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Tag: safety

How to get professionals to agree with your opinion

…or…

How the Canadian Center for Policy Alternatives used nurses to lie to the government.

Surveys and questionnaires are a simple and effective way of gauging people’s opinions. The result can then in turn be used to influence the opinions other people hold, most often to become opinions you want people to have.  And the more supposedly trustworthy the people you survey are, the greater you can expect the compliance to be.

Let me show you an example of this. This is a TV advert from 1949.

Simple enough isn’t it? If many medical doctors like this brand of cigarette, it must be really good, right? Right! Doctors can’t be wrong. Moving along…

Surveys and questionnaires that you make yourself have a nice bonus: you can make them any way you want. The advantage of this is that if you phrase the questions just right, you can get any answer you want.

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Study says German nuclear power causes child cancer… or does it?

A German report (summary) on cancer incidence seems to indicate that there is a higher frequency of cancer cases, mainly leukaemia in children, around nuclear power plants in Germany. The report was written at the Federal Office for Radiation Protection in Germany and based on two articles [1, 2].

The report was quickly embraced by the Swedish movement against nuclear power (SNF, Schlaug) and has also created a few headlines in Swedish newspapers (AB, HN).  These newspaper articles claim that people living in the vicinity of Swedish nuclear power plants are worried by this report. Lars Barregård at the Centre for Medical Enviromental Sciences wants to investigate the incidence of leukaemia around Ringhals nuclear power plant. However, he says to HN:  “…the radiation levels are very low and should not be able cause an increase in cancer frequency, though a study can be good to lessen the worries“. (translated from Swedish)

The Swedish Radiation Safety Authority (SSM) however does not consider it important to perform another study in Sweden as such studies have already been conducted with consistent negative results. A study in 1995 found no increase in numbers of cases of leukaemia. Also the number of cases of child leukaemia has been more or less constant at around 60 cases per year over the past 30 years, a period of time which includes the gradual phase-in of nuclear power in Sweden. SSM states that further epidemiological studies trying to blame cancer on nuclear power are not needed. Instead, there is a need of a larger knowledge base and more studies that tries to find the underlying reason for child leukaemia in general [6].

Still this leaves us with the German report. Does it give us due cause to worry? Not really, because in the conclusion of the report, the authors state:

…the present status of radiobiologic and epidemiologic knowledge does not allow the conclusion that the ionising radiation emitted by German [nuclear power plants] during normal operation is the cause.

What this means is that in order for nuclear plants to have caused these cancers, there must be some completely unknown effect in play; some kind of cause that science does not know anything about yet.

They further note that…

This study can not conclusively clarify whether confounders, selection or randomness play a role in the distance trend observed.

…and…

…these estimates are rather inconclusive because they are based on a very small number of cases

This means that they have not been able to rule out that other factors may explain the results, factors such as: carcirogens unrelated to the nuclear plants, errors in the study, or pure chance due to the amount of data being much to small.

Reading further we find that they have not measured the level of radioactivity around the plants or even include any kind of estimate of this:

This study is not able to state which biological risk factors could explain this relationship. Exposure to ionising radiation was neither measured nor modelled

One amusing interpretation of this would be that closeness itself, and not radiation, is a cancer causing agent. That is to say being 100 meters from a non-leaking plant would be more dangerous than being 200 meters from a wrecked one, because distance is what they have looked at, not radiation.

This is perhaps not odd concidering that radiation is not significantly or even measurably higher around these plants. The report concludes (again) that radiation cannot be a factor in this study on account of the additional exposure from nuclear powerplants being staggeringly small.

Annual exposure in Germany to the natural radiation background is approximately 1.4 mSv and the annual average exposure through medical examinations is approximately 1.8 mSv. Compared to these values, the exposure to ionising radiation in the vicinity of German NPPs is lower by a factor of 1,000 to 100,000. In the light of these facts, and based on the present status of scientific knowledge, the result of our study cannot be explained radiobiologically.

A far more serious thing to be remarked is that the second article notes that the study goes against findings of other studies made previously [2]:

….this observation is not consistent with most international studies, unexpected given the observed levels of radiation, and remains unexplained. We cannot exclude the possibility that this effect is the result of uncontrolled confounding or pure chance.

Looking at French studies [4,5], similar to the German one, we see that they indeed could not find any significant relation between cancer incidence and absorbed dose or closeness to a nuclear power plant.

Further reading reveals that they have not been able to process data considering children moving around prior to the cancer notice, nor the importance of lifestyle or whether the time the children spend in their homes is of relevance.

All of this summed up leaves us with a report that in effect states: “We think there might be slightly more cases of child cancer around some nuclear power plants, but we don’t really know why. And in order for the nuclear plants to be the actual cause, instead of something else, 60 years of radiobiological science must have completely missed something here”.

This notwithstanding the Swedish self-proclaimed enviromental movement beats the big drum and claims that it would be “irresponsable to concider constructing new nuclear power plants before it is clear whether children that live around existing plants suffer from conditions like leukaemia more often than the general public” (translated from [3]).

At Nuclear Power Yes Please we find this kind of alarmism to be just as irresponsible. We do not oppose performing epidemiological studies on nuclear power plants because science, openness of information and continuous review is one of the pillars that support our confidence in nuclear power. If anything we would welcome an exhaustive, well conducted study that settles the matter once and for all so we can either go happily about our lives, or get to work on a solution should one be needed.

But to spread fear of nuclear power among the general public without a solid scientific reason is reprehensible, especially with a report that even by its own words state that the results are vague, inconclusive and goes against most previously made scientific studies.

In light of the movement bringing this up just as there are huge political shifts in the view on Swedish nuclear power, possibly lifting the three decade old ban on building new nuclear power plants, we at Nuclear Power Yes Please are left to wonder what the real cause of the alarmism is. Why is the movement against nuclear power bringing this up now? Is it a genuine worry about public health, or is it a desperate attempt by the movement to try to justify their anti-nuclear stance? If it is the latter, we cannot express enough our outrage at such reckless abuse of science in order to try to make a political point.

1: Peter Kaatsch, Claudia Spix, Renate Schulze-Rath, Sven Schmiedel and Maria Blettner. Leukaemia in young children living in the vicinity of German nuclear power plants.

2: Case–control study on childhood cancer in the vicinity of nuclear power plants in Germany 1980–2003. Claudia Spix, Sven Schmiedel, Peter Kaatsch, Renate Schulze-Rath and Maria Blettner.

3: http://www.naturskyddsforeningen.se/natur-och-miljo/aktuellt/?news=7104

4: M.L. White-Koning, D. He’mon and D. Laurier et al.. Incidence of childhood leukaemia in the vicinity of nuclear sites in France, 1990–1998.

5: A.-S. Evrard, D. He’mon and A. Morin et al., Childhood leukaemia incidence around French nuclear installations using geographic zoning based on gaseous discharge dose estimates.

6: http://www.stralsakerhetsmyndigheten.se/Om-myndigheten/Aktuellt/Nyheter/SSM-Tysk-studie-ger-inga-nya-ron/


News articles:
Tysk forskarrapport som borde oroa

Blog entries:
Kärnkraft, barncancer och sannolikhetskalkyler
Ett (o)sannolikt ställningstagande av Centern
Barnleukemi, kärnkraft och Maud Olofsson

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The Forsmark incident was not Chernobyl

This is the second blog response to a blog entry made by The King of the country Lagom. The previous entry dealt with his claims that opinions are sacred and how one must not speak up against them. This entry will deal with the purely factual errors of his claims about nuclear power.

The King of Lagom claims that an incident that took place in 2006 at the Forsmark nuclear power plant could have escalated into a Chernobyl-type accident.  Well… first he says that, and then he says it could have become something entirely different. If this sounds confusing it is because the King of Lagom probably doesn’t quite know what he’s talking about but rather builds this statement on misconceptions about what actually happened at Chernobyl and Forsmark respectively. So let’s examine the incidents and compare.

The 1986 Chernobyl accident

April 26, 1986. The night shift at reactor 4 at the V.I Lenin Nuclear power plant, 20 km north west of the town of Chernobyl, Ukraine, has been ordered to do a test. Due to operator error, they accidentally poison the RBMK-type reactor which makes it almost grind to a halt. They don’t know why the reactor is giving so little power though because they were mostly coal plant workers, inexperienced with nuclear power, and oblivious to things such as nuclear poisoning. The shift boss, determined to finish the test, gives orders to proceed, telling the operators to perform actions that go against several operating rules of the reactor. This puts the reactor in an unstable state.

When the test is finished and they shut down the reactor, a fatal flaw in the reactor’s control system causes the reactivity to spiral out of control, making it output between ten to onehundred times normal thermal effect. The water in the reactor flash boils and the enormous steam pressure blows the building apart. A few seconds later a chemical explosion, when water that has been split into hydrogen and oxygen burns, rocks the complex again. The reactor is on fire for ten days, resulting in a large plume of radioactive fallout.

There are several factors that allowed this accident to happen.

First it was operated by poorly educated personnel, in a political system where safety came second. In the Soviet Union, you did not rise to attractive jobs like this one by being good at your craft but by kissing up to the communist party. Also you did not stay at jobs like this by speaking up against safety issues, because such things made the party look bad. For instance this particular test was supposed to have been run years ago when the plant was commissioned. But since it failed back then, it had to be done again, this time in secret from the Soviet nuclear regulatory authorities.

This shouldn’t have been a problem. But the second reason the accident could take place was the deliberate violations of the operating rules of the reactor. The test was to have taken place when the reactor was outputting at least 700 MW; they started when it was at 200 MW. They were not allowed to withdraw more than a certain number of control rods; they withdrew almost all of them. They were not allowed to increase water flow in the reactor past a certain amount when operating at low power; they did. They were not allowed to disengage the safety systems that would have shut down the reactor when they did any of the aforementioned; but they did indeed disable them.

All of this made reactor come into an unstable state that let its most critical design flaw come into play: the positive void coefficient. The void coefficient is a quality in a nuclear reactor that tells us what happens when it gets too hot. When coolant boils in a reactor that has a positive void coefficient, the nuclear reaction increases. This makes the reactor hotter, which makes more water boil. This speeds up the reaction more, making it even hotter… and so forth. And not only was the void coefficient in the RBMK-reactors of the Chernobyl plant positive, it was also dangerously high.

Finally, because the reactor had no real core vessel, nor any concrete containment, the force of the explosion wrecked the building completely. A fire started in the hundreds of tons of graphite that was in the reactor. Also the building itself that was supposed to have been made from fireproof material, was not, and the debris caught fire as well.

This is what is known as a criticality accident, when the nuclear reaction goes out of control. In this case it produced so much heat that the entire reactor blew up from all the thermal energy. This accident was not a nuclear meltdown.

The 2006 Forsmark incident

July 27, 2006. At the switch-yard for Forsmark-1, an electrical arc causes a short circuit which leads to the unit being disconnected from the power grid. This is serious as the plant relies on power to keep all pumps going.

If a nuclear reactor does not have working pumps, eventually the cooling water in the reactor will boil away. If that starts to happen you must engage the emergency core cooling, reserves of water kept for this very purpose. If this too fails and the reactor boils dry, the heat can be such that the reactor core becomes damaged, popularly called a meltdown. This can happen even when the nuclear reaction has been stopped because decay heat continues to be produced a few hours after a reactor is shut down as very short-lived nuclear waste falls apart. This is what happened at Three Mile Island in 1979.

So when a nuclear plant becomes disconnected from the power grid, the reactor is shut down and on-site diesel generators start to provide power for the pumps to deal with the decay heat, and this was what happened at Forsmark 1. However in this case, two out of the four diesel generators did not start, disabling two safety trains out off four. But the two remaining diesel generators were more than enough to drive the pumps. Hence the reactor was cooled and emergency core cooling was not necessary. The reactor shutdown proceded normally.

Similarities?

No, there are no similarities between these two incidents. The Chernobyl disaster was the case of a criticality accident that caused an extremely violent explosion that completely wrecked the reactor core; the building it operated in; burned for days. The Forsmark incident was the case of  slight degradation of safety features while the reactor and its cooling operated normally. The cooling system was operational the whole time; the emergency cooling did not need to be engaged; the reactor core was not damaged; the reactor tank was in no way threatened; the over one meter thick reactor contaiment remained perfectly safe. And fire? Naw… there is no graphite in Forsmark-1. Water handles that job instead.

So when the King of Lagom says that the Forsmark incident could have become another Chernobyl, he is wrong. There is no way that Forsmark-1 or any of the other Swedish nuclear reactor could undergo the process that led to the explosion in Ukraine in 1986. And this is not just because we employ people that know what they are doing; care about safety first; follow procedure; don’t do things behind the back of the nuclear regulatory authorities. No, the most important reason why a Chernobyl-type criticality accident cannot happen in Sweden is the reactors themselves. Because unlike the RBMK-reactors of the Soviet Union, our boiler- and pressurized water reactors do not have a positive void coefficient. We did it the opposite way, so that when water starts boiling in the reactor, the nuclear reaction slows down because of inescapable laws of physics. It’s nature’s own choke collar on nuclear reactions.

Conclusion

The RBMK-type of reactor was employed only in the Soviet Union. The international community is working hard to get the twelve RBMK’s that are still in operation closed. Even though I’m a nuclear friend I’m not an idiot, and as such I am very glad that one of the remaining RBMK’s. Ignalina-2, will be shut down in 2009, meaning that Lithuania no longer operates them. Now we just need to get Russia to shut down theirs and we’ll finally be rid of this blight.

When discussing nuclear safety, anyone that uses Chernobyl as an example of what could go wrong in nuclear reactors is ignoring reality. The BWR/PWR reactors of the world hold about as much in common with the RBMK-design of the Soviet Union as does slavery to common work; as does forced child soldiers to commissioned adults. There just is no comparing them as they operate differently down to subatomic level.

The Forsmark incident was not, and could not have become, another Chernobyl. This is not an opinion, it is physical reality.

/Michael

ADDENDUM: As I posted a link to this entry in his blog,  and called him on his Ad hominem attacks, he first approved the entry, then he cencored it and claimed that I was violating his right to have “free opinions”, i.e. he doesn’t want anyone telling him he’s wrong.

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