Radioactivity and Clock Chimes

The April 30, 1999 Column:

If you were radioactive, would you glow? Who wrote the clock chime tune? Click here for the complete column (http://www.straightdope.com/columns/990430.html).

I wonder if the movie referred to was "The Atomic Kid", starring Mickey Rooney? This topic reminds me of the documentary I saw a while back about people who used to paint watches and clocks (using small brushes) with radium so they would glow in the dark. As I recall, after repeatedly using these brushes, a lot of the painters would form a point on their paint brushes by wetting the bristles in their mouths. Predictably, many of those workers started having health problems. I grew up in Central Kansas and there was a nearby town named Radium that also did this kind of work, I think.

This mention of the Sc-Fi-B-Movie rule that "All Radioactive Things Must Glow" reminds me of the MST3K episode where our friends are watching a scene where an airplane begins to exhibit a green glow, and one of them exclaims, "He's suddenly acquired a cool minty flavour!"

Cecil mentioned "the speed of light in a vacuum." Just thought I'd let everybody know that the term "jiffy" is defined to be the time it takes for light to travel 1 cm in a vacuum. We can thank those goofy scientific knuckleheads behind the Manhattan Project for this one.

If current scientific theory holds, there is an opposite for everything, i.e.: every action has an equal and opposite reaction, mater vs. anti-matter, etc. Following that line of thinking (and assuming you are not currently glowing), in an alternate universe you are able to glow with out the help of radiation. If fact, in that universe you'd be asking if excessive radiation would sop you from glowing.

A "jiffy"? Can anyone verify this story? I checked MEASURE FOR MEASURE by Richard Young and Thomas Glover, which lists 39,000 conversion factors from "aam" to "zuz" and could not find a jiffy. Although "Speed of Light" appears under the section of Physical Constants and Defining Constants.

if glow-in-the-dark watch hands have radium and zinc oxide on them, wouldn't they put out harmful radiation? I always thought that radium was a really dangerous substance. Is it just in sufficiently small amounts to be safe?

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"And I say, 'Look, I have no hands!' but everyone around me says, 'What are hands?'"
-Dune

zinc sulfide I mean, not that I care

Actually, the amount of radiation put out by the glow-in-the-dark watch hands, while real, is pretty insignificant. If you were to collect thousands of watch hands and keep them in your pocket all day long, you might be in trouble. However, the poor people who had to paint the watch hands had lots of problems with radioactivity (increased cancer rates, etc.).

TheDude

From Merriam-Webster's Online Dictionary
http://www.m-w.com/

Main Entry: jif·fy
Pronunciation: 'ji-fE
Function: noun
Inflected Form(s): plural jiffies
Etymology: origin unknown
Date: 1779
: MOMENT, INSTANT <ready in a jiffy>

(Especially note the date: 1779.)

The original watch factory was in Waltham, MA, "Watch City", where I live. The watch painters had much higher rates of mouth cancer than normal, because of "pointing" their brushes in their mouths. The rumoured watch factory building is located -- you guessed it -- across the street from an elementary school.

But getting vaguely back on the subject, what about people who are injected with radioactive compounds for medical imaging purposes? If we painted them with zinc sulfide or another flourescent compound, would they glow?

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". . . and all places are alike to me."
--R. Kipling

[[if glow-in-the-dark watch hands have radium and zinc oxide on them, wouldn't they
put out harmful radiation? I always thought that radium was a really dangerous
substance. Is it just in sufficiently small amounts to be safe?]] -awldune

Radium in small amounts is not dangerous, in fact it is a moderately common trace element in coal. Main problem here is that everyone knows that Curie died of cancer, and she discovered radium...therefore the reasoning goes, radium killed her. Curie might have died from radium radiation, though she also dealt with a lot of other radioactive substances, she did spend a long time refining a large amount of radium in her attempts to isolate it. (I say her even though Pierre Curie was also there, but since he died in an accident, is not germain to this.) But the amount of radium and other radioactive substances she dealt with was far more than the average person would ever come in contact with.

[[Dead is dead, but how long would it take? I know radiation causes cancer and
other lethal mutations of cells. But is there a dose which, as opposed to a
drawn-out death by disease would indeed kill instantly? Or within a really short
period of time?]] -Satan

Yeap, just stand 100 yards from a hydrogen bomb for the instant (Well, close enough to instant.) death. :) I believe that some of the survivors of Hiroshima's / Nagasaki's initial blast died of the radiation burns in the few hours after. The problem here is did they die of radation, or of the wounds caused by the burns. Moot point really, is a painfull way to go.

TheDude, Thanks! I knew I was wrong on the specifics, been too long since I read up on that stuff.

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The drake watches

Actually Cecil you are wrong concerning that eerie blue glow that comes from fuel rods under the water. It is in fact that the water is boronated to absorb radiation. Boronated water is deep blue colored.

Narile,
No problem. The only reason I remember that stuff is because I'm still in school and probably will be forever.
Webb,
Actually, "boronated water", which I'm presuming is water with boron compounds in it, would be totally colorless. It is true that if you burn boron containing compounds, they burn with a bright green glow, but the compounds are all colorless under normal conditions.
Questioning the authority of Cecil!? How presumptuous.

TheDude

[[But getting vaguely back on the subject, what about people who are injected with
radioactive compounds for medical imaging purposes? If we painted them with zinc
sulfide or another flourescent compound, would they glow?]] -KatByHerself

Nope. Here one is dealing with the fact that there are three 'types' of radioactive decay. Alpha, Beta, and Gamma particles are given off by radioactive substances, each type of particle has certain properties if you will. I am not a physicist, so my memory might be off here. Alpha particles are nonionising/penitrating, which means they go far, but don't make other objects radioactive. For some reason, I seem to remember Alpha particles are electrons, but I am probably wrong here. Beta particles are ionising/nonpenitrating which means they don't go far ,but have a chance to make something radioactive (They can be stopped by a piece of paper.) I can't recall what a Beta particle is though. Gamma particles are ionising/penitrating, which means they go far, and can make things radioactive. Gamma particles are hydrogen atoms moving very fast if I remember right. The dyes used by medicine for visualizing are usually primarily radioactive in the alpha style. Again, physics class was a few years ago, and I don't have my books here at work (Well, I do, but only the ones on circuit theory and programming. :) ) So I might have some of the specifics wrong, for one thing I think there might be a mistake in Gamma, since Gamma radiation in used in sterilization of food.

Narile has the basic idea correct, but some of the specifics are mixed up. Alpha particles are helium nuclei (2 protons, 2 neutrons) that are ejected from the nucleus. Because they are big and heavy, they are non-penetrating (these are the ones that are stopped by a piece of paper), but potentially ionizing (which does not mean that they can make other things radioactive, but merely means that they can strip electrons off of other molecules to make reactive ions.

Beta particles are electrons that have been ejected from the nucleus (yes, I know there are no electrons in the nucleus; a neutron is converted to a proton in the process), and because they are about 4000 times lighter than alpha particles, they are more penetrating.

Gamma rays are high energy photons that are ejected from the atom. These photons have no mass, and will therefore keep going until absorbed by something. Whatever it is that does the absorption then absorbs a lot of energy and can use that energy to react in some way.

According to my handy periodic table, radium decays by the emission of alpha and gamma radiation. My guess is that it is the gamma radiation that is responsible for the glowing. The high energy gamma rays are absorbed by the zinc sulfide, which then decays by emission of a photon of visible light.

The Dude

[i]If you were to tarry near a spent fuel canister bathed in Cerenkov radiation, you'd receive a lethal dose in seconds. You still wouldn't glow; you'd just be dead.[i]



Dead is dead, but how long would it take? I know radiation causes cancer and other lethal mutations of cells. But is there a dose which, as opposed to a drawn-out death by disease would indeed kill instantly? Or within a really short period of time?




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Brian O'Neill
CMC International Records
http://www.cmcinternational.com

ICQ# 35294890
AIM Scrabble1

If you were to tarry near a spent fuel canister bathed in Cerenkov radiation, you'd receive a lethal dose in seconds. You still wouldn't glow; you'd just be dead.



Dead is dead, but how long would it take? I know radiation causes cancer and other lethal mutations of cells. But is there a dose which, as opposed to a drawn-out death by disease would indeed kill instantly? Or within a really short period of time?




------------------
Brian O'Neill
CMC International Records
http://www.cmcinternational.com

ICQ# 35294890
AIM Scrabble1

At a certain commercial nuclear facility "tribal knowledge" stated that the blue glow was due to Bremsstrahlung effect, as opposed to Cerenkov radiation. I do not question Cecil's explanation, as I sometimes found that there was a prevalence of tribal knowledge amongst those that had no vested interest in accuracy. However, it was definitely not due to blue boron.

OK in order to understand the short term vs. long term effects of ionizing radiation, a little lesson on terminology is in order. So, here goes.

Sometimes you here terms like dose or dose rate, REM, RAD, or Roentgens. Let's start with RAD. A RAD is roughly the amount of any type of radiation equivalent to 100 ergs in 1 cubic centimeter of dry air. A Roentgen is 1 RAD of gamma radiation. A REM (Roentgen equivalent man) is that amount of any type of radiation which causes the amount of BIOLOGICAL damage equivalent to depositing 100 ergs of gamma radiation in 1 gram of soft body tissue. RAD and REM can be equated by using a "quality factor". For gammas the Q factor is 1. So, 100 RAD is equal to 100 REM. For alphas the Q factor is 20. So 100 RAD of alpha radiation is equivalent to 2000 REM.
Dose is the amount of total radiation received in REM. Dose rate of course is the rate at which you received the dose. An average chest X-ray will give you about 0.1 rem (100 mrem), watching T.V. for a year will net you about 1 mrem, and an average day at the beach (in Hawaii) will give you around 20 mrem.
Long term cancer risks goes as follows: In any random sample of 100,000 people, 1600 will die of cancer. If you expose those 100,000 people to 1 rem of radiation (instantaneous) then 1601 people will die of cancer.
Short term effects are dependant on how much. of course. Up to 25 REM, no effect. 25 -50 rem, small changes in the blood, nausea. 50-100, vomiting and blood dammage leading to various problems. 100-500 rem, all the things you think about radiation, hair loss, teeth loss, vomiting, etc. 50% will die. over 500 is almost certain death. over 1000 rem is instantaneous death.

Anyway I hope that helps.

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"If you stick your finger in a pie, whatever is in the pie will be on your finger, and whatever is on your finger will be in the pie...unless you wear a rubber glove"----some demented old lady

All right, so it's taken me a while to get back to you. My question was a trick question, actually, since I already know the answer -- I was just hoping for a bit more detail, like the best substances to use next time I go in for X-Rays so I can really play havoc with the techs. In case you're wondering, I *am* a physicist, and I *have* worked with medical imaging. We were building a portable gamma camera, and testing it on people walking out of Dr's offices after being imaged. Turned out we could see their fingers with our neat little camera -- which ONLY imaged high-energy photons (I wrote the software which filtered out lower energies, and our machine didn't register betas or alphas) So technically, if you injected someone with a nonlethal dosage of a gamma-emitting radioactive substance, and painted them with a substance which fluoresced when exposed to that wavelength, they WOULD glow. You wouldn't be able to perceive the glow unless you were in a cave at midnight during the dark of the moon, and possibly not even then, but tiny amounts of visible light would be emitted.

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". . . and all places are alike to me."
--R. Kipling

WELLLL...we like ourselves don't we Kat?

Just out of curiosity; did you image people who were not recently exposed to see if they also, in fact, had glowing fingers? I'm sure you must have. Also, how high is high energy? Both Potassium and Calcium have naturally occuring radioactive isotopes that emit relatively high energy gammas. Which is why, if you eat bannanas or drink a lot of milk before being internally monitored, you will have a higher whole body count than someone who abstains from ingesting them. Also KCl salt substitutes are so radioactive that they are banned on U.S. submarines. Is it possible that your supersensitive imaging thingamajiggy is sensing these gammas from the hands because thay are not attenuated by a lot of tissue.

Just a thought.

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"If you stick your finger in a pie, whatever is in the pie will be on your finger, and whatever is on your finger will be in the pie...unless you wear a rubber glove"----some demented old lady

Back to the topic of radium paint in wristwatches.

Has anyone ever shown that these watches caused any significant harm to the wearer? I'm familiar with the theory that it was harmful to the factory workers, but it seems to me that they would likely be harmless to the wearer. Radium gives off alpha particles, right? Alpha particles wouldn't be able to penetrate the watch glass to harm anyone.

I've always figured that the reason radium paint was outlawed was because of irrational fear of radiation in any quantity under any conditions, rather than any real health risk.

Sue, you're correct that alpha particles would be stopped by the watch glass. But radium also emits gamma rays, which would easily penetrate the glass.

Despite that, I don't think that radium watches were discontinued because of harm to people wearing them; it was the problems of manufacturing. The radioactivity from a single watch dial is trivial, but if you worked in a factory producing the things, the doses would add up.

We know more about radiation today than we did then, so if there were a demand for radium watch dials now, we could probably produce them safely. But why bother with the radioactive stuff at all? An Indiglo(tm) light is brighter and isn't remotely hazardous.

I thought I would check out this site, because I really enjoyed Cecils last article. In any case, I wanted to add a few things...

To TheDude...nice job, you handled most of my corrections.

The blue glow is in fact due to Cerenkov radiation, to whomever asked.

Lethal dose would depend on several factors. 500 rem would kill about 50% of those exposed within a month. 700 rem would kill almost everyone inside of a month. 5000 rem would probably result in instant death.

No, the watches wouldn't expose you to very much radiation at all. The people who painted the dials were injesting the material. Radium is a bone seeking...so goodbye jaw bones, etc. Not sure what the exposure is to one of these while wearing it, but it would probably be comparable to what dose you give yourself. Yes, that is right....all of you are radioactive!!!

Also, being 100 yards from the bomb blast, those individuals would have died from the heat blast or the force of the explosion, but not the radiation.

Oops..forgot one other thing. Bremsstrahlung is the german word for "braking radiation". This occurs when electrons decelerate inside of a material (thus releasing x-rays). Trust me...it is cerenkov radiation that you 'see'.

This is a bit off the topic, but I would like to know how important it is to wear sunglasses with so-called UV protection.
UV light is composed of short-wavelength, high frequency photons, but these should still be largely absorbed by ordinary glass or plastic. They get scattered very easily (being far beyond the blue end of the spectrum), I think.
Is there empirical evidence that there is special protection needed for the eyes, once they are shielded by a 3mm wall of glass or plastic? What, exactly, is UV protection, anyway?

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The state of non-bliss implies some knowledge.

My Dear Mr. Mollusk --

Must be nice to know barely enough to bring up irrelevant details when you can't understand the facts.

But I see I must explain. The device was *calibrated* to a known radioactive source -- which source depended on which isotope we were looking for. I'm *hoping* you comprehend spectrometry, and that gamma-emitting radioactive isotopes emit those gammas in wavelengths specific to the isotope? When you have good enough spectral resolution, you can narrow the energy band in which you record events to only cover the peak of the isotope you're seeking. If you calibrate a device to a known source, you can make absolutely certain that you're only looking at the peak from that isotope, and the S-to-N ratio is relatively low. I *do* hope I don't need to explain the scientific method to you, too? I try so hard not to be patronizing, but it seems some people demand it. . . .


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". . . and all places are alike to me."
--R. Kipling

I would like to know how important it is to wear sunglasses with so-called UV protection.


UV radiation causes cataracts. How important that is depends on whether you mind going blind or not. From what I remember, glass has no UV protection and only some plastics do. This was from Consumer Reports and they recommended getting shades that claimed UV protection.

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Those who can't hear the music, think the dancer is mad.

In 1922, Radium Dial opened a factory in my hometown of Ottawa, Illinois. They paid up to $17.50/week to local high school girls (a pretty big paycheck at the time: the average pay back then was about $5/wk) and taught them how to paint clock faces with radium in order to make the numbers glow inn the dark. In order to do this, they dipped the brush in the paint and then rolled the tip on the end of their tongues to make a fine point. The plant closed in 1968, but re-opened across town as "Luminous Processes". My spouse has an in-law who worked there until it was closed in 1977, and this in-law's fingernails literally glowed in the dark for years after working there; in order to see this phenomenon you would have to be in a very dark place, such as a closet or a windowless bathroom with the lights off, but one could definitely see the glow. For further investigation I recommend the documentary "Radium City", Produced by Carole Langer and featured on the Discovery Channel some years back.

There are two clock chime tunes, though, "Westminister" and, um, maybe "Big Ben"

I thought "Westminster" refered to Big Ben. Big Ben is located in a tower of the Parliment Building. Across the street is the Abbey. I don't recall ever hearing more than one clock strike the hour, there.

There are two clock chime tunes, though, "Westminister" and, um, maybe "Big Ben"? Both are structured as four quarters, with first just the one part played at ?:15, then two parts played at ?:30, etc. until the whole tune gets played on the hour before the chime counting the hour.

Our family actually had a chiming clock which would play either one depending on the position of a switch, is how I know.

Hence the "um."

All right, time for some research. According to the Klockit home page, www.klockit.com, there are three popular melodies : Westminster (= "Big Ben",) Whittington and St. Michael's.

I remember our clock having a choice between "Westminster" and something else, but neither of those other two . . .

. . . ring a bell.

-j

[We know more about radiation today than we did then, so if there were a demand for radium watch dials now, we could probably produce them safely. But why bother with the radioactive stuff at all? An Indiglo(tm) light is brighter and isn't remotely hazardous]

Indiglo may be heaven sent however, the "old" technology of using radioactive paints to make watches and other objects (night sights for firearms) glow is still in use. The radioactive (mildly so but still dangerous see: http://drambuie.lanl.gov/~esh12/inkret/DAh3.htm) is tritium.

I knew a watchmaker next door who's hands shook like crazy. I don't know how he ever worked on watches. He said that the radium in the old watch hands is what caused it.

It might be just a little, but when you work with it day after day eventually it has a profound effect.

Even seeing the new glow necklaces makes me nervous.

[dcroy]

I don't have any citations for this and I can't even remember where I heard it, but I recall the lyrics to the bell song being "Hail to the bells/ we bow our heads/ We thank the Lord/ our daily bread."

[Loren Pechtel]

Originally posted by TheDude:
Narile has the basic idea correct, but some of the specifics are mixed up.

Everything you said is correct (other than about radium decay--I don't know to confirm or deny.) However, you missed one type of radiation: neutron. It's the worst one--for a given energy it does far more damage to the human body. Also, unlike the other forms, it's liable to make whatever it hits radioactive.
Fortunately, natural decay sequences normally don't include neutrons. However, you do sometimes see them from the byproducts of fission.

Also, to clarify something: Externally, alpha and beta emitters pose basically no risk. Very few beta particles make it deep enough through the skin to affect tissue that remains--most all will be absorbed in the skin layers that will soon be shed. The real danger from such isotopes is when they get inside your body. Then you aren't shielded from their harmful effects.

[Loren Pechtel]

Originally posted by Squid Vicious:
100-500 rem, all the things you think about radiation, hair loss, teeth loss, vomiting, etc. 50% will die. over 500 is almost certain death. over 1000 rem is instantaneous death.

Anyway I hope that helps.


From some older data I've read about this: It's only in the upper part of the 100-500 range that kills 50%--and that's assuming no treatment. At that level, the radiation kills the bone marrow. If enough of it dies and you don't get treatment, you die. However, even if it all dies, treatment is still possible--bone marrow transplant. You'll be in for several quite unpleasant weeks and might die anyway, but you've got a fair chance. If it kills, it kills in like a month.
Beyond this level is disruption of the digestive system. This is in the 1000 rem range. Death occurs in 48 hours, there is no treatment last I knew. (Such cases are exceedingly rare--even if someone had an idea of how to treat it, they wouldn't have gotten a case to work on.) Finally, at a few thousand rem there is central nervous system disruption. Kills in 24 hours, unconcious in a few minutes. These are also exceedingly rare. The only case I heard of the guy lived long enough to run out from the building--even at that level it's not instantaneous.
Obviously, the higher the dose the faster it would do it's harm. However, it's a realm with very little data--the only cases I've heard of came from unintended criticalities while processing nuclear materials.