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radiation levals THE FACTS

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Ok so a lot of people in the US are freaking out about the radiation levels from the Fukushima plant reaching Them in the western united states when in reality the radiation is less than that what we already receive from a coal plant.Yea that right COAL!!!

My physics teacher showed use this in class.
should straiten things up.
http://xkcd.com/radiation/
My first thought when I read this chart was Bananas are radioactive LOL :thinking:
 
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No duh? It's still fun to see if people are able to detect anything with their own instrumentation.

And yes, bananas radioactive isotopes of potassium. You could probably detect a banana with a sensitive geiger counter and enough sample time. Salt substitutes that use potassium chloride are also detectable.
 
If you have any uranium glass marbles, they are slightly radioactive as well (beta-decay).
 
lazerman121 said:
Ok so a lot of people in the US are freaking out about the radiation levels from the Fukushima plant reaching Them in the western united states when in reality the radiation is less than that what we already receive from a coal plant.Yea that right COAL!!!

My physics teacher showed use this in class.
should straiten things up.
http://xkcd.com/radiation/
My first thought when I read this chart was Bananas are radioactive LOL :thinking:
Click to expand...

Yes, go back to sleep people, nothing to see here...

Yes a nuke plant usually puts out less radiation than a coal plant of the same capacity. A million tonnes of coal has a lot of nasties in.

But "THE FACTS" are that some of the reactors have melted down, and explosions have caused leaks. Radiation levels have reached 1 Sv/hr near one of the reactors, a fatal dose in a few hours. Fission is still occuring, so I'm hoping these poor guys get the situation under control asap.

Levels in other countries are within safe limits, so dont panic! Yet.

Hopefully most of the contamination will remain on site to be concreted over, and we will make changes to the way we use nuclear power.

We shouldn't write off nuclear power, nothing comes close to its energy density. The OP is correct, nuclear power is the safest and cleanest when its working properly. It seems there were some flaws and oversights in the Daichi plant, and we should reevaluate reactor designs.

There is enough uranium and thorium to provide well over 2000 years of power at current consumption. We just need to harness it in a safer way.
 
As I made clear in my original thread about this "cloud", My normal background count is ~ 10 to 12 C/M (counts or clicks per minute).
After Chernoble, I reached 15 C/M for one period and I covered my head with foil:crackup: -- Right ----

During the problem in Japan, I have not gone over 12 C/M -- No foil needed here in Iowa !!!!!

HMike
 
Why can't they build a large shaft that goes 100 feet into the ground with very thick concrete/led whatever walls. Build the reactor above it and if starts to melt down cut the cord and drop it in. Then bury and cap it off like a big hazard waste container?
 
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^ ehm ..... never heard about chain reactions ? ..... you need to turn it off, before bury it, is this the dangerous part (that what is actually killing all those volunteers in Fukushima, just for give an example).

A meltdown core buried when it's still on and uncontrolled is unpredictable ..... can slowly turn itself down (in a lot of time), can increase the combustion rate and melt anything, can also overcome the critical point and explode (and, trust me, you will be not too much happy, having an a-bomb exploding underground near your place ..... "localized earthquake" give an idea) ..... you can't simply risk to bury it and forgot it, unfortunately ;)
 
They need to tow large pieces of icebergs from the arctic and lift chunks of ice with cranes and lay them on top. They should cool a little faster than just water. Yeah, there is no safe alternative other than to cool the fuel rods. Boron absorbs neutrons which inhibit fission reactions and therefore help to cool the rods. That is if they can get rods out and not have puddles of fuel seeping into the earth.
 
The big problem that they have is that they cannot just throw all the water on the core and then left it reflow in the sea, for not spread contamination ..... and the containment basin have not an infinite capacity ..... and, i can guess, the lifting system for the bars must be broken or totally gone, otherwise it was the first thing to do for stop the reaction (lifting the fuel bars and pushing down the control bars, i mean)

Another "little" problem is that only the boron-10 isotope of boron is useable in the reactors, both as control rods (borosilicate form) and liquid (boric acid) ..... and boron is already a rare element, itself, and only 20% is boron-10 ..... it's not exactly easy to find in big quantities, when you need it (otherwise, i suppose they already have flooded the reactors with it and turned it down).
 
as a side note, I've been reading (and occasionally trolling) a few pro nuke power website blogs. Rather interesting to see how the pro nuclear power crowd sees the situation in japan. There is as much BS in the pro nuke crowd as the anti nuke. There is a lot of information there, however everyone tries to twist the facts to support their own views. Such as people love to point out repeatedly that there is substantial background radiation levels per year, that we already get exposed to. Listing the annual levels which can vary from 2 mSv per year, to 30 mSV per year. With the max US limits for nuclear power plant workers being 50 mSv per year. They then point out what a small percentage the radiation at the front gates of the plant is. around 90 uSv

Of course they "forget" to mention that this is per hour. not per year. So the current annual dosage at the front gate of the fukushima plant is around 788 mSv per year. which is way above still the max japanese limit they instituted of 250 mSv per year.

Currently the risk to other countries is heavily overplayed by the media, but the facts seem to indicate the area of the plant itself and a few km around it will likely end up being abandoned. At least until the longer lasting isotopes decay a bit. Still a severe disaster, but nothing like the chernobyl or kyshtym disasters. It's too localized, with too much of the radioactive isotopes ending up diluting in the ocean rather then on land.

Still, I would hate to be trying to sell fresh fish in japan right now. Too much paranoia out there.

As a side note, on the thorium reactor concept. There are molten salt thorium reactor designs out there. You can't have a bad meltdown (i.e, chernobyl) since the fuel is already liquid. There's a drain plug in the bottom that needs active cooling to stay solid. if cooling is lost, the fuel melts it, and then drains out into subcritical structures below, with a lot of passive cooling potential. Sounds good, (and it's just one type of thorium reactor) the downside is you get different risks instead. Reprocessing accidents (like the kyshtym accident, while not thorium based, it was a processing accident) are more likely, and hot fluorine present and is highly reactive with any type of hydrogen. So exposure to water through some sort of mishap results in the production of hydrogen fluoride gas. (to which just about everything seems to be allergic to) Upsides and downsides. Thorium reactors of all types are not really any better or worse then uranium. They simply carry different risks.


Nuclear power often gets compared in number of accidents vs coal power. Of course these statistics are also typically twisted to make nuclear power look even better. You see most statistics list the number of total coal power deaths, vs the number of nuclear power deaths. Forgetting that the number of nuclear power plants worldwide is small compared to the number of coal power plants. If you have 100 coal power plants for every nuclear power plant, then it goes to figure that you will have 100 deaths for every nuclear power death, all things bring equal. (which they are not, there are other things like coal power has been around much longer then nuclear power, etc) Granted even adjusted for numbers, nuclear power is still safer then coal, but the facts still get twisted, by proponents to make it look more so. Hardly surprising really.
 
StridAst said:
Of course they "forget" to mention that this is per hour. not per year. So the current annual dosage at the front gate of the fukushima plant is around 788 mSv per year. which is way above still the max japanese limit they instituted of 250 mSv per year.
Click to expand...

1. Who hangs around the front gates of a leaking nuclear power plant for a year at a time?

2. Will the levels even stay that high for a year?

3. How does it compare with other health risks?
 
StridAst: Regarding your last paragraph, I last heard that statistic as deaths per terawatt hour, which I think is a pretty reasonable way to compare.
 
Cyparagon said:
1. Who hangs around the front gates of a leaking nuclear power plant for a year at a time?
Click to expand...

lol good point. Though I mentioned the reading at the gate largely due to a lack of up to date and plausible readings from farther away However this reading is way above the levels of contamination that the soviets used to justify abandonment of multiple cities after their two worst disasters. It wouldn't prevent the continued operation of reactors 5 and 6, but you wouldn't want to live nearby if the contamination has spread beyond the front gate much.

2. Will the levels even stay that high for a year?
Click to expand...

No, the short lived isotopes will decay away, and some of the contamination will wash away into the ocean. The levels will drop off sharply for a month or two (once the leaks are fixed) then level off a lot waiting for the much longer halflife of the longer lived isotopes. Will still probably be well above the 250 mSv per year limit though.

3. How does it compare with other health risks?
Click to expand...

Actually that is a subject of much debate. It depends on more variables then you can really consider easily. For instance, iodine radioisotopes are extremely dangerous in low concentrations to infants. The younger you are exposed, the much much greater the risk of thyroid cancer becomes. So for that (short lived) isotope, the risk is much greater. But again, nobody is going to bring their 6 month old baby to hang out at the front gate of a leaking nuclear plant. lol Also granted thyroid cancer is probably the easiest of all cancers to cure. My boss actually had thyroid cancer last year. The cure? um ironically, radioactive iodine....... (after surgery to remove the thyroid completely)

Then you have cesium 137, a long lived isotope that last 30 years, yet it collects in the muscles, which are not prone to cancer so much. while there are a lot of other decay products that are quite bad (strontium 90 comes to mind), the cesium and iodine are the two that seem to be getting the most press info lately. While cesium ingested appears to not be so bad, exposure to the skin might increase the odds of skin cancer.

However to what effect depends on who you listen to. Some people firmly believe in the "no threshold" concept, where all radiation is bad, and statistically increases the odds of cancer at any dose proportionately. Then you have the crowd who believe that there are firm radiation exposure thresholds that levels below are harmless, and levels above are bad. Both sides seem to attempt to statistically prove their views. *shrug* given just how much we poison ourselves with how many nasty things in our environments from a myriad of sources, it's hard to statistically prove anything was caused by radiation, and not some other carcinogen. (read: futile) The exception seems to be iodine radioisotopes since they target exclusively the thyroid, and are easy to single out. But again, it's easily cured for the most part.

So the variables you have are: age of the exposed person. What element you are exposed to, dosage of the exposure, duration of the exposure, and location of the exposure (internal/external) Also there is the density of the exposure. a mSv of exposure spread over your entire body, might not have the same effect as a more localized and concentrated dose. I've seen nothing addressing this anywhere, but it seems logical that the power density in the radiation must have a part to play as well. Also which theory is correct, threshold or no threshold? While I personally believe there must be a threshold somewhere, I've found little non-conflicting data on what this threshold is. And these variables are just the radiation side of the equation, let alone the myriad variables associated with every other health risk we face because of just what we do to ourselves and the planet.... =/

*shrug* Pinning down with online reading just how bad any of this is, seems to be rather hard to do. The absence of concrete data seems to be an indication that it can't be as bad as people make it out to be. However people feel panic and fear about radiation, and while that is an irrational response, it is no less a danger and hazard of radiation for that. The panic will do more damage then the radiation. So until the time that the general public can act responsibly and rationally (read: when hell freezes over), one of the hazards of radiation will continue to be the fear and terror people feel about something they can't see but believe can hurt them.

I would agree that the threat from radiation is probably heavily overstated, but for all that, the numbers still seem to be twisted by both sides, which makes it harder to trust either side.

@moonshadow, that seems to be a *very* reasonable statistic for comparative use. got any links to statistics on it? :D

Ok, I just looked at this epic long babbling post. My apologies to anyone who actually reads it all. I blame too much blood in my caffeine stream. :D time to fix that. (reference above mention of "just what we do to ourselves and the planet)
 
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