Hey Clive don't know if you'll see this comment but the reason it is called "Vaseline Glass" is uranium glass manufactured before the 1890's-1900's used to be a semi transparent yellow that looked fairly reminiscent of a certain petroleum based Jelly. After the 1900's though they mainly switched over to producing a more vivid Green glass that appealed better to the masses. They made this by also adding Iron Oxide along with the Uranium. I have personally collected a bit of it at Resale shops I frequent using a High Powered UV light I 'Built...'
Whats funny is most people from most countries are OK folks. It is the dumb government's doing all the hating. The internet has gone a long way though in showing most folks have similar interests and are nice people.
Michael O The media is the most powerful political party in the world. A story can start A war. And it doesn't have to be true. There is no way we can varify the truth. The truth needs proof, but plausibility only needs belief. And if something is heard long enough, people will believe anything.....
if you have barely any interest in important issues that may be true. if you like animals by example, there is rarely room on the planet to stay friendly. bullfighting in spain, whalehunting in norway, peltfarming in hungary, geesefeather farms in poland, dogmeat in switzerland, ... and thats just europe. if you dont care for these things youd get along well with them, but i do.
Andrew Kitayev I am a Radio Ham from Liverpool and regard the Russian Radio Amatures as the best in the World they are absolutely Brilliant at Building the own Transceivers that work really well. ..US Hams on the other hand tend to buy there Radios from Japan LOL. ....Regards from Liverpool UK
Hello from Germany! My first Geiger counter and oscilloscope were soviet. The Geiger counter at the time was beyond what the Bundeswehr had at the time.
It was Soviet communism that was bad, not Soviet people. Funny how ideology can create image for entire nation. And when you realise that most people were communists just for profit or fear of persecution... Soviet communism and Russian mafia are two things people in West associate with Russia. I am from Polish family, Jewish family, my grandgrandfather fought in Polish-Soviet war, my grandfather was in British army in WWII and we were heavily persecuted, for political reasons, so no love for communism and Russia. My grandparents even said that they hate Russians more than Germans, when Nazi regime sent bulk of theyr family to concentration camps. People are just scared by historical experiences, there are deeply rooted issues from past and Russian politicians aren't making it better. I also know bunch of Russian folks that are fine, I work with them daily and they know theyr technical stuff. As always, when politics are involved, everything goes awry.
Hello from the Czech Republic, Clive. I hope you enjoy our uranium! Thank you for your videos - as an electrical engineering student, I really love learning new things from you :)
Was that a genuine (TM) Apple (C) Super-Zoom (R) or just a knock-off? The way to distinguish them is pretty straightforward: did that box cost more or less than £400 ?
The slight downside of that circuit is that neons often contain a tiny amount of radioactive material in the electrodes to ensure they light reliably in dark environments.
Vaseline glass - The most typical colour of uranium glass is pale yellowish-green, which in the 1920s led to the nickname vaseline glass based on a perceived resemblance to the appearance of petroleum jelly as formulated and commercially sold at that time. ....and now you know :)
Out of all english speaking Russians, the ratio of friendly people to trolls is about the same as the rest of the internet. I met some very cool dudes playing online games that I would still consider friends to this day. It's quite silly to get influenced by media calling a group of people evil when you can go online and talk to them directly, only to realize that they are exactly the same as you.
Exactly how the media demonizes anybody with view points or opinions that aren't extreme far left, calling everyone they disagree with Nazis and racists and all that crap, telling their followers to attack anyone who happens to have a different view point then theirs. It will start a war very soon if they don't stop, or aren't forcibly stopped. And it's a war they will lose very quickly.
There's a kind English speaking Russian in one of my regular Twitch chats, my best 'chat buddy' is Russian. I have nothing bad to say. The media lies very much. I don't watch it. Learned to look more at people as just that, people, over the years.
For what it's worth, if you're still curious: They're nicknamed "Vaseline glass" because the yellow-ish color of the marbles resembles early 1900s petroleum jelly.
When Clive placed the thorium mantles next to the Geiger counter, it spiked from about 1.2 µSv to just under 5.6 µSv. As examples, the background dose received by an average person over one day is 10 µSv. Also, an airplane flight from New York to LA would equate to 40 µSv being absorbed by the body, and the average yearly dose a radiation worker must be limited to is 50 mSv. Furthermore, a fatal dose is generally considered to be between 4 to 8 Sv in one exposure. Finally, if one was unfortunate to have been standing next to the Chernobyl reactor core after the explosion and meltdown for about ten minutes, then one would have been 'hit' by a massive 50 Sv dose all at once.
You've inspired me to buy one of those and some of the radioactive marbles and glass from the Czech republic I look forward to getting on that and experimenting thank you for being an inspiration
The GM tube you are working with can only detect gamma radiation even if other radiation is being given off. Other GM tubes can detect alphas or betas. This is why the aluminium only attenuated the radiation by a small amount. Also, the distance from the source (mantle) will be very significant. Great video by the way. Thanks.
Uranium gives off alpha particles. Also the vaseline glass term comes from the fact the most typical color of uranium glass is pale yellowish-green, which in the 1920s led to the nickname vaseline glass based on a perceived resemblance to the appearance of petroleum jelly
Thorium 232 as used in gas mantles is predominantly a gamma emitter. It decays to Radium 228 which is a beta emitter. Thorium 230 is also present in gas mantles in trace amounts and is an alpha emitter. Th230 has a decay path that includes Radon gas. So basically, an old gas mantle will not only emit alpha, beta and gamma, it will also give off a radioactive gas.
Thorium decay emits alpha particles as I understand it, but it decays to Radium and Radon which emit beta and gamma radiation, and that's what the geiger tube is detecting. So presumably that'd mean that gas mantles become more hazardous with age. If you open the bag Clive do it outdoors.
Given the half-life of thorium, I don't think the age of the sample is going to be terribly relevant. The daughter nucleides decay more rapidly than thorium so they generally won't accumulate.
I have many times walked into a thrift shop looking for old Green and Blue glass plates that are "Radio active" with my 1950s style counter. Fun stuff.
All natural uranium isotopes emit alpha particles. They have very low beta and gamma activity. Thorium has the longest half-life of all the significantly radioactive elements, 14.05 billion years; it decays very slowly through alpha decay to radium-228, starting a decay chain named the thorium series that ends at stable lead-208.
I think depleted uranium is an alpha emitter, but it does decay into a few gamma and beta emitters. This is because uranium-238 decays directly to thorium-234, which with a half-life of 24 days decays to protactinium-234, which in turn decays in a matter of hours to the long-lived uranium-234. A quasi-steady state is therefore reached within a few multiples of 24 days. Uranium-234 is actually so stable, it has near negligible radioactive danger, and is actually more of a chemical toxicity concern.
Uranium and thorium are both alpha emitters, but they also emit gamma. The proof off that for thorium is in the video here. Neither alpha nor gamma radiation can pass through aluminum,but gamma can, so the counts coming from thorium through the aluminum are gamma.
Hmmm, while Thorium itself is only mildly radioactive, and is an alpha emitter, which is blocked by paper, glass, metal et cetera, it's decay products include radon and radium which are much more dangerous. If you're getting a reading through the plastic bag and even through the aluminium plate, then that's not just Thorium you've got in the bag.
Thorium does NOT decay to radon.....it DOES decay to Thoron though. Radon comes from Uranium(really from the Radium component of Natural Uranium). Pure Uranium does not contain Radium, and thus no Radon. And Radium comes from Uranium, NOT Thorium.
Sorry, but Thoron? Thorium definitely decays to Radium, then Radon, Polonium and Lead. Here's a picture of the chain: en.wikipedia.org/wiki/Thorium#/media/File:Decay_Chain_Thorium.svg
Hi Clive. Uranium glass emits both beta and gamma. I tested a piece I recently bought with a sheet of paper between it and my geiger and the and it read the same, indicating beta + gamma at least. My GC isn't sensitive to Alpha. Then when I placed a folded aluminium sheet between the two did the reading go down, indicating gamma only. That thorium mantel, if it emits gamma, then your dad's night stand would have not blocked it.
Very sorry to hear about your Dad, it is a thought though, were there many in the draw? My uncle studied Thorium (Th232 specifically) for many years as a Nuclear Physicist for the purpose of providing us with energy instead of Uranium because of the abundance of Thorium and it's less dangerous. It makes little sense why we do not already use it because it essentially breaks down to the same Uranium isotope U233 once it absorbs a Neutron (you need a neutron source) U233 is the isotope in Uranium reactors all over the world!!!!
You should check Cat Litter and Toilets Bowls with your meter...the clay used to make Cat Litter and Toilets (at least in Canada & the USA) is slightly Radioactive (not dangerous, just a little above ambient)... Every time I took a load of Cat Litter from Ontario to the USA (former Truck Driver), the Boarder Crossing would go nuts because my trailer set off the Radiation Sensors at the Customs Booth...
These counters only really detect Gamma as the tube itself will block out nearly all the Beta rays. As for alpha well that won't even get through the air let along the tube wall. Don't ingest Alpha sources though, then they are much more dangerous than Beta and Gamma.
I know this is a really old comment but should let you know that is incorrect about the tubes. The SBM20 variants are very sensitive to beta. I have used them extensively to detect both milder U-glass and pottery glazes. They are great for that. Also, alpha can travel about 1" through the air but cannot penetrate that tube wall - unlike beta and gamma. Got some vids on my channel but nothing as cool as Clive does. :)
I’ve had Over a dozen packs of vintage lantern mantels in my vehicle glove box. The glove box sits between the driver and passenger seat. I do a lot of fishing and traveling, and I keep several Coleman lanterns in my truck toolbox and all of the extra packages of mantels in my glove box. I’ve spent at least 300 nights sleeping in my truck driver seat over the past 10 years. With my head literally inches from the lantern mantels. I have several Geiger counters, and the lantern mantels never occurred to me. However I recently checked them with my SBT10 and SBT11-A tubes… And indeed they are radioactive. I reclined my driver seat and measured the exact distance of my head to the mantle’s, which varies between 9 and 14 inches depending on which way my head is turned. I do a lot of traveling… One winter in particular I slept in my truck every night for five months solid! Traveling looking for musical instruments and other interests… I’m just more comfortable in my truck than checking in and out of a hotel twice a day. I’ve been traveling out of my vehicle part time for the past 13 years. And I’ve had those lantern mantels there almost the entire time. I Purchased a large box of mantels from a small town family owned hardware store that had been in business for 40 years. They were going out of business and about 15 years ago I purchased an entire box full of mantels. Probably a gross (144) but I’m not quite sure. The glove box is at least an inch thick on all sides, made of leather, nylon, and plastics. Curious if I could pick up radiation damage with this prolonged exposure? When I get my new counter( and extremely sensitive tube) within the next few weeks… I will measure from the outside of the glove box and see if the radiation makes it through. Would really appreciate any feedback. thanks for the great video
A little ramble, as the video goes on:It's held at 300-ish volts, that is an SBM-20 Russian/Soviet tube. Pretty much the benchmark tube for DIY/low-end counters. The voltage is feedback-based, using an ADC on the controller and a dividier. It's a boost converter feeding into a relatively(!) large cap. Uranium is an alpha emitter, but the decay chain emits soft gamma that you're detecting. Thorium is a gamma emitter. I'm from Belarus, speak Russian, and I highly disagree with you on the "cool dudes" part. I've been consuming almost exclusively western content because I really dislike our segment of the interwebs. Oh, and the little dinky iPhone devices are so insensitive they're absolutely useless and pretty much a scam.
+Spirit I reckon the iPhone detectors may be based on the blacked out photodiode circuit. The schematic for this Geiger counter does not show voltage feedback circuitry. It seems to be based on a calibrated oscillator drive to the step-up circuit. So I'd be suspicious of its reliability at high count rates.
bigclivedotcom It's a resistor connected to the diode(BPW34, google it, it's quite a fun and easy project with it if you actually build a power supply for it) directly, then driven by "speaker" output and listened to by the microphone. The sensitivity is so miniscule it's not going to work, ever. I remember someone shoving it into an xray machine, that only raised the count to a measely "dangerous" and ~80CPM. There's not enough power to make an oscillator.
I watch some videos that are Russian. There's some English in some videos. I don't know Russian very well. I know the Russian alphabet, so I can make out some words and speech, but the ones I watch are fantastic! Those Russians are gifted! Very passionate about what they do! I love it! And I'm from the US. Governments are often what give foreign people bad names.
I still have a tiny tin of Humbrol Luminous paint. Some of the paint is on the lip of the tin. I keep it in a garden shed on a high shelf but at night when you open the door there it is - GLOWING GREEN. The new phosphorescent paints are called 'luminous' but need a light source to recharge them. This old Humbrol paint manages very well on it's own. I assume it's banned now. After the old Smiths dial factory was closed they found an area where the old paint tins had been dumped beyond safety limits. The soil I believe was put in drums and is now possibly at the bottom of the sea. They might even be off the Isle of Man. Do you like sea food Bigclive? Does your beard give off a faint green glow in the dark ? Have you tried switching the light off in the toilet? In regard to Russian video's on electronic kit. They look good, on average better than many. It's annoying when all you can find in 'English' is some dork mumbling a pathetic 'review' and plugging an amp into a crappy speaker and expecting you to subscribe. Real Russian vodka, it goes down neat like a nectar from the God's. You won't find it in an off licence. People from cold countries have the warmest hearts. You are so right about Russians - englishrussia.com/ They are completely mad of course LOL. Like someone else I know.
Yep, that paint has Radium and some sort of phosphor. Generally, the phosphor degrades over time, due to Alpha bombardment and moisture, which is why most Radium painted items no longer glow.
Gas mantles sold in the EU are supposed to contain yttrium oxide instead of thorium oxide, but ones from China may still be thoriated. The problem with storing gas mantles is not the mild beta or gamma emission but rather the build-up of "thoron" which is actually Rn-220 a short-lived isotope of radon and a significant alpha emitter just like "normal" radon-222. A jar filled with thoriated gas mantles is a good source of thoron to demonstrate half-life in a school or university physics lab. Keep them outdoors if possible!
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I live basically next to them drugi Russians and these tubes come by a pretty penny... not cheap. A working area monitor costs as much as a brand new phone... But the Geiger counter is a useful tool I like having in my tool box and it is the one that I never want to hear buzzing except when I press the ~check~ button.
It won't be measurable with a regular geiger counter. It's so low level that you'd need a lead cave and a scaler geiger counter or a gamma scintillator.
It's not measurable. I have tried it with a Victoreen CDV700. I have some KI and KCl. I can measure those. Background radiation is 12 CPM while with KCl, I think it was 20 CPM. The radioactivity comes from K40 which is sometimes a beta- and sometimes a beta+ emitter.
A lot of people collect WW1-2 to 50s aircraft clocks and other stuff and don't know that those are very radioactive. Anything that has stuff that glows in the dark or at least used to glow and produced before 60s can be very dangerous. Aircraft/railroad equipment, watches/compasses, some switches etc. If you see slightly orange dots, letters, paint on clock hands etc - use Geiger counter. It's not radiation by itself that dangerous (but still dangerous) unless you keep those under your pillow or in your pants but radium paint which starts to fall off and you will inhale small particles causing massive amounts of alpha radiation to wreak havoc on your internal organs, which aren't protected by skin and clothing. One guy had a WW2 aircraft radio that was more radioactive than a truckload of those gas mantles.
Radium paint yes, it was even used on alarm clocks for a while. The 'orange dots' you're mention sound like the paint on old Fiestaware dinnerware, but it isn't used for self-illuminating paint :)
Another great video. I particularly like the zoom... I would also say that if the radiation can still be detected through aluminium, then what you have there is gamma radiation. I would be tempted to store those gas mantles in a lead container, if I were you.
Luke Stanmore - Ionizing radiation does pass through: the trouble being that some of it may like to stay and have a 'look round' as it were. Especially if it hits denser tissue, like bone, or areas with a high density of blood vessels, like the liver, pancreas, thyroid, spleen, genitalia, etc. Ionizing radiation. Be afraid. Be very afraid.
I have a Geiger counter, I calibrate it using an old Westclox alarm clock circa 1950 , it almost goes off the scale due to the radium on the fingers. I don't keep the clock anywhere close.
And imagine that, people would have kept those a foot or so away from their head for maybe years (cumulatively) Cool as a radiation source, but not for actual intended purpose! Keep it the fuck away!
You can determine if those marbles are Alpha/Beta emitters, by placing a piece of thick card between them and the Geiger Counter. If they're Alpha/Beta emitters, the count rate will drop significantly, whereas if they're Gamma emitters, there'll be no change in the count rate.
We used to use one of these but that looked more like a db meter when I was in a x-ray development workshop. Their physics guy taught me that a sievert equates to a joule, why do we need all these units that refers to the same ammount of energy? Anyway I renamed the calorie to Ragnar (Sievert is a name here) after this guy, he was really funny and a good teacher just like you clive.
+rimmersbryggeri "1 Gy is the deposit of a joule of radiation energy in a kg of matter or tissue." wikipedia. Sievert is 1:1 gray for normal tissue and a coefficient for sensitive tissues, so it mostly reflects the damages it does to the body. (ex: 20 for breasts, Thyroid). Also Alpha particles do more damages and have a high Sievert multiplier.
Hi big Clive great video's as usual ,are you going to have a Shot at making one of those photo cell Geiger counters hope you'll have a go .your channel is mint well done
Hello big Clive, the reason it's often called "Vaseline Glass" (ioxide diuranate form) is that the translucent lustre in some ornaments on the glass looks like Vaseline. The proportion usually varies from trace levels to about 2% uranium by weight, although some 20th-century pieces were made with up to 25% uranium. This may interest you? : - Estimates of the Radiation Exposures A very detailed analysis of the radiation exposures due to uranium in glassware can be found in the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG 1717). There are three principal radiation exposure pathways associated with Vaseline glass: 1. Exposure to the body from the gamma rays emitted by radionuclides in the glass. Chemically processed uranium of the sort we are considering here consists of the following radionuclides: U-238, Th-234, Pa-234m, U-234, U-235 and Th-231. The principle gamma rays emitted by these nuclides would be 63 keV and 93 keV from Th-234 and 186 keV from U-235. NUREG-1717 estimated the following exposure rates from two different pieces of glass with 10% by weight uranium content: Distance Drinking Glass Decorative Piece 1 foot 9 x 10-4 mrem/hr 1.8 x 10-3 mrem/hr 3 feet 1 x 10-4 mrem/hr 2 x 10-4 mrem/hr 6 feet 2.5 x 10-5 mrem/hr 5 x 10-5 mrem/hr For comparison, the background exposure rate due to gamma rays is approximately 1 x 10-2 mrem/hr. 2. Exposure to the hands from the beta particles emitted by radionuclides in the glass The aforementioned NUREG-1717 also calculated the beta dose rates at a depth of 7 mg/cm2 (i.e., the nominal depth of the germinal layer of the skin) as well as the estimated effective dose equivalent. It was assumed that the source was a 10 inch diameter plate with a 10 % by weight uranium content. Distance Dose Rate Effective Dose Equivalent Rate Contact 27 mrad/hr 0.0027 mrem/hr 1 foot 1.1 mrad/hr 0.0027 mrem/hr 3 feet 0.095 mrad/hr 4.7 x 10-4 mrem/hr The ratio between the effective dose equivalent rate and dose rates vary with distance because the further away from the source, the greater the area of skin that was exposed. 3. Ingestion of uranium that has leached into food that has been in contact with the glass Landa and Councell evaluated the leaching of uranium into different solutions over a 24 hour period. The glassware they used was designed to hold liquids (e.g., drinking glasses). They determined that the average resulting concentrations of uranium were 0.052 ug/liter (1.7 x 10-11 uCi/ml) for water and 5.9 ug/liter (2 x 10-9 uCi/ml) for acetic acid. The highest measured concentrations were 0.63 ug/liter (2.1 x 10-10 uCi/ml) in water and 30.1 ug/liter (1 x 10-8 uCi/ml) in acetic acid. They noted that less uranium would leach into solution when the experiment was repeated. The presumed explanation is that less and less leachable uranium becomes available. After estimating the effective dose equivalents for a variety of potential exposure pathways, NUREG-1717 concluded that the highest doses would be to the personnel involved in the transportation of the glassware from a manufacturer to a truck distribution center. This maximum estimated dose, 4 mrem/year, is approximately 1 to 2 % of the average American’s annual radiation exposure.
Oh that's very cool Clive: I've always had a fascination about Geiger counter's and now I want one !! But what I thought was really fascinating about your talk is that new telephoto lens for the iPad that seems to work so well. PLEASE can you tell me where you got and was it over 100 dollars in price. As always, good stuff and thanks for the demo.
I always wanted a Geiger counter, being that I live within a few miles of a Nuclear Power Plant. I kinda want to drive by on my bike and see if I can find any difference between here and the plant (of course not on the actual grounds of operation, but definitely close enough to be well within Evac Zone 1).
Very nice! Uranium-238, Uranium-235, and Uranium-234 are alpha emitters. So is Thorium-232. Their many decay daughters also emit alpha, beta, and characteristic gamma rays. That rare earth glow powder (if I had to guess is europium-based) gave your Geiger counter a noticeable increase in counts when you put it close to the tube. It's possible that the REE glow powder could have some traces of Thorium when it was processed from Monazite sand (maybe), or other minerals. Maybe some trace REE isotopes? Gamma ray spectroscopy would let you what isotopes are present. Interesting! Thanks!
Vaseline glass got it's name from it's pale yellowish green colour that resembled the original colour of vaseline. I had an aunt that used to collect it. She lived to be 94!
I don't know if anyone mentioned it yet, but most mantles (Coleman, etc.) on the market now, contain Yttrium instead of Thorium and won't have any effect on a Geiger counter.
I power my SBM20 using a photo flash transformer whose primary is pulsed by an mc34063 which gets its feedback from the HV+ via 2 hv zeners of 200V each. Works like a charm.
Do those Bullfinch Mantles (as seen at 5:10) come in different sizes and could they be used to encapsulate one's scrotal sack as a form of birth control?
Yes, I'm late to the party. Can you find an antique clock that has radium painted hands and numerals? Westclock made then for many years, they can be found on ebay and in antique stores ( the ebay offerings are cheaper even with shipping) the radium on them has a halflife of about 40,000 years and it would make your counter do mucho clicking.
There are a lot of interesting technical English-speaking Russian TH-cam channels. I found one a few weeks ago that talked about the history of the development of Russian Soviet-era computers, showing a few different models and processors and the like. It was very interesting. There were lots of knockoff clones of Intel chips of course, but they also did develop their own. Science in general had an... interesting... time during the Soviet era. You wouldn't think that politics would affect it too much, but it really had a big influence on some parts. Biology was a big one. They opposed evolution on the grounds that it was a capitalist ideology, for instance. I've got an interesting book called 'The Perversion of Knowledge' that was written by a Russian scientist who lived through the time period and became a dissident opposing the Communist meddling (and the horrifying human experimentation). If you're going to do any more Geiger counter fiddling for videos, might I suggest breaking open an Americium-containing smoke detector? Or, if you can find one, a device with the old school Uranium-bearing glow-in-the-dark paint? I had a clock with such paint displaying its numbers as a child but didn't realize what it was until much later. Not sure what happened to it or I'd offer to send it along.
Thorium's primary decay is through alpha radiation, but it's a large particle, and you'd pretty much have to inhale radioactive dust to cause any harm. Uranium primarily decays into Thorium through the same method.
Don't know how many times I got that mantle dust in my mouth from using Coleman lanterns for work because we had no lights to work by ! The new material being used produces a very yellow light
Thorium mantles are quite spicy. I have one of the green dyed ones. It saturates my counter. I keep my samples in a steel steetie can on my bedside cabinet. The radiation still leaks through and that's with the samples wrapped in 4 layers of BACO-Foil and inside a steel can. Looks like your counter uses an SBM-20 tube like mine. Only good for beta/Gamma only. Check out an old fire alarm. Thay generally use an Americium pellet (Alpha emitter) and you counter won't detect it.... or if it does, it will barely detect anything. For Alpha you need a different tube with a mica window and a higher voltage.
@3:20 the Vaseline reference was due to its somewhat similar pale-yellow coloration of Uranium glass....though coloration is highly dependent on the oxidation state of the Uranium used.
The mantles are impregnated with thorium oxide. When you first put the mantle in use, the organic material burns out and the thorium oxide is all that remains. And there comes the crucial detail. Thorium oxide melting point is 3390 degrees C and the boiling point about 4400 degrees C. Pure tungsten melting point is just 3422 degrees. To operate plain tungsten anywhere near 3000 requires inert gas environment, while thorium oxide is already “burnt” and can be operated as those mantles without other concerns than vibration and shock.
+Pellervo Kaskinen: It isn't because of the melting point or boiling point that ThO2 is used. ThO2 exhibits a phenomenon called candoluminescence (or is it candeluminescence). It emits more visible light than some other materials. This is because instead of emitting in the infrared region, some of the energy is stored and emitted in the yellow region. If you want, buy some chalk or get some from your backyard. It is CaCO3. Heat it with a torch strongly and it will convert to CaO which is candoluminescent. Do it in the dark. Compare it with heating some other piece of rock or brick. You can easily tell the difference. This is where the term "being in the lime light" came from. They heated CaO with some torch in theaters. They call CaO or Ca(OH)2 lime (limescale?, lime water? calcium and lime?) in the old days for some reason.
louis tournas : Interesting... Never heard of those details. Although another lamp called Nernst lamp is based on the chalk or more likely magnesium oxide. And makes me speculate that the oxide is the key. After all, burning magnesium was the old source of bright light for photographers. The common item for all these seems to be oxygen. Hmmm...
Tritium emission will be stopped totally by glass. That is why they are safe in exit signs. I have some modern mantles ( made in China) and they are also radioactive, though they have lower levels of Thorium. Must take apart an old ionisation smoke detector and see how active the tiny blob inside is.
The source in an ionisation smoke detector is Americium 241-its primarily an Alpha emitter, so a standard metal or glass wall GM tube won't detect much...A mica window GM tube or other Alpha detector will detect the Alpha-lots of it. A metal or glass GM tube will detect a SLIGHT bit of radiation from it though-even though it's mostly an Alpha emitter, it emits a small amount of low energy Gamma, mostly at 59.5 KeV. This is very low energy, and does not travel far, so no substantial hazard.
I miss those thorium mantels, they gave off the brightest light. Modern mantels are dim by comparison and are much more fragile compared to the old thorium ones.
Modern digital x-ray imaging panels are usually amorphous silicon panels. I believe they detect beta and probably alpha radiation pretty well on their own. I know that for radiotherapy they use a copper sheet or something similar as a scintillator to convert a few xray photons into electrons for the silicon panels, to get an image. Long story short, would be very interesting to try some kind of scintillator in front of a silicon photodiode to see what readings you get.
Get a 9volt strobe light, the type used in alarm systems etc. Remove the bulb, connect it to a battery then put your fingers on the connections for the bulb :D Trust me, 300V is more than a tingle hehe..
A fun project might be to build a true randon mumber generator based on the timing of the blips. (E.g., measure intervals to the nearest millisecond, and take a digit from the middle of each result.
It is based around the Russian tube СБМ-20 which is for hard beta and gamma rays. Which means the tube itself stops the low energy electrons? But I wouldn't trust it with any beta at all.
Just checked, they are thoriated Tungsten and the count is around 0.15/0.17 mills on my counter. Background here is around 0.1/0.12. Nowhere near your mantles I have some somewhere for my Tilley lamps. Keep up the good work!
That GM tube looks like an SBM20, made in Ukraine afaik. Similarly to the Japan/Fukushima thing, Geiger counters became popular in Ukraine after the Chernobyl disaster. I bought a cheap Ukraine built GC a while back and at some point dropped it thus finding out the hard way that those tough looking brass tubes contain a fragile glass tube, it made a heart sinkingly jingly jangly sound when shaken :-( Much to my delight, I found out that replacement SBM20s are dirt cheap! So, £10 and an ebay visit later got my GC working again! Thumbs up.
Now that's something i'm getting, where did you get yours? Do you need to get the tube separately? Thank you, that was interesting! What about Tritium vials?
I got this one from a seller on ebay. Tritium is a low energy beta particle emitter. I'm not sure much radiation would escape through the glass and plastic housing.
As a former angler, I'd be interested to see what reading you'd get from the 'isotope' glow-in-the-dark bite indicators that are used. I've heard they have a half-life of twenty years which sounds fairly weak but I'll have to see if I still have any around that I can send you...
What do you think about the Smart Geiger Nuclear Radiation Detector's sold on Ebay? Are they any good? Where did you get the meter you using in this video? Is that a self-build thingy from Ebay?
They are called Vaseline glass due to the color being similar to the petroleum jelly back then And thorium kinda sucks as it decays into both alpha, beta and gamma radiation.
How did Van Allen measure the radiation when he was surveying the radiation surrounding the earth? I read somewhere that scientists were puzzled as the geiger counter would hit a certain point of readings and then shut down, the assumption was that there was a radiation free zone in the outer layer of the radiation belt, what in fact was happening was the sensor was being saturated and reading zero. Does your counter reach a saturation point where it stops reading radiation?
+Gromitdog1 I've not actually found a source of enough radiation to do that yet. But I watched video of the same model being used in Fukushima and it was certainly managing high count rates.
Gromitdog1 I have a similar counter that use when playing with radioactive stuff. When I hit it with my home made x-ray machine, it goes off the charts then freezes. If I wanted to get accurate measurements, I would need to use one of my survey meters with an ionization chamber. It can measure tremendously higher radiation than the Geiger Muller tube.
Questions arise. if this device is sensitive to beta and not just to gama. Beta comes from potassium, it can be bought as fertilizers for the village economy and gardens, there about 46% of potassium, and in potassium chloride fertilizer are more potassium%! Just do not get it clear that it measures. It would be nice to check
Hi Clive, i have lots of these vaseline/uranium marbles wich i also played with as a kid, i have them in a wooden cabinet besides my bed do you think the woods stops the radiation? Thanks!
Hey Clive don't know if you'll see this comment but the reason it is called "Vaseline Glass" is uranium glass manufactured before the 1890's-1900's used to be a semi transparent yellow that looked fairly reminiscent of a certain petroleum based Jelly.
After the 1900's though they mainly switched over to producing a more vivid Green glass that appealed better to the masses. They made this by also adding Iron Oxide along with the Uranium. I have personally collected a bit of it at Resale shops I frequent using a High Powered UV light I 'Built...'
Whats funny is most people from most countries are OK folks. It is the dumb government's doing all the hating. The internet has gone a long way though in showing most folks have similar interests and are nice people.
Michael O
The media is the most powerful political party in the world. A story can start A war. And it doesn't have to be true. There is no way we can varify the truth. The truth needs proof, but plausibility only needs belief. And if something is heard long enough, people will believe anything.....
Willy Bee very well said, divide and conquer is the medias mission
Michael O Well Said mate 👍👍👍
if you have barely any interest in important issues that may be true. if you like animals by example, there is rarely room on the planet to stay friendly. bullfighting in spain, whalehunting in norway, peltfarming in hungary, geesefeather farms in poland, dogmeat in switzerland, ... and thats just europe.
if you dont care for these things youd get along well with them, but i do.
I read this in Brak's voice.
Hello from Russia! Thanks you perceive us normally. :)
I love your vids. Thanks for you work!
Andrew Kitayev I am a Radio Ham from Liverpool and regard the Russian Radio Amatures as the best in the World they are absolutely Brilliant at Building the own Transceivers that work really well. ..US Hams on the other hand tend to buy there Radios from Japan LOL. ....Regards from Liverpool UK
Приве́т :-)
@@stevejones8665 Well said. I'm GM1SXX and I talk to a lot of Russian people on the radio. My logbook is chokka with Russian contacts.
Hello from Germany! My first Geiger counter and oscilloscope were soviet. The Geiger counter at the time was beyond what the Bundeswehr had at the time.
It was Soviet communism that was bad, not Soviet people. Funny how ideology can create image for entire nation. And when you realise that most people were communists just for profit or fear of persecution... Soviet communism and Russian mafia are two things people in West associate with Russia. I am from Polish family, Jewish family, my grandgrandfather fought in Polish-Soviet war, my grandfather was in British army in WWII and we were heavily persecuted, for political reasons, so no love for communism and Russia. My grandparents even said that they hate Russians more than Germans, when Nazi regime sent bulk of theyr family to concentration camps. People are just scared by historical experiences, there are deeply rooted issues from past and Russian politicians aren't making it better.
I also know bunch of Russian folks that are fine, I work with them daily and they know theyr technical stuff. As always, when politics are involved, everything goes awry.
Hello from the Czech Republic, Clive. I hope you enjoy our uranium! Thank you for your videos - as an electrical engineering student, I really love learning new things from you :)
+1 for the super apple zoom
audiocrush feature
Was that a genuine (TM) Apple (C) Super-Zoom (R) or just a knock-off? The way to distinguish them is pretty straightforward: did that box cost more or less than £400 ?
RFC3514 it's bigclive do you think he would buy a genuine apple accesory. Where is the fun in that
+RFC3514 --> The Genuine™ Apple® Super-Zoom© Box: now at your local Apple® Store for the unbelievably low price of £499.
This joke is so much better after the release in 2019 of the 1000 USD monitor stand. Absolutely mad.
LMBO
Neon bulb can be used too. It's a Beta/Gama detector. Bias the neon bulb to just the other side of "off". It's a 80s forest mims hack.
The slight downside of that circuit is that neons often contain a tiny amount of radioactive material in the electrodes to ensure they light reliably in dark environments.
apply radio-active glass balls to baby's rectums. I cannot stop crying with laughter, i'm going to need to stop soldering for a bit. Classic Clive.
ChaZ that one almost made me shoot beer out me nose haha!
Lol I was soldering when watching this I always do when watching Clive
@@dezmondfur6271 Ah ! Synchronized soldering. The newest sport at the Olympics.
Vaseline glass - The most typical colour of uranium glass is pale yellowish-green, which in the 1920s led to the nickname vaseline glass based on a perceived resemblance to the appearance of petroleum jelly as formulated and commercially sold at that time.
....and now you know :)
Vaseline glass milk jugs use to keep your milk nice and fresh for longer..or so they say.
And knowing makes it even more confusing!
@@Witheredgoogie Yes, and it also gave you a heathy dose of ionizing radiation. Ah, the wonders of the nuclear revolution.
Out of all english speaking Russians, the ratio of friendly people to trolls is about the same as the rest of the internet. I met some very cool dudes playing online games that I would still consider friends to this day. It's quite silly to get influenced by media calling a group of people evil when you can go online and talk to them directly, only to realize that they are exactly the same as you.
bami2 thats the power of media to spread false infomation in the name to spreading the truth
Exactly how the media demonizes anybody with view points or opinions that aren't extreme far left, calling everyone they disagree with Nazis and racists and all that crap, telling their followers to attack anyone who happens to have a different view point then theirs.
It will start a war very soon if they don't stop, or aren't forcibly stopped. And it's a war they will lose very quickly.
There's a kind English speaking Russian in one of my regular Twitch chats, my best 'chat buddy' is Russian. I have nothing bad to say. The media lies very much. I don't watch it. Learned to look more at people as just that, people, over the years.
“Take anything you see on television with a pinch of salt” you were dead on when you said that almost a decade ago 👌
The "Vaseline" name refers to the yellowish-green color, which is similar to the color of petroleum jelly.
That was one of my Favourite videos that you have done Clive. Keep up the great work. Nick.
the moment you said 'apple zoom' and pulled the box out i accidentally spat hot chocolate all over my bed -_-
nathan leather Now explain that to somebody who did not see you spilling chocolate...
8:45 well that statement hasn't aged well
Do you really think that ordinary people in Russia want the war? I think it's still true
I was just thinking about this..😄
Yeah, especially now with threats to UK and others.
For what it's worth, if you're still curious:
They're nicknamed "Vaseline glass" because the yellow-ish color of the marbles resembles early 1900s petroleum jelly.
All the beta should've been blocked by that; that means there's gamma coming off it. I'd put those mantles in a three inch thick lead box.
When Clive placed the thorium mantles next to the Geiger counter, it spiked from about 1.2 µSv to just under 5.6 µSv. As examples, the background dose received by an average person over one day is 10 µSv. Also, an airplane flight from New York to LA would equate to 40 µSv being absorbed by the body, and the average yearly dose a radiation worker must be limited to is 50 mSv. Furthermore, a fatal dose is generally considered to be between 4 to 8 Sv in one exposure. Finally, if one was unfortunate to have been standing next to the Chernobyl reactor core after the explosion and meltdown for about ten minutes, then one would have been 'hit' by a massive 50 Sv dose all at once.
thx for putting values into perspective.
If the radiation was much higher the mantles would probably glow without being hooked up to a gas supply.
There is no such thing as overkill; there is only 'open fire' and 'time to reload'.
The exposure rate on the device is probably supposed to be microsieverts per hour.
You've inspired me to buy one of those and some of the radioactive marbles and glass from the Czech republic I look forward to getting on that and experimenting thank you for being an inspiration
The GM tube you are working with can only detect gamma radiation even if other radiation is being given off. Other GM tubes can detect alphas or betas. This is why the aluminium only attenuated the radiation by a small amount. Also, the distance from the source (mantle) will be very significant.
Great video by the way. Thanks.
Really enjoy your channel, always informative, at times very funny.
Uranium gives off alpha particles. Also the vaseline glass term comes from the fact the most typical color of uranium glass is pale yellowish-green, which in the 1920s led to the nickname vaseline glass based on a perceived resemblance to the appearance of petroleum jelly
Not only Alpha.
Thorium 232 as used in gas mantles is predominantly a gamma emitter. It decays to Radium 228 which is a beta emitter. Thorium 230 is also present in gas mantles in trace amounts and is an alpha emitter. Th230 has a decay path that includes Radon gas. So basically, an old gas mantle will not only emit alpha, beta and gamma, it will also give off a radioactive gas.
Thorium-232 is primarily an alpha emitter.
I was hoping that you would put an ionizing smoke detector by the unit.
Thorium decay emits alpha particles as I understand it, but it decays to Radium and Radon which emit beta and gamma radiation, and that's what the geiger tube is detecting. So presumably that'd mean that gas mantles become more hazardous with age. If you open the bag Clive do it outdoors.
Given the half-life of thorium, I don't think the age of the sample is going to be terribly relevant. The daughter nucleides decay more rapidly than thorium so they generally won't accumulate.
Dusted off my netio Geiger-counter … reviewing your video.
I have many times walked into a thrift shop looking for old Green and Blue glass plates that are "Radio active" with my 1950s style counter. Fun stuff.
All natural uranium isotopes emit alpha particles. They have very low beta and gamma activity.
Thorium has the longest half-life of all the significantly radioactive elements, 14.05 billion years; it decays very slowly through alpha decay to radium-228, starting a decay chain named the thorium series that ends at stable lead-208.
I think depleted uranium is an alpha emitter, but it does decay into a few gamma and beta emitters. This is because uranium-238 decays directly to thorium-234, which with a half-life of 24 days decays to protactinium-234, which in turn decays in a matter of hours to the long-lived uranium-234. A quasi-steady state is therefore reached within a few multiples of 24 days.
Uranium-234 is actually so stable, it has near negligible radioactive danger, and is actually more of a chemical toxicity concern.
Uranium and thorium are both alpha emitters, but they also emit gamma. The proof off that for thorium is in the video here. Neither alpha nor gamma radiation can pass through aluminum,but gamma can, so the counts coming from thorium through the aluminum are gamma.
It's a frightening world we live in when a Geiger counter becomes an essential household item.
"Take anything you see on television with a pinch of salt."
Would that be Uranium salt? 😀
Hmmm, while Thorium itself is only mildly radioactive, and is an alpha emitter, which is blocked by paper, glass, metal et cetera, it's decay products include radon and radium which are much more dangerous. If you're getting a reading through the plastic bag and even through the aluminium plate, then that's not just Thorium you've got in the bag.
Thorium does NOT decay to radon.....it DOES decay to Thoron though.
Radon comes from Uranium(really from the Radium component of Natural Uranium).
Pure Uranium does not contain Radium, and thus no Radon.
And Radium comes from Uranium, NOT Thorium.
M. K. What the fuck is Thoron?
Thats.. Not an element.
Sorry, but Thoron? Thorium definitely decays to Radium, then Radon, Polonium and Lead. Here's a picture of the chain: en.wikipedia.org/wiki/Thorium#/media/File:Decay_Chain_Thorium.svg
@@Aslyuriel I am pretty sure he meant Sauron.
Hi Clive.
Uranium glass emits both beta and gamma. I tested a piece I recently bought with a sheet of paper between it and my geiger and the and it read the same, indicating beta + gamma at least. My GC isn't sensitive to Alpha. Then when I placed a folded aluminium sheet between the two did the reading go down, indicating gamma only.
That thorium mantel, if it emits gamma, then your dad's night stand would have not blocked it.
Very sorry to hear about your Dad, it is a thought though, were there many in the draw?
My uncle studied Thorium (Th232 specifically) for many years as a Nuclear Physicist for the purpose of providing us with energy instead of Uranium because of the abundance of Thorium and it's less dangerous. It makes little sense why we do not already use it because it essentially breaks down to the same Uranium isotope U233 once it absorbs a Neutron (you need a neutron source) U233 is the isotope in Uranium reactors all over the world!!!!
You should check Cat Litter and Toilets Bowls with your meter...the clay used to make Cat Litter and Toilets (at least in Canada & the USA) is slightly Radioactive (not dangerous, just a little above ambient)...
Every time I took a load of Cat Litter from Ontario to the USA (former Truck Driver), the Boarder Crossing would go nuts because my trailer set off the Radiation Sensors at the Customs Booth...
These counters only really detect Gamma as the tube itself will block out nearly all the Beta rays. As for alpha well that won't even get through the air let along the tube wall. Don't ingest Alpha sources though, then they are much more dangerous than Beta and Gamma.
I know this is a really old comment but should let you know that is incorrect about the tubes. The SBM20 variants are very sensitive to beta. I have used them extensively to detect both milder U-glass and pottery glazes. They are great for that. Also, alpha can travel about 1" through the air but cannot penetrate that tube wall - unlike beta and gamma. Got some vids on my channel but nothing as cool as Clive does. :)
@@nefariumxxx ( Looks at username... runs off to watch the your vids )
These are used mainly for detection of beta emitting contaminants
I’ve had Over a dozen packs of vintage lantern mantels in my vehicle glove box. The glove box sits between the driver and passenger seat. I do a lot of fishing and traveling, and I keep several Coleman lanterns in my truck toolbox and all of the extra packages of mantels in my glove box. I’ve spent at least 300 nights sleeping in my truck driver seat over the past 10 years. With my head literally inches from the lantern mantels. I have several Geiger counters, and the lantern mantels never occurred to me. However I recently checked them with my SBT10 and SBT11-A tubes… And indeed they are radioactive.
I reclined my driver seat and measured the exact distance of my head to the mantle’s, which varies between 9 and 14 inches depending on which way my head is turned. I do a lot of traveling… One winter in particular I slept in my truck every night for five months solid! Traveling looking for musical instruments and other interests… I’m just more comfortable in my truck than checking in and out of a hotel twice a day.
I’ve been traveling out of my vehicle part time for the past 13 years. And I’ve had those lantern mantels there almost the entire time. I Purchased a large box of mantels from a small town family owned hardware store that had been in business for 40 years. They were going out of business and about 15 years ago I purchased an entire box full of mantels. Probably a gross (144) but I’m not quite sure.
The glove box is at least an inch thick on all sides, made of leather, nylon, and plastics. Curious if I could pick up radiation damage with this prolonged exposure? When I get my new counter( and extremely sensitive tube) within the next few weeks… I will measure from the outside of the glove box and see if the radiation makes it through.
Would really appreciate any feedback. thanks for the great video
Thorium is an alpha and beta emitter. More of a risk of you ingested some. The glove box would probably block most of the radiation.
bigclivedotcom Damn… I’ll have to find another excuse for my decreased mental ability
I looked on the apple store, but I can't seem to find that zoom app.
The App Store doesn’t sell hardware.
It’s in the settings
Try an apple crate.
Joke has a whole new meaning now
A little ramble, as the video goes on:It's held at 300-ish volts, that is an SBM-20 Russian/Soviet tube.
Pretty much the benchmark tube for DIY/low-end counters.
The voltage is feedback-based, using an ADC on the controller and a dividier.
It's a boost converter feeding into a relatively(!) large cap.
Uranium is an alpha emitter, but the decay chain emits soft gamma that you're detecting.
Thorium is a gamma emitter.
I'm from Belarus, speak Russian, and I highly disagree with you on the "cool dudes" part. I've been consuming almost exclusively western content because I really dislike our segment of the interwebs.
Oh, and the little dinky iPhone devices are so insensitive they're absolutely useless and pretty much a scam.
+Spirit I reckon the iPhone detectors may be based on the blacked out photodiode circuit.
The schematic for this Geiger counter does not show voltage feedback circuitry. It seems to be based on a calibrated oscillator drive to the step-up circuit. So I'd be suspicious of its reliability at high count rates.
bigclivedotcom It's a resistor connected to the diode(BPW34, google it, it's quite a fun and easy project with it if you actually build a power supply for it) directly, then driven by "speaker" output and listened to by the microphone.
The sensitivity is so miniscule it's not going to work, ever.
I remember someone shoving it into an xray machine, that only raised the count to a measely "dangerous" and ~80CPM.
There's not enough power to make an oscillator.
"But their only mildly radioactive" *meter proceeds to start beeping rapidly*
+Tim Gomes Human beings are actually VERY mildly radioactive due to our dietary needs such as potassium, a tiny bit of which is radioactive.
I watch some videos that are Russian. There's some English in some videos. I don't know Russian very well. I know the Russian alphabet, so I can make out some words and speech, but the ones I watch are fantastic! Those Russians are gifted! Very passionate about what they do! I love it! And I'm from the US. Governments are often what give foreign people bad names.
I still have a tiny tin of Humbrol Luminous paint. Some of the paint is on the lip of the tin. I keep it in a garden shed on a high shelf but at night when you open the door there it is - GLOWING GREEN.
The new phosphorescent paints are called 'luminous' but need a light source to recharge them. This old Humbrol paint manages very well on it's own. I assume it's banned now. After the old Smiths dial factory was closed they found an area where the old paint tins had been dumped beyond safety limits. The soil I believe was put in drums and is now possibly at the bottom of the sea.
They might even be off the Isle of Man. Do you like sea food Bigclive? Does your beard give off a faint green glow in the dark ? Have you tried switching the light off in the toilet?
In regard to Russian video's on electronic kit. They look good, on average better than many. It's annoying when all you can find in 'English' is some dork mumbling a pathetic 'review' and plugging an amp into a crappy speaker and expecting you to subscribe.
Real Russian vodka, it goes down neat like a nectar from the God's. You won't find it in an off licence. People from cold countries have the warmest hearts. You are so right about Russians - englishrussia.com/ They are completely mad of course LOL.
Like someone else I know.
Yep, that paint has Radium and some sort of phosphor.
Generally, the phosphor degrades over time, due to Alpha bombardment and moisture, which is why most Radium painted items no longer glow.
Gas mantles sold in the EU are supposed to contain yttrium oxide instead of thorium oxide, but ones from China may still be thoriated. The problem with storing gas mantles is not the mild beta or gamma emission but rather the build-up of "thoron" which is actually Rn-220 a short-lived isotope of radon and a significant alpha emitter just like "normal" radon-222. A jar filled with thoriated gas mantles is a good source of thoron to demonstrate half-life in a school or university physics lab. Keep them outdoors if possible!
I live basically next to them drugi Russians and these tubes come by a pretty penny... not cheap.
A working area monitor costs as much as a brand new phone... But the Geiger counter is a useful tool I like having in my tool box and it is the one that I never want to hear buzzing except when I press the ~check~ button.
Should test the radiation that you get from a banana
+UnrealVideoDuke
He uses the banana differently.
It won't be measurable with a regular geiger counter. It's so low level that you'd need a lead cave and a scaler geiger counter or a gamma scintillator.
It's not measurable. I have tried it with a Victoreen CDV700.
I have some KI and KCl. I can measure those.
Background radiation is 12 CPM while with KCl, I think it was 20 CPM.
The radioactivity comes from K40 which is sometimes a beta- and sometimes a beta+ emitter.
He electrocuted the whole bunch.
A lot of people collect WW1-2 to 50s aircraft clocks and other stuff and don't know that those are very radioactive. Anything that has stuff that glows in the dark or at least used to glow and produced before 60s can be very dangerous. Aircraft/railroad equipment, watches/compasses, some switches etc. If you see slightly orange dots, letters, paint on clock hands etc - use Geiger counter. It's not radiation by itself that dangerous (but still dangerous) unless you keep those under your pillow or in your pants but radium paint which starts to fall off and you will inhale small particles causing massive amounts of alpha radiation to wreak havoc on your internal organs, which aren't protected by skin and clothing. One guy had a WW2 aircraft radio that was more radioactive than a truckload of those gas mantles.
Radium paint yes, it was even used on alarm clocks for a while. The 'orange dots' you're mention sound like the paint on old Fiestaware dinnerware, but it isn't used for self-illuminating paint :)
Excellent video... your comments on Russia are spot on also.
Another great video. I particularly like the zoom... I would also say that if the radiation can still be detected through aluminium, then what you have there is gamma radiation. I would be tempted to store those gas mantles in a lead container, if I were you.
most gamma radiation passes straight through you. highly ionising but harmless in low quantities.
wobblyboost It isn't, if it's passing through you, it's not damaging you. The damage occurs when you absorb it.
Luke Stanmore - Ionizing radiation does pass through: the trouble being that some of it may like to stay and have a 'look round' as it were. Especially if it hits denser tissue, like bone, or areas with a high density of blood vessels, like the liver, pancreas, thyroid, spleen, genitalia, etc. Ionizing radiation. Be afraid. Be very afraid.
I have a Geiger counter, I calibrate it using an old Westclox alarm clock circa 1950 , it almost goes off the scale due to the radium on the fingers. I don't keep the clock anywhere close.
And imagine that, people would have kept those a foot or so away from their head for maybe years (cumulatively) Cool as a radiation source, but not for actual intended purpose! Keep it the fuck away!
You can determine if those marbles are Alpha/Beta emitters, by placing a piece of thick card between them and the Geiger Counter.
If they're Alpha/Beta emitters, the count rate will drop significantly, whereas if they're Gamma emitters, there'll be no change in the count rate.
Geiger tubes cannot detect alpha particles
@@tfw8738 Are you sure?
From Wikipedia:-
"It is used for the detection of gamma radiation, X-rays, and *alpha* and beta particles."
@@BedsitBob huh, guess you were right. I learnt in school alpha particles couldn't be picked up on a Geiger counter
We used to use one of these but that looked more like a db meter when I was in a x-ray development workshop. Their physics guy taught me that a sievert equates to a joule, why do we need all these units that refers to the same ammount of energy? Anyway I renamed the calorie to Ragnar (Sievert is a name here) after this guy, he was really funny and a good teacher just like you clive.
+rimmersbryggeri "1 Gy is the deposit of a joule of radiation energy in a kg of matter or tissue." wikipedia.
Sievert is 1:1 gray for normal tissue and a coefficient for sensitive tissues, so it mostly reflects the damages it does to the body. (ex: 20 for breasts, Thyroid).
Also Alpha particles do more damages and have a high Sievert multiplier.
Hi big Clive great video's as usual ,are you going to have a Shot at making one of those photo cell Geiger counters hope you'll have a go .your channel is mint well done
Hello big Clive, the reason it's often called "Vaseline Glass" (ioxide diuranate form) is that the translucent lustre in some ornaments on the glass looks like Vaseline. The proportion usually varies from trace levels to about 2% uranium by weight, although some 20th-century pieces were made with up to 25% uranium.
This may interest you? : -
Estimates of the Radiation Exposures
A very detailed analysis of the radiation exposures due to uranium in glassware can be found in the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG 1717).
There are three principal radiation exposure pathways associated with Vaseline glass:
1. Exposure to the body from the gamma rays emitted by radionuclides in the glass.
Chemically processed uranium of the sort we are considering here consists of the following radionuclides: U-238, Th-234, Pa-234m, U-234, U-235 and Th-231. The principle gamma rays emitted by these nuclides would be 63 keV and 93 keV from Th-234 and 186 keV from U-235. NUREG-1717 estimated the following exposure rates from two different pieces of glass with 10% by weight uranium content:
Distance Drinking Glass Decorative Piece
1 foot 9 x 10-4 mrem/hr 1.8 x 10-3 mrem/hr
3 feet 1 x 10-4 mrem/hr 2 x 10-4 mrem/hr
6 feet 2.5 x 10-5 mrem/hr 5 x 10-5 mrem/hr
For comparison, the background exposure rate due to gamma rays is approximately 1 x 10-2 mrem/hr.
2. Exposure to the hands from the beta particles emitted by radionuclides in the glass
The aforementioned NUREG-1717 also calculated the beta dose rates at a depth of 7 mg/cm2 (i.e., the nominal depth of the germinal layer of the skin) as well as the estimated effective dose equivalent. It was assumed that the source was a 10 inch diameter plate with a 10 % by weight uranium content.
Distance Dose Rate Effective Dose Equivalent Rate
Contact 27 mrad/hr 0.0027 mrem/hr
1 foot 1.1 mrad/hr 0.0027 mrem/hr
3 feet 0.095 mrad/hr 4.7 x 10-4 mrem/hr
The ratio between the effective dose equivalent rate and dose rates vary with distance because the further away from the source, the greater the area of skin that was exposed.
3. Ingestion of uranium that has leached into food that has been in contact with the glass
Landa and Councell evaluated the leaching of uranium into different solutions over a 24 hour period. The glassware they used was designed to hold liquids (e.g., drinking glasses). They determined that the average resulting concentrations of uranium were 0.052 ug/liter (1.7 x 10-11 uCi/ml) for water and 5.9 ug/liter (2 x 10-9 uCi/ml) for acetic acid. The highest measured concentrations were 0.63 ug/liter (2.1 x 10-10 uCi/ml) in water and 30.1 ug/liter (1 x 10-8 uCi/ml) in acetic acid. They noted that less uranium would leach into solution when the experiment was repeated. The presumed explanation is that less and less leachable uranium becomes available.
After estimating the effective dose equivalents for a variety of potential exposure pathways, NUREG-1717 concluded that the highest doses would be to the personnel involved in the transportation of the glassware from a manufacturer to a truck distribution center. This maximum estimated dose, 4 mrem/year, is approximately 1 to 2 % of the average American’s annual radiation exposure.
Oh that's very cool Clive: I've always had a fascination about Geiger counter's and now I want one !! But what I thought was really fascinating about your talk is that new telephoto lens for the iPad that seems to work so well. PLEASE can you tell me where you got and was it over 100 dollars in price. As always, good stuff and thanks for the demo.
Apple super active zoom feature was brilliant, made me laugh out loud
I always wanted a Geiger counter, being that I live within a few miles of a Nuclear Power Plant. I kinda want to drive by on my bike and see if I can find any difference between here and the plant (of course not on the actual grounds of operation, but definitely close enough to be well within Evac Zone 1).
Very nice! Uranium-238, Uranium-235, and Uranium-234 are alpha emitters. So is Thorium-232. Their many decay daughters also emit alpha, beta, and characteristic gamma rays. That rare earth glow powder (if I had to guess is europium-based) gave your Geiger counter a noticeable increase in counts when you put it close to the tube. It's possible that the REE glow powder could have some traces of Thorium when it was processed from Monazite sand (maybe), or other minerals. Maybe some trace REE isotopes? Gamma ray spectroscopy would let you what isotopes are present. Interesting! Thanks!
Vaseline glass got it's name from it's pale yellowish green colour that resembled the original colour of vaseline. I had an aunt that used to collect it. She lived to be 94!
I don't know if anyone mentioned it yet, but most mantles (Coleman, etc.) on the market now, contain Yttrium instead of Thorium and won't have any effect on a Geiger counter.
Interesting video Clive.🤔
I power my SBM20 using a photo flash transformer whose primary is pulsed by an mc34063 which gets its feedback from the HV+ via 2 hv zeners of 200V each.
Works like a charm.
Do those Bullfinch Mantles (as seen at 5:10) come in different sizes and could they be used to encapsulate one's scrotal sack as a form of birth control?
Yes, I'm late to the party. Can you find an antique clock that has radium painted hands and numerals? Westclock made then for many years, they can be found on ebay and in antique stores ( the ebay offerings are cheaper even with shipping) the radium on them has a halflife of about 40,000 years and it would make your counter do mucho clicking.
There are a lot of interesting technical English-speaking Russian TH-cam channels. I found one a few weeks ago that talked about the history of the development of Russian Soviet-era computers, showing a few different models and processors and the like. It was very interesting. There were lots of knockoff clones of Intel chips of course, but they also did develop their own. Science in general had an... interesting... time during the Soviet era. You wouldn't think that politics would affect it too much, but it really had a big influence on some parts. Biology was a big one. They opposed evolution on the grounds that it was a capitalist ideology, for instance. I've got an interesting book called 'The Perversion of Knowledge' that was written by a Russian scientist who lived through the time period and became a dissident opposing the Communist meddling (and the horrifying human experimentation).
If you're going to do any more Geiger counter fiddling for videos, might I suggest breaking open an Americium-containing smoke detector? Or, if you can find one, a device with the old school Uranium-bearing glow-in-the-dark paint? I had a clock with such paint displaying its numbers as a child but didn't realize what it was until much later. Not sure what happened to it or I'd offer to send it along.
I'm glad the soviets did clone our computer chips. I've got a few Russian PIO chips in my old pinball machines.
Kreosan is a crazy Russian channel with English translation- well worth watching their antics!!
Thorium's primary decay is through alpha radiation, but it's a large particle, and you'd pretty much have to inhale radioactive dust to cause any harm. Uranium primarily decays into Thorium through the same method.
2:00 So if I accidentally touch the GM tube holder electrodes, I won’t even notice it? That’s a relief!
Don't know how many times I got that mantle dust in my mouth from using Coleman lanterns for work because we had no lights to work by ! The new material being used produces a very yellow light
We have one of those old gas mantles sitting in a draw by the kitchen... Makes you think. Plus what else is in our lives that we have no idea about.
Thorium mantles are quite spicy. I have one of the green dyed ones. It saturates my counter. I keep my samples in a steel steetie can on my bedside cabinet. The radiation still leaks through and that's with the samples wrapped in 4 layers of BACO-Foil and inside a steel can. Looks like your counter uses an SBM-20 tube like mine. Only good for beta/Gamma only. Check out an old fire alarm. Thay generally use an Americium pellet (Alpha emitter) and you counter won't detect it.... or if it does, it will barely detect anything. For Alpha you need a different tube with a mica window and a higher voltage.
@3:20 the Vaseline reference was due to its somewhat similar pale-yellow coloration of Uranium glass....though coloration is highly dependent on the oxidation state of the Uranium used.
If you have a checkbox with a 100M position, that might be high enough to use as a ballast with a DC ammeter so you can check the Geiger tube voltage.
Nothing like that first microsievert of the evening :-)
I wonder how vacuum valves would work as radiation sources considering some of the cathodes and filaments were doped with thorium.
I think that the plastic bag around the marbles with block any alpha from being detected by the geiger
The mantles are impregnated with thorium oxide. When you first put the mantle in use, the organic material burns out and the thorium oxide is all that remains. And there comes the crucial detail. Thorium oxide melting point is 3390 degrees C and the boiling point about 4400 degrees C. Pure tungsten melting point is just 3422 degrees. To operate plain tungsten anywhere near 3000 requires inert gas environment, while thorium oxide is already “burnt” and can be operated as those mantles without other concerns than vibration and shock.
+Pellervo Kaskinen:
It isn't because of the melting point or boiling point that ThO2 is used.
ThO2 exhibits a phenomenon called candoluminescence (or is it candeluminescence).
It emits more visible light than some other materials. This is because instead of emitting in the infrared region, some of the energy is stored and emitted in the yellow region.
If you want, buy some chalk or get some from your backyard. It is CaCO3. Heat it with a torch strongly and it will convert to CaO which is candoluminescent. Do it in the dark. Compare it with heating some other piece of rock or brick. You can easily tell the difference.
This is where the term "being in the lime light" came from. They heated CaO with some torch in theaters. They call CaO or Ca(OH)2 lime (limescale?, lime water? calcium and lime?) in the old days for some reason.
louis tournas : Interesting... Never heard of those details. Although another lamp called Nernst lamp is based on the chalk or more likely magnesium oxide. And makes me speculate that the oxide is the key. After all, burning magnesium was the old source of bright light for photographers. The common item for all these seems to be oxygen. Hmmm...
How dangerous are those mantels and marbles. Enough to get radiation sickness?
Tritium emission will be stopped totally by glass. That is why they are safe in exit signs.
I have some modern mantles ( made in China) and they are also radioactive, though they have lower levels of Thorium. Must take apart an old ionisation smoke detector and see how active the tiny blob inside is.
The source in an ionisation smoke detector is Americium 241-its primarily an Alpha emitter, so a standard metal or glass wall GM tube won't detect much...A mica window GM tube or other Alpha detector will detect the Alpha-lots of it.
A metal or glass GM tube will detect a SLIGHT bit of radiation from it though-even though it's mostly an Alpha emitter, it emits a small amount of low energy Gamma, mostly at 59.5 KeV.
This is very low energy, and does not travel far, so no substantial hazard.
I miss those thorium mantels, they gave off the brightest light. Modern mantels are dim by comparison and are much more fragile compared to the old thorium ones.
Vaseline glass was called that because of its cloudy appearance that looked like smeared Vaseline.
When he starts the video with :
Radioactive fun with Bigclive - you know it's going to be fun ☺
Lol it was a constant beeeeeep with the thorium mantle. That's comforting... 😂😂😂
Modern digital x-ray imaging panels are usually amorphous silicon panels. I believe they detect beta and probably alpha radiation pretty well on their own. I know that for radiotherapy they use a copper sheet or something similar as a scintillator to convert a few xray photons into electrons for the silicon panels, to get an image. Long story short, would be very interesting to try some kind of scintillator in front of a silicon photodiode to see what readings you get.
Everyone knows a Geiger counter clicks not beeps. Is it possible to modify the circuit or the speaker to hear a proper click?
You should have opened up a smoke detector for the Americium!
Given the 300V across the tube, could this thing give you a bit of a tingle?
+Chlorate It could give a zap from the high voltage supply's capacitor.
Get a 9volt strobe light, the type used in alarm systems etc.
Remove the bulb, connect it to a battery then put your fingers on the connections for the bulb :D
Trust me, 300V is more than a tingle hehe..
A fun project might be to build a true randon mumber generator based on the timing of the blips. (E.g., measure intervals to the nearest millisecond, and take a digit from the middle of each result.
Brasil nuts will also set off Geiger counters, due to the Selenium in them.
It is based around the Russian tube СБМ-20 which is for hard beta and gamma rays. Which means the tube itself stops the low energy electrons? But I wouldn't trust it with any beta at all.
Hi Clive, There is Thorium in some tig welding rods. I will run my (Maplin) counter over some.
I just tried a box of standard welding rods and didn't see a significant change in ambient level. I'll try some others in the future though.
No it is only the Tig electrodes ( I should have said electrodes)
Just checked, they are thoriated Tungsten and the count is around 0.15/0.17 mills on my counter.
Background here is around 0.1/0.12. Nowhere near your mantles I have some somewhere for my Tilley lamps. Keep up the good work!
That GM tube looks like an SBM20, made in Ukraine afaik. Similarly to the Japan/Fukushima thing, Geiger counters became popular in Ukraine after the Chernobyl disaster.
I bought a cheap Ukraine built GC a while back and at some point dropped it thus finding out the hard way that those tough looking brass tubes contain a fragile glass tube, it made a heart sinkingly jingly jangly sound when shaken :-(
Much to my delight, I found out that replacement SBM20s are dirt cheap! So, £10 and an ebay visit later got my GC working again!
Thumbs up.
I bought this unit from a Japanese seller right after Fukushima. There's nothing quite like a nuclear accident to boost the sale of Geiger counters.
LOL yep :-) Ho hum nuclear shite ach well, nighty night!
Now that's something i'm getting, where did you get yours? Do you need to get the tube separately? Thank you, that was interesting! What about Tritium vials?
I got this one from a seller on ebay. Tritium is a low energy beta particle emitter. I'm not sure much radiation would escape through the glass and plastic housing.
As a former angler, I'd be interested to see what reading you'd get from the 'isotope' glow-in-the-dark bite indicators that are used. I've heard they have a half-life of twenty years which sounds fairly weak but I'll have to see if I still have any around that I can send you...
+tony sansom They sound like tritium tubes which will not emit detectable radiation through their glass vial.
Super apple zoom feature! ^~^
I'm dying!!
What do you think about the Smart Geiger Nuclear Radiation Detector's sold on Ebay? Are they any good?
Where did you get the meter you using in this video? Is that a self-build thingy from Ebay?
They are called Vaseline glass due to the color being similar to the petroleum jelly back then
And thorium kinda sucks as it decays into both alpha, beta and gamma radiation.
Excellent video. This is what I really want to get into. Yes, there are some awesome Russian hacker dudes.
Do you suppose an optocoupler would work without the emitter being powered? Since you mentioned a photo diode it's got me curious...
How did Van Allen measure the radiation when he was surveying the radiation surrounding the earth? I read somewhere that scientists were puzzled as the geiger counter would hit a certain point of readings and then shut down, the assumption was that there was a radiation free zone in the outer layer of the radiation belt, what in fact was happening was the sensor was being saturated and reading zero. Does your counter reach a saturation point where it stops reading radiation?
+Gromitdog1 I've not actually found a source of enough radiation to do that yet. But I watched video of the same model being used in Fukushima and it was certainly managing high count rates.
+Gromitdog1 The first probe which measured radioactivity in Earth's orbit did that, yes. Hundreds of later missions were better equipped.
Gromitdog1 I have a similar counter that use when playing with radioactive stuff. When I hit it with my home made x-ray machine, it goes off the charts then freezes. If I wanted to get accurate measurements, I would need to use one of my survey meters with an ionization chamber. It can measure tremendously higher radiation than the Geiger Muller tube.
Questions arise. if this device is sensitive to beta and not just to gama. Beta comes from potassium, it can be bought as fertilizers for the village economy and gardens, there about 46% of potassium, and in potassium chloride fertilizer are more potassium%! Just do not get it clear that it measures. It would be nice to check
super apply zoom feature XD
Hi Clive, i have lots of these vaseline/uranium marbles wich i also played with as a kid, i have them in a wooden cabinet besides my bed do you think the woods stops the radiation?
Thanks!
+Harry de Vokone Yes .