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Matt Strassler's failed attempt to mask his antinuclear activism

The strong March 2011 Tohoku earthquake and tsunami were brutal and caused 16,000-20,000 deaths. If I borrow a term used in the Obamacare, they have also caused some glitches in the Fukushima One Nuclear Power Plant which, despite the hype in the media, haven't killed a single person. Two workers had radiation burns and 37 people have suffered non-radiation physical injuries.

This outcome of a 9.0 magnitude earthquake that failed to cause any casualties (so far) despite its scariest possible interplay with a 42-46-years-old nuclear facility is a testimony of the wonderful safety that nuclear energy brings.

The cleanup efforts were expensive and led to some concerns which suggest that Japan isn't the best place for nuclear power plants (and that there are perhaps cheaper ways to get energy such as fracking) but to present the outcomes of this "experiment" as anything else than a clear victory for nuclear energy is just plain dishonest. That's what I am strongly convinced about.

In his blog post suggestively titled

The Mess at Fukushima, and The Need for a Scientific Lens,
Matt Strassler modestly complains that he cannot find a single "trust-inspiring" weblog about nuclear engineering that would be as wonderfully objective and professional as his weblog about particle physics. Ehm. He announces that he wouldn't tolerate any peer-unreviewed comments and he would edit and delete most comments, anyway. And indeed, he does add unflattering disclaimers in front of the first comment by trained industrial and chemical engineer (Gastón E. Nusimovich).

Thankfully, at an invisible place inside this would-be objective blog post, those who don't skip texts in parentheses do learn what Matt Strassler thinks about nuclear energy:
Polemical diatribes will be deleted; activism for or against nuclear power is inappropriate here [I happen to oppose nuclear power in its current form, but that's beside the point right now].
Well, it's clearly not beside the point if Matt Strassler himself wrote a demagogic antinuclear rant that leading Greenpeace demagogues wouldn't be ashamed of. His antinuclear prejudices penetrate every sentence of the text – but this bias may still look invisible to many naive readers. That's a creepy combination.

Let me discuss some of the reasons why I consider Strassler's blog post to be a piece of a dirty antinuclear propaganda and that his comments about impartiality are both hypocritical and revealing Strassler's fundamental misunderstanding of the inner workings of the industry and the human society.

The first part of the title calls the complications in Fukushima "mess" which is marginally OK but still emotional. The second part of the title is arguably worse; it suggests that science isn't in charge of nuclear energy in Japan and in charge of the cleanup efforts.

After several would-be balanced comments about the events in Fukushima, we may witness the first assault against TEPCO:
And the worries about a variety of possible risks from the plant have been growing, especially because the clean-up at the plant is still run by TEPCO, which has engaged in repeated cover-ups and poor decisions... not to mention the fact that it’s a power company, not a nuclear accident site cleanup company.
OK, so TEPCO is guilty of "repeated cover-ups and poor decisions". Still, they haven't caused a single death, despite the difficult challenges, so even if we allow the word "a lie", this vitriolic conspiracy-theory-like accusation is surely missing some beef. And may I tell you something? Much of what's happening in their company is their internal business and they have the right to "cover it up".

The comment that TEPCO isn't a nuclear accident site cleanup company is really cute. As far as I know, there don't exist any specialized yet independent nuclear accident site cleanup companies. The reason is the following: nuclear accidents are both extremely rare, extremely expensive to fully solve, and extremely dependent on the technology of particular nuclear facilities.

That's why it has been the normal expectation that the companies running the nuclear power plants are the main source of nuclear safety experts as well as the cleanup experts whenever needed. Specialized nuclear accident site cleanup companies would get a contract so rarely (especially if several such companies would be competing) that they would go bust or they would depend on a huge amount of borrowed capital.

It's just silly to propose specialized nuclear accident site cleanup companies. Matt Strassler may boast that he only wants see the best world quality weblog about nuclear engineering but if he were able to reproduce at least the common sense of an average educated man, it would be a huge leap forward for him.

The folks in TEPCO know the technical issues in the power plant more than everyone else. The reactors were supplied by GE (1,2,6), Toshiba (3,5), and Hitachi (4) but it's such a long time ago that the real experts can't be found in those companies. The real experts are those who were working with these reactors in TEPCO. It's the normal state of affairs and by his complaints about this common-sense arrangement, Matt Strassler only proves that he doesn't have a clue about basic things related to management, capitalism, law, international relations, and the world in general.

His next sentence goes even further:
I find it extraordinary that the situation hasn’t been put into the hands of a blue-ribbon international panel of nuclear scientists and engineers, with full power to make decisions and with full transparency for all to see as to what is going on.
It's not extraordinary, it's common sense, too. There are at least three reasons (plus one summarized reason that I will add as a bonus) why Strassler's idea about the international panel hasn't been realized:
  1. Japan is a sovereign country and none of the problems in Fukushima have international proportions or global implications
  2. Japan is a high-tech country and especially when it comes to their own reactors and their own health concerns and population, they're more well-informed, competent, and motivated to act wisely than anyone else
  3. International organizations such as the U.N. have so far only been able to construct low-brow ideologically driven panels of pseudoexperts and they wouldn't be helpful at all
  4. Strassler's "international panel" idea is spherically idiotic – it is idiotic no matter what direction you look at it
Let me add a few words about each of the points above.

First, Matt Strassler already "spiritually" lives in a global totalitarian society with a Big Brother who can intervene anywhere and with no good justification, who can take care of the Japanese enforcement forces whenever he wants, who may dictate evacuations, an international bureaucrat who may send hundreds of Japanese citizens to the interior of a radioactively contaminated reactor, and so on. But thankfully, we don't live in such a world and freedom-loving individuals will fight hard if Matt Strassler's ideas about the way how the world should be politically organized become a genuine threat.

Second, Japan is not only one of the most technologically advanced countries in the world – for quite some time, it's been the ultimate #1 symbol of high-tech products. Foreigners who would be sent there would probably be unhelpful both because they don't know the local language, script, technical standards, and conventions but also because most of them are less high-tech.

Third, the international organizations – especially the U.N. – wouldn't even be capable of constructing a panel of "approximate counterparts" of the Japanese experts. We know quite something about the character of similar panels. For example, the U.N. created a climate change panel, the IPCC, 25 years ago where crackpots, unhinged ideology-driven activists, corrupt individuals displaying clashes of interest, mediocre railway engineers, and porn writers decide about all the important acts of the panel (one must belong to all five groups to become the chairman).

Less than one month ago, I also discussed a new U.N. panel of 26 science advisers. It's composed mostly of female de facto (and sometimes de iure) activists from countries like Barbados, Kenya, Ethiopia, Nigeria, Oman etc. Only 1 of these 26 folks, Shankar Sastry, has some links to engineering but his field is really autonomous software.

Do you think that this panel would be able to improve the reactions to the highly specialized technical challenges in Fukushima? Or do you think that the U.N. would be able of producing a much better panel of advisers although it has never done so in its 68-year-long history? One simply has to repeat: Matt Strassler's policy recommendations are stupid beyond belief.

Just to be sure. The most relevant existing international body is the International Atomic Energy Agency. Its delegations have visited Fukushima many times. Of course that they're friends. Of course that the international delegations didn't help and couldn't help much. They didn't get into the suits to do the hard work but this hard work was really what was needed and the most important decisions about the deployment of the workers always faced the key dilemma – safety of the population and the environment vs health and protection of bare life of the workers. IAEA hasn't "requested" to sacrifice 150 TEPCO kamikaze employees to further reduce all the (already small) risks and no international bureaucrats will ever do such things, hopefully, because that's incompatible with some decency that our world is still enjoying.

The following part of Strassler's text is dedicated to an incomprehensible sketch of some technical details of the challenges at Reactors 1,2,3; and 4. I think that the point is that the readers are supposed to think that Strassler is seeing rather deeply into the problems. But let me tell you something: you may extract these basic facts even from some better popular write-ups on the Fukushima challenges.

More importantly, none of these details are Matt Strassler's business. His (and others') specific recommendations for particular reactors would probably be incompetent, unwise, and counterproductive, but even if you imagine that they would be smart, there simply exists – and has to exist – a system that protects the behavior from random intrusions by random outsiders and Matt Strassler is a random outsider.

The Japanese engineers are doing their work which is difficult but it's just some work whose importance is local in character. It would be much more appropriate for Strassler to discuss the vapors coming from the floors of the Rutgers' NHETC, during a faculty meeting, for example – I have always found them a bit suspicious. ;-) In Fukushima, they are solving analogous problems but just because these problems are related to nuclear energy which the environmental ideologues love to demonize doesn't mean that it's appropriate for random outsiders like Strassler to intervene into TEPCO's and Japan's internal affairs.

So if I express myself very kindly and politely: Matt Strassler, please just f*ck off! Save your ill-informed fascist mis-ideas for your comrades in the Academia, please.

Some parts of the text indicate that Strassler does realize that the only way how the Fukushima affairs could influence the external world is the sale of fish some of which may turn out to be radioactive (I sort of doubt that the buyers aren't careful about these matters). But if he knows that the situation in Fukushima doesn't really create any international concerns, why is he proposing international watchdogs in charge of all the decisions and dedicated websites that try to investigate?

The situation in Fukushima isn't displaying the impact of a crime; it is a result of a natural catastrophe. A natural catastrophe that the affected country was wrestling with – and to a lesser extent, it is still wrestling. It's totally inappropriate, obnoxious, and I would say unethical for Strassler to act as some kind of an "investigator above them".

The last point: Some of the manifestations of Strassler's fanatical anti-corporate sentiments sound like jokes. I can't believe he's serious. If I haven't made it clear, one of the questions he asked in his blog post was whether someone knows of some credible sources about nuclear engineering that he has overlooked. (It's really a rhetorical question because whatever great resource you will give to him, he will tell you that the people behind it are industrial shills. This mudslinging is the real agenda behind Strassler's would-be impartial search for the objective information.)

Stanley Petrowski proposed Strassler found some people who are not engineers as well as the key engineer behind the website, Arnie Gundersen. But he didn't like him:
An engineering expert, but deep within the nuclear power industry. Potentially a very big conflict of interest.
LOL, surely you're joking, Prof Strassler. One is either understanding nuclear engineering issues or he isn't or something in between. But there is no "extra dimension" here. If you only tolerate folks who are real experts in nuclear power, you can't simultaneously complain that they have links to the nuclear power industry. Nuclear power is being studied and developed because it is useful; it is an applied science (combined with tons of engineering). No one studies technical details of reactors as a "pure science". It would be utterly silly and mostly physically impossible for someone to know all the technical aspects of nuclear engineering and have no contacts to the nuclear industry at the same moment. It's simply a contradiction. If you don't have sufficient contacts with those people, they wouldn't even allow you to learn many things.

Arnie Gunderson is clearly independent of TEPCO – which he pretty harshly criticizes – but for Strassler, he is still an industrial shill because he has worked in the nuclear industry at all.

Even if someone focuses on nuclear safety issues, he's likely to work for some nuclear-energy companies or have worked for nuclear-energy companies or at least be familiar with the nuclear-energy folks (the neutral nuclear watchdogs, like Dr/Ms Dana Drábová here in Czechia, surely know many of the nuclear-industry folks well and they probably aren't and she isn't in the state of war with them; of course that she could probably work for such a company as well if she were not a national nuclear watchdog – the expertise is closely related).

Strassler implicitly suggests that nuclear-engineering experts should be ambiguous about whether nuclear energy is a tolerable source of energy. But that's nonsense. Someone who believes in anti-nuclear conspiracy theories simply stands at such a low level of understanding or has such strong anti-nuclear sentiments that these circumstances prevent him from studying the technologies in depth. He can't be useful in the efforts to eliminate the consequences of the earthquake and tsunami in Fukushima. A real nuclear-engineering expert knows something not just about the "good stuff" that the nuclei are giving us but also about the risks and the possible undesirable events and processes. But he views these risks as "finite terms" in the equation. Someone who still thinks that they may be "insurmountable" simply hasn't begun to think as a nuclear engineer yet. If you want a competent nuclear engineer who simultaneously plays with the anti-nuclear memes known at Greenpeace, you won't find any because it's a contradiction. If any links of a nuclear energy expert to the nuclear industry are called "a clash of interest", then this clash of interest is a law of Nature and we must embrace it.

To summarize, I find Matt Strassler's pomposity absolutely indefensible. He may think of himself as about a genius flying above all the information sources about nuclear energy in the world and above all the experts in the nuclear industry but in reality, his ability to think about these issues is worse than the ability of an average educated man and his objectivity is worse than what one should expect from an average scientist. So Matt: Please don't act as a pompous fool.

And that's the memo.

Acid attack: near my home

A horrible event occurred after 8 am today in the street that starts 100 meters from our apartment building – but the place is about 900 meters from us. An attacker with a black jacket and a black hood or cap jumped from a bush and poured some acid on the face of Ms Martina Pů***á (I know the full identity now, update Wednesday), a 25-year-old worker in Škoda Transportation who was said to be beautiful and some Internet researchers claim that she was single, recently broke with her boyfriend, and works as a head hunter for a related agency employing foreigners (perhaps even those from Muslim countries where acid attacks are more common).

Some pedestrians around saved her life with liters of water – at least so far because her condition is still critical. She was probably a Czech citizen, incorrectly said to be originally a Slovak from Čadca in much of the media (Northwestern Slovakia, near the Czech and Polish borders, as understood from her Slovak plate number CA-135BX that isn't being hidden in the videos on TV etc.; however, her name with an "ů" makes it clear that she's Czech and the car was just borrowed from a Slovak firm – corrections to this paragraph were made on Thursday).

I was going to scene around the noon, with a black jacket and a black cap on (it was before I knew the basic data about the likely attacker – I wouldn't try to provoke with the colors otherwise, especially because some other physical descriptions might agree with mine, too), so you may imagine that others were looking at me at least as intensely as I was looking at them (except for the cops who probably know much more to recognize the culprit).

This sort of an attack is scary, the culprit deserves quite a punishment if he is found, the motivation of a refused boyfriend is the single most likely possible motive (and a not-hired potential employee from the Muslim world is probably the second in the list), and I feel sort of paranoic because there may be many types of "unusual" attacks like that.

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reader lucretius said...

This is an excellent blog entry Lubos I am happy to say I agree with every word (well, if there is a word I don't agree with I have already forgotten it ;-))
I have just returned from Ukraine, from a showing of a film about my uncle in the town in which he was born, out of whose Jewish population he was one of very few survivors. He later became a military nuclear engineer in Poland, and after emigrating to Switzerland he worked for the Swiss government in the agency responsible for the safety of all swiss nuclear power plants. He had a number of discoveries and patents in this field and was the author of a method of measurement of radiation leaks which was supposedly 10,000 times more accurate than the previous one (that what his Swiss colleagues claimed in the film). It was remarkable that he, an immigrant and a former senior military officer (he was a professor at Poland's military technical academy, with the rank of a colonel) was hired for this kind of extremely sensitive work by the Swiss. In fact, I remember that once he came to England (where my parents and myself were living) to attend a conference at the Nuclear Energy Nuclear Establishment at Harwell, the British would not let him do so since they considered him a "security risk" (under British standards) until the Swiss government threatened to withdraw altogether. The Swiss guy who made the film told me that he had asked the man who originally hired my uncle why he did so - and was told that the real reason was that every qualified Swiss candidate for the job was form ETH and he was suspicious of cliques of academics from the same institution, so he thought that this East European would provide an "independent view of things". Well, this seems to me sort of opposite of Matt's view of "independence".

Although I was not much interested in technology (which is why I don't remember much about these matters) I remember that my uncle was thoroughly convinced that nuclear energy was the one of the safest forms of energy available and Europe in particular had no other alternative (that was of course a long time before fracking or even AGW scares). He also visited Japan when I was already living there at the invitation of the Japanese and found their safety procedures excellent (although not being Japanese he might not have been aware of the effects of a tsunami).
Actually, the mistakes made at Fukushima had little to do with any nuclear engineering expertise. In fact, the entire tragedy can be attributed to the fact that the potential power of a tsunami had been underestimated and the reactors were not placed at a higher elevation. Everyone in the area affected by the tsunami who succeeded in reaching the third floor of practically any building was safe. The earthquake itself caused no problem to the power stations - both reactors achieved cold shutdowns as expected.
Having a team of international scientists without knowledge about earthquakes and tsunami would have been as useless as this Strasser's blog entry.
There is a problem in that Tepco ignored the advice of Japanese experts that it consulted in connection with this, but the reasons are more to do with certain aspects of Japanese culture that anything that Strasser insinuates.

reader Luboš Motl said...

Thanks for your synergy, Lucretius, and your uncle seems very interesting. He would get bad grade from independence by Matt Strassler, I guess.

A reader of Matt's blog has criticized Wade Allison, a particle physicist and a nuclear advocate, as "highly polemical" etc. Well, I just looked at

and it's totally sensible - focusing on things like the absurdly low radiation limits some folks want to require (much smaller than the natural background). Strong words about these issues are fully appropriate - and compatible with impartiality - because some of the people's requirements on these issues have become insane.

This Allison is totally sensible and well-informed about nuclear energy in general but he's still e.g. a climate alarmist as clear from summaries of his book

Well, I am used to it. But if all people with any experience in the nuclear industry are labeled shills and they even add particle physicists without experience who just reasonably emphasize how crazy certain requirements and worries seem to them after they have learned the numbers, well, then only Greenpeace is impartial enough (OK, or the Academic cliques living in the full group think you mention - they must also have a totally boring, uninspiring intonation to qualify). ;-)

reader Nathan Cook said...

A large number of people were subjected to a small extra quantity of radiation. If the Linear No Threshold model of radiation induced cancer is correct, then the Fukushima incident will unfortunately kill a number of people. You are by no means obligated to accept LNT, there being insufficient evidence either way - it is out of an abundance of caution that this model is assumed to be true. What would be fundamentally irrational would be to switch to coal power out of fear of this sort of event. The number of deaths attributable to coal particulate emissions in one year is orders of magnitude more than anything Fukushima could manage. Even the Chernobyl disaster will at most only cause as much illness as a few years of coal power. Sadly Japan is already boosting coal usage and planning new coal power stations.

reader Alexander Ač said...


I am not strongly against nuclear power, since it is the only baseload, concentrated and low-carbon energy source, but here is the fact:

"World nuclear power generation declined by 6.9%, the largest decline on record for a second consecutive year" (BP, 2013):

so I am not entirely sure about the "victory" claim at the beginning.



reader Luboš Motl said...

I meant that the events showed that nuclear energy is a great technology; nuclear energy was the winner according to the evidence.

The fact (mentioned by you) that the usage of nuclear energy has decreased therefore doesn't show a loss for nuclear energy. It's a loss of the people and the nations who responded in this irrational way.

reader Dilaton said...

Seems Matt Strassler tolerates the wisdom and comments of only one single expert in nuclear physics / engineering / safety etc :

Matt Strassler ... :-D

First demanding that only experts who know the business should comment, then calling them out for their comments not being appropriate for laymen, accusing them of being not objective or biased or even dishonest (?) when explaining facts, etc really looks like he wants to abuse people who are in the know about these topics for his own purpose, whatever this is in this case ...

I did not expect this from Matt Strassler, but know this style of comment moderation from the Trollking rather...

reader Uncle Al said...

Store 1 GWh of energy as electrolyzed water. This is the one hour output of a single San Onofre nuclear reactor.

(1 J/W-s)(3600 sec/hr)(10^9 W-hr)(1 kJ/1000 J) = 3.6 billion kJ
(3.6×10^9 kJ)/(285.82 kJ/mole) = 12.6 million moles of water
(1.26×10^7 moles)(24.465 L/mol at 25 °C) /(1000 L/m^3)= 308,000 m^3 hydrogen, H_2 (and half that volume of oxygen, O_2)
(308,000 m^3)/(5380 m^3/Goodyear blimp) = 57 Goodyear blimps, plus half-again more for the oxygen, then to recombine in a fuel cell farm.

U-235 fission averages 200 MeV. 1 GWh = 2.25 × 10^31 eV, or 2.3 cm^3 of U-235 fissioned.

reader Mikael said...

Dear Lubos,
I agree that the real consequences of the Fukushima nuclear incident are remarkably unsevere in relation to the attention it got. But what about the very real threat that the greater Tokio area might have become inhabitable? Shouldn't we factor it in into our analysis?

reader Dilaton said...

I just scrolled through the comment section over there, it is very very strange and gives me an uneasy feeling, as if I've stumbled into the meeting of a strange sect ...

Matt Strassler's intention seems to be to make people say exactly the things he wants to hear in exactly the specific tone he appreciates. But he is not really looking for assessments of independent experts who know what they are talking about and why, he seems to have the conclusions he wants this pseudo discussion to result in already in his mind ...

So why did Matt Strassler not simply make his post a bit longer to write down the unique outcome of the "discussion" he will tolerate or allow, and disable the comments afterwards ...?

As an expert in the topics of the post over there I would not feel compelled to comment there at all ...

reader Eugene S said...

You are by no means obligated to accept LNT, there being insufficient evidence either way

I'm not sure that's true any longer. According to this article that appeared in the NYT last month,

research on the [Hiroshima and Nagasaki] bomb survivors has found that at lower doses, below 100 millisieverts, radiation causes no detectable elevations in normal rates of illness and disease.

reader Luboš Motl said...

Dear Mikael, we should factor it in but the change of the analysis will be undetectable. Why do you think that the threat is "very real"? They're places 240 km away.

Note that the Chernobyl Exclusion Zone was only 30 km around the power plant. It is not easy to make 200 km uninhabitable, not even with the most messy reactors (and most careless treatment) they had in Chernobyl.

reader Luboš Motl said...

That's a very interesting report on research, Eugene!

I wondered about the violations of the linearity with aspartame, a major artificial sweetener, when I was reading some conspiracy theories at a website that is otherwise ideologically somewhat close to me.

Aspartame is producing methanol and formaldehyde in some reactions etc. and the story is that it poisons you. In reality, those things pretty much can't get into the blood stream and the organism is ready to deal with a certain amount of these things, anyway. So perhaps it's the same with the effects of radiation.

reader TomVonk said...

Foreigners who would be sent there would probably be unhelpful both because they don't know the local language, script, technical standards, and conventions ...
With this comment my respect for our humble correspondant just increased by an order of magnitude.
I have been working on large international projects (yes, nuclear too) for more than 20 years and this insight is for me simply staggering because people like Lubos who had no experience with large international projects should be unable to see this fundamental issue.
Indeed, let's take f.ex a project similar in complexity to Fukushima like Stokman.
Stokman is an off shore gaz project in the Barents sea.
The purpose is to produce a huge gaz reserve underwater and in Arctic conditions (storms, icebergs, winter nights, rogue waves etc) - about 3500 billions m^3 what is about 350 years of Czech gaz consumption.
So now an average academic (like Strassler) would imagine that the biggest issues for such a complex project in a chaotic and hostile environment would be scientific, e.g accessible and understandable to the selfsame average academic.
Nothing could be farther from truth.
While there are indeed some technological and engineering challenges, those are not so difficult and are generally well understood and mastered.
The largest and most difficult challenges are in fact standards, regulations and ... language (which is russian in this case).
For example an average academic doesn't even imagine that regulations in Russia prescribe the work duration outdoors as a function of temperature.
And as in such a project the goal is NOT just to write a dozen of pages of equations but to construct a real functionning plant within a given schedule and a given investment budget, this constraint is paramount for the project team.
The technical standards prescribe diameters of pipelines and distances between equipments.
The safety standards prescribe operating pressures, temperatures and equipment parameters.
Besides there are russian standards and international standards where the former are in russian while the latter generally in english.
Both are not always consistent and concrete engineering solutions have to constantly satisfy this large set of constraints.
Well Lubos with this example I wanted only to illustrate your sharp insight (how you could see that without experience is a mystery for me) that large and complex facilities like Fukushima or Stokman are completely and utterly far beyond anything that a Strassler could imagine or understand.
The amount of the necessary expertise in these fields (stndards, regulations, legal and contractual constraints, language barriers etc) is huge and only companies can afford and train people to have them in sufficient quantity and quality.
People like Strassler or any other average academician for that matter would never be hired in such an industrial project because they not only are totally ignorant of the most important issues but they would be a constant danger for the success and safety of the project.
Fukushima designed by Strasslers would go LOCA (Loss of Coolant Accident) already at start up if it ever started and no tsunami would be necessary.
Of course the same would be true for any external "expert" commission unless the commission hired exclusively highly paid true nuclear engineers who work for nuclear companies already anyway.

reader Gene Day said...

Tsar Bomba was likely the cleanest nuclear blast in history. The Soviets could easily have produced a yield of 100+ megatons with a uranium tamper but it would have been very dirty.

reader Michael Brown said...

LNT was adopted as a conservative standard long before long term low dose risks were understood (indeed there is still a lot that is not understood in radiobiology). I am not a radiobiologist or medical physicist myself, but I am married to a radiation therapist and through discussions with her, her colleagues and a number of medical physicists I can attest that LNT is absolutely false and this is well known in the medical community (or at least if this is wrong and LNT is right it would be big news to these people who are using radiation to treat cancer on a daily basis with apparent success). But as far as I know the old safety limits haven't responded to this and represent an (arguably) over-conservative level of caution. I don't know of a journal reference to support this off hand, but there is a good book by Wade Allison, a physics prof. at Oxford, which seems to be well researched and pitched at a popular audience: