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ArcticMyst Security by Avery

☢ My Radioactive collections ☢

Benm

Benm

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You should realize that gammas and x-rays are exactly the same type of radiation (i.e. photons, like light, radiowaves etc). Strictly they are called gamma's if they come from the nucleus itself and x-rays if they come from the electrons (brehmstrahlung for example).

Tritium itself does not produce gamma rays when it decays, but if you detect any, they will probably be x-rays from any material absorbing the emitted electron. The energy is so low though that the x-rays produced by that would appear to come from something like an x-ray tube.
 





Benm

Benm

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Yes, it is radioactive with a half life of 12 years, but on decay it only produces an electron (beta radiation) and a neutrino, no gamma ray. The electron has a kinetic enery of 18 keV or so, and cannot produce an x-ray with more energy than that regardless of what it hits.

This makes tritium perfectly safe as long as you don't ingest it.

If you get tritium labeled compounds you can detect their activity perfectly well when you put them into scintillation solution and count the flashes of light.

Those little lights containing tritium gas are very safe. Even if you manage to break them and inhale some of the tritium there is no serious health risk - most of it will simply be exhaled, and whatever little is absorbed will make its way out quite quickly as our metabolism does not process hydrogen gas (or its isotopes).
 
Flaminpyro

Flaminpyro

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Well then would it be safe to store anything in this jar that may be eaten later :whistle:

And will it really keep the bugs out because it radioactive :banned:


3x6" KRYPTONYTE glass jar under black light, in normal light the glass is yellow.
 
Pi R Squared

Pi R Squared

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About the food and critters I am not so sure. Did anyone here see the 1957 movie "Beginning of the End" staring Peter Graves? :eek:


Alan
 
Seoul_lasers

Seoul_lasers

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Benm said:
If he is in seoul hy might find some a bit up north, say where the north koreans did nuclear tests ;)

I doubt you'll find much of it otherwise. There are very limited practical uses for the stuff, and due to its biological dangers other isotopes are preferred when possible at all. It's only produced in nuclear fission reactors and -bombs, and even used to date things being produced before or after the WW2 atomic bomb (tests).
Click to expand...

Nope I live in Canada right now. I repatriated in late 2014. yes I am still looking for a 1-5uCi Cs137 source for the spectrometer I built.
:beer:

BTW, where did the Sr90 source come from?
 
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TheMaxii2007

TheMaxii2007

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My DP-5V Geiger counter - Strontium-90 check source

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Seoul_lasers

Seoul_lasers

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Those check sources are strictly regulated in most countries. The activity of the Sr90 check source on those meters is enough to get it confiscated in the mail by customs and a hefty fine for undocumented radioactive material.
I believe in some cases the sources were completely removed altogether by Russia as they were far too hazardous
to be left in the decommissioned equipment.

Several of these survey meters have Check sources in the 350uCi range making them actually dangerous to handle. (esp. in ion chamber detectors)

Sr90 is also a bone seeker so any amount of material the makes it's way out of the sealed environment is a bio-accumlative.

It is also a wise idea to not keep Sr90 sources in a glass container as doing so creates Bremsstrahlung radiation from excitation of the Si02. The result is a secondary emission of "x-rays" ~ I'm using the term x-rays here loosely.
 
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Benm

Benm

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Wow... that's one annoying geiger counter that goes into alarm mode on 0.2 uSv/hr!

You should be careful with that strontium-90 source though, especially from inhaling or ingesting any dust that comes off of it (not sure how well sealed it is).

As for bremstrahlung: it would be better to keep it in a polycarbonate case with a thicker wall. Not that the activity of that little piece is so high it would pose an actual health risk, but it will leak some radiation through the glass, and at 500 keV beta radiation inducing it probably through a thin metal case as well.

The produced x-rays will not travel very far in air, but don't put the box under your bed or something like that.

As for x-ray versus gamma radiation: it is exactly the same (i.e. photons), but x-rays originate from electrons and gamma radiation originates in the nucleus. Strictly speaking i'd say bremsstrahlung should be classified as x-ray since it comes from electrons, albeit not the ones normally bound to the nucleus they 'belong to'.
 
paul1598419

paul1598419

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My understanding of Bremsstrahlung is electrons that scatter at protons or in the field of a nucleus. X-rays are produced by electrons striking a metal collector. That is kind of the way I look at the difference.
 
Benm

Benm

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The electrons do nothing to the nuclei of the materials the induce bremsstrahlung into. What happens is that the electrons are attracted to the nuclei, making them change direction, and accelerated electrical charges emit photons. This is not unlike what happens in an x-ray tube:

electrons at speed hit a metal target, making them suddenly decellerate , resulting in the emission of photons.

There is no practical implication though, x-rays and gammas of equal energy are -exactly- the same thing, and hence require the same precautions, or suit the same applications if you like.

Higher energy photons tend to be of gamma origin, but that is more a matter of practical application. You can build x-ray tubes only to some voltage limit, so a 10 MeV photon is not that likely to be produced from an x-ray tube unless it operated on a 10 megavolt power supply.

Then again this doesn't really matter since at such energies you'll get electron-positron pairs produced.
 
paul1598419

paul1598419

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I never said that the protons or nucleus was effected. I know that the photons are emitted when the electron is accelerated or decelerated. Actually, collector is the wrong term. I should have said a target. You can get X radiation produced when, for instance, a metal such as Molybdenum, has a high energy electron fired at it and dislodges an electron from the K shell producing K alpha and K beta photons. These are much higher in energy than a 1 angstrom X-ray.
 
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Seoul_lasers

Seoul_lasers

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Benm said:
Wow... that's one annoying geiger counter that goes into alarm mode on 0.2 uSv/hr!

You should be careful with that strontium-90 source though, especially from inhaling or ingesting any dust that comes off of it (not sure how well sealed it is).

As for bremstrahlung: it would be better to keep it in a polycarbonate case with a thicker wall. Not that the activity of that little piece is so high it would pose an actual health risk, but it will leak some radiation through the glass, and at 500 keV beta radiation inducing it probably through a thin metal case as well.

The produced x-rays will not travel very far in air, but don't put the box under your bed or something like that.

As for x-ray versus gamma radiation: it is exactly the same (i.e. photons), but x-rays originate from electrons and gamma radiation originates in the nucleus. Strictly speaking i'd say bremsstrahlung should be classified as x-ray since it comes from electrons, albeit not the ones normally bound to the nucleus they 'belong to'.
Click to expand...

Actually it is basic Radiation safety in industry with strong beta emitters never to put them into glass containers because of x-rays (excitation by electron emission). There have been serious burns with larger sources.
You can accumulate a very significant dose over time from the secondary emission alone.
Those russian radiac sets had some very powerful Sr90 sources in them. ***While most of them are half lifed by now, they are still potentially hazardous..
Some sealed others NOT so much.
Please please store them in plastic ie) P.E. or polypropylene. Use gloves and forceps to handle them if you need to.
 
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Benm

Benm

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I wouldn't count on age to save you in any case - sure it has a half life of 29 years, but that means after 29 years it's still half as bad as it was when fresh.

Industry best practice for beta sources is shielding using plexiglass (polycarbonate, or some other material made up off low atomic mass elements like carbon, hydrogen, oxygen and nitrogen).

As for the effects of the bremsstrahlung it's best keep your distance. Air will absorb some of it, but more importantly your exposure drops by about the cube of the distance from a point source.

The metal box will do little good for that: to drop gamma/xray radiation of decent energy by half, you'll need about 1 cm of lead. A box of equal mass made out of perspex will be a much better shield, and there is no need for the glas vial at all.

You can test this quite easily if you have beta source: see what the reading on a geiger counter is 10 cm from that source, comparing no shielding, a pane of glass and a pane of plastic of equal mass/cm2 to that glass.
 
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