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  1. #41
    Uncle Goose's Avatar
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    LOL, all those people who are worried about radiation of thorium show that they don't have the slightest clue how radiation works. Take a geiger counter and measure the inside of your house, then measure the lens, It might not even be detectable trough the background radiation you receive every single moment of your life. Also, the particles it emits are Alpha and Beta particles, while Beta particles are a little more powerful they cannot go trough things like thick lens glass, nor can the alpha's. Both particles are only dangerous when they float freely in the air as dust.

    Keep in mind that people can have far more dangerous substances in their homes. Remember those old vintage wall clocks that glow in the dark?? well if they are old enough (like WWII area or just beyond that) they most likely contain Radium, and that dear people is a real Gamma emitter!! Far more powerful and dangerous then Thorium used in lenses. I have 2 tabs (which they used to place above the light switches in the 1960's to see the switches in the dark) filled with Radium and while the emissions don't go very far (I use them to test Geiger counters that are part of my NBC collection) I don't want that to float around in the form of dust (the Radium in the tabs I have are safely sealed in Plexiglass). The most dangerous part of radioactivity is when it's released in the form of dust, then it can get everywhere, when it's in the glass it can go nowhere.
    Sure, I could give you a boring explanation who I really am but I rather let the Origami do the talking.

  2. #42

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    "LOL, all those people who are worried about radiation of thorium show that they don't have the slightest clue how radiation works. "

    And I suppose your credentials are degrees in Physics, Nuclear Engineering or are we reading the comments of a degreed Health Physicist?
    Other than those three disciplines I would suggest that individuals refrain from Posting what they 'think' and only what they 'know' to be fact concerning isotopic emmiters, the physical effects and biological effects.
    I commented once but just don't have the time nor inclination to address all the mis-statements.-Dick

  3. #43
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    "Ever been to Utah? Ra-di-a-tion. Yes, indeed. You hear the most outrageous lies about it. Half-baked goggle-box do-gooders telling everybody it's bad for you. Pernicious nonsense! Everybody could stand a hundred chest x-rays a year. They ought to have them, too. When they canceled the project it almost did me in. One day my mind was full to bursting. The next day - nothing. Swept away. But I'll show them!"

  4. #44
    Uncle Goose's Avatar
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    Quote Originally Posted by budrichard View Post
    "LOL, all those people who are worried about radiation of thorium show that they don't have the slightest clue how radiation works. "

    And I suppose your credentials are degrees in Physics, Nuclear Engineering or are we reading the comments of a degreed Health Physicist?
    Other than those three disciplines I would suggest that individuals refrain from Posting what they 'think' and only what they 'know' to be fact concerning isotopic emmiters, the physical effects and biological effects.
    I commented once but just don't have the time nor inclination to address all the mis-statements.-Dick
    At least I did some serious research instead of letting myself make scared by the media and others the don't know squat about it. Most people are like sheep, they just take in whatever they see from the media, I on the other hand do a lot of reading and even inform myself with people who actually work with radioactive products. And what exactly was wrong with my post to begin with?? did it contain any lies?? NO IT DIDN'T! Thorium breaks down in the Alpha and Beta spectrum, not the Gamma or X-rays. Radium does emit Gamma rays, so that's not wrong either. The amount in those lenses are small and they are encapsulated in the glass, so unless you break the glass there is nothing to worry about. Of course radioactive compounds are not toys but in the Post Chernobyl era people are way too scared because the media pictured some grotesque misconceptions about nuclear radiation.
    Sure, I could give you a boring explanation who I really am but I rather let the Origami do the talking.

  5. #45

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    Quote Originally Posted by budrichard View Post
    The check function is purely electronic and verifies if the meter responds to a current. Whether the GM tube is still functional and will generate a current is anyones guess without an actual radioactive source emmitting gamma rays which is what most of these GM counters were designed to detect.
    It's not a "check function" that I'm refering to, but rather a check source. The check source, is a small sealed radioactive substance stuck on the side of the detector. The nuclear physics professor I bought this from told me what the substance was, but now I forget.... actinium maybe.

  6. #46

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    "One day my mind was full to bursting. The next day - nothing. Swept away. But I'll show them!

    From one of my all time favorite movies!!!
    "If you look at a thing nine hundred and ninety-nine times, you are perfectly safe; if you look at it the thousandth time, you are in frightful danger of seeing it for the first time." G.K.Chesterton

  7. #47

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    Quote Originally Posted by One_DaveT View Post
    It's not a "check function" that I'm refering to, but rather a check source. The check source, is a small sealed radioactive substance stuck on the side of the detector. The nuclear physics professor I bought this from told me what the substance was, but now I forget.... actinium maybe.
    If a radioactive isotope. it has a half life i.e. after a certain amount of time only one half will be left to disintegrate and provide readiation to check your GM tube. Therefore you need to know the isotope and half life to determine if the source is still effective in checking your GM. In short, just having a GM counter without the proper documentation and/or training, you don't really know if your detecting anything.-Dick

    "At least I did some serious research instead of letting myself make scared by the media and others the don't know squat about it. Most people are like sheep, they just take in whatever they see from the media, I on the other hand do a lot of reading and even inform myself with people who actually work with radioactive products. And what exactly was wrong with my post to begin with?? did it contain any lies?? NO IT DIDN'T! Thorium breaks down in the Alpha and Beta spectrum, not the Gamma or X-rays. Radium does emit Gamma rays, so that's not wrong either. The amount in those lenses are small and they are encapsulated in the glass, so unless you break the glass there is nothing to worry about. Of course radioactive compounds are not toys but in the Post Chernobyl era people are way too scared because the media pictured some grotesque misconceptions about nuclear radiation. "

    I never said anything was wrong with your Post. I was merely trying to ascertain your credentials. Your statements actually lead me to believe you had none in this area. Now that may be good and that may be bad. It's up to you to make that determination but to make the statement "in the Post Chernobyl era people are way too scared because the media pictured some grotesque misconceptions about nuclear radiation" shows an incomplete understanding about the subject and the dangers. My last statement still stands:
    "Other than those three disciplines I would suggest that individuals refrain from Posting what they 'think' and only what they 'know' to be fact concerning isotopic emmiters, the physical effects and biological effects.
    I commented once but just don't have the time nor inclination to address all the mis-statements"
    -Dick

  8. #48

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    Quote Originally Posted by budrichard View Post
    If a radioactive isotope. it has a half life i.e. after a certain amount of time only one half will be left to disintegrate and provide readiation to check your GM tube. Therefore you need to know the isotope and half life to determine if the source is still effective in checking your GM. In short, just having a GM counter without the proper documentation and/or training, you don't really know if your detecting anything.-Dick
    -Dick
    Yes, this is all pretty common knowledge for anyone with a little interest. No, you do not need to know the isotope and half life for a check source. I think you have an inverted view of how to use a check source. If as you imply, a radioactive isotope with a very short half life was used as standard check source , and disentragated long before my test, the result would be that the check source test would not register. This opens up the possibility of a false-negative, i.e. a dead detector that's not actually dead. However, there is no room for a false-positive, as you are concerned, i.e. a working detector that is actually dead. What can not be done with an unknown check source, is to callibrate the actual reading.

    I'm not really clear on what's driving this bad detector discussion. As I mentioned earlier, regarding the 1960's quip, I don't believe it to be the case. My detector was last callibrated in 1996, and it's a model that can be bought on-line today. Do you have one of the lenses that I have listed and believe it to be radioactive?

  9. #49

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    "Do you have one of the lenses that I have listed and believe it to be radioactive?"

    Nope, but I do have Trinitite, sand fused by the first Atomic Bomb blast and graphite from Chicago Pile Number One(CP1), the first Reactor.
    I don't spend my time worrying about these or lenses as there is real stuff to worry about.-Dick

  10. #50
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    Thorium-232 has a half-life of 14.05 billion years, which---though it's about the age of the universe---is still apparently shorter than the half-life of this tedious thread.

    @FilmOnly, when you fixate on minuscule risks that have virtually no chance of harming you, while you daily engage (I presume) in other activites that pose orders-of-magnitude higher risks to you without giving them a thought (you DO drive a car, no?), then, sorry, yes, that IS irrational. behavior.

    Now, you are perfectly within your rights to engage in irrational behavior that doesn't harm others; but don't call it something it's not, and expect to go unchallenged.

    Here expireth my half-life. I'm out.
    Last edited by MikeSeb; 11-29-2009 at 06:01 PM. Click to view previous post history.
    Michael Sebastian
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