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Geiger Counter - and what’s needed to detect radium


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Well I got a Radex RD1212-BT Outdoor edition - obviously so I can take it off roading in a hurricane. Actually it was nominally more expensive than the base model but offered with next day Amazon Prime delivery. 
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Fired it up and tested it on my suspect dial...nothing. Nothing at all. Well, it did indicate 0.10 background radiation. I suppose that's good but part of me was hoping it would indicate Radium just so I could see it work. 
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But this poses a question for me - this particular device only detects Beta, Gamma, and X-Ray. NOT Alpha. I'm no nuclear scientist so here comes my dumb question: do I need a geiger counter that detects Alpha particles to determine if I have a Radium dial?

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I am, I mean a nuclear Engineer and can assure you, a repairman doesn't intake  any worrisome dose of radioactive material, unless you decide to have a radioactive Omlet. 

Alpha is the nucleus of Neon and absorbs electrons first chance 

, so it only travels like 5 cm in air.

I would keep radioactive luminants out of childerens reach. 

Most modern luminants are not made of radioactive material.

And not practical to protect yourself from background eletromagnetic radiation unless you wear protective clothing made out of materials that shield you from gamma or beta. 

so, No need to spend money on geiger counter. 

 

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1 hour ago, Nucejoe said:

Alpha is the nucleus of Neon

No it isn't.

An Alpha particle comprises 2 neutrons and 2 protons, making it a Helium nucleus.

The atomic number for Neon is 10, so has 10 neutrons and 10 protons.

4 hours ago, mzinski said:

do I need a geiger counter that detects Alpha particles to determine if I have a Radium dial

No, Radium is primarily an alpha emitter, although does also emit beta and gamma. If your detector picks up alpha then it will detect Radium. 

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1 hour ago, Marc said:

Alpha is the nucleus of Neon

I think that is a typo. Alpha particles are in essence Helium, or if you want to be more specific a Helium 4 nucleus. They are also easily absorbed by pretty much anything, so they provide limited scope for damage to tissue, unless of course as Nucejoe  says unless you add the radium to your lunch, you are probably fairly safe.

There is a full discussion of the issue here.

 

As to uses for radiation detectors like yours, they are quite interesting devices to play with. Mainly they detect beta and gamma radiation, which means they will detect something from the radium hands, just not the majority of the radiation which is Alpha.

Most commercial radiation detectors fall in to the category of beta and gamma or gamma only detectors, for a couple of reasons.
First, alpha radiation is fairly easy to protect against, and most of it will be blocked by clothing or a thin barrier of paper, and therefore is far less of a problem than beta and gamma radiation. Secondly, and for the same reason, making a detector that is sensitive to alpha radiation is more problematic, since whatever you make it from, must allow alpha particles to enter the detector, while protecting the detector from the environment.

I have a couple of devices that detect emissions from old watch dials, (radium and later tritium dials). They don't detect the alpha however, but you can estimate the alpha from the amount of gamma and beta they detect, so I suspect your device should work the same way.

 

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1 hour ago, Marc said:

No it isn't.

An Alpha particle comprises 2 neutrons and 2 protons, making it a Helium nucleus.

The atomic number for Neon is 10, so has 10 neutrons and 10 protons.

No, Radium is primarily an alpha emitter, although does also emit beta and gamma. If your detector picks up alpha then it will detect Radium. 

Good you noticed my mistake Marc, thank you.

Yes, It is the nucleus of helium. I see I also shortchanged a couple of S and C out of luminescence.

Helium nucleus is massive and heavy and undergoes interactions to absorb two electrons. Being massive wont get too far from the source, as long as not ingested to have a chance to stay within our body we are alright with low dose. We have been living with the dose we get in food and water.

 

 

 

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Below is a video of a Peltier cloud chamber. It gives you the ability to see charged particles emanating from a radioactive source. They demonstrate several objects including the source from a smoke detector and a radium lumed watch hand. It even picks up cosmic and environmental radiation. Fascinating, and pretty eerie to watch.

 

Edited by FLwatchguy73
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One further point. That watch dial looks fairly recent, probably 60s or 70s however it only says Swiss Made
Generally if the dial did contain radioactive material it would be tritium, which as far as I recall is only a relatively low level beta emitter.

BUT

The if my estimate of the age of the dial is correct, then the dial would then generally say

T - Swiss Made - T

Where the T stands for Tritium. This has been a requirement in the Swiss watch industry since the 1960s

I suspect therefore your dial and hands are Zinc Sulphide lumed, which is almost completely radologically inert, and not a particularly effective lume.

There is an interesting article on lume here -> http://www.kronometric.org/article/lume/#4.0

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@FLwatchguy73 Thanks. A very well presented demo of a cloud chamber. Lots of different stuff being observed. 

On my winter projects list is a cloud chamber. It entirely failed to materialise last winter, so perhaps this winter.

They are fascinating to sit and watch, but most of the ones I've seen over the years required liquid nitrogen (or perhaps dry ice) to cool the chamber. I have a couple of peltier coolers which I *may* be able to used for this purpose. I'll need to do some google trawling to see if I can find an easy to replicate design. If you want to learn a little about the history of cloud chambers (and their connection to Scotland's highest mountain), there is a good introduction on Wikipedia -> https://en.wikipedia.org/wiki/Cloud_chamber

EDIT: I wonder if I can re-purpose all of the alcohol based hand sanitizer that will be  hopefully be in the bargain bins this winter as a cloud source media(*).

 

(*) Not that kind of "cloud source". The physical type.:D

 

EDIT2: Some inspiration - https://www.instructables.com/id/Peltier-Cooled-Cloud-Chamber/

https://hackaday.com/2012/09/24/an-actively-cooled-cloud-chamber/

https://hackaday.com/2019/01/13/see-the-radioactive-world-with-this-peltier-cloud-chamber/

EDIT3: https://www.cloudylabs.fr/wp/expansion_cloud/

 

Edited by AndyHull
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someday when the plague goes away and life somewhat returns to normal maybe you could find somebody locally that has radium hands you can check out your detector.

the Geiger counter I have was purchased as a partial kit from a company called maplin the reason for the partial kit I already had the Geiger counter tube. it has a small end window type tube zero idea how well it's calibrated. Has three separate ranges labeled 0.5, 5 an 50 mR/hr.

turning it on in the room and the lowest sensitivity every now and then it makes a little chirping sound far enough apart that you wonder if it's broken and then reminded by a little chirping sound.

I thought I had banished everything to a faraway location in the house but for some unknown reason there is a bag of brand-new hands of mixed type some of them are blue steel gold color and some have that familiar green colored stuff in the hands.  not really desiring to search through the bag for which ones specifically radioactive so as I approach the bag at about 8 inches away the background occasional pop slowly increases at 3 inches you definitely seem to have something that might be radioactive. Holding it up to the bag moving around looking for whatever's most radioactive it looks like I'm getting something in the range of 0.3 to about 0.4.

then what else would I have that has radium nearby? Oh my favorite little baby Ben alarm clocks chrome case black dials patent dates of 1920 in 1925. For this I need to change the scale now it's on the five MR scale. Looks like one of the minor problems of small in window tubes it's hard to get it exactly where it needs to be. But I'm easily getting 1.5 and in the right place it will go a little over 2 MR

another way if you're not sure if your clocks or radioactive you could try an experiment leave the country go to Canada attempt to come back see what happens. The local chapters around here and the Canadian chapter to the north have a summer picnic and two separate people I don't think was on the same weekend I think it was a couple years apart attempted to return to the US with it ships clock one of those ones with those nice big hands covered with? They both had the weight while they search the car. So the border crossings are much more sensitive to radioactive things I was told that even the fire trucks now all have radiation detectors on them and not sure if I want to know why that is.

 

 

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This one requires no cooler, but instead uses pressure changes to super saturate the alcohol vapour. 

A very simple design. The high voltage source is most likely recovered from one of the many dollar store type  low cost fly swatter ones, or pretty much anything from the usual suspects on ebay. Try this ebay search -> "12v high voltage generator"


The black  silicone disk could probably be substituted with a piece of bicycle  inner-tube or maybe even a party balloon, and perhaps you could use an aquarium fish tank pump and a release valve to pulse the pressure to give you more controlled or continuous flashes of saturated vapour. Lots of useful ideas.

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4 minutes ago, JohnR725 said:

someday when the plague goes away and life somewhat returns to normal maybe you could find somebody locally that has radium hands you can check out your detector.

A quick search on ebay, and you should be able to find scrap watches and dials for pennies. Look for anything from the 1900 to the 1930s with lume, and you will most likely have radium unless it says safety lume or some such on the dial, in which case it is probably zinc sulphide based. This kind of lume is ubiquitous at that time.

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On a larger scale, if anyone has ever paid a visit to a scrap metal yard and wondered what the large panels on either side of the drive on weight scale were, they're radiation detectors. Radioactive materials can permanently contaminate other metals when they're melted down among a large list of other obvious issues with contamination.

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22 minutes ago, FLwatchguy73 said:

Smoke detectors have a small source of Americium-241. Your Geiger counter should easily detect that.

.. and you can pick those up from ebay for pennies too.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313.TR3.TRC2.A0.H0.Xamericium.TRS0&_nkw=americium&_sacat=0&LH_TitleDesc=0&_sop=1&_udhi=4.04&_odkw=watch+dials+lot&rt=nc

They are mildly hazardous, so if you do pick one up, store it in a suitable metal container.

I bought one a couple of years back and it arrived in a grubby paper bag, recovered from smoke detector e-waste from some random Chinese seller, so be aware that you are not getting quality, and that there is every probability that this contravened every international radological standard known to man, however it is such a low level source that I doubt if any of the radiation left the bag.

I guess the joke is on us, since in all probability this e-waste was exported for disposal to China from the supposedly developed world, then recovered and sold back to some idiot in Scotland. :D
You could of course cut out the middle man and recover one from a smoke detector locally. Just don't go splitting open the capsule that the Americium is in, as that might prove a little more hazardous. Another reason to wash your hands. It keeps Corona virus and Americium out of your system.

EDIT: Also be aware that not all smoke detectors are Americium based, some use a trick involving infrared and quite literally smoke and mirrors.

Edited by AndyHull
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4 minutes ago, FLwatchguy73 said:

if anyone has ever paid a visit to a scrap metal yard

There was a large (slightly dodgy looking) scrap yard near where I worked, years ago in Coatbridge. Their party piece seemed to be crushing camping gas cylinders in old cars, just for the bang. Coatbridge wasn't the most happening place, so I guess you made your own entertainment. ^_^

 

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Re scrap yards: I remember reading a while back that there was an issue with Chinese imported steel alloys showing up radioactive. Seems they were recycled, and certain medical equipment gets dosed high enough to start emitting some band or another. When it gets recycled, the whole lot becomes an emitter. The point of the article was if your purposes need to be not radioactive, be super careful sourcing material... 

A year or so after that, I was working for a software startup in the hip part of town. We out grew the office, and moved into a recently decommissioned hospital. They really weren't ready for prime time, but rent was cheap. Out front, there were a few dumpsters, and a ton of really nice looking 1/4" steel plate that came from some corner of the hospital. I snagged several plates, and tossed them in my truck bed. In the back of my mind, that story about radioactive recycled stock coming from recycled medical equipment loomed. It's still sitting uncut in a corner of the shop... I keep telling myself I'm going to get a geiger counter or something some day and see if it's clean or not before I vaporize any of it with a welder...

Meanwhile, I live in the mountains just above a Lockheed facility. Lots of top secret stuff, Mars rover bits (I'm told), Titan missiles, and other spooky fun. The guy who lives across the street from me is a 90 year old Bavarian rocket surgeon who retired from that facility. I recall his son in law telling me he holds a patent on a type of radiation detector. Seems applicable given the alpha particle detection conundrum. I may need to poke him and see if he has any prototypes kicking around in a box or something that might be able to solve my steel mystery.

https://patents.justia.com/patent/4104523

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the scrapyard stories are really horrifying stories. it's far too easy for bad stuff to get out in the world and end up in places where it shouldn't be an unsuspecting people pay the penalty. this is why radiation detectors are supposed to be at all scrap yards and hopefully the  scrap dealers aren't looking the other way.

 if you're looking for it something to detect you could do what the Boy Scouts do enhance things a little bit.  Who cares about terrorists when you have Boy Scouts living nearby. okay to be fair you only need one Boy Scout incredibly brilliant and incredibly stupid all at the same time.

https://youtu.be/G0QMeTjcJDA

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1 hour ago, JohnR725 said:

Who cares about terrorists when you have Boy Scouts living nearby. okay to be fair you only need one Boy Scout incredibly brilliant and incredibly stupid all at the same time.

I read "The Radioactive Boy Scout" a few years back. It is interesting to see quite how much radioactive material he managed to obtain, and the antics he got up to with it.

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  • 2 months later...
On 6/18/2020 at 1:39 AM, Nucejoe said:

I am, I mean a nuclear Engineer and can assure you, a repairman doesn't intake  any worrisome dose of radioactive material, unless you decide to have a radioactive Omlet. 

Alpha is the nucleus of Neon and absorbs electrons first chance 

, so it only travels like 5 cm in air.

I would keep radioactive luminants out of childerens reach. 

Most modern luminants are not made of radioactive material.

And not practical to protect yourself from background eletromagnetic radiation unless you wear protective clothing made out of materials that shield you from gamma or beta. 

so, No need to spend money on geiger counter. 

 

I went on an ill-advised shopping spree on eBay last year because i was very interested in some early 1900s watches. And only after they arrived did I find out about radium.

:startle: 

I bought a Geiger counted and found most of what I bought to be quite reactive. I thought the concern with working with radium was accidental inhalation of radium particles into the lungs? Is that something I don't need to worry about as much?

Any thoughts about how to "clean" off the radium safely -- I assume outside?

I've left all that material sealed up in a metal container facing a lead block since I took those readings... 

radium-fun.thumb.jpg.0e8bdc5f8c5dcecb5d4e692033f48b6e.jpg

 

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1 hour ago, firebynight said:

I thought the concern with working with radium was accidental inhalation of radium particles into the lungs?

Yes as in working in a factory for many years or using it as make-up as the poor "radium girls" did.

Quote

Is that something I don't need to worry about as much? Any thoughts about how to "clean" off the radium safely -- I assume outside?

Worried buyers like periodically show up having absorbed already a detectable amount of paranoia. There is no way one can get sick/affected/slightly glowed by handling an old set of hands. If you don't believe that search medical journals on the matter -  radium is a carcinogen but quantity and length of exposure do matter.

Edited by jdm
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1 hour ago, firebynight said:

1900s watches. And only after they arrived did I find out about radium.

you don't have to have ancient watches to have radium. I was looking at a hand assortments these are brand-new hands on pieces of paper so each of the hands are Nice and separate notice that some of the hands which I assume have radium have actually darkened the paper behind them. But the brand-new hands that obviously have been around for a while.

1 hour ago, firebynight said:

Any thoughts about how to "clean" off the radium safely -- I assume outside?

the best approach would be to not clean up your radium. Think of radium as a sleeping Tiger it would be best to keep it sleeping. If you start to clean it usually require chemicals solutions rubber gloves you going to end up with a lot of radium spread all over the place and it's still radium. It'd be just best if you left it alone.

5 minutes ago, jdm said:

Threads like this periodically pop up with a detectable amount of paranoia. There is no way one can get sick by handling an old set of hands. If you don't believe me search medical journals on the matter -  radium is a carcinogen but quantity and length of exposure do matter.

I guess a better question would be not so much for watchmakers handling units because there is a conceivability when putting the hand on having her face so close maybe you breathe in a particle. But what about the consumer? Are there any documented cases of someone wearing a wristwatch and getting cancer? Think of all the years we had watches with radium hands that are still out there with radium how many cases of cancer?

Or I was trying to think what would give us the best exposure to radium to try the experiment not really? Dollar watches especially those with glow-in-the-dark hands that would probably be the most radioactive thing you would have because the hands of the physically be bigger lots a radium and you're probably carrying it in your pockets. So how many cases of cancer from that is there anything documented at all?

maybe ignorance is good if you don't know their radioactive then you don't have anything to worry about. But if you'd like to worry I have some a link.. if you look at the link the watch on the left isn't that a pocket watch with a really big hands? But maybe we got an answer from the link? Notice they're not concerned about you carrying the pocketwatch in your pockets that are not concerned about wearing it on the wrist there only concerned about the other effect of having radium or specifically exposure to radon

https://www.kingston.ac.uk/news/article/2068/15-jun-2018--second-world-warera-wristwatches-could-pose-cancer-risk-due-to-radon-exposure-according-to/

this link is interesting in that a point out the evils of radioactive materials especially those people who look their paintbrushes but you get to the bottom of the page and? As long as you leave your radium stuff alone and don't poke at it or don't try to clean it up yourself your fine. So they don't seem to be upset about wearing a radium watch in an article where they're concerned about radioactive stuff.

I guess if you're really worried about your radioactive hands put them somewhere safe otherwise don't worry about it but definitely do not try to clean it up yourself maybe can find a modern replacement

https://www.epa.gov/radtown/radioactivity-antiques

 

 

 

 

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20 minutes ago, JohnR725 said:

Are there any documented cases of someone wearing a wristwatch and getting cancer?

Apparently there are not. I have attached the study that you mentioned, which contains a lot of measurements and concludes:

Quote

Our research has confirmed that radium dial watches individually are a modest health risk to wearers. 

If there were documented clinical cases these would have been mentioned in there, or in some other in bibliography.

Crockett_Robin_E_2012_Radium_dial_watches_a_potentially_hazardous_legacy.docx.pdf

Edited by jdm
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22 hours ago, JohnR725 said:

Are there any documented cases of someone wearing a wristwatch and getting cancer?

Given the relatively low dose it causes, even over a lifetime of wearing it, and given the large number of other radiation sources, it would be almost impossible to prove that a watch had given any one individual cancer.

Statistically though you could estimate on the balance of probability the likely hood of it doing so.

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