> According to federal reports, the contractor ingested some of the reactor water before being yanked out, scrubbed down, and checked for radiation. They walked away with only minor injuries and about 300 counts per minute of radiation detected in their hair.
> That sounds like a lot, but apparently it isn't terribly serious. He underwent a decontamination scrubdown and was back on the job by Wednesday.
300CPM above background is considered very low - likely why they classified this as non-emergency - the only reason it was reported was per NRC cfr that states any time there is transportation of a radioactively contained person offsite, it must be notified.
For reference, in Canada, that is considered trace contamination and not dose. You would experience 300-800 CPM on a commercial airliner during the entirety of your flight, for comparison.
edit: adding to this that the site in question, Palisades, is shut-down and is under decommissioning and was not operating at the time - so while the water would have had some radioactivity due to exposure to the formerly active core, it was not like falling into an operating reactor or into moderating heavy water... also something that cannot happen with a pressurized reactor such as this one.
I thought 50-130 CPM above background was considered trace exposure. But yeah I didn't realize it was a decommissioned core... idk there are so many red flags in this story.
EDIT: 300-600 CPM above background radiation levels is for EXTERNAL environmental monitoring, not for POST-DECONTAMINATION readings on a contaminated person.
I'm sure your father is a very accomplished gentleman. But I was asking why your armchair analysis is better than the experts who actually know what happened here?
I maintain the complete archive of every publication my father did from 1969 to 2019 and continue to update the archive based on new publications. I use the data to train Nuclear Radiochemistry AI Agents and while I do not have my father's credentials, I actively use this dataset to learn about his field, and from my limited knowledge here I felt the need to comment. After all, what is skepticism if we can't share and teach each other what we know, right?
> I use the data to train Nuclear Radiochemistry AI Agents and [...]
As someone who is not involved in this ongoing discussion, I have to just say that invoking LLM agents when asked for credentials is not going to go in your favor.
My use case for data that exists that is pre-AI scientifically vetted work is completely divorced from the specifics of this conversation actually. If I want to do paper-maché sculptures with printouts of these papers, and I still commented on this post, would that be better or worse for you, here?
I was just sharing background. I want to make good models that can help scientists do work. Your personal feelings about LLMs and their capabilities feels quite distinct from the focus on this post, and the chain of comments that have led us here.
So you don't have the necessary credentials, and you still wouldn't be qualified to comment even if you did have them unless you had access to the internal data. But no worries, I'm sure you'd be OK getting surgery from a surgeon's son who never went to medical school nor read your chart.
I would take the advice of a surgeons son, who is also somewhat active in the field, that something sounds fishy about a operation, to further look into it. That is very different from letting him perform the surgery.
There is incentive to play down accidents. No idea what happened here, I actually rather think it recived publicity because falling into a nuclear reactor pool sounds way more dramatic than it is, but ... not my area. Still was happy to get arthurcolle's input.
There is also incentive for people to inflate their sense of importance by weighing in on topics they're not qualified on, especially if it's motivated by a sense of familial pride. You can see elsewhere on this thread that arthurcolle self-admits a lack of familiarity with basic interpretation of CPM.
Misinformation, whether ill-intentioned or not, does real and tangible harm to our society. Misinformation about the supposed dangers of nuclear power, as arthurcolle is spreading, are especially harmful because they form the foundation are the biggest obstacle to safe, clean, cheap, and abundant energy that could radically improve our lives at the systemic level.
"Misinformation about the supposed dangers of nuclear power, as arthurcolle is spreading "
I maybe did not read all of it, but which missinformation is he spreading exactly?
(Follow up, why are you in a position to judge that? )
As for missinformation in general, I happened to be born after chernobyl. Where the authorities in eastern germany said, all is fine. But since the people got western television, where they said no, not fine, children may not go outside while the radioactive raincloud is still there, my immediate experience is rather people downplaying the dangers.
> Every Day 10,000 People Die Due To Air Pollution From Fossil Fuels
> The NBER study found that “the switch from nuclear power to fossil fuel-fired production resulted in substantial increases in global and local air pollution emissions.” A key reason for the increased air pollution was that “lost nuclear production was replaced by electricity production from coal- and gas-fired sources in Germany as well as electricity imports from surrounding countries.”
> The study concluded that “the phase-out resulted in more than 1,100 additional deaths per year” due to excess mortality from the consequences of increased air pollution. Since 2011 that totals more than 10,000 deaths, far more than all deaths attributable to nuclear power in history.
Are you arguing about nuclear safety compared to fossil fuels with me? I was aware of those numbers, thank you.
But I asked for cases where arthurcolle was spreading missinformation, which is what you claimed and which is what I perceived as an unecessary attack.
Perhaps you should finish reading the threads to discover his numerous self-admissions of limited knowledge and incorrect statements when confronted with people who cite sources
Thanks for giving me the chance to clarify. You're right, of course. I was using it in the spirit of the phrase "violent disagreement" which is meant figuratively.
Off topic, but the idea that the “violence” of ideas, where the only thing in play is your point of view, is somehow equatable to physical violence, where physical integrity is at risk, is one of the least endearing features of the 21st century so far.
I cannot overstate how dangerous to human prosperity this false equivalence is. It is a first-tier ideological scourge that we entertain at great peril both to critical thought and the notion of objective truth itself.
On the other hand, it’s an excellent proxy to clarify that an idea, position, or sometimes even an entire ideology or its sycophant exist for entertainment purposes only and must not, on their own merits, be taken seriously.
Are we really so isolated from the brutality of nature to think that the inconvenient beating of a butterfly’s wings is the same category of experience as being disemboweled and eaten alive by a hungry beast?
Or is it that the whole ideological sham of the violence of ideas is merely a cowardice, a poverty of ingenuity, a plea for clemency by virtue of infantilism?
The pen, or the thought given flight, is mightier than the sword.
That does not make an idea a sword. It is in character , spirit, reach, and endurance a very different type of thing. A sword can be forged from an idea, but an idea will never spring forth from a blade.
Hell in a hand basket, get off my lawn, and uphill both ways to school. Lol.
Yep you know better than the people who have the credentials you don't and the access to internal data you don't. I don't see what's holding you back from doing surgery, qualifications and context are no barrier to the application of your self-imagined expertise.
I don't claim to know better. But restarting a $1.5B plant after 2 years of inactivity and having a worker fall into a vat of radioactive water and still being at 300 CPM after a decontamination procedure is not normal.
Phrases such as massive red flag and bureaucratic nonsense were claims you knew better.
Who claimed the event was normal? A worker falling in non contaminated water would not be normal. Many things are bot normal and not emergencies. False dichotomy and straw man are logical fallacies.
Were the plant cost and status meant to support your claim 300 counts per minute was a red flag? They appeared irrelevant.
If I'm not, then we're not grounded in the same consensus-driven objective reality, making this conversation meaningless, and therefore not worth your time to reply further.
I care enough that I would trust assessment of their health and condition only to qualified professionals with access to the relevant information, just like anyone else that I care about
I'm sorry you feel that way, but I actually feel like I shared fairly demure commentary and then presented my background with full transparency. I care mostly about the health of this worker, and less about the opinions of a 1 minute old account.
My account is a couple years old, and I’ll agree with what fekxpurrrt said — you expressed doubt without evidence, people challenged your doubt, and you’ve never really satisfied their objections. The experts do know more than you. A brief Wikipedia investigation corroborates what the experts have said. They seem trustworthy, it’s unclear why your doubt should be taken seriously.
Everyone is wrong sometimes. When you realize you’re wrong, do you update your beliefs to be correct, or do you double down?
> The non-emergency classification is bureaucratic nonsense
FTA: “This is an eight-hour notification, non-emergency, for the transportation of a contaminated person offsite“
I read that as that the “non-emergency” classification isn’t for the victim or the “fell into a nuclear reactor pool”, but for the effects on those outside the facility of sending the victim off site.
A CPM value means nothing without additional context. Counts vary based on detector type and size, radiation type, energy, distance and geometry, all sorts of things. They're not comparable except in identical contexts.
This is why the Sievert exists as a unit.
As a general rule, falling into a reactor pool is probably fine, as long as you don't reach the bottom. (But please don't try it.)
> On August 31st, 2010, a diver was servicing the spent fuel pool at the Leibstadt nuclear reactor in Switzerland. He spotted an unidentified length of tubing on the bottom of the pool and radioed his supervisor to ask what to do. He was told to put it in his tool basket, which he did. Due to bubble noise in the pool, he didn’t hear his radiation alarm.
When the tool basket was lifted from the water, the room’s radiation alarms went off. The basket was dropped back in the water and the diver left the pool. The diver’s dosimeter badges showed that he’d received a higher-than-normal whole-body dose, and the dose in his right hand was extremely high.
The object turned out to be protective tubing from a radiation monitor in the reactor core, made highly radioactive by neutron flux. It had been accidentally sheared off while a capsule was being closed in 2006. It sank to a remote corner of the pool floor, where it sat unnoticed for four years.
The tubing was so radioactive that if he’d tucked it into a tool belt or shoulder bag, where it sat close to his body, he could’ve been killed. As it was, the water protected him, and only his hand—a body part more resistant to radiation than the delicate internal organs—received a heavy dose
One of my favourite bits (and a fine example of Randall's sublime humour), comes right at the end:
But just to be sure, I got in touch with a friend of mine who works at a research reactor, and asked him what he thought would happen to you if you tried to swim in their radiation containment pool.
“In our reactor?” He thought about it for a moment. “You’d die pretty quickly, before reaching the water, from gunshot wounds.”
> A CPM value means nothing without additional context
Here to confirm this. If you're googling "CPM" you'll find charts that say different things. That's why you need to read carefully. Better, just chill, it is okay that you don't know. It's nuclear physics. It's not a subject you're expected to know about.
For CPM, what matters is "CPM of <WHAT>"
CPM just tells you the number of particle detection. It does not tell you the particle type (e.g. alpha, beta, gamma) nor the energy level (i.e. eV). Without context, it is meaningless.
As an example, I can confidently say you are getting over 100bn CPM right now. The reason it doesn't matter is that this is neutrinos and they're not interacting with you[0]. 1CPM or 1e20CPM, who cares. Conversely, 1 CPM can be deadly. You definitely don't want to be hit by a single ReV (10^27) proton (good luck producing that though). Context matters.
> This is why the Sievert exists as a unit.
Which still needs context.
Sievert is joule per kilogram. So energy divided per mass, much like pressure is force over area. But determining biological impact still takes interpretation. You have weight factors by particle types (e.g. alpha = 2x beta) and there is also weighting factor for internal/external dose and locations like soft tissue (e.g. higher weighting for dose at throat vs dose at hands).
This is why it is incredibly important to use caution when interpreting radiation values. If you don't have training in this it is incredibly easy to unknowingly make major errors. The little details can dramatically change the outcome. Context is critical.
I'm not here to tell you how to actually do the calculation (you'll need a lot more info), I'm here to tell you that it's not easy and you're likely doing it wrong. The experts are not dumb. You're just missing context and a first order approximation is nowhere near enough for an accurate conclusion. It's nuclear physics lol
It shouldn't need be said, but nuclear physics is, in fact, complicated.
> [Y]ou are getting over 100bn CPM right now. The reason it doesn't matter is that this is neutrinos and they're not interacting with you.
I mean, if you actually had a neutrino detector that produced 10e10 CPM over your cross-section, then it would matter for you, because particle physicists would kidnap you to learn the secret :)
Honestly, the military would probably come after you first. Or maybe an oil company? Frankly because if you could detect neutrinos at that resolution you would be able to produce a really good mapping of... just about anything. From the inside of the Earth to the inside of a secret military facility on the opposite side of the planet. Not to mention you've also invented a communication device that is essentially unjammable[0].
Sufficient to say that you'd be very popular, but in probably the least fun way possible.
Thank you for the followup (familiar with the XKCD)
Dumb question from a true non-expert:
So CPM varies with all those factors you mention, but wouldn't the site HP team know exactly what detector they used, the geometry, distance, etc.? They could convert to dose if they wanted, right?
Why report the ambiguous "300 CPM" instead of an actual dose estimate in mSv/μSv? Seems like that would be more useful for any medical team, any set of potential regulators or regulatory bodies as well as just general public understanding (drawing on my father's work here as he always emphasized the tension between "public fears radiation unnecessarily" and "industry safety protocols are inconsistent")
Follow-up: Is there any legitimate reason to report CPM instead of dose after a contamination event? Or does staying with CPM keep things conveniently vague?
Because from my limited understanding, if they did a proper survey, they have everything needed to calculate dose.
> Why report the ambiguous "300 CPM" instead of an actual dose estimate in mSv/μSv?
It is a technical document. It is meant to communicate between experts, not to the public.
> Is there any legitimate reason to report CPM instead of dose after a contamination event?
It's not nefarious, it is the measurement that they had. CPM is an easier measurement to get. And keep in mind that these notices are just a small part of the communication going on. They're meant to be brief.
To get the actual effective dosage you'll need a lot more information and calculations. The CPM can give you a decent estimate, if you already know context, but it is meaningless if you don't. So to an expert in that space it's a good quick estimate, but to an average person it isn't (even to above average people).
In context is also being used as a stepping stone for quick evaluation. They sent the guy to the hospital and he'll get a better estimate of dosage there. I'm sure they also were doing those calculations prior to sending him out. It may just be customary to use CPM units. That part I don't know. Here's the page they reference though[0] (there's only a single (xii) so easy to find).
[disclosure] I have training in nuclear physics, including in radiation dosages (I worked on developing shielding materials), but I have not worked on a reactor (though I've seen reactors and Cherenkov Radiation :) so the customs of the bureaucracy are beyond my wheelhouse. But from my experience I'm not surprised by this. I would expect a lot more documentation and accurate measurements are being passed through other channels.
Looking at these bulletins, they appear to be quick summaries of pretty much any nuclear related incident that happens in the US, no matter how minor. I would assume that these are mostly intended for public transparency, and as for a quick reference point for regulatory action. Introductory slide on a PowerPoint sort of material.
In that context, I'd guess that the 300 CPM figure is just a signpost that says "we measured the worker to make sure that he was safe to release to a hospital."
Is the information intended to be given out to the public in a manner in which the general public can interpret? No. It's encoded lol. But you can hear that on the radio and if you're trained (could go to a public library to train yourself) and yeah it makes sense. It is specifically intended to be concise and communicate only the absolute minimum amount of necessary information.
For another example, look at arXiv. Is it public? Yes. Are the papers published there written for the general public? No. They are written for peers.
So yes, it is "public transparency", but not for transparency to people who aren't train in nuclear physics. (Which is what I previously said)
>Is there any legitimate reason to report CPM instead of dose after a contamination event?
Basically, the procedures for certain environments differ. If you want to gather dosage data, you use a dosimeter. If you want a binary Yes/No method of detecting contamination, you use a geiger counter and determine if the count rate is above a certain range (depending on background radiation and other factors).
The 300CPM metric just indicates whether they're clean or not after they've been scrubbed down. It doesn't measure the dose they took.
I would imagine the on-site team would know, yes. I don't know why the report only gives a measurement in CPM, but just because the person was sent off-site doesn't mean the levels were dangerous. Thresholds at nuclear facilities tend to be very low for safety.
The USNRC is currently not operating normally due to the government shutdown. Perhaps that has something to do with it.
CPM is a measure of rate, GBq is a total amount. And 300 CPM is basically nothing. People live their entire lives in places where the natural background radiation is higher than that with no increased chance of cancer.
300 CPM on its own is both meaningless and not high.
CPM is a raw stat from the sensor. There’s many different designs of dosimeters and they all read differently so you have to ask “what brand and model did you use?” You then apply a function to the data to normalize it into a real unit.
But CPM is the cool thing that makes the click-click-click sound. (The absolute rate of clicks also is not useful.)
Unless I'm misinterpreting what you mean, I believe if it was reflected in the hair in the immediate aftermath, it wouldn't reflect internal circulation because hair does not grow that fast. It would have been from exposure to the pool rather than any amount ingested.
External contamination is not comparable to internal, at all. Bq is a terrible unit to understand radioactive danger. Doses are usually detected in Grey, then converted into Sievert because Grey didn't take into account the difference between Alpha radiation and the others. And even then, when someone is truly contaminated, we calculate effective dose per organ.
The poor guy who fell in the pool probably didn't take any Alpha ray, wasn't taking all the radiation on a specific place, and while in my country we would calculate the dose he took before sending him back to work, he would probably work again in the same nuclear sector (this isn't the case for anyone, I know someone who dive to get the radioactive/explosive/poisonous trash we put in the water in the 50s until the 90s, he now cannot work on any radioactive trash.)
The non-emergency classification is bureaucratic nonsense. This is an internal contamination event with unknown but potentially severe consequences.