A worker fell into a nuclear reactor pool
nrc.gov
nrc.gov
Worker was wearing a life vest.[2]
[1] https://en.wikipedia.org/wiki/Palisades_Nuclear_Generating_S...
[2] https://www.mlive.com/news/2025/10/michigan-nuclear-plant-wo...
it sounds like "guy felt down in a volcano, but fortunately, he had a life vest"
Yes, radioactivity isn't good. You should not, for example, drink this water, or swim in it once a week for good luck. But, it isn't magic death fluid, the worker will have been decontaminated - destroying clothing, washing skin and so on, and the additional exposure means they might get more monitoring, but they're probably fine.
Maybe there is a problem elsewhere, maybe the pool is contaminated, maybe the sensor used is very sensitive and 300 cpm is not as concerning as it would seem.
It sure would be nice to have actual data, wouldn’t it?
Regulatory bodies have adopted the LNT (linear no threshold) model and for good reasons. Every exposure increases your likelihood to get cancer eventually. Many things do, such is life, and radiation is one of them.
And it should show up in realtime monitoring of the water, unless they just turned that off.
> The individual was decontaminated by radiation protection personnel but had 300 counts per minute detected in their hair.
This event will result in acute hair loss. From shaving machine.
> 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.”
At any rate 300 is widely recognizable as not an alarming value for a typical contamination detector in a typical configuration, but the report is likely slightly deficient because it does not specify how the measurement was taken. However, even if we accept 100 as the background CPM value, 300 on 100 does not represent significant contamination in a typical environment (but does imply some occurred).
Of course it varies for "civilian" devices from EBay.
They put that count into NRC report. It means that it has pretty specific calibrated meaning for that regulated environment.
>However, even if we accept 100 as the background CPM value, 300 on 100 does not represent significant contamination in a typical environment (but does imply some occurred).
report mentions 300 clearly as something above normal, whatever normal is there. And that is after decontamination. Clearly the source of contamination - the pool - is much higher than 300.
Anyway feel free to explain why supposedly not calibrated value was put into an official NRC report instead of some calibrated value.
It is counts per minute in an undefined, arbitrary sensor. Which could have a alpha radiation transparent sensor (and hence show alpha particles), or be from a low sensitivity geiger counter which can only detect high energy gamma radiation (for say fallout/emergency use). https://en.wikipedia.org/wiki/Geiger_counter
It could have a small sensor, and hence require high flux for a given CPM, or a physically large one - and catch more disintegrations per minute/CPM for the exact same actual amount of radiation.
As to why it is in a government document is why we’re all wondering what is going on. It certainly isn’t the only WTF thing the government is doing right now, is it?
Mind linking to something concrete?
What I did find was numerous documents noting that Geiger counters needed to be calibrated to generate useful dose rates because CPM by itself is useless without a bunch of other work to characterize the sensor and radiation type.
I mean I would rather lick a keyboard than a butthole (with exceptions of course)
There are numerous anecdotes from the USS Reagan that contradict that prosaic interpretation (of the reason it was abruptly moved),
https://www.thenation.com/article/archive/seven-years-on-sai... ("7 Years on, Sailors Exposed to Fukushima Radiation Seek Their Day in Court" (2018))
E.g.,
"He was issued iodine tablets—which are used to block radioactive iodine, a common byproduct of uranium fission, from being absorbed by the thyroid gland—and fitted for an NBC (nuclear, biological, chemical) suit. He was also told not to drink water from the ship’s desalination system. [...] Torres, the senior petty officer, recounted, “One of the scariest things I’ve heard in my career was when the commanding officer came over the loudspeaker, and she said, ‘We’ve detected high levels of radiation in the drinking water; I’m securing all the water.’” That included making showers off limits."
Do you mean because it's distilled? Distilled water is perfectly safe to drink.
And "resalinated" is nonsense. Water isn't safe because it contains salts.
Apparently they do have concerns.
Well yeah. If someone falls in water at work, you get them checked out at the hospital. The paltry amount of radiation is kind of the least of your worries if there's even the smallest risk you got some water in your lungs.
People can drown on dry land from about a tablespoon of water getting into their lungs.
Well, I don't think there's such a big risk of that. Falling into a pool is something most of us have probably done. Being pushed by a friend as a kid for example. The risk of drowning is probably pretty comparable to the risk from the radiation (negligible).
> In the past, these terms were used to try to explain that some fatal drowning victims had very little water in their lungs at autopsy. Now it is understood that little water enters the lungs during drowning. Moreover, when water enters the lungs, it is rapidly absorbed when breathing starts again. The amount of water that enters the lung does not determine the amount of injury or determine the treatment of drowning. The amount of injury from drowning is due to how long the victim is without oxygen.
Source: Red Cross
Even a tiny amount of water in your lungs is a trip to the hospital.
The amount of radiation that guy was exposed to is roughly the same as eating a banana, or driving through the middle of Aberdeen with your car windows down inhaling all the radon off the granite.
You’re probably thinking of something along the lines of pneumonia, which is different than breathing some water and coughing it back up.
For the record, I think the GP comment is way off-base saying drowning is uncommon.
If there's a bit of water in your lungs, a surprisingly small amount, it causes massive inflammation and your lungs start to fill with fluid. It's called "secondary drowning", and it happens a couple of hours after.
My water rescue course is up to date. When's yours due for renewal?
If you aspirate a surprisingly small amount of water, especially if it's not very clean, then you are risk over the next few hours, not days.
Maybe don't set too much store by AI-generated nonsense.
Allow me to quote an article from Cleveland Clinic Journal of Medicine https://www.ccjm.org/content/85/7/529 (AI generated nonsense of course)
> Secondary drowning, sometimes called delayed drowning, is another term that is not medically accepted. The historical use of this term reflects the reality that some patients may worsen due to pulmonary edema after aspirating small amounts of water.
> Drowning starts with aspiration, and few or only mild symptoms may be present as soon as the person is removed from the water. Either the small amount of water in the lungs is absorbed and causes no complications or, rarely, the patient’s condition becomes progressively worse over the next few hours as the alveoli become inflamed and the alveolar-capillary membrane is disrupted. But people do not unexpectedly die of drowning days or weeks later with no preceding symptoms. The lungs and heart do not “fill up with water,” and water does not need to be pumped out of the lungs.
> There has never been a case published in the medical literature of a patient who underwent clinical evaluation, was initially without symptoms, and later deteriorated and died more than 8 hours after the incident. People who have drowned and have minimal symptoms get better (usually) or worse (rarely) within 4 to 8 hours. In a study of more than 41,000 lifeguard rescues, only 0.5% of symptomatic patients died.
Maybe don't set too much store by what some random "water rescue course" instructor tells you, especially if it sounds like complete bovine excrement.
Anytime someone claims knowledge based on common sense, it's a red flag. Or, as we used to say, "Common sense tells us they're a witch! Burn them!".
More like "send 'em to the ER, my ass is covered".
See https://what-if.xkcd.com/29/
“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.”
The site contains the most dangerous poison on Earth, that is also a key component in the most feared weapon on Earth. Do you suppose in the UK they just put up signs saying "Sir or madam, kindly do not steal our plutonium"?
I hope I'm misremembering that but it's a pretty strong memory that totally locked in for me that that water is not necessarily dangerous.
I bet there's some good chance of getting wacky extremophiles though!
edit: sorry for being lazy, I scrolled a bit more and found it.
Hot spring baths usually top out around 42-43C
But now 100% sure that actually happened. Also it was likely a professor and not a working engineer drinking the water which makes much more sense.
While I do see this as a form of hazing which I am morally opposed to-
8oz (.237 liters) of primary coolant in a properly maintained pressurized water reactor might contain up to 13mrem of orally ingestible radiation, or approximately the radiation of a chest x-ray. (For comparison you get between 3-8 milirem on a 7 hour transatlantic flight)
Don’t make it your primary source of hydration and you’ll be ok. If the fuel is degraded or there is a leak (unlikely in properly maintained PWRs) the radiation dose is significantly higher.
I'd drink it. It's just extremely pure water, with a nuclear flashlight at the bottom of the pool - which no one could see, even if they had gamma-ray glasses on[1], because the water attenuates it so much.
[0] Or ions of hydrogen or helium, in the case of alpha and beta radiation.
[1] Which it turns out were way less cool than the Sea Monkeys(tm).
The primary coolant is not simply pure water; it contains boric acid, lithium hydroxide, dissolved hydrogen, and trace corrosion products like iron, nickel, cobalt, and chromium. Under power level neutron flux, some of these elements become short- or medium-lived radionuclides. Once removed from the core, most of the activity decays within minutes, but during operation the water is measurably radioactive.
An eight-ounce sample taken from the loop at power would carry roughly the dose of a chest X-ray before it decayed away, due to these activated isotopes rather than residual photons [EPRI PWR Primary Water Chemistry Guidelines; NUREG-1437][0].
I was on site for the mid cycle outage of three mile island unit 1 around 2005. I did the data sync and transfer for the steam generator inspection, but got tutored by some old PHDs during the down time.
[0] https://downloads.regulations.gov/NRC-2020-0101-0142/content...
It was a quote of the linked article:
"Holtec International, which owns the closed nuclear facility, reported the worker was a contractor who was wearing all required personal protective equipment, including a life vest while working near the pool without a barrier in place."
From the linked xkcd in various threads it seems like a life vest should keep you in the "safe" zone
However it doesn't actually say how much is safe to drink
the deeper you get, the worse for you. I assume the first second was critical.
The usual reason for this is it keeps your mouth from being far from the air. In this case it also helps because the radioactive stuff is close to the bottom. And exposure depends on distance from the bottom.
He was not working in a volcano.
On a tangent, I kinda love the fact that I've learned more about nuclear physics, orbital mechanics, and relativistic speeds from a poorly drawn webcomic than I have from any other source. (Ok KSP might actually have xkcd beat on orbital mechanics)
There are also plenty of jobs where people are in close proximity to insanely hot/dangerous liquids.
If said junk was alpha- or beta-emitting, it could be enough of a danger for cancer.
Wow, people are really clueless about how nuclear power plants really work. They literally wrote up a safety report and transported them off-site.
Wow, people are really clueless about how to avoid reacting angrily. It's funny to append "they were wearing a life vest" to "they had a nuclear safety accident"
(Am I doing it right yet?)
Edit: ok, I’m probably the fiftieth person to point this out. It’s still a good video.
I used to work at UC Berkeley, and one of the buildings on campus previously held a research nuclear reactor (https://en.wikipedia.org/wiki/Berkeley_Research_Reactor). There's a sign there now "Nuclear Free Zone"; (https://www.dailycal.org/archives/the-berkeley-nuclear-free-...).
Note that they did have to do extensive decontamination on Gilman Hall (https://en.wikipedia.org/wiki/Formerly_Utilized_Sites_Remedi...) where plutonium was first isolated.
https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor...
Even drinking it I would think would be completely fine. The water itself doesn't get activated.
The linked report doesn't say how radioactive his hair is or give any indication of whether the person in question is threatened by this reading. Could be bad, could be nothing, we just know it is higher than normal.
EDIT The report below it seems to literally be "nothing interesting happened". The thresholds here for something to be reportable are very low. Frankly I don't know why this story is upvoted so much but I'm not about to make a bigger deal about it than one sentence.
I found this:
Days to receive chronic dose for increase cancer risk of 1 in a 1,000
432 (at 100 CPM)
86 (at 500 CPM)
But it's from a prepper site that doesn't cite their own sources.
I found this: https://www.energy.gov/ehss/articles/doe-ionizing-radiation-...
Which uses rem instead of cpm. An on-line converter of unknown quality says 300 cpm is 500 rem, and the pdf from the .gov site says 500 rem is "death probable in 2-3 weeks", but I think that chart is saying that's whole body & no therapy. Where this is probably mostly hair that can be just cut off totally let alone washed, and so the elevated exposure is probably both low and short duration, and medical therapy (whatever that means, if any in this case) on top.
I can't tell, could be the same as just visting a country with a slightly higher background that isn't a problem for anyone, to dead in a month. Leaning towards no problem just because of the short time and apparently mostly external and removable source.
However, it's not nothing either. It's maybe no problem for this person only because they avoided ingesting the water and the water was very quickly washed off and presumably their hair was cut off and all clothes etc removed as fast as possible. It's clearly at least "rather hot" and you can't just play in it and have prolonged exposure and ingestion. It doesn't seem to be "basically zero".
Assuming this website was used, it looks like it does a naive multiplication by 5/3, which seems... simplistic? The rest of the page doesn't exactly fill me with confidence either. No indication of how the conversion factor was derived and there's a bunch of links to other CPM -> <radiation-related unit> calculators. On top of that, the landing page for the root domain boasts about AI capabilities and their AI page prominently features "Elevate Your Content Creation" and "Generate high-quality AI content with ease!"
[0]: https://www.inayam.co/unit-converter/radioactivity/counts_pe...
It's worth noting that humans are typically radioactive to the level of 3 kBq, or 3000 disintegrations per second, so if I ever realised I had 300 cpm of radiation on my skin as measured by a device that is sensitive to alpha, beta, and gamma, I probably would just shrug and wash it off. Where it might be a problem is if I am dealing with only alpha and beta isotopes, and I'm getting 300 cpm on a gamma-sensitive detector, meaning that the _secondary radiation alone_ is 300 cpm.
(Realistically, I and the radiation safety officer overseeing whatever I was doing would be in serious trouble and have a ton of paperwork, but I just mean it in the abstract)
I mean, 10 grams of potassium has ~300 Bq (that is 300 disintegrations per second) of radiation, so I think I should be able to get my hair far more radioactive than 300 cpm on a beta-sensitive geiger counter if I just slather myself in low-sodium salt from the grocery salt. The salt might be bad for my scalp, I don't know, but the radiation is fine. My point here, though, is that I don't know what equipment the 300 cpm is measured with, what the thresholds are and what the window material is, and that can change things greatly, but my non-professional opinion as the wrong kind of doctor is that it's...probably not a big deal.
We've actually used KCl as a low-level radiation source before, and we joked that when the experiment is done we can just take it home and use it to season dinner.
Tritiated water is a reality of reactor pools.
the primary hazard from acute, high-dose uranium ingestion is chemical toxicity leading to acute kidney failure (nephrotoxicity), not radiation.Emily Austin, Hilary S. Myron, Richard K. Summerbell, Constance A. Mackenzie, Acute renal injury cause by confirmed Psilocybe cubensis mushroom ingestion,
Medical Mycology Case Reports, Volume 23, 2019, Pages 55-57, ISSN 2211-7539,
https://doi.org/10.1016/j.mmcr.2018.12.007. (https://www.sciencedirect.com/science/article/pii/S221175391...)
Abstract: Psilocybe mushrooms are consumed for their hallucinogenic properties. Fortunately, there are relatively few adverse effects associated with their consumption. This is the first reported case of acute kidney injury (AKI) secondary to confirmed ingestion of Psilocybe cubensis mushroom. A 15-year-old male developed symptomatic AKI 36 h post-ingestion of Psilocybe cubensis mushrooms. He was admitted to hospital with hypertension, nausea and abdominal pain and a creatinine of 450 mmol/L. A sample of the crop of mushrooms was confirmed by mass spectrometry to contain psilocin. On day 5 post-admission, he was discharged home. Outpatient follow-up confirmed complete resolution of his renal function.
Keywords: Psilocybe; Nephrotoxicity; Mushrooms; Kidney injury
I wonder if there was an accidental polyculture issue, either with a different mushroom or a freak mutation that caused that particular shroom to synthesize toxic compounds. When growing directly from spores, you get mixed genetics, so your various mushrooms will grow slightly differently (if you want consistent genetics you grow clones from an isolate via agar plate or tissue sample from fruiting body).
This is well researched and just like with semaglutide I believe a big part of the population should take daily tadalafil.
Better cardiovascular health, more erections and many positive downstream effects (lower E:T ratio, weight loss) that are beyond the scope of this comment.
The health benefits of exercise are most likely due to improved blood flow and related physiological effects. In principle, pills could theoretically achieve similar outcomes by enhancing circulation or other underlying mechanisms.
Not taking sides here, just reasoning out loud.
I suspect you’re not going to find a pill or combination of pills that can achieve those outcomes. And again, we’re ignoring the mental health benefits.
Rejecting all evidence, denying observations, and leaning heavily on half-baked hypothesis that culminate somehow on a gotcha. That sounds an awful lot like something someone who "does their own research" would say.
Yes, extreme levels of high-intensity exercise have adverse side effects. Cross-fit and rhadbo is an example.
https://en.wikipedia.org/wiki/Rhabdomyolysis
Drinking water also does everyone good, and everyone's health will improve if they increase their water intake, but drinking water in excess can also be fatal. Does this mean that the idea that drinking water does you good "does not make a priori sense"?
No, it doesn't.
however any kind of "pill" that would have anywhere near the same health effects as exercise is decades away at least.
hips and knees acls tend to be a failure point but the non-existance of said "pill" is probably a fairly big tick for the excercise side, and our tech for repairing those failure points continues to progress at speed
Yes, overtraining is possible (and not infrequent, particularly by those who fail to read or ignore the evidence). But an absolutely sedentary lifestyle is exceptionally fatal.
Medications (as with exercise) come with both intended and unintended consequences, as well as costs and inconveniences. Generally the more extreme the condition you're treating, the more likely that medications will carry some of these disadvantages (e.g., chemotherapy against cancer, where the goal is often to kill the malignancy at least slightly faster than one kills the patient). Exercise operates through complex feedback cycles and mechanisms, not all of which are well-understood (as an example, why muscle grows in response to strength training being a fundamental case despite much information on how muscle responds to which specific training protocols). Medications can amplify training response (e.g., anabolic steroids for strength training athletes), but often don't by themselves substitute for it.
This is why, in a broader sense, that the Baconian scientific method does not rely simply on a priori hypotheses, but tests these with experiment and evidence, that is, empirically. The ultimate critique of pure reason is that whilst it can be a useful guide for what you then want to test empirically, it has a phenomenal tendency to lead one to utterly fallacious and/or irrelevant conclusions.
One of the more robust sets of evidence on both the negative effects of a zero-stress lifestyle and of the benefits of regular cardio and strength training is that accumulated through long-term space missions, largely aboard the International Space Station (ISS). Microgravity would be the ultimate low-stress environment, and it turns out to be seriously harmful. Astronauts there are tested before and after missions, with various measures of fitness loss. With time-in-space being an immensely valuable resource, astronauts also spend two hours per day engaged in physical exercise (<https://www.asc-csa.gc.ca/eng/astronauts/living-in-space/phy...>), or 1/8 of their waking schedule.
Online, ExRx (<https://exrx.net/>) has a large library of fitness information, including a list of online journals (<https://exrx.net/Journals>) and expert talks (<https://exrx.net/Talks>). Good books on fitness will link to research substantiating recommendations (Lou Schuler's New Rules of Lifting series is a good example of this).
The best results are achieved when these are working together toward some health or fitness goal. It's far more effective to align your lifestyle, diet, exercise, and medications than to have these working against one another (I'll take this pill to compensate for my drinking / smoking / drug use / pollution exposure / stress, etc.). Of course, that's not always possible, and there are circumstances where it's difficult or impossible to attain some of these mechanisms (parapalegic, living in a highly polluted environment, inherently stressful living conditions, GI compromise limiting eating or diet, congenital or genetic conditions or predispositions). Even here, if the patient can make some progress in a specific modality, they'll probably see some benefit.
Some of the most impressive athletes I've seen, from a sheer grit perspective, are those who are working against some major limitation: the swimmer at a health club long ago paralyzed in both legs, the one-legged open-water swimmer, old farts with their pacemakers showing through their chests swimming in the San Francisco Bay, patients with diabetes, heart failure, Parkinsons, recovering from cancer, with various injuries or scars, still at it. Some are astonishingly good by any measure, many aren't, but damned if they're not trying and generally living far better than if they weren't.
This isn't "don't take your meds", it's "use all the available tools". Lifestyle, diet, an exercise are underrated and powerful tools.
"You don't look like your medical history" is a high compliment coming from a doctor, and I'd strongly recommend earning it.
Agreed - low dose daily cialis/tadalafil (e.g. 5mg/day) is very common among elite athletes, bodybuilders, etc. As are GLP-1's despite elite athletes rarely being overweight.
Tadalafil is taken for its endothelial benefits (erections are a convenient side effect), and GLP's for its nutrient partitioning and insulin sensitization effects.
Medications are very often most effective when paired with good lifestyle habits, rather than one of the other.
It also depends on what your goals are, obviously.
Beyond that, if goals are for specific performance targets, in some athletic or competitive activity, you'll want to tune your training toward that. Again, the baseline is remarkably consistent, it's the high-performer tuning which varies.
Going off-label on prescriptions, especially without a doctor's supervision, carries its own set of risks. If you're lucky, it's only wasted money. If you're not, it's markedly worse.
The biggest hurdle I've encountered personally is primary care doctors deal with very sick people every day (terrible diet, terrible body composition, terrible alcohol/drug habits, etc). And that's who they optimize their care for.
If you show up to a PCP and you're in shape, all vitals on point, all bloodwork looking good, the last thing the PCP wants to do is prescribe anything because "you don't need it" and "you're not sick".
Most doctors simply don't care about helping you optimize your health once you've reached "healthier than average" status.
This leads a lot of people to doing their own research, and finding health clinics outside of insurance that cater to health optimization, anti-aging, and non-standard treatments (like prescribing GLP's to people who aren't overweight, or Cialis for people who don't have ED). These clinics also aren't very good because, while they are indeed doctors or NPs, they make money off selling you prescriptions, so they are biased and usually push medications you might not really need or want. (Which again emphasizes the importance of self-education and doing your own research).
For drugs like GLP-1's, there are a whole lot of anecdotal benefits outside of weight loss. The problem with the drug industry is once a drug is approved for its most profitable use case, drug makers don't bother to pursue additional FDA approvals for additional indications because the headache isn't worth the (marginal) extra revenue.
I very much wish there were a category of doctors specializing in treating healthy people looking to optimize their health further.
"Sports medicine".
<https://my.clevelandclinic.org/health/articles/24627-sports-...>
<https://en.wikipedia.org/wiki/Sports_medicine>
You might also look into nutrition and dietetics and exercise physiology. If you're looking at cognitive function, neuropsychology and possibly some psychotherapy specialisations.
"Wellness coaching" is starting to get into the woo / overly-self-interested / conflicted domain, though there are probably a few good apples. I'd proceed with extreme caution however. There are plenty of docs who're more than happy to provide what a patient asks (and is willing to pay top dollar) for.
Every person has a limit of how much time and energy they can put into exercise. If they can go beyond that with a pill (with no other cost), why wouldn't you want everyone to take it?
One of many, looking at just one detail (sitting): https://www.health.harvard.edu/staying-healthy/sitting-may-i...
From a personal experience, so it's just a guess, a contributor may be fluid movement in the body. Fluid in blood vessels are pumped directly, but must fluid is not in blood vessels. The heart has a diminishing effect outside the vessels (capillaries have small holes to let water and small molecules through into extracellular space, and then to collect it back, rest goes through the lymphatic system which also drains back into the bloodstream). Muscle and body movement helps. From what I experienced and experimented, just walking did a lot more than running. I focus on this specifically due to personal health experiences that I don't want to go into that let me feel a clear difference, where intensive running did hardly anything but then just walking did, an experiment I performed during a period of my life when "getting stuff out from all over my body" mattered.
Personally, I choose to run only when my brain/body tell me to, when I feel like it. Definitely not when I would have to fight myself to get going. (If your body/brain tells you the opposite then it is what it is, personal feel over generic advice)
5mg daily tadalafil is fine for me though and that‘s also the normal daily dosage.
https://www.youtube.com/@USCSB/videos
Not necessarily nuclear (since chemical and industrial accidents are much, muhc more likely), but highly recommended if you're interested in such incidents and their causes.
But just now I read that a (sharply reduced) budget had passed the house? [2] does anyone know what the current state is?
[0]: https://www.csb.gov/assets/1/6/csb_cj_2026.pdf
[1]: https://www.pbs.org/newshour/show/only-federal-agency-that-i...
[2]: https://www.safetyandhealthmagazine.com/articles/27090-house...
The non-emergency classification is bureaucratic nonsense. This is an internal contamination event with unknown but potentially severe consequences.
> 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.
This might be 500+ MBq (0.5 GBq). Yeah it's a different isotope, but clearly not a "non-emergency"
EDIT: (after 1 hr) - Litvinenko dose was 4GBq - I was wrong by 3 orders of magnitude. My bad
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.)
https://github.com/arthurcolle/Ronald-Colle-Papers
I love how punchy you are! And the astronomy photos. Take care :)
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.
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.
Are you qualified to make the statement I'm replying to?
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.
You very much do, if you're calling into question the statements in the article that it's fine.
Further, your reasoning is biased towards safety (rather than risk), which seems completely sane.
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.
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.
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.
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.
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.
Story checks out. I think this would pass.
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.
EDIT: 300-600 CPM above background radiation levels is for EXTERNAL environmental monitoring, not for POST-DECONTAMINATION readings on a contaminated person.
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.)
There's even an XKCD "What if" about it. https://what-if.xkcd.com/29/
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.
The USNRC is currently not operating normally due to the government shutdown. Perhaps that has something to do with it.
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.
> Why report the ambiguous "300 CPM" instead of an actual dose estimate in mSv/μSv?
> Is there any legitimate reason to report CPM instead of dose after a contamination event?
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).
[0] https://www.nrc.gov/reading-rm/doc-collections/cfr/part050/p...
[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.
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."
Here, take METAR as an example. This is broadcast on open airwaves and every pilot can read this. Here's the latest one from KSFO[0]
METAR KSFO 260756Z 29004KT 10SM SCT012 BKN042 16/14 A3007 RMK AO2 SLP183 T01610139 401890133
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)
Don't confuse "public" with "for you"
> 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
I love this book. Randall is such a gifted artist
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
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.
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.
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 :)
Sufficient to say that you'd be very popular, but in probably the least fun way possible.
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.
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.)
I guess in a nuclear reactor there is a lingual shift and the word emergency cant be used for just any old 911 call.
Like how Australians apparently call a jellyfish bite "uncomfortable"
https://www.reddit.com/media?url=https%3A%2F%2Fexternal-prev...
https://www.abc.net.au/news/2014-04-08/vinegar-makes-box-jel...
If you ever become prime Minister of Australia, and find yourself on an oceanside bombing range, don't go spear fishing.
Not sure about spiders. Are their fangs considered to be teeth? Platypus have venomous spurs, not sure what that’s called.
If you fell in a lake and accidentally ingested some wayer known to contain some pathagen dangerous to humans, you might seek medical care, but I don't think most people would consider that an emergency. This is similar.
In this case, not much. It's still an exposure event and absolutely worth giving medical attention to assess continued exposure levels from ingested contamination and generally be overly cautious. But that doesn't mean it's ultimately going to be a significant factor in this workers risk for radiation induced disease. It's certainly better than living in the vicinity of coal mining and processing plants.
the thing is that this type of "violation" can easily be prevented by including the obligatory showering or shaving as part of the contract, so either they consent or they didn't end up in a position where they can be exposed to radioactive matter.
So this can not explain why the hair wasn't shaved.
https://www.reddit.com/r/LiveFromNewYork/comments/1bh2edu/th...
I'm essentially pro-nuclear, I just don't trust people who run it.
https://www.nrc.gov/docs/ML0534/ML053410342.pdf
NRC is a good place to start. They have been at trying to prevent tech from hurting people for awhile.
There is essentially zero risk to the operation of the plant (or this worker!) from such an event.
Imagine if oil and gas facilities were required for any worker fall to have federal government workers visit onsite, draft a report for review, have it examined by expensive niche lawyers with rounds of revisions, and then have it published it publicly.
This is just a silly example of the hysterical safety-ism involving anything nuclear-related in the US.
Yes, working in any job related to energy carries risks. Just ask a roughneck, lineman, or wind turbine installer.
Among other things, he had to sit inside an enclosure made of scintillator material for a period of time, to make sure he wasn't contaminated. Then he also got blood tests for heavy metals etc. They pretty much went by the book for all of these tests.
Also, the facility is the only place that's equipped for this kind of situation.
Doing it often doesn’t really add to the cost. More reporting is helpful because it explicitly makes it clear even operational issues can have lessons to be learned from. It also keeps the reporting system running and operationally well maintained.
WebPKI does this as well.
It's important to identify even small defects or incidents so that patterns can be noticed before they turn into larger issues. You see the same breaker tripping at 3x the rate of other ones, and even though maybe nothing was damaged you now know there's something to investigate.
Sea-drilling rigs (oil) have far more potential for environmental damage than modern nuclear plants
Yet they have no federal public register for when a worker falls overboard (an incident far more likely to result in death).
Key word: "modern". A key aspect of a modern nuclear plant, that supports its high level of safety, is the required incident reporting and followup.
The relevant issue is not really about a single worker being injured or dying. It's about detecting safety issues which could lead to a catastrophe far beyond what a sea oil drilling rig can, at least when it comes to human life and habitability of the surrounding area.
For example, after Chernobyl, much of Europe had to deal with contamination from cesium 137.
The entire planet's geological history shows when the nuclear age started, because humans are irresponsible in aggregate. (See also global warming.)
> Aaaand it’s this alarmist attitude ...
You're providing an object lesson in why humans can't really be trusted to operate systems like this over the long term.
Ironically so are you. The coal we burn puts far more radioactivity into the environment than nuclear plants do. Yet we make sure nuclear isn't viable and burn coal like crazy. We do this only because of the type of risk telescoping you are doing. If you do a rational risk assessment, you will see that even operating nuclear plants as shown in the Simpsons would have less risk than what we are doing now. There is a risk to doing nothing. You are missing that part in your assessment.
A worker falling into a reactor pool (which is just room temp water with very little risk) is not a catastrophe, yet due to the absurd safetyism surrounding nuclear it requires a federal report.
We don’t require this level of cost insanity for far more deadly worker events at oil, gas, solar or wind facilities.
There is no systemic risk from worker falls. MAYBE the plant in question should address hand railing heights from pre-ADA construction. It certainly shouldn’t require multiple federal government employees to create a report on it and be publicly listed in federal register and reported on by hundreds of news outlets.
You’re making my point.
This is not saying what you think it's saying.
When an oil rig has an incident, cities and hospitals and food storage and logistics aren't disrupted.
> What if I took a swim in a typical spent nuclear fuel pool? Would I need to dive to actually experience a fatal amount of radiation? How long could I stay safely at the surface?
> Assuming you’re a reasonably good swimmer, you could probably survive treading water anywhere from 10 to 40 hours. At that point, you would black out from fatigue and drown. This is also true for a pool without nuclear fuel in the bottom.
> “While performing work inside the containment building, a Palisades contractor fell into a pool near the reactor that contained clean, borated water,” O’Brien said.
From https://www.mlive.com/news/2025/10/michigan-nuclear-plant-wo...
TL;DR you're always getting some ionizing radiation, how much matters.
Are you sure about that? 6200 mSv is 6.2 Sv, which I understand to be near-universally deadly. That dosage would be profoundly incompatible with the news that the worker was being sent offsite to seek non-emergency medical attention.
Poking around, it looks like "counts per minute" have to get converted to a dosage using an instrument-specific formula. I CBA to go find that formula, but you're quite welcome to.
Would you provide a link to the source of this average instrument specific rate?
I'm interested in knowing which instruments designed to detect low-to-medium-level radiation sources on a human are configured so that five detections per second would equate to a "You're fucking dead; there's really no hope for you" dose.
(Did you ask an LLM to "convert counts per minute to mSv" and fail to sanity-check the confident-sounding result it gave you?)
> ...everything emits...
Given that the crust and sea and air of this planet are chock full of radioactives, and that every living thing on the planet builds itself out of that material, that goes without saying.
PS 300 CPM is nothing. There are places where people live where the natural background radiation is higher than that. Also, background radiation is mostly Gamma rays which is more dangerous than what comes off of fission products or nuclear fuel.
That depends on the instrument. It's an instrument-specific rate. I'd say that saying "300 CPM is nothing" absent any information other than the CPM is foolish.
As I indicated earlier, given all of the other context we have, we can reasonably suppose that 300 CPM from whichever instrument was used in this incident is nothing to be concerned about.
There are 4 types of ionizing radiation: alpha, beta, gamma/x-rays and neutron flux. Each one has a different rate it is blocked by different materials (water, air, etc). Each one has a different risk to people. You have to compute counts per unit time emitted from a point source for each of the different types of radiation. Then you have to compute the amount of "arc" the person is in. Then you have counts being absorbed and you next multiply each count by a fixed factor depending on the type of radiation. This final number gives you total Greys per unit time, then you then have to divide by the mass of the person. Then you multiple that number by the total amount of time and that gives you total Greys absorbed. That's the number you use to assess risk to the person. For reference, this guy probably got less than 1 Grey. Someone getting radiation treatment for cancer might get 75 Greys.
So please stop trying to calculate this stuff yourself. I'm pretty sure you are doing it wrong. This guy will be fine.
PS Sieverts are a physical measure, Greys are a measure of biological "harm".
The US's NRC disagrees with you. From [0], they say this about the sievert and rem:
Dose equivalent
A measure of the biological damage to living tissue as a result of radiation exposure. Also known as the " biological dose," the dose equivalent is calculated as the product of absorbed dose in tissue multiplied by a quality factor and then sometimes multiplied by other necessary modifying factors at the location of interest. The dose equivalent is expressed numerically in rems or sieverts (Sv) (see 10 CFR 20.1003). For additional information, see Doses in Our Daily Lives and Measuring Radiation.
Dose, absorbed
The amount of energy absorbed by an object or person per unit mass. Known as the “absorbed dose,” this reflects the amount of energy that ionizing radiation sources deposit in materials through which they pass, and is measured in units of radiation-absorbed dose (rad). The related international system unit is the gray (Gy), where 1 Gy is equivalent to 100 rad. For additional information, see Doses in Our Daily Lives and Measuring Radiation.
Dose equivalent (or effective dose) combines the amount of radiation absorbed and the medical effects of that type of radiation. For beta and gamma radiation, the dose equivalent is the same as the absorbed dose. By contrast, the dose equivalent is larger than the absorbed dose for alpha and neutron radiation, because these types of radiation are more damaging to the human body.
> 6.2Sv in a single year is probably less than average for a human from background radiation.
Are you sure about that? <https://xkcd.com/radiation/> claims 4 mSv per year as normal radiation dosage, and 50 mSv per year as maximum permitted annual dosage for "US radiation workers", whatever that means.
I think you're off by a factor of a thousand for the typical exposure level and off by a factor of a hundred for the exposure level where they stop letting you work near the radioactives for a year.
[0] <https://www.nrc.gov/reading-rm/basic-ref/glossary/full-text>
[1] <https://www.nrc.gov/about-nrc/radiation/health-effects/measu...>
"Dose absorbed" is a physical measure of ionizing radiation that is directed at something. That's measured in rems or sieverts (or Grays, notice the spelling). "Dose equivalent" is a medical measure of the risk caused by that "Dose absorbed". That's measured in Greys (with an E, not an A). Both those measures combine the count rates for the 4 different types of radiation into 1 amount. "Dose equivalent" goes farther and is meant to calculate medical risk to a living person. Even more confusing there is a Gray (dose absorbed) and a Grey (biological impact of a dose absorbed, or dose equivalent); they are different.
The part about beta and gamma radiation is about establishing a baseline for converting between the two units but should never be used for calculating "dose equivalent" in practice. Its how we determine the value of 1 Grey. It isn't a way to convert from "dose equivalent" to "dose absorbed".
I'm trying to simplify this stuff for an audience without the necessary background information. Doing that requires me cutting out a bunch of details. The NRC text on the other hand is technically precise but also is mentioning a lot of things that are true but confusing or only useful for calibrating instruments. They are also explaining one tiny part of this and you left out the parts where they talk about how to combine the different counts for each type of radiation into one measurement. That's something else I'm also trying to explain at the same time. So I'm covering more ground and trying to do so with simpler terms. That's going to mean you can cherry pick stuff but doing that will to give you the wrong impression.
Natural background radiation varies by location on earth by a factor of 300. That 4 mSv per year is for natural background radiation at the low end of the scale which happens at sea level in places without Uranium or Thorium deposits. However, there are places where people live (and have lived for 1000s of years) where the natural background radiation is 300x that amount or about 1.2Sv/year. There is no observed increase in cancer rates in those locations despite decades of study. I'm also assuming that the "normal person" will take a flight or two and potentially be near other sources of radiation without knowing it (like your smoke detector).
PS The 50 mSv/year number is absurdly low. Its one of the main complaints about how the NRC handles nuclear radiation. Its literally lower than the natural background radiation at sites in India and Brazil.
Neither the NRC nor the EPA nor the NIH nor the NRC seems to know about the "Grey". Everyone in the US seems to know about the "Gray" (abbreviated as "Gy"), which is used to measure dose and doesn't factor in biological harm.
What country uses the "Grey" unit? What's the abbreviation of the "Grey" unit? Would you point to credible sources for the answers to those two questions?
> "Dose equivalent" goes farther and is meant to calculate medical risk to a living person.
Yes. That's biological harm. Getting hit on the skin from outside your body with a large amount of alpha radiation is far less harmful than getting hit with the same amount of gamma radiation. AFAICT, "dose equivalent" is measured in Sv or rems.
If you can demonstrate a credible source for the "Grey" unit, then I can dismiss this as a time-wasting misunderstanding, but I've yet to see any reference to a "Grey" unit of radiation exposure.
> Its literally lower than the natural background radiation [at some places on earth]...
Yep. ALARA is a scourge. And I -too- have read Admiral Whatshisface's open letter from the 1980's or 1990's or whenever about how the regulation of the civilian nuclear energy program is batshit nuts by way of being negligently overcautious.
They will still try to decontaminate you of any radioactive materials they can scrub off as a matter of course, but 300 counts per minute, while noticeably higher than background radiation levels, is pretty benign in the grand scheme of things. The fact that you can still count individual radioactive emissions is incredibly good news compared to how bad things could be.
Especially since the reactor will have been shutdown for some time by definition, if the reactor cavity is open enough to fall into. Hopefully the low rate of radioactivity evidenced by the counts on the person's hair is matched by the level of radioactivity in the water.
And on that note, medical attention would also be provided as a matter of course after a fall like this, but it seems to me that the physical injury of falling some distance and possibly hitting metal on the way down is going to be more of a danger than the radiation, especially compared to the sources of radiation people naturally run into (especially cigarette smoke, whether primary or secondhand).
The NRC would make you attend training and get decontaminated if you had to cross a street if they operated the roads.
This sort of place is safe enough to bring your kid into without significant precautions (I got to do this as a kid—it was really cool). The biggest risk by far is drowning.
Relevant XKCD: https://what-if.xkcd.com/29/
0) If you've not read this chart, do carefully read it: <https://xkcd.com/radiation/>. If you've read it before, take some time to carefully re-read it.
1) The guy's getting sent off to seek non-emergency medical attention. I bet you an entire American Nickle that that attention is almost entirely for injuries sustained in the fall, rather than for radiation exposure.
Or to put it another way, 300 CPM (which is a rate) is less than how much radiation you get when on a flight, or how much radiation you get at higher elevations. Even giving a simple explanation of how to calculate Greys (the actual measure you are looking for) takes up the better part of a page. Hell, your bones are radioactive. Yet there are plenty of people posting that somehow the risk to this guy is radioactivity. In reality, his biggest problem is probably going to be finding a new job.
For his job, depends on the dose he took. In my country he would have been on benefits until the dose was calculated, then if possible, reintegrated in the team, or directed towards a new job if not (paid formation and everything). I've studied with a diver who couldn't work with radioactive trash anymore, he wasn't meant to be a SWE in the end, he now dive for unexploded WW2 stuff in the north sea/Baltic I think
https://cns.utexas.edu/news/research/coal-power-killed-half-...
FITNESS FOR DUTY (FFD) EVENT
The following information was provided by the licensee via phone and email:
"On 10/25/25, at approximately 1230 EDT, 3 empty alcohol bottles were found in the protected area by a contract employee. Site security was notified and took possession of the empty bottles which were removed from the protected area. The individual who accidentally brought in the empty alcohol bottles with other non-alcoholic empty bottles was tested for FFD and was negative. This event is reportable in accordance with 10 CFR 26.719(b).
"The NRC Resident Inspector has been notified."
Yes, it is tiring. In this case, not really because it is at least for me, humorous in a Doc Martin sort of way. But elsewhere and on places like Reddit where the pedantry is often at best unjustified and at worst, wrong, it has made me spend less time on the sites.
Isn't it much worse internally than hitting your outer skin?
The issue with ingesting deuterium/tritium is that the dose will now have to be calculated/estimated per organ, and while I don't remember exactly how it's done, it's more complex than calculating the mSv he took (I can't give you more details, I'm not competent, I've observed a radiologist a week my bachelor year to decide which master I would do, I'm now working in software which should tell you everything)
Meanwhile, in Texas, 1.5 people die every day working in Oil and Gas extraction.
A few people die every year installing or falling off of wind turbines.
But by all means, let's make this a news story instead and keep making nuclear sound scary. I’m sure the person who posted this to HN with this clickbait title has zero political beliefs.
https://ourworldindata.org/grapher/death-rates-from-energy-p...
All that disclaimer aside: a banana produces about 15 Bq (which is s^-1), i.e. 900 cpm.
Unfortunately radiation medicine is pretty complicated and the report gives us very little info, presumably mostly because they don't have very much info. It will take some time and effort to establish more.
What we do know is that they measured 300 CPM at the person's hair, which was probably where they expected the highest count due to absorbed water (likely clothing was already stripped at this point). CPM is a tricky unit because it is something like the "raw" value from the instrument, the literal number of counts from the tube, and determining more absolute metrics like activity and dose requires knowing the calibration of the meter. The annoying thing here is that radiation protection professionals will still sometimes just write CPM because for a lot of applications there's only one or a handful of instruments approved and they tend to figure the reader knows which instrument they have. Frustrating. Still, for the common LND7311 tube and Cs137, 300CPM is a little below 1 uSv/hr. That wouldn't equate to any meaningful risk (a common rule of thumb is that a couple mSv is typical annual background exposure). However, for a less sensitive detector, the dose could be much higher (LND7311 is often used in pancake probes for frisking because it is very sensitive and just background is often hundreds of CPM). Someone who knows NRC practices better might know what detector would be used here.
That said the field dose here is really not the concern, committed dose from ingesting the water is. Ingesting radioactive material is extremely dangerous because, depending on the specific isotopes involved, it can persist in the body for a very long time and accumulate in specific organs. Unfortunately it is also difficult to assess. This person will likely go to a hospital with a specialty center equipped with a full body counter, and counts will also be taken on blood samples. These are ways of estimating the amount of radioactive isotopes in the body. In some cases tissue samples of specific organs may be taken.
I believe that the cavity pool water would be "clean" other than induced radioactivity (activation products from being bombarded by radiation). Because water shields so well the pool should not be that "hot" from this process. Most of those products have short half-lives which, on the one hand, means that they deliver a higher dose over a shorter period of time---but also means they will not longer forever and are less likely to be a chronic problem if they are not an acute one.
I suspect this will get some press coverage and we will perhaps learn more about the patient's state.
Another way we can get at this question is by the bureaucracy of the notification. An 8-hour notification as done here is required in relatively minor cases. Usually for a "big deal emergency" a one-hour notification is required. The definition of such an emergency depends on the site emergency plan but I think acute radiation exposure to a worker would generally qualify.
As others had said, more alarming part is that they ingested the water, which could go like defected Russian spy Alexander Litvinenko. But it could also be like man eating few bananas seasoned with expired Himalayan salt. The report just doesn't say how much of what was ingested.
If you're asking why it's interesting for HN, I think it's actually because people are fascinated with nuclear, in a positive way.
⇒ the “non-emergency” classification isn’t about the “fell into a nuclear reactor pool”, but about sending the victim off site.
And the reason the contamination transport off-site was classified as non-emergency was because even though the amount of radiation detected on the guy is less than he'd have gotten from flying in an airplane; nuclear safety standards are so unbelievably rigorous and strict that even that small of an incident needs to be reported; even if it presents absolutely no danger to anyone anywhere (not even the guy that was contaminated) and hence is classified as a non-emergency notification.
They returned to work the next day with minor injuries due to the fall. It doesn't sound like it was an emergency to me.
Hair contaminated
Roughly 10x background radiation.
So like two weeks of sunshine in a day.
Not a good day. Not fatal.
In other news, a kitten named millicurie did a really adorable thing.
The only remarkable fact here is that the regulatory structure is strong enough that we commoners are entitled to hear about it. That's a Very Good Thing, and one I wish we enjoyed apropos, say, the corporate veil (looking at you, Chevron, Exxon, Shell, Aramco, Sinopec, Amazon, Oracle, AIPAC, United, The Trump Organization, X Corp, Paramount, Skydance, eMed Population Health, Inc., et. al.).
But the story here is a guy fell into some water, and is following SOP (which is also a Very Good Thing).
Please don't feed the clickbait.
> The reality is much more positive than the myth, with all three men escaping such a grisly fate. Indeed, Alexei Ananenko and Valeri Bespalov are believed to be both still alive as of 2024, while Boris Baranov lived until 2005 when he passed away from heart disease.
Source: https://www.history.co.uk/article/the-real-story-of-the-cher...
Reports don't mean danger, and they don't mean lack of control. Reports are information.
I'm also not totally against nuclear, in case you are suspecting that. I do think though, that we as a society aren't at the point where we have the ability to completely control such technology, contrary to what proponents of much higher utilization of nuclear like to claim. Reports of fuses seemingly without failover or stolen equipment seem to support that argument.
Accidental swimming is no fun, I wish the guy a full recovery from dihydrogen monoxide poisoning.
The reactor vessel can contain heavy water or water with boric acid in it, neither of which are good for you. Additionally, neutron radiation from the reactor will cause the formation of radioactive tritium in the vessel water, so the liquid itself becomes radioactive.
I find it highly informative that the required PPE for working in that location is a life jacket so you float in case you fall in, rather than a tether and fall arrest harness so that it's not possible to fall in.
300 CPM is nothing, background levels might be 150.
He went back to work the next day. They don't provide much detail about the minor injuries but it seems that the biggest issue is maybe a bruised shin from the fall.
Wow
This incident report says that the worker fell into a "reactor cavity" containing water and that there was a measurable amount of radiation detected in their hair after the initial clean-up. The two situations don't seem remotely compatible to me.I agree this was not a serious incident, and I never really though it was. (I'm extremely pro-nuclear, for the record.) But at the time I posted, the comment section was about 8 people posting the xkcd link at once (with no additional commentary), and few others reading it and saying "oh, no problem then", with literally nobody pointing out the discrepancies, or explaining exactly what a "reactor cavity" means in this context.
(Not exactly same but close)
How dumb do you have to be to not only fall into it but to also swallow it...