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Why is my dryer radioactive?

physics.stackexchange.com

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Re: Why is my dryer radioactive?

#131

Post by pfdietz »

schiffern wrote: post #129
pfdietz wrote: post #128

Earlier quoted context omitted.

Go back and read about the malfeasance of the petitioners there. They do things like cite a study, neglecting later data from the same study where the effect they want no longer shows up in the better data. Policy has to go beyond what is rigorously demonstrated. It's not like criminal law. Technologies are not innocent until proven guilty. Just because LNT cannot be demonstrated at the doses relevant to nuclear acci…

Claims of malfeasance go in both directions. >Policy has to go beyond what is rigorously demonstrated. Thanks. I can see we're done here.

Yes, indeed. We are done. You are living in a fantasyland, not in the real world of how regulation and politics actually work.

But at least you can admit LNT is consistent with the evidence? The claim to the contrary is an outright lie.

Re: Why is my dryer radioactive?

#132

Post by schiffern »

pfdietz wrote: post #131
schiffern wrote: post #129

Earlier quoted context omitted.

Claims of malfeasance go in both directions. >Policy has to go beyond what is rigorously demonstrated. Thanks. I can see we're done here.

Yes, indeed. We are done. You are living in a fantasyland, not in the real world of how regulation and politics actually work. But at least you can admit LNT is consistent with the evidence? The claim to the contrary is an outright lie.

[flagged]

Re: Why is my dryer radioactive?

#133

Post by schiffern »

caf wrote: post #117
schiffern wrote: post #38

Earlier quoted context omitted.

This claim (which ultimately came from the EPA) is suspect at best. It just comes from assuming a Linear No-Threshold model, which flatly contradicts the available body of medical evidence. https://youtu.be/TYZglUjLE0Y

It feels like this is something that should be easily amenable to statistical analysis. Large numbers of people get diagnosed with lung cancer; smoking rates vary widely and smoking is typically recorded in patient histories; typical radon levels vary widely with geography and are recorded / known. This looks like a near perfect natural experiment, no?

That research was done. The results weren't what regulators expected (wanted?), so we never got to hear them.

https://youtu.be/xhkBLhw-8pk

Caveat: the interviewer strikes me as quite flakey, but his reactions highlight how grounded Dr Cohen was.

Re: Why is my dryer radioactive?

#134

Post by antognini »

jojobas wrote: post #121
antognini wrote: post #66

Earlier quoted context omitted.

> hobbyist grade detectors (Geiger tubes) are not sensitive to alpha but they are highly sensitive to beta and a little sensitivity to gamma. This was part of the reason why it took so long to discover the cause of Alexander Litvinenko's death by Polonium-210 poisoning. Doctors (and later detectives) had suspected some form of radiation poisoning, but the early tests used Geiger counters and came back negative. But P…

Polonium-210 is a very rare example of near pure alpha-decay chain, radon decay products are short-lived and emit both beta and gamma particles.

Yes, this is why the idea to use Po-210 was a stroke of (evil) genius. Because of its unique decay profile it is extremely hard to detect. The FSB agents who did this could obtain a small but lethal dose of Po-210 in Russia and then carry it across borders dissolved in a vial of water. In that state it is not dangerous, so the agents had little risk to themselves by carrying it. And it is also undetectable by border security, even if they were monitoring for radiation.

Re: Why is my dryer radioactive?

#135

Post by red75prime »

Jun8 wrote: post #42
kzrdude wrote: post #39

Earlier quoted context omitted.

I'll just make a note of a few good ones.. https://physics.stackexchange.com/questions/121830/does-eart... There is no tidal bulge

The tidal bulge one is one my all time favorites, you should absolutely read the answer. tl;dr the simplistic view of two tidal bulges (that started with Newton) is wrong! This is one of those physics simplifications that still gets pushed around. For another example, see speed of light in glass is slower than vacuum.

> For another example, see speed of light in glass is slower than vacuum.

For all practical purposes it's true. You'll get higher delays in fiber optics than in, say, radio-relay links. The details of matter-photon interaction are interesting, of course.

Re: Why is my dryer radioactive?

#136

Post by tjmc »

Interesting that the second answer mentions the enhanced radioactivity of laundry detergeant. One of our smoke detectors briefly went off the other day as I walked under it with a basket of wet clothes straight out of the washing machine. Any chance that's what it was?

Re: Why is my dryer radioactive?

#137

Post by bcbrown »

Jun8 wrote: post #42
kzrdude wrote: post #39

Earlier quoted context omitted.

I'll just make a note of a few good ones.. https://physics.stackexchange.com/questions/121830/does-eart... There is no tidal bulge

The tidal bulge one is one my all time favorites, you should absolutely read the answer. tl;dr the simplistic view of two tidal bulges (that started with Newton) is wrong! This is one of those physics simplifications that still gets pushed around. For another example, see speed of light in glass is slower than vacuum.

> For another example, see speed of light in glass is slower than vacuum.

I'd love for you to explain what you mean by this. Either you're mistaken or I'm about to learn something really interesting. Here's a link a quick search brought me, for reference. Are you talking about something other than refractive index, ratios of c, and prisms? Like a latency metric of some kind? I'm very curious.

https://en.wikipedia.org/wiki/Speed_of_light#:~:text=For%20e....

Re: Why is my dryer radioactive?

#138

Post by misja111 »

antognini wrote: post #134
jojobas wrote: post #121

Earlier quoted context omitted.

Polonium-210 is a very rare example of near pure alpha-decay chain, radon decay products are short-lived and emit both beta and gamma particles.

Yes, this is why the idea to use Po-210 was a stroke of (evil) genius. Because of its unique decay profile it is extremely hard to detect. The FSB agents who did this could obtain a small but lethal dose of Po-210 in Russia and then carry it across borders dissolved in a vial of water. In that state it is not dangerous, so the agents had little risk to themselves by carrying it. And it is also undetectable by border…

Thanks for all the great insights! But why was the Po-210 not dangerous in that vial of water? It seems many people who got in touch with it got ill: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1767288/

Re: Why is my dryer radioactive?

#139

Post by Gare »

misja111 wrote: post #138
antognini wrote: post #134

Earlier quoted context omitted.

Yes, this is why the idea to use Po-210 was a stroke of (evil) genius. Because of its unique decay profile it is extremely hard to detect. The FSB agents who did this could obtain a small but lethal dose of Po-210 in Russia and then carry it across borders dissolved in a vial of water. In that state it is not dangerous, so the agents had little risk to themselves by carrying it. And it is also undetectable by border…

Thanks for all the great insights! But why was the Po-210 not dangerous in that vial of water? It seems many people who got in touch with it got ill: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1767288/

That was after they opened it.

Also, from the article:

> The UK Health Protection Agency, which is advising authorities on technical aspects of the case, characterises the contamination in all 12 cases as “not significant enough to result in any illness in the short term,” while “any increased risk in the long term is likely to be very small.”

Re: Why is my dryer radioactive?

#140

Post by rocqua »

Jun8 wrote: post #42
kzrdude wrote: post #39

Earlier quoted context omitted.

I'll just make a note of a few good ones.. https://physics.stackexchange.com/questions/121830/does-eart... There is no tidal bulge

The tidal bulge one is one my all time favorites, you should absolutely read the answer. tl;dr the simplistic view of two tidal bulges (that started with Newton) is wrong! This is one of those physics simplifications that still gets pushed around. For another example, see speed of light in glass is slower than vacuum.

As a note: the tidal bulge image gives an 'equipotential'. I.e. the water level you would get in equilibrium. That part of tidal bulges is right.

The part that is wrong is that the actual water level is nowhere near equilibrium, because the moon moves. In fact, the water level doesn't even approximate this equilibrium but can (and does!) behave very differently.

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