-zzz". Staszek Lem (talk) 01:49, 4 April 2012 (UTC)
 * Potential for bias from sources also matters. That is why conflicts of interest are declared in reputable academic papers. Greenpeace has an obvious conflict and, intentionally or not, that affects their research. WHO does not have the same conflict and is more reliable. The more reliable source should get more weight, size has nothing to do with it (although Greenpeace is far from small). Anyway I am all for keeping it simply in the lead, although we should somehow indicate who the "other sources" are. "WHO estimates that the death toll could reach 4 000, while Greenpeace and other sources give numbers of excess deaths in range of 25 000-985 000" AIR corn  (talk) 02:36, 4 April 2012 (UTC)

Repeated assertions that no conflicts of interest exist in the WHO report and that this report is more scientifically reliable do not make it so. The short formula suggested is inadequate, because it does not underscore the fact that Chernobyl.. is talking about excess deaths worldwide, as opposed to deaths that may occur in the immediatley affected area. The existing paragraph is clear and will confuse no one--the body of the article is the place to elaborate as to the limitations of the various sources--their different foci, the possible political agendas of the authors, their tendencies to distort in various ways. As written, the last paragraph of the lede is accurate, well-sourced and balanced. Apostle12 (talk) 05:22, 4 April 2012 (UTC)

I think it would give a much better assessment if the first paragraph did not mention any actual figures, but instead just gave an overview of the problems of obtaining an accurate estimate (perhaps mentioning problems with the linear no threshold model that the estimates currently given use). Just giving a small sample of some of the wildly varied estimates gives a misleading impression, as most readers will not read on to the more detailed explanation later in the article. 90.199.218.232 (talk) 12:38, 4 April 2012 (UTC)
 * That's not a bad idea. Estimates by their nature are always going to be problematic. AIR corn (talk) 13:33, 4 April 2012 (UTC)


 * I agree completely that it would be a good idea to provide readers with an overview of the problems associated with accurately estimating the number of deaths caused by the Chernobyl disaster. There are four main categories of mortality: immediate (within the first three months), short term (within the first five years), long term (within thirty years), and extended term (within a set number of generations). Each category requires the collection of scientific data, proper assessment of that data, and objective reporting, both of the known facts and those facts that cannot accurately be determined.
 * The first problem has to do with accurate data collection. Data collection for the purpose of scientific analysis has been highly politicized since the beginning of the nuclear era, with the United States, the Soviet Union, the United Kingdom and France insisting on outright censorship; it is telling that the four original nuclear powers chose areas far removed from centers of power to conduct their above-ground testing of nuclear weapons, and all invoked "national security" as justification for keeping their respective publics uninformed.  With respect to the effects of WWII detonation of nuclear devices in populated areas of Japan, absolute censorship prevailed for at least seven years, and partial censorship followed.  Continuing to the present (including the Fukushima Daiichi disaster) all governments have worked to conceal facts and block scientific observation and analysis. Some governments have been more responsive to constituent needs than others, however no government has been forthcoming, and no government (or collection of governments) has the ability to deal effectively with the ultimate ramifications of nuclear contamination.
 * With our enhanced ability to detect the presence of nuclear contamination--beginning with Chernobyl and especially following Fukushima Daiichi--we have entered an era where accurate data collection, independent of governmental control and censorship, finally becomes possible. We know that all significant discharges of nuclear by-products into the atmosphere become global events that have health consequences, and we are just beginning to be able accurately to assess those health consequences, including mortality.
 * Since the issue of "pro-nuclear" vs. "anti-nuclear" has entered these discussions, I should disclose that a close family member was a primary physicist/chemist with the Manhatten Project, and he worked for decades in related research endeavors. The consensus in our family was that anti-nuclear sentiment was rooted in ignorance.  My own understanding has evolved over the past fifty years, and I would now classify myself as neither "pro-nuclear" nor "anti-nuclear."  Rather I am in favor of full disclosure of the facts and full acknowledgement of our collective ignorance.
 * I think it would be best to include a general statement that will provide readers with an overview of the problems associated with accurately estimating the number of deaths caused by Chernobyl, AND to provide representative low-range to high-range estimates, however "wildly varied" they might seem. Far from being "misleading," such estimates accurately convey to readers how little we really know at the present time.Apostle12 (talk) 20:16, 4 April 2012 (UTC)


 * Your reasoning appears to be based on WP:OR, we should be quoting the ranges that the most reliable sources quote, that is all. If any reliable sources dicuss any issues with the figures then a section on it may be justified, if the text has WP:DUE weight. IRWolfie- (talk) 09:49, 8 April 2012 (UTC)
 * Of course. This is the place where editors can legitimately discuss things based on a variety of factors.  I would never propose adding an OR discussion to the article;  we would need impeccable sourcing to discuss any issues related to estimated death figures.  Please note that all of the death figures that currently appear in the lede are sourced, and more extensive discussion of these figures appears in the main body of the article. Apostle12 (talk) 11:37, 8 April 2012 (UTC)
 * The best way to determine what weight to use for figures is to see what the latest academic publications use. Our information here should reflect the way they describe these figures. AIR corn (talk) 00:11, 9 April 2012 (UTC)

How about this for the last paragraph in the lead. "Russia, Ukraine, and Belarus have been burdened with the continuing and substantial decontamination and health care costs of the Chernobyl accident. Estimates of the number of deaths potentially resulting from the accident vary enormously. Thirty one deaths are directly attributed to the accident and an UNSCEAR report placed the total confirmed deaths from radiation at 64 as of 2008. The World Health Organization (WHO) estimated that the death toll could reach 4,000 among the 600,000 people subjected to the highest radiation doses. This number is based on the Linear no-threshold model and has been criticised by various organizations as being too low. Publications from environmental and science advocacy groups have put the estimated deaths resulting from the accident between 25,000 and 985,000." AIR corn (talk) 06:06, 13 April 2012 (UTC)
 * I would like to say "yes" for a change, however I don't think this really works. In particular, I think we need to find a sourced discussion of the various ways (immediate, short term, long term and multigenerational) to consider mortality.   And we need to provide some sourced figures to go with those different ways.  What you have written muddies the waters more than it clarifies anything.  I don't even know what "environmental and science advocacy groups" means. Apostle12 (talk) 06:58, 13 April 2012 (UTC)
 * The Union of Concerned Scientists and Greenpeace are describe here as a advocacy groups while the European Greens (TORCH) and Greenpeace are generally considered environmental. There may be a better way to describe them. I don't think we want to get into too much detail in the lead. The sourced discussion on effects at different stages would fit in better in the body. Theoretically we shouldn't use information in the lead that is not in the body. If anything at this stage I would like to add a sentence on the environmental impact than more about the human toll. AIR corn (talk) 07:19, 13 April 2012 (UTC)
 * I guess we could just say Publications from the European Greens, Greenpeace, the Union of Concerned Scientists and other individuals have put the estimated deaths resulting from the accident between 25,000 and 985,000. AIR corn (talk) 07:31, 13 April 2012 (UTC)
 * "Other individuals"? Chernobyl..draws on over 1,000 published titles and over 5,000 internet and printed publications discussing the consequences of the Chernobyl disaster.Apostle12 (talk) 19:40, 13 April 2012 (UTC)
 * Disagree; please note UCS ref states: "The UCS analysis is based on radiological data provided by UNSCEAR, and is consistent with the findings of the Chernobyl Forum and other researchers." Lumping UCS with Chernobyl:Consequences is inconsistent with WP:UNDUE -- Limulus (talk) 09:07, 13 April 2012 (UTC)
 * What exactly do you disagree with? The UCS report is six times higher so how can it be consistent with UNSCEAR? As at the start my ideal solution is still to omit the Chernobyl report from the lead altogether and just mention it in the body, but this seemed like a possible compromise. AIR corn (talk) 10:44, 13 April 2012 (UTC)

I think Limulus is on the right track. The section called "Assessing the disaster's effects on human health" needs to be cleaned up and perhaps expanded. At present it is very poorly written, with the result that the last paragraph in the lede is similarly unclear. The main article, "Chernobyl Disaster Effects" http://en.wikipedia.org/wiki/Chernobyl_disaster_effects, is also a jumble. We have no hope of getting the lede right if the larger discussions are fatally flawed, which I believe they are.

Also I think we need to avoid phrases like "based on the Linear no-threshold model" (suggested by Aircorn above); this is an encyclopedia article written for lay readers. Language that is either too technical, or overly broad, reduces clarity.

I notice that our discussion here mirrors the state of confusion that exists globally regarding this topic. We know very little, and what we do know tends to be distorted in attempts to further various political agendas. Apostle12 (talk) 20:08, 13 April 2012 (UTC)
 * Linear no-threshold model can be linked so that should help with understanding. However we could just use the description This number assumed that damage is directly proportional to the absorbed dose and has been... BTW I agree with fixing up the section in the body. So many citation needed tags and it jumps all over the place. However, I think most of the relevant information is there so we can still come up with a decent lead. Like the ip said above, many people will only read the lead. AIR corn (talk) 21:26, 13 April 2012 (UTC)


 * From ref "Why was the Chernobyl Forum’s estimate of 4,000 excess cancer deaths so low? The estimate only pertains to a much smaller subgroup of people who experienced the greatest exposure to released radiation, and therefore significantly underestimates the total number of cancers and cancer deaths that will be attributable to Chernobyl. The effects of the radiation were not limited to the highly contaminated areas in Belarus, Ukraine and Russia – they were felt in less-contaminated areas in those countries as well as in Europe and beyond." The point is that they are using the same data and apparently similar methodology. In contrast, Chernobyl:Consequences is... well, it's page does the talking. In terms of being constructive, would this be acceptable? The TORCH report and the Union of Concerned Scientists countered with estimates in the tens of thousands. Greenpeace and others have made estimates in the hundreds of thousands, although these have been severely criticised. -- Limulus (talk) 20:39, 13 April 2012 (UTC)
 * I see what you mean. That is much better than what I had. AIR corn (talk) 21:26, 13 April 2012 (UTC)
 * I made some changes that are intended to clarify the differing sampling scales (600,000; hundreds of millions; billions), and I qualifed Chernobyl.... I haven't seen the Greenpeace report criticized to same extent as Chernobyl...,  so it may be unfair to lump the two together. I acknowledge that there are numerous flaws, both with respect to the methodologies used and its sourcing, however Chernobyl does have its defenders--in particular Chernobyl... is the only report that makes a serious attempt to quantify the global impact of radioactive contamination resulting from the Chernobyl disaster, which is why I would argue for its continued inclusion.  Apostle12 (talk) 22:07, 13 April 2012 (UTC)
 * Based on your comment, I am going to tweak the current wording from: "Though some of its methodologies have been criticized, a Russian publication, Chernobyl, concludes..." to "The Russian publication Chernobyl, which has received criticism for its methodology and sourcing, concludes..." -- Limulus (talk) 01:47, 14 April 2012 (UTC)
 * Thanks Limulus. I think what you wrote is a big improvement.  Apostle12 (talk) 08:26, 14 April 2012 (UTC)

There is still one sentence in the lede that doesn't read as smoothly as I would like. "Estimates of the number of deaths that will eventually result from the accident vary enormously; these disparities reflect both the lack of solid scientific data and the different methodologies used to quantify mortality - confined to specific geographical areas or worldwide, and immediate, short term, or long term." I may have another go at it; do think it's on the right track. Apostle12 (talk) 08:26, 14 April 2012 (UTC)

Just completed another tweak. I think the lede looks pretty good now. Aircorn, Limulus...how is it looking to you? Apostle12 (talk) 08:41, 14 April 2012 (UTC)
 * It hasn't addressed any issues relating to undue weight. AIR corn (talk) 17:02, 14 April 2012 (UTC)

Why have only these numbers been used? All of the estimates used in the first paragraph have been based on the linear no threshold model, which has been subject to criticism. Why not mention other assesments like this (can't paste the link for some reason: google Allison Wade, Oxford, "safety of nuclear radiation..." etc). You mention how little we know about this, so lets put criticisms like this in alongside the larger estimates to emphasise that. 90.199.218.232 (talk) 20:22, 15 April 2012 (UTC)
 * Did Allison Wade speak specifically of Chernobyl? If so you could add a section to the main body of the article mentioning his criticism of the linear no-threshold model. However this article is not the place to debate micro-dosimetry or other factors that Wade does not consider in his writings.  If Wade offers specific criticism of the larger Chernobyl estimates, and especially if he offers a smaller estimate, this number could find its way into the lede. Apostle12 (talk) 20:33, 15 April 2012 (UTC)
 * The main focus is on a discussion kf methods of determining the impact of radiation on human health, but this is put in the context of Chernobyl towards the end of the piece, and an estimate totalling 84 excess deaths (due to radiation) is given. 90.199.218.232 (talk) 21:01, 15 April 2012 (UTC)
 * I would encourage you to add Wade's perspective to the section of the main article titled "Assessing the disaster's effect on human health." I would be curious to see which deaths Wade ascribes to Chernobyl; I assume he limits these to immediate and short-term considerations of mortality, which is consistent with his thesis. Not sure we could successfully integrate into the lede references to the debate concerning the linear no-threshold model, however the figure itself could be mentioned.  And perhaps Wade's criticism of the linear no-threshold model could be described in lay terms. Perhaps something like:  "Nuclear expert Allison Wade disputes that longterm exposure to low-level radiation is harmful to human health and calculates 84 excess death directly attributable to the Chernobly disaster."  Question:  Does Wade include in his analysis excess deaths that we know statistically will eventually occur due to thyroid cancer?  While highly treatable, such cancers do recur with known regularity and there is little doubt the resultant deaths will be attributable to Chernobyl.  Apostle12 (talk) 22:19, 15 April 2012 (UTC)
 * Heres the link http://www.google.com.au/url?sa=t&rct=j&q=allison%20wade%2C%20oxford%2C%20%22safety%20of%20nuclear%20radiation&source=web&cd=7&ved=0CE4QFjAG&url=http%3A%2F%2Fwww.physics.ox.ac.uk%2Fnuclearsafety%2FARTICLE.pdf&ei=5TmPT5v6E-W5iQe5nqDNDA&usg=AFQjCNFemFoXhPwtoxj3v7wMO3szudGT5Q . It opens up a PDF. He is not the first person to question the LNT model in this way.. In fact in the scientific literature there appears to be more reports that think the 4,000 figure is an overestimate due to the use of this model than an underestimate. I have not found any scientific papers that use the tens of thousands or hundred of thousands numbers. There are a few that use the 4,000 number though.[. This is the measure of due that we should be aiming for. [[User:Aircorn|AIR corn ]] (talk) 22:26, 18 April 2012 (UTC)


 * The problem with the national academy Chernobyl book is that most of the studies have not been properly conducted, with improper scientific technique (no or improper allowance for confounding factors) which makes it of little scientific use. Thousands of non scientists could publish papers on a subject but that would not outweigh a single properly conducted study which passes the review of respected peers because its been properly conducted. The book under discussion has been lambasted by highly respected scientists everywhere, but are there any highly respected scientists recommending it? This whole discussion seems broken from the start since the book has absolutely no respectability at all. Lack of controlling for alcohol, tobacco, drug use, and a host of other factors simply turns the book into junk.


 * Also of relevance, the latest research has started to track down a non linearity in the response of human cells to radiation which implies that the LNT is wrong at low dose rates. In case youre not aware of it, heres the link. I believe it has significance for this topic. http://lowdose.energy.gov/pdf/2011/PNAS.pdf Zwitt.the.twitt (talk) 18:53, 1 May 2012 (UTC)


 * Writing encyclopaedic articles on controversial topics is a challenge. If this was to be published in a respected peer-reviewed academic journal then there would be no question about not including the Greenpeace, Union of concerned scientists or Russian publication estimates. Unfortunately this is not a scientific publication so non-scientific reports do have a place. How much place should still in a large part be decided by reviews in reliable sources. A paragraph in the lead devoted to scientifically questionable estimates falls outside of WP:DUE. I think a RFC is in order. AIR corn (talk) 06:23, 4 May 2012 (UTC)


 * The Greenpeace article and the Union of concerned scientists reports do appear in peer reviewed articles. not uncritically, but then even the TORCH rpeort and Chernobyl forum reports do not appear uncritically. To say these are excluded outright and suggest they are fringe is just not a true reflection of the current academic debate. Even so, there are some clear criticisms of those reports, which is the on thing Chernobyl disaster effects does alright at getting across.
 * Moreover, the constant assertion in favour for UN and WHO reports is disingenuous. These cannot be said to be entirely neutral sources in the face of 'clearly biased' Greenpeace or other sources.(One can base ones report on peer reviewed sources, but there's no guarantee there's no cherry picking going on). Moreover, the IAEA which was involved in the Chernobyl Forum Report has an explicit role to encourage the peaceful use of nucelar energy: How is that not a bias? -- Cooper 42(Talk)(Contr) 17:02, 4 May 2012 (UTC)

The Bhopal disaster page, though not excellent, gives an indication of what could be done here. Indeed, the section below the section on deaths in the page here is also good. Estimates vary. Emthodology for deriving those estimates varies too. It should be the job of this page to get across: As briefly as possible (and here I do not think the debates around the linear model need to be in the introductory section). Asides from clearly WP:Fringe reports, the best struture is the format of: "the estimated number of deaths varies from X (as per A) to Y (as per B) to Z (as per C)" Greenpeace and even the flawed "Chernobyl" report are not arguably fringe. It is, quite simply, that there is no definitive answer to "how many were killed because of Chernobyl": even within the scientific, peer reviewed work on the subject there is no clear consensus. Partly this is an epidimiology issue, partly this is a bias issue, a sampling issue (etc. etc.). The best Wikipedia can do is to report this range from reliable sources, this is not the place to start making judgements about "which number is the right one". Getting across the level of uncertainty is a reflection of the current debates (within and out of academia) Finally, WP:COI: I have been studying Chernobyl and the Zone for 4 years straight (PhD).-- Cooper 42(Talk)(Contr) 17:02, 4 May 2012 (UTC)
 * 1) That estimated deaths vary
 * 2) Depending on source
 * 3) That such variation depends upon models, measurement and assumptions.
 * Unless you are cititing your own works, there is no WP:COI. Surprize: in addition to amateurs and dilettantes, professors are allowed to edit wikipedia as well, and non-apologetically, too. Staszek Lem (talk) 21:39, 4 May 2012 (UTC)
 * Yep, assumed that. But snarky users have used me being actively engaged in researching a topic and not mentioning it as a reason to start edit wars in the past...-- Cooper 42(Talk)(Contr) 13:39, 5 May 2012 (UTC)
 * I am just talking about the lead, which should summarise the whole article not focus overly on one section (three paragraphs on the human impact, one vague sentence on the environmental). I am more than happy for someone who is researching a topic to contribute. Could you provide some links to recent journal articles that review the human impact? I am not coming from a pro-nuclear angle, but a pro-science one and have not seeing anything in the scientific literature to support the Greenpeace and other reports. AIR corn (talk) 19:30, 5 May 2012 (UTC)

I'm gonna dump this here as one of the more recent reviews to give an idea of the kind of dicussion within epidemiology / physics publications; it specifically takes on the "Yabloklov et al." / NY Academy of sciences and the UNSCEAR publications. I think this is open access, so this link should work. but I'm not certain so I've quoted below. . This is from ARCH-Agenda for Research on Chernobyl Health. and editorial within Journal of radiological protection (2011) vol. 31 Issue 1:

This review, same publication, the Journal of Radiological Protection is a book review of the UNSCEAR report. . ''Book review: Health Effects Due to Radiation from the Chernobyl Accident. Annex D of UNSCEAR 2008" by Monty Charles (2011) Journal of Radiological Protection:

And so, I think, the kind of uncertain, ambivalent relationship that is had with the non-peer reviewed and even the UNSCEAR and Chernobyl Forum reports is indicated. This is of course a tiny selection, but both are review pieces and so help illustrate a point. Here the end of that ARCH editorial from above is salient:

Clearly there's clearly a more nuanced and ambivalent relationship to the publications than simply outright ignoring them. Although, this is part of an editorial of a proposed project to look at the health effects of Chernobyl, so highlighting the possible 'unknown' effects is part and parcel of getting the funding needed. Other writers, especially Ivankov and those associated with the UNSCEAR paper simply ignore the Greenpeace publication outirght. There are only degrees of bias and total NPOV is rare; whether looking for cash or supporting ones own research results, academic papers are still not totally NPOV...

Apologies about the text-dump. But I think it gets the point across; Greenpeace sourced and other reports are dealt with by the academic literature. Not uncritcally; there are many reservations about them. At the same time the UNSCEAR report is not the 'holy-grail' of all answers. Questions remain unanswered, the 'most accurate' estimate of deaths is a major contention and there is a dearth of decent peer-reviewed publications in western literatuer on the issue menaing that - carefully, with due caution and a critical eye, sometimes publications with clear bias or from unpublished data must be taken into consideration.

TL;DR version: The best Wikipedia can do?
 * Contentious reports (unpublished data, biased sources) are still used by academics, albeit with a cautious approach and critical eye.
 * The UNSCEAR report has not given the final word on the subject.
 * There is a decent amount of uncertainty as to the correct modelling methods.
 * Report as clearly and succinctly as possible that estimates vary from different sources and, though there are reasons to be sceptical about certain sources, there is no consensus on the matter.-- Cooper 42(Talk)(Contr) 14:15, 6 May 2012 (UTC)
 * Thanks for that. I will have more time to look over it this weekend, but that will help a lot. AIR corn (talk) 07:28, 8 May 2012 (UTC)
 * Too bad we can't say "Estimates of the death toll vary so greatly that most of them must be wildly inaccurate." :) It might be a good idea for the lede to mention the confirmed deaths in one paragraph and the estimates in another, instead of the current scheme where each are spread across 2 paragraphs, overlapping in one paragraph and the confirmed deaths also overlapping the paragraph mentioning cleanup and environmental impact.  (I tried to do this just now but got into an edit conflict.  Probably better to discuss first anyway.)  Longer term it might be better for the lede to mention the number of confirmed deaths, a range of estimates (and perhaps a summary of the disparate methods), and have a table near the top showing the number of deaths of each estimate and the estimator, and perhaps the methods used in the estimate, if they fit.--Wikimedes (talk) 19:23, 17 May 2012 (UTC)

Blatantly bogus numbers
This:

"nearly a million premature cancer deaths occurred between 1986 and 2004"

= blatantly bogus.

The global collective dose from Chernobyl was around 0.6 million person-Sieverts as determined by the UNSCEAR.* Aside from such as the few heroic and daring individuals who unfortunately got acute radiation poisoning, additional mortality per person-Sievert can not be very high. If it was, there would be an actually noticeable statistical increase in cancer when, for example, an individual gets 0.25+ Sievert (250+ mSv) extra radiation exposure on average over a 50 year period by moving from the United Kingdom (under 2 mSv/yr natural radiation) to Finland (above 7 mSv/year average natural radiation exposure to its populace).**

For instance, when that Chernobyl publication claims a million additional cancer deaths occurred, for such to be the case from 0.6 million person-Sievert would be like claiming on the order of a 70% chance of an extra cancer death per 0.4 person-Sievert exposure. Yet Finland, where each person gets 0.4 Sievert extra natural radiation exposure on average over a lifetime, compared to the U.K. populace, does not accordingly have most of its population dying from cancer. Rather, Finland actually has lower cancer mortality, both unadjusted or adjusted by relative populations over age 65, than the United Kingdom.*** Obviously there are other influences too, other differing factors between countries, but such still provides vastly more than enough of an upper limit to rule out the preceding absurdity.

The Union of Concerned Scientists, by the way, is a misleadingly-named group where absolutely anybody can register just by paying them a small signup fee. One blogger easily successfully registered his dog as a demonstration. Their only real membership requirement is having a credit card.

[*] http://www.iaea.org/Publications/Magazines/Bulletin/Bull383/boxp6.html

[**] http://funk.on.br/esantos/doutorado/ARTIGOS%20AEROGAMA/papers%20sem%20catalogar/491.pdf

[***] http://old.eurohealth.ie/overview/finland.html vs http://old.eurohealth.ie/overview/uk.html — Preceding unsigned comment added by 12.74.176.190 (talk) 18:07, 16 May 2012 (UTC)


 * Please disregard this post. Wikipedia is not a forum to carry out research of Chernobyl disaster or criticism of such research. If you have any published references which contradict the statement you don't like, then we will discuss them. Staszek Lem (talk) 01:54, 17 May 2012 (UTC)


 * I agree with Staszek. This subject is highly controversial, and various factions will always consider the viewpoints of other factions "bogus." Our job is to represent the main published viewpoints, which, to a remarkable degree, this article does.Apostle12 (talk) 02:34, 17 May 2012 (UTC)

Re 'Experiment and explosion'
A small part of this section sounds confused and I believe whoever wrote it did not quite understand the details.

'A second, more powerful explosion occurred about two or three seconds after the first; evidence indicates that the second explosion resulted from a nuclear excursion.' - the first explosion resulted from the nuclear explosion, the cause of second explosion is disputed. Since a significant amount of the core was ejected in the first explosion it seems unlikely that a second nuclear excursion happened, but still possible. However the paper cited does not IMO suggest this. I think all it is doing is calculating the total power of the nuclear excursion(s).

'However, the ratio of xenon radioisotopes released during the event indicates that the second explosion could be a nuclear power transient. This nuclear transient released 40 GJ of energy, the equivalent of about ten tons of TNT. The analysis indicates that the nuclear excursion was limited to a small portion of the core.'

Theres no way of knowing if the xenon was released during the first or second explosion. They are talking about the total xenon release in that paper from what I can tell. How could they differentiate between xenon released in the first explosion and xenon released 3 seconds later? They could not. Hence they calculate that a total of about 40 GJ of energy was released an in excursion around the same time that the reactor split open and the xenon was released (it had to be released at this point or its isotopic ratio would have been changed). The ratio of xenon isotopes indicated that it originated in a small part of the reactor which underwent a severe power excursion (this can be calculated from the isotopic ratio). If the isotopic ratio observed had been generated in the whole of the core mass then the total explosive yield would have been much larger than it was (from damage observed). Hence only a small part of the core could have been involved.

So it seems to me that all that paper referenced shows us is that about 40 GJ of energy was created by a brief nuclear fission reaction which happened just prior to the xenon being released (which we know was when the reactor exploded) (by definition this must be a power excursion).

I think the text should be changed to indicate that about 40 GJ / 10 tons of TNT equivalent of nuclear heat was created in a power excursion which caused the reactor to explode. Unless theres some other evidence that the second explosion was caused by a second power excursion then this reference should be removed. Zwitt.the.twitt (talk) 17:21, 15 March 2012 (UTC)

The paragraph beginning "There is a view" should be omitted -- it contains only speculation which is unsupported by evidence and thus cannot contribute to understanding the event. — Preceding unsigned comment added by 24.167.248.251 (talk) 21:40, 8 May 2012 (UTC)

This is the biggest fabricated lie of the 20th century and it never really happened — Preceding unsigned comment added by 119.225.47.6 (talk) 06:50, 4 June 2012 (UTC)