Radiation? No Fear

[Joe_Trotter (imported)]

I am somewhat less intimidated by “Radiation” than most folks.

As a freshman in college, on one of my first days in Chemistry, I learned something that shocked me.

A classmate told me the story of a Professor in the Engineering department who had a new “Geiger counter” – a Geiger-Muller tube hooked up to an amplifier and speaker – the classic science fiction radiation detector.

The Professor was so excited that he called a fellow professor in the Chemistry department and insisted on demonstrating it. He carried the whole contraption out to his car, drove over to the Chemistry Building, lugged the contraption up to the lab, and plugged it in. Nothing.

He dragged the whole thing back to his own lab to find the problem, set it up, and it worked perfectly.

He took it back to the Chem building, and again, it failed to operate.

After a couple of similar pointless excursions, he tried a new tack. He scrounged up a number of long extension cords, and set up the thing out in the Quad. Much better this time, when he turned it on – he heard the familiar pop and crackle we now know are cosmic rays.

He moved the contraption closer and closer to the Chem building. As he approached the front step, the noise began to increase – more popcorn noises. In the front door, it rattled like hail on a tin roof. Crossing the hallway, the noise rose to a crescendo, then stuttered and stopped at the top of a table in the hallway.

Geiger-Muller tubes operate by cascades of electrons. There is a very high voltage on separated cathode and anode, in a vacuum. One is a metal tube with a vacuum inside, and up through the middle of the tube is a metal bar that forms the other electrodes. The very high voltage means that when a high-speed charged particle passes – an electron, a positron, or proton – it releases a short-term shower of electrons that flow across the gap. That brief shower is the “click” of the Geiger-counter.

One of the limits of the Geiger-counter is that when the particle flow gets above a critical level, a constant current develops across the gap that does not particularly depend on external radiation.

On that tabletop, the particle flow was too high. Literally, when the Engineer had turned it on, on the table, it had been dead silent, because it was overwhelmed. That was unsettling. To test this outlandish conclusion, later that night, they turned out the lights and laid a fluorescent tube on the table. There, in the dark, it dimly glowed, powered by the latent radioactivity in the tabletop.

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And, the chemistry student concluded, I was now sitting on that very table. That was not a very funny joke, but I moved anyway. I later asked my lab instructor, a graduate student, if that was possibly true.

He rolled his eyes and asked me where I heard that rumor.

He also dodged the question, so I asked again. Ok, he admitted, it was true. Horrors. In fact, he said, the whole building we were in was so contaminated that no one should be allowed in it. Turns out that some of the initial research and preliminary refining of Uranium had been done in that building during World War II, for the Manhattan project. A couple of years later the building was closed and remained off limits for years. Eventually, I saw men in HAZMAT suits gutting the place and it was completely rebuilt inside.

So do I think that radiation exposure was a direct cause of my current problems?

Not at all.

Remember, the Geiger-counter constantly clicks, even when no radioactive source is near. We are all constantly bathed in very-low-grade radiation. I expect that my total dose of cosmic radiation over my lifetime far exceeds the amount I received in the few minutes I sat on the table.

Radiation, like everything else dangerous, must be respected, but it too, has its place.

[fhunter]

When I was still at school (8-th or 9-th grade, can't remember exactly) while searching for something interesting at school physics lab I found a box with symbol of radiation danger. Opened it and found small Wilson chamber and documentation. It said - "contains plutonium, isotope ... - 10mg". The most interesting of all this was that teacher was as surprised as was I, or even more surprised.

So - you can find sources of radioactivity in places, where you don't expect finding them.

[Kangan (imported)]

There are other forms of ionizing radiation. When I was a boy, the vogue in a shoe store (circa 1948 -1950) was the fluourscope machine to check the fit of your shoes. I can remember standing on the machine's platform and looking into the viewing scope while a beam of xrays shot upwards through my feet and into my gonads. The machines were later banned.

The Nazi's used a similar device in experiments for sterilization.

I have a small bald patch near the base of my scrotum -- did the radiation from the shoe machine do this?

[Uncle Flo (imported)]

I have a small bald patch near the base of my scrotum -- did the radiation from the shoe machine do this?

No, the bald spot is from rubbing it too much when you got a little older! --FLO--

[coinflipper_21 (imported)]

When I was taking physics it was quoted that each of us is bombarded by 16 heavy nuclei every second from cosmic radiation. Nothing much happens because of this since the atoms in our bodies have astronomically large amounts of empty space in them, however, every once in a great while, one of these atomic bullets from space hits the nucleus of an atom in the vitreous humor in your eyeball and you will actually see the resulting flash. Scary, what?

The real interesting thing is that we are bathed in an increasing level of microwave radiation from cell phones, communications satellites, Wi-Fi and all the other myriad wireless connections that we seem to have become addicted to. Is it damaging or simply harmless? No one knows but if you're still around in another 50 years, or so, you probably will.

Then there's the fact that the North Magnetic Pole has moved several hundred miles toward Siberia in the last century from the relatively fixed point that in had been in Canada for the previous 500 years. Are we due for another pole flip? Does the Earth's magnetosphere shut down for an indeterminate time when a pole flip occurs? Will we need SPF 2500 sunscreen?

See, there are lots of things involving radiation that you can worry about if you want to.

[devi (imported)]

Somebody I know who was into gold prospecting (convinced that he was going to get rich) gave me a heavy rock telling me that the reason it was so heavy was because it had gold in it and that if I found a way to pulverize it and extract the gold from it I might have a spoon full of gold or something. (Gold is a heavy metal of sorts.) But there ARE a few other metals that are heavier than gold and knowing the region that I'm in I had another idea what was actually in that rock. So I went ahead and analyzed it. No aurium. No argentium. Yes uranium. I probably drink a slight amount of it in my drinking water and am not too concerned. --One of those trace minerals that the body might need afterall.