Radiation issues - Chernobyl

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Richard Hull
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Radiation issues - Chernobyl

Post by Richard Hull » Wed Nov 10, 2010 4:12 pm

While we often are concerned about radiation in our experiments and protect ourself accordingly, take a look at this NOVA broadcast. It is frightening. When you send people into 200r/hr fields, "that" is real radiation. The "elephants foot" in part 2 at 10,000r/hour is incredible.

The Russian physicist's delight at the lovely and magnificent melted structures in their journies throughout the guts of the core area is interesting and shows a remarkable scientific curiousity and detachment from the horrors that allows them to continue with the effort to study the accident's aftermath and future.

http://www.youtube.com/watch?v=0KeSXMTzt6M

Note: This is broken into about six -10 minute segments. It is worth seeing. The next time you get a 5mr/hr reading off a piece of hot U ore and are a bit fearful, you can realize how truly minimal such levels are.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Re: Radiation issues - Chernobyl

Post by lutzhoffman » Wed Nov 10, 2010 8:45 pm

Very Interesting !!!

Thanks for posting; yes you are correct fear is very irrational in nature, especially when dealing with something which is not part of our normal educational system.

Where I live we have folks who are very worried about minute amounts of DU on a military reservation and training area. We are not talking about heavy DU penetrator rounds, they are worried about a few kg at most from some old WW2 spotting rounds, spread out over many square miles. Never mind the fact that the top layer of the earths crust in the same place has over a ton of natural U with all of the daughters.

What I worry about is chemicals; they present up to100 times the statistical cancer risk to the general public of radiation exposure. Yet the same folks who worry about these minute amounts of DU, still microwave their food in plastic containers, and for example cover their lawn with 2,4 D containing weed and feed. Thus they raise the dioxin load of their environment every month, and add a toxic brew of other chemicals, while being paranoid about tiny amounts of DU far away.

Maybe risk assessment and statistics should be part of our educational process? But then again, the chemical lobby may not like that.....

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Re: Radiation issues - Chernobyl

Post by JohnCuthbert » Wed Nov 10, 2010 9:42 pm

"What I worry about is chemicals; they present up to100 times the statistical cancer risk to the general public of radiation exposure."
Don't forget that 100 times roughly zero is still roughly zero.
It's the people who smoke, drink and eat dodgy food while complaining about chemicals that have really missed the point.

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Re: Radiation issues - Chernobyl

Post by derekm » Thu Nov 11, 2010 2:01 pm

you can see a tanker of vinyl chloride or bromine on any day on a motorway or in a railway siding.

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Steven Sesselmann
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Re: Radiation issues - Chernobyl

Post by Steven Sesselmann » Thu Nov 11, 2010 8:14 pm

Just on the subject of radiation and cancer...

What are the chances of firing a shotgun (gamma ray) at a DNA molecule and accidentally creating a self replicating organism?

I imagine it would be almost impossible, in all but a statistically insignificant case.

Recently there is much more evidence that cancers are spread by viruses, which makes a lot more sense. Virtuses carry specific code that can enter cells and corrupt the program.

No doubt there are stochastic effects that one can suffer from prolonged radiation, but I imagine this is is a result of the weakening of ones immune system, due to the cell death of fast replicating cells in the body.

My guess is that cancer viruses are around us all the time, and that our bodies when healthy, do a pretty good job of mopping them up, but when our immune systems are under stress, such as when exposed to prolonged radiation, the virus gets the upper hand.

Richard, thanks for posting the videos.

Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG

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Re: Radiation issues - Chernobyl

Post by JohnCuthbert » Thu Nov 11, 2010 8:57 pm

"What are the chances of firing a shotgun (gamma ray) at a DNA molecule and accidentally creating a self replicating organism?"
Practically nil, unless you start with a self replicating organism.

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Re: Radiation issues - Chernobyl

Post by Dustin » Fri Nov 12, 2010 6:10 am

Cells are self replicating but not really organisms by them selves.
If such a thing was possible we would probably have seen it.

Like the infectious facial cancers in Tasmanian Devils

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Re: Radiation issues - Chernobyl

Post by UG! » Fri Nov 12, 2010 12:49 pm

With Human cells the first exposure will almost certainly not cause a cancerous cell. Human cells are very good at both repairing DNA damage then self destructing if the repair turns out to be wrong. In order for a cancer to form it is usually the case that the mechanisms for self repair or detection of faulty DNA are damaged. This must be done in a way that produces a viable cell, which must then undergo further mutations to produce something that could be called a cancer cell. This process usually takes about 20 years from the initial exposure, given normal background dose and assuming the pathway above. Most cells would just self-repair DNA, form something that can’t function and promptly die. Massive cell death being the cause of radiation sickness, in its various forms.
Regarding the cancer causing potential of radiation, IIRC a whole body gamma dose of 1Gy (enough to give one a noticeable case of radiation sickness) will increase ones chance of getting cancer by about 5% when you consider our chances are about 33% anyway... it’s not really worth worrying about. Of course that doesn’t take into account ingestion of radioactive material that stays around in your body.

Just my 2p worth of (probably badly remembered) MSc lectures

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Re: Radiation issues - Chernobyl

Post by Richard Hull » Fri Nov 12, 2010 3:18 pm

The gist of the original post was to show that our exposures are minimal in intensity. (1-3 mR/hr), and of very short period as none of us operate for more than a few minutes and then only a couple of times a month for most who are making decent amateur fusion. Of course, most us operate rather remotely within a couple of meters from the fusors and get sub-mR doses.

The Russians stumbling around in the core area are literally clubed with lethal levels from the get go, forcing them to submit to only rather microscopic periods of exposure. Too much junk and twisted metal for most robotic devices to do the work for them.

In their environment, I would be most worried about my eyes. One of the most rad sensitive of organs and one of the most handy to have in good shape.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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