The rest of the event reports are also very active. Reactor sites are fun places to work.
A worker fell into a nuclear reactor pool
231–240 of 545 posts
Re: A worker fell into a nuclear reactor pool
#232Earlier quoted context omitted.
I personally consider an area dangerous if I need to undergo radiation decontamination after entering it, continue emitting radiation after decontamination, and need to seek medical attention. Maybe the nuclear regulatory bodies have differen definitions?
I get a feeling that there are a lot of people trying to minimize this incident for some reason.
I get the feeling that you don't know how complicated calculating radiation exposure is. There are plenty of interest in fear mongering against nuclear. Almost all the people talking about how much radiation 300 CPM is have absolutely no idea what they are talking about. Some confuse total measurement units for rates; others are using just the wrong units; still others are talking about levels that are 1000x or 1000000x higher than 300 CPM.
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.
Re: A worker fell into a nuclear reactor pool
#233Earlier quoted context omitted.
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 medic…
> 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 o…
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."
Re: A worker fell into a nuclear reactor pool
#234Earlier quoted context omitted.
> They had 300 counts per minute which would e around 6200 mSv year 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 formul…
Rate matters. 6.2Sv in a single hour is fatal. 6.2Sv in a single year is probably less than average for a human from background radiation. The measurement units for ionizing radiation are very complicated and confusing. That's why people are told to not try to compute this stuff yourself. I have code that computes these units and conversions, its not simple. Here is a brief and simplified explanation of how you calcu…
> 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...>
Re: A worker fell into a nuclear reactor pool
#235Earlier quoted context omitted.
Aaaand it’s this alarmist attitude which is why we don’t have abundant cheap nuclear energy. 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).
> Sea-drilling rigs (oil) have far more potential for environmental damage than modern nuclear plants 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…
> 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.
Re: A worker fell into a nuclear reactor pool
#236Earlier quoted context omitted.
Why?
Because of all the other physiological and mental benefits that come from the exercise that the pill won’t give you?
It might be empirically sound, but it does not make a priori sense that exercising a body will improve it. If I use almost any object in the universe frequently, it typically degrades rather than improves.
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.
Re: A worker fell into a nuclear reactor pool
#237Earlier quoted context omitted.
People should probably try improve their CV health via exercise, rather than pills, wherever possible.
Why not both? 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?
Sure, but let’s start with promoting the 90 percenter rather than the 1 percenter then.
Re: A worker fell into a nuclear reactor pool
#238Earlier quoted context omitted.
Also it's in a way normalised to happen in a few places with beaches. There are vinegar stations every 100m or so. Basically a "yes, it will happen to a few of you". https://www.reddit.com/media?url=https%3A%2F%2Fexternal-prev...
Just fyi, they don't put vinegars at the beaches anymore, apparently it makes it worse (well I haven't seen any for a long while) https://www.abc.net.au/news/2014-04-08/vinegar-makes-box-jel...
Townsville's Strand has a number of them for example. (Really bad lighting, but I believe it's that green board: https://maps.app.goo.gl/x7gggCjGwxVqDBx79?g_st=ac) I went down the Qld coast a couple of weeks ago and they're still very common.
Re: A worker fell into a nuclear reactor pool
#239[dead]
Re: A worker fell into a nuclear reactor pool
#240Palisades MI reactor. Currently shut down and de-fueled but a restart of this reactor is apparently underway, with new fuel assemblies being delivered.[1] 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...
dunno if the life vest bit comment of yours was sarcastic, but it is a funny remark for sure :-) it sounds like "guy felt down in a volcano, but fortunately, he had a life vest"
Rather more like "Guy fell over looking into the volcano but fortunately there's a metal fence". The most immediate danger to you is that you'll drown because radioactive water is water and you can't breathe. So the life vest avoids this. In contrast volcanic lava absolutely can kill you before you drown, no problem.
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.