I went to pick up a routine prescription at Target Pharmacy yesterday and three people in line were demanding the pharmacist order “anti-radiation pills” for them. Two people wanted to take the pills now, the third guy wanted to resell them on Ebay for a hundred dollars. The pharmacist was trying to calm them and explain that radiation was not going to effect them over here in New England.
We spent an entire week (8th grade) going over radioactivity, how isotopes, Sr-90, I-131, etc maintain the same chemical properties as non-radioactive isotopes
and how they can be absorbed into body systems. We discussed the effects of ionizing radiation on living tissue. Hopefully, my 8th graders are now more informed
then the dolts in Target.
The funny thing is, we live about 25-30 miles from an aging nuclear plant that sits on a fault line (rarely active, but a fault line nonetheless.) It would be good idea to have the pills in the medicine cabinet, especially for children, in the unlikely event of a local disaster.
So people taking the pills because of a plant in JAPAN, and not being aware of their own plant and its conditions, is rather odd.
Blaming people for misunderstanding and still acting upon news about fission reactor disaster, matter-to-energy conversion, meltdown, radioactive particles, isotopes, half-life, and etc. These topics are strange and foreign to most people, expect them to misunderstand, be helpful by helping them to understand… iodine pills are bad, except as a last resort measure.
BTW, does anyone know how these rods are handled safely in the first place? How are they handled during manufacturing?
Good link Doug, very informative online.itp.ucsb.edu video. The video said it would take a few inches of lead to stop β-particles, and that electronics can’t be used. I can’t imagine a modern robot without electronic controls, regardless of lots of hydraulics.
BTW, does anyone know how these rods are handled safely in the first place? How are they handled during manufacturing?
Uranium isotopes are almost pure alpha emitters (very little to no penetrating power), a little gamma to be sure, so the rods can be handled quite safely during manufacture and before they are put into a reactor. The U-235 is a fissile isotope so when bombarded with neutrons it will split, and undergo neutron capture, into daughter elements (Sr-90, I-131, Pu-237, etc.) that are much more radioactive, being both beta and gamma emitters, both of which are ionizing, penetrating radiations.
In a nutshell, the waste products of fission are the dangerous ones.
Good link Doug, very informative online.itp.ucsb.edu video. The video said it would take a few inches of lead to stop β-particles, and that electronics can’t be used. I can’t imagine a modern robot without electronic controls, regardless of lots of hydraulics.
Yeah, it’s the best intro I’ve seen to all the issues. There’s a lot there that isn’t specific to Fukushima. I’d also been wondering about robots, and that info was very sobering. I’ve no idea how sophisticated an all-hydraulic robot could be; certainly it couldn’t have onboard AI and probably it’d have to have a cable link, in which case it couldn’t go very far or in heavily destroyed terrain. (The cable might snag).
I’d also been wondering about robots, and that info was very sobering. I’ve no idea how sophisticated an all-hydraulic robot could be; certainly it couldn’t have onboard AI and probably it’d have to have a cable link…
You’re probably right, Doug, he probably meant a device with arms, wheels, and a long cable, snags and all, maybe fiberoptic cable for vision. But if they did want a sophisticated decision making robot, then I think that a few inches of lead shielding for electronic controls would be much lighter and cheaper than a mechanical robot. I suppose that the radiation would induce currents in the electrical control cable, but with the α and γ frequencies being so high I imagine that a radio signal could penetrate through to control the robot. For the mechanical controls of a robot, imagine something at least as complex as a mechanical cash register, a carburator, a combination lock, etc.
Thanks TeachScience. Doug’s video touched on some of that, but said that many of the fission products decayed quickly (gamma particles being very energetic emissions), so wouldn’t that mean that the spent fuel rods have become safe enough quickly after they reach the pool? It seems like the pool of spent rods is being reported as one ef the big dangers?
And the fission products are “much more radioactive”, you say? Huh? So then the energy increases as there are more fission products, an increase in energy? I must be misunderstanding, that sounds backwards, correct me please.
Can I think of half-life and the amount of energy being radiated inversly related and proportional?
I posted a CNN link in Good luck Pacific coast explaining the reactor’s problems journalistically rather than scientifically, if anyone here wants it.
Thanks TeachScience. Doug’s video touched on some of that, but said that many of the fission products decayed quickly (gamma particles being very energetic emissions), so wouldn’t that mean that the spent fuel rods have become safe enough quickly after they reach the pool? It seems like the pool of spent rods is being reported as one ef the big dangers?
Most of the fission products decay quickly, but not all. There’s a Cesium isotope that has a half-life of 50 years; that’s one of the dangerous ones and, from what I understand, the primary culprit behind the persistent radiation cloud after Chernobyl.
And the fission products are “much more radioactive”, you say? Huh? So then the energy increases as there are more fission products, an increase in energy? I must be misunderstanding, that sounds backwards, correct me please.
Can I think of half-life and the amount of energy being radiated inversly related and proportional?
Only if the radiation type is of the same type. And only if the decay product is stable, not also radioactive.
I pretty much agree with Trombone here, except I find the half live of Cesium-137 (which is the one he is referring to) to be 30 years. Many people are more afraid of materials that have half lives of millions of years but products with short half lives are, in general, the most dangerous. There is an excellent fact sheet on cesium HERE from the Nat’l. Argonne Labs.
Thanks TeachScience. Doug’s video touched on some of that, but said that many of the fission products decayed quickly (gamma particles being very energetic emissions), so wouldn’t that mean that the spent fuel rods have become safe enough quickly after they reach the pool? It seems like the pool of spent rods is being reported as one ef the big dangers?
Most of the fission products decay quickly, but not all. There’s a Cesium isotope that has a half-life of 50 years; that’s one of the dangerous ones and, from what I understand, the primary culprit behind the persistent radiation cloud after Chernobyl.
And the fission products are “much more radioactive”, you say? Huh? So then the energy increases as there are more fission products, an increase in energy? I must be misunderstanding, that sounds backwards, correct me please.
Can I think of half-life and the amount of energy being radiated inversly related and proportional?
Only if the radiation type is of the same type. And only if the decay product is stable, not also radioactive.
In terms of radiation an health issues, simply talking about energy released isn’t quite the way to go, I think.
The radioactive isotopes are radioactive because their nuclei are inherently unstable, this typically arises from imbalances in the proton/neutron ratio in the nucleus. The more unstable they are the shorter their half-lives and the more radioactive, all things being equal. U-238 has a half-life of 4.46 billion years and is really not all that dangerous.
Some fission products have extremely long half-lives but emit very little radiation at any given time, so they are not very dangerous. Other fission products emit huge amounts of radiation but exist for such a short period of time that they are not dangerous. The ones in between these extremes are the ones to worry about. If you look at a graph of half-life v. % radioactive element remaining, you’ll see that about ten half-lives must pass before the parent element has decayed to near zero levels. The end element in a decay chain is always stable e. g. Pb-206 as the end for U-238. Nuclear stability is the goal for radioactive decay.
Heyya, looks like we have a few who know some about this. Interesting posts. Let me try a few questions:
It is being reported that Fukushima radiation is now being detected in the fair state of Colorado.
What is being detect?... or better what is emitting the radiation that is being detected.
Are these tiny particles?
Which kind of radiation is that?
How does that compare to the radiation being given off by the mountains up here anyways?
Thanks for the tip on kitp.ucsb.edu, will have to check it out when I can.
Heyya, looks like we have a few who know some about this. Interesting posts. Let me try a few questions:
It is being reported that Fukushima radiation is now being detected in the fair state of Colorado.
What is being detect?... or better what is emitting the radiation that is being detected.
Are these tiny particles?
Which kind of radiation is that?
How does that compare to the radiation being given off by the mountains up here anyways?
Thanks for the tip on kitp.ucsb.edu, will have to check it out when I can.
1.) iodine-131.
2.) yes
3.) beta and gamma
4.) The background radiation in the mountains is much greater than that from the iodine-131
Are you folks familiar with the International Atomic Energy Agency website? http://www.iaea.org
It’s interesting reading their news updates - nice dry science reporting the facts.
Looks like this incident isn’t the end of the world…
but boy oh boy is it first class major league SNAFU ! (Situation Normal All F#@7ed Up)
Accumulated contaminated water was found in trenches located close to the turbine buildings of Units 1 to 3.
Dose rates at the surface of this water were 0.4 millisieverts/hour for Unit 1 and over 1 000 millisieverts/hour for Unit 2 as of 18:30 UTC on 26 March.
The Nuclear Safety Commission of Japan suggests that higher activity in the water discovered in the Unit 2 turbine building is supposed to be caused by the water, which has been in contact with molten fuel rods for a time and directly released into the turbine building via some, as yet unidentified path.
An investigation is underway as to how the water accumulated in the trenches. Measurements could not be carried out at Unit 3 because of the presence of debris.
In the nuclear meltdown saga in Japan, here are some of the latest developments from the BBC
Problems with the removal and storage of contaminated water:
So, according to Tony Roulstone, from Cambridge University’s department of engineering, the substantial quantities of contaminated water will have to be pumped away and “immobilised” - perhaps by locking it up in concrete, which would then be stored.
If engineers cannot identify the precise source of the contaminated water and seal it off, they will have to build a steel or concrete “surrounder” to catch it. The water would then be piped away to another site for immobilisation.
Richard Lahey, head of safety research for this type of reactor at General Electric, which installed the reactors at Fukushima in the 1970s, says workers at the site appear to have lost the race to save the crippled No. 2 reactor.
The Guardian newspaper quotes him as saying he believes the reactor core has melted through the bottom of the pressure vessel and at least some of it is down on the concrete floor beneath.
This would mean in simple terms the accident is no longer a matter of melting fuel rods, but of meltdown.
It will take years to cool everything:
Hiroto Sakashita, a nuclear reactor thermal hydraulics professor at Hokkaido University, says the other reactors and cooling ponds will take years to cool.
“They will just have to keep on pouring and pouring but contaminated water will keep leaking out,” he told The New York Times.
The video said it would take a few inches of lead to stop β-particles, and that electronics can’t be used. I can’t imagine a modern robot without electronic controls, regardless of lots of hydraulics.
