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  1. #16
    Registered user. roughbarked's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: Kevin W.)

    Trichlorethylene.. nasty

  2. #17
    Registered user. Kevin W.'s Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: roughbarked)

    Yes it is very nasty, i was exposed to it a fair bit back in the 1980,s, no mask, no gloves, bare hands no ventilation.
    One clock at a time. Kevin West
    http://www.global-horology.com/GHMB/

  3. #18
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    Default Re: Radium-painted clock dials a radiation concern? (By: Kevin W.)

    I have a coffee table with lovely red granite. I put my pocket counter
    on it and it is 3 time background.
    I set the counter on one of the large granite chunks in Yosemite and it
    is 2 times background. Make you think the next time you sit on a rock.
    As was mentioned, potassium 40, left over from whatever super nova
    created the stuff we are made of, is in us all the time.
    One has to realize that we've evolved in a constant rain of radiation.
    Our bodies are designed to tolerate some levels and repair it self. Still
    it isn't 100%. Cancer still happens.
    Then, we are lucky to be here, without some level of things like radiation
    we wouldn't even be here. Evolution requires mutations.
    I made a cloud chamber for the kids at school. They were surprised that
    The little tracks seen were also whizzing through them as well as my
    cloud chamber.
    Tinker Dwight

  4. #19
    Registered user. Kevin W.'s Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: Tinker Dwight)

    Its a very interesting subject. I never knew there was that much radiation in flying.
    One clock at a time. Kevin West
    http://www.global-horology.com/GHMB/

  5. #20
    Registered user. roughbarked's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: Kevin W.)

    I got into trouble for using the phrase; mostly deteriorated, earlier.

    When you look at half lives, quite a lot is lost in the first few half lives.

  6. #21

    Default Re: Radium-painted clock dials a radiation concern? (By: Kevin W.)

    Quote Originally Posted by Kevin W. View Post
    Did you read the link, more than soil was mentioned. Its not something i ever lost sleep over. its all around us, radiation.
    It's cumulative though, so it does all add up.

    However cosmic rays account for around 10,000 particles per square metre per second so that gives you a base level. Of course those are going to just go straight through you in the main, you are basically made up of a lot of empty space anyway which helps.
    Nick, lots to learn, late starter.

  7. #22

    Default Re: Radium-painted clock dials a radiation concern? (By: roughbarked)

    Quote Originally Posted by roughbarked View Post
    I got into trouble for using the phrase; mostly deteriorated, earlier.

    When you look at half lives, quite a lot is lost in the first few half lives.

    The whole point of half lives is that half is lost in each but it is half of what is remaining hence the exponential curve.

    The isotope of Radium here has a half life of around 1600 years, Radon around a minute.

    - - - Updated - - -

    Quote Originally Posted by Tinker Dwight View Post
    I have a coffee table with lovely red granite. I put my pocket counter
    on it and it is 3 time background.
    I set the counter on one of the large granite chunks in Yosemite and it
    is 2 times background. Make you think the next time you sit on a rock.
    As was mentioned, potassium 40, left over from whatever super nova
    created the stuff we are made of, is in us all the time.
    One has to realize that we've evolved in a constant rain of radiation.
    Our bodies are designed to tolerate some levels and repair it self. Still
    it isn't 100%. Cancer still happens.
    Then, we are lucky to be here, without some level of things like radiation
    we wouldn't even be here. Evolution requires mutations.
    I made a cloud chamber for the kids at school. They were surprised that
    The little tracks seen were also whizzing through them as well as my
    cloud chamber.
    Tinker Dwight
    I made onehere too because it was a real wow for me when I was at school. We have no access to dry ice so I used a peltier sandwich and a computer chip cooler.
    Nick, lots to learn, late starter.

  8. #23
    Registered user. stewey's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: novicetimekeeper)

    I have to ask, knowing really nothing about radio-active materials, if I come across a watch or a clock dial which 'glows in the dark' how can I tell if it's radium or just some type of luminous paint?

  9. #24

    Default Re: Radium-painted clock dials a radiation concern? (By: stewey)

    put it in a dark place for a few hours, if it still glows as bright then it suggests it is producing the light itself rather than reacting to light shone on it. That's the difference. If, however, it is first or second world war period it may no longer be bright at all but will still be just as active.
    Nick, lots to learn, late starter.

  10. #25
    Registered user. stewey's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: novicetimekeeper)

    Thanks, novicetimekeeper.

  11. #26
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    Default Re: Radium-painted clock dials a radiation concern? (By: novicetimekeeper)

    At a Chinese knick-knack store, Youqing negotiated a price and bought a heavy 5-inch round sphere on fake wood pedestal. It glows!
    The store owner claims it is a natural rock. Aiming the cellphone flashlight on it, the yellowish green spot lasted a number of minutes.

    I placed it in clothing in the bottom drawer to be in total darkness. After a few days, at 4 a.m. while my eyes were adjusted to the dark, I opened the drawer and unwrapped the sphere. It wastill slightly glowing!

    We plan to take it to the fire station which has a Gieger counter as part of their hazmat monitoring equipment.
    Confucius say: "Grandfather clock Wall Clock without wall."

  12. #27
    Registered user. Kevin W.'s Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: Robert Gift)

    Robert i would think your rock contains phosphur as that will glow in the dark and is a natural thing, here is a link to pebbles that glow in the dark.
    https://www.alibaba.com/showroom/nat...ing-stone.html
    One clock at a time. Kevin West
    http://www.global-horology.com/GHMB/

  13. #28
    Registered user. stewey's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: Kevin W.)

    I wonder if the other reindeer are aware of Rudolph's hazardously emitting nose?

  14. #29
    Registered user. THTanner's Avatar
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    Default Re: Radium-painted clock dials a radiation concern? (By: novicetimekeeper)

    There are also Tritium dials now being produced. These are neither luminous paint nor radium and should glow the same regardless of being exposed to light. Tritium is also radio active with a 1/2 life of about 12 years but is harmless unless you swallow or inhale it.

    Quote Originally Posted by novicetimekeeper View Post
    put it in a dark place for a few hours, if it still glows as bright then it suggests it is producing the light itself rather than reacting to light shone on it. That's the difference. If, however, it is first or second world war period it may no longer be bright at all but will still be just as active.
    If you are not fired with enthusiasm, you will be fired with enthusiasm. Vince Lombardi

  15. #30

    Default Re: Radium-painted clock dials a radiation concern? (By: THTanner)

    Yes, I'm aware of those, which is why I worded it as I did.
    Nick, lots to learn, late starter.

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