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"
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."
He was not working in a volcano.
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.
the deeper you get, the worse for you. I assume the first second was critical.
the primary hazard from acute, high-dose uranium ingestion is chemical toxicity leading to acute kidney failure (nephrotoxicity), not radiation.Even drinking it I would think would be completely fine. The water itself doesn't get activated.
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.
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.
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.
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/
> 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
> 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.
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.
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.)
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.)
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...
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.
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.
Not sure about spiders. Are their fangs considered to be teeth? Platypus have venomous spurs, not sure what that’s called.
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.
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).
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.
> 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.
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."
Isn't it much worse internally than hitting your outer skin?
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...
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.
All that disclaimer aside: a banana produces about 15 Bq (which is s^-1), i.e. 900 cpm.
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.
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.
⇒ the “non-emergency” classification isn’t about the “fell into a nuclear reactor pool”, but about sending the victim off site.
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.
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 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.
(Not exactly same but close)
How dumb do you have to be to not only fall into it but to also swallow it...