Can Radiation Be Seen When Contaminated?

[roy2008]

if someone accidentally came into contact with radioactive materials-or a container of radioactive material and they became contaminated-would they be able to see the contamination on their skin? I guess what Imsaying is if I don't see a metal or powder on my hands for example, then does that mean I have not been contaminated? would even an unseen fleck of radioactive dust harm people?

 

[Mech_Engineer]

if someone accidentally came into contact with radioactive materials-or a container of radioactive material and they became contaminated-would they be able to see the contamination on their skin? I guess what Imsaying is if I don't see a metal or powder on my hands for example, then does that mean I have not been contaminated? would even an unseen fleck of radioactive dust harm people?

Almost all inadvertant radiation contamination that results in a worker taking the radioactive material home is because they could not see it and didn't check with a detector.

In short, it is very unlikely your would be able to visibly see if you have been contaminated, the only sure-fire way to test is with a radiation detector. And yes, even very small amounts of radioactive material can be harmful, especially if ingested.

 

[gmax137]

Mech Engineer said
"Almost all inadvertant radiation contamination that results in a worker taking the radioactive material home is because they could not see it and didn't check with a detector."

Do you have any documented cases of this? What sort of facilities was the worker from? I've been working in nuclear power plants for a long time and I don't think I have ever heard of anyone doing this. Seems unlikely, especially with the portal monitors now in use (the whole point of these devices is to eliminate sloppy frisking). And if it did happen, how was it eventually discovered?

 

[russ_watters]

I guess what Imsaying is if I don't see a metal or powder on my hands for example, then does that mean I have not been contaminated?

Where do you work? Is it even possible for you to be contaminated?

would even an unseen fleck of radioactive dust harm people?

Potentially yes, but where would someone get something like that?

Unless you work in a place that provides you with a radiation exposure badge, you don't have a real chance of being contaminated.

Since you realize your fear is irrational, you should know that the answer to most of your questions is pretty much the same...

 

[russ_watters]

Almost all inadvertant radiation contamination that results in a worker taking the radioactive material home is because they could not see it and didn't check with a detector.

In short, it is very unlikely your would be able to visibly see if you have been contaminated, the only sure-fire way to test is with a radiation detector. And yes, even very small amounts of radioactive material can be harmful, especially if ingested.

Heck, radon was discovered when someone inadvertently brought it to work!

 

[Mech_Engineer]

Do you have any documented cases of this? What sort of facilities was the worker from?

Such accidents do rarely happen in laboratory settings (universities, national labs, private businesses) when people get lazy or indifferent. I work for a Department of Energy contractor, and workers receive extensive training on this subject if working in radiation areas.

I'm not sure that I'm allowed to point to specific incidents, but the Nuclear Regulatory Commission keeps publically-available "Event Notification Reports" on its website which you could look through if you're curious.

http://www.nrc.gov/reading-rm/doc-collections/event-status/event/

 

[QuantumPion]

Astronauts on the moon reported seeing flashes in their eyes, even with their eye lids closed. This was caused by high-energy cosmic radiation directly activating the chemical receptors or neurons in the eye.

If you were contaminated with a hot particle (a tiny but very radioactive mote of dust, common in some areas of nuclear power plants) on your skin, the area of skin may become red and irritated.

Photography film exposed to radiation will show spots when developed (this was how radiation was originally discovered!)

Also, digital video cameras exposed to high levels of radiation will display spots that looks like static or white noise (similar effect to astronauts, the radiation causes a voltage signal on the image sensor).

Finally, you can directly see the effect of radiation if you make your own cloud chamber. A cloud chamber is a sealed box filled with super-saturated alcohol vapor if I recall correctly. When a high energy charged particle passes through, it ionizes the alcohol molecules in its path, causing them to condensate and leave a visible trail.

Oh yes, I forgot the most striking example! Cerenkov light, which causes nuclear reactors in water to glow blue, is caused by beta particles (high energy radiation) passing through water.

 

[vanesch]

Oh yes, I forgot the most striking example! Cerenkov light, which causes nuclear reactors in water to glow blue, is caused by beta particles (high energy radiation) passing through water.

The point is, if you SEE Cherenkov radiation being given off by, say, your elbow, then I think the best thing you can do is quickly subscribe to a life insurance for your family... and not go home

 

[Naty1]

Typical radioactivity is alpha, beta and gamma radiation..there are others. A sheet of paper will stop the first, a sheet of metal the second, and some thickness of lead to stop the most potentent gamma. It would be unusual to see any radioactive material itself, but in the fallout from a nuclear bomb for example, radioactive material would be mixed in dust, the dust likely radioactive as well, and in those quantities likely visible. Such dust contamination on the skin can be mostly washed/rinsed off and clothes disposed...Inhaled radioactivity is potentially much more dangerous as there is no practical way to eliminate it from the body.

If you wear a radiation badge outdoors in sunlight, radioactivity can be recorded...An example of nuclear power plant workers being contaminated would be Chernoyble...Cooling water from a nuclear power plant might also become radioac tive...anybody know??...so if that leaked and somebody got wet, it would be visible in a sense..

The point is contamination has no visible signs...a spec of dust lands on you in a nuclear environment, you can't tell by "feel" or other senses if its dangerous or not...that depends in part of the strongth and half life of the material...

In nuclear medicene, for example, workers must be very careful, yet patients can be injected becuase the level of radiation is low and the half life just a some hours so in a week there is barely evidence.

Oh, and don't forget, visible light is radiation, and so is all electromagnetic radiation fopr that matter...

 

[vanesch]

Typical radioactivity is alpha, beta and gamma radiation..there are others. A sheet of paper will stop the first, a sheet of metal the second, and some thickness of lead to stop the most potentent gamma. It would be unusual to see any radioactive material itself, but in the fallout from a nuclear bomb for example, radioactive material would be mixed in dust, the dust likely radioactive as well, and in those quantities likely visible. Such dust contamination on the skin can be mostly washed/rinsed off and clothes disposed...Inhaled radioactivity is potentially much more dangerous as there is no practical way to eliminate it from the body.

I thought the OP wanted to know if we could see radioactive phenomena themselves, not just the stuff that is radioactive. After all, you can see a laboratory source, so you "see" the source, right ? But you don't see the radiation. By the time you see it, you're already long deadly irradiated, because the levels of radiation that are necessary to produce clearly visible luminous effects are very high.

If you wear a radiation badge outdoors in sunlight, radioactivity can be recorded...

Mmm, if the sunlight affects your badge, then that's probably an error of your badge. Sunlight is non-ionising radiation for most part.

An example of nuclear power plant workers being contaminated would be Chernoyble...Cooling water from a nuclear power plant might also become radioac tive...anybody know??...so if that leaked and somebody got wet, it would be visible in a sense..

Again, you would see the material manifestation of what might (or might not) be a radioactive source, but you wouldn't see the radioactive phenomena themselves. If nobody told you it was contaminated water, by just looking at it you wouldn't see the difference with just ordinary water.

However, radioactive phenomena are easily detected with instruments. Much more so than, say, biological contamination.

 

[mgb_phys]

I thought the OP wanted to know if we could see radioactive phenomena themselves, not just the stuff that is radioactive.

The OP has several other posts where they explain a phobia about being in contact with radioactive sources - they were asking if they can see if something is contaminated, presumably by some sort of glow.

 

[theallknower]

if someone accidentally came into contact with radioactive materials-or a container of radioactive material and they became contaminated-would they be able to see the contamination on their skin?

well,I gues that having so many eruptions on your skin that you allmost look skinless is a prety visible efect...not to mention other signs like hemoragia...but this is at a relative high energy radiation...for a few thousand dolars you can buy yourself a chemistry elemental set,including a bit of uranium...I gues that dosn't hurt at all,because it comes with protection

 

[theallknower]

And yes, even very small amounts of radioactive material can be harmful, especially if ingested.

why would you ingest something radioactive?
I don't see ANY scenario when someone ingests an uranium pill or contaminated water...exept mabey for suicids

 

[russ_watters]

why would you ingest something radioactive?
I don't see ANY scenario when someone ingests an uranium pill or contaminated water...exept mabey for suicids

Once it's on your skin, it can easily get to your nose or mouth.

 

[Xnn]

In nuclear medicene, for example, workers must be very careful, yet patients can be injected becuase the level of radiation is low and the half life just a some hours so in a week there is barely evidence.

Actually, I know a guy that received a medical injection and was told by the medical authorities that it was short lived and would be gone in a few days. Very re-assuring.

We both work at a Nuclear plant, and go thru radiation detector portals every day.
No surprise he sets it off on the first day back to work.

A week later and he is still setting off the portal monitors.

A month later and he is still setting off the portal monitors.

2 months later and he is still setting off the portal monitors.

It wasn't until 3 months, that he was able to exit without setting them off!

Don't remember the isotope, but it was some type of radioactive vitamin (B3 maybe).

 

[mgb_phys]

Probably more a testament to how sensitive you can make radiation detectors.

It's like the media scare stories about finding contamination of chemical X in drinking water - that come out every time the water monitoring dept gets a new instrument!

 

[Morbius]

if someone accidentally came into contact with radioactive materials-or a container of radioactive material and they became contaminated-would they be able to see the contamination on their skin? I guess what Imsaying is if I don't see a metal or powder on my hands for example, then does that mean I have not been contaminated? would even an unseen fleck of radioactive dust harm people?

roy2008,

First - radioactivity is NOT "contagious" - just because you come in contact with radioactive material
doesn't mean that YOU become radioactive. You don't get "contaminated" just because you get "near"
some radioactive material.

Now if; as you postulate above; there is a radioactive powder that you come in contact with - and
some of that powder STICKS to you - THEN you are "contaminated" to the extent that you now have
some powder on you and that powder is radioactive - you are now radioactive.

However, I don't know ANY nuclear lab or facility that would EVER allow what you state above to
happen. For example, there are cases where radioactive material is handled in powdered form - but
NEVER just out in the open. Such an operation will take place ONLY in a "glove box":

http://en.wikipedia.org/wiki/File:Glovebox.jpg

The inside of the box is isolated from the rest of the room. The gloves are hanging out the front
"inside out". When a worker is going to use the glove box - they put their hands in the gloves and
turn them right side out - so their gloved hands and arms are within the box - and they can safely
handle radioactive powders like Plutonium for instance. The radiation from the Plutonium is alpha
radiation that can't penetrate the gloves. The outside of the gloves may get Plutonium powder on them;
but your hands are on the inside of the glove - so you don't pick up any of the powder.

If you are going to handle a substance that emits more penetrating radiation, like gamma; then that
would be done in a "hot cell" with "master-slave" manipulators:

http://www.centres.com/nuclear/manip/models/modghd.htm

The worker holds a the controls in their hands - and the motions of the operator's hands are mimicked
by the "claw" on the other end of the manipulator. One side of the manipulator goes inside the "hot cell"
with the radioactive material - and the operator's side is outside the "hot cell" where the operator can be
shielded from the radiation by the shielding walls of the cell as in the drawing under the word "Dimensions"
in the above link. The operator looks in through a thick glass window as seen in the center of the
shield wall.

Dr. Gregory Greenman
Physicist

 

[Mentallic]

Radiation can't be seen? Homer Simpson would say otherwise

First - radioactivity is NOT "contagious" - just because you come in contact with radioactive material
doesn't mean that YOU become radioactive. You don't get "contaminated" just because you get "near"
some radioactive material.

Now if; as you postulate above; there is a radioactive powder that you come in contact with - and
some of that powder STICKS to you - THEN you are "contaminated" to the extent that you now have
some powder on you and that powder is radioactive - you are now radioactive.

In the (French?) movie 'Pu 237' a nuclear scientist working in a nuclear power plant was exposed to lethal doses of radiative material. Now even though he was washed down thoroughly, the man states in the movie that he couldn't stay near his family for long because of the radiation he was emitting. This contradicts your statement since he wouldn't have had any radiative materials on him. Is this foul play by the movie producers or is it possible?

 

[mgb_phys]

Leaving aside wether Pu237 is a likely candidate (it's a very short lived gamma emmiter isn't it?)

You could absorb some of the parent nucleid through your skin (again Pu is very insoluble so not likely) you would then become radioactive. this is the major radiation risk - especially with elements that are concentrated in your body like ceasium, calcium, carbon.

Or an intense enough radiation could induce radioactivity in elements already in your body by converting them into radioactive forms. This mostly happens with heavier elements and I doubt that you could become significantly radioactive by this mechanism without receiving a seriously lethal dose yourself.

 

[vanesch]

Accidents can happen, but they are rare. There are two kinds of accidents:
- "contamination" accidents
- irradiation accidents.

If you are *irradiated* then you can be lethally affected and die of radiation sickness in the coming days, weeks or months, but you are not a radiation hazard yourself.

For instance, the three operators which made the mistake at the Tokai Mura plant in 1999
(see http://en.wikipedia.org/wiki/Tokaimura_nuclear_accident for some info) made by accident a "nuclear reactor in a vessel" (that's a criticality accident), and got very very seriously irradiated (some died), but they were not a radioactive hazard themselves. During the few seconds of exposure, their cell materials were damaged by the ionizing radiation, and that was the cause of their sickness (and eventual death). But they weren't a problem to their environment, radiation-wise.

If you are *contaminated*, that means that on or in your body, you carry radioactive substances of significance. They will irradiate you, and depending on the kind of radiation, your surroundings. If it are alpha emitters (like plutonium) then the radiation will not leave your body (alpha radiation only travels a few micrometers in matter). But it will do a lot of damage locally. The most typical case of alpha contamination is the breathing of air containing powder or so of an alpha emitter, and the exposed area is the lungs.

Now, unless you have taken in A LOT of stuff, you are not an immediate radiation hazard for your environment, however, you might be considered a "leaky container" of radioactive material, and be an indirect hazard because you are essentially a "vessel from which radioactive material might escape".

If you have taken in a hard gamma emitter (cobalt or something), then you ARE a radiation hazard to your environment, because the radiation can leave your body. You are a walking source of radiation, and if you stand close to somebody, that person takes a comparable dose as you do (but only during the time he's near you, while you take it all the time of course). You are also a "leaky container".

For instance, after the SL-1 accident (see http://en.wikipedia.org/wiki/SL-1 for some info), the people exposed we so terribly contaminated, that one had to consider their bodies as "radioactive waste". But that's because they had reactor core material all over them.

The hazard is only there as long as the radioactive material is there, so if by radioactive decay, it has disappeared after a while, it is gone (but you have taken the dose nevertheless, and hence increased your chances of getting a cancer or so, because of the genetic modifications that it induced).

It all depends on the material you absorbed, the nature of the radiation it emits, and of course the quantity you absorbed.

 

[daveb]

It is possible to "become" radioactive as well by neutron radiation that activates atoms in your body, but this is a minute amount (enough neutron activation in the body to be detectable would probably kill you).

 

[Morbius]

Radiation can't be seen? Homer Simpson would say otherwise
In the (French?) movie 'Pu 237' a nuclear scientist working in a nuclear power plant was exposed to lethal doses of radiative material. Now even though he was washed down thoroughly, the man states in the movie that he couldn't stay near his family for long because of the radiation he was emitting. This contradicts your statement since he wouldn't have had any radiative materials on him. Is this foul play by the movie producers or is it possible?

Mentallic,

Are you looking for scientific accuracy in the MOVIES?

If the contamination were due to Pu-237; as per the movie's title; Pu-237 is indeed unstable; but it
converts to Neptunium-237 via electron capture. There is a VERY SMALL possibility; with a branching
ration of 0.0042% that the Pu-237 will decay by alpha to U-233. However, NEITHER of these decay
modes would be threatening to the family

Dr. Gregory Greenman
Physicist

 

[Morbius]

Or an intense enough radiation could induce radioactivity in elements already in your body by converting them into radioactive forms.

mgb_phys,

Elements already in your body could be transmuted to a radioactive species if you are exposed to
NEUTRON radiation from a reactor - i.e. you stand in the beam port of a research reactor.

But if we are talking about being exposed to some radioactive material that is emitting gammas or
betas - then NO - they will NOT make the elements in your body radioactive. [ This is what I
mean above that radioactivity is NOT "contagious"].

In order to make elements in your body radioactive; you need to alter the NUCLEUS of the atom and
transmute that to a radioactive form - by adding or knocking out a nucleon. Beta radiation, for instance;
is an electron and doesn't alter the nucleus.

Dr. Gregory Greenman
Physicist

 

[mgb_phys]

Agreed I did say it was unreasonable - but if the OP had read about induced radiation then claiming that radiation wasn't contagious would be wrong. As I said you would need to receive a serious dose (from a reactor or a nuclear weapon) that induced radiation would be the least of your worries.
I didn't mention neutrons or the source of radiation since it wasn't really a technical question.

The OP should not eat discarded smoke detectors or live in basements in areas with a lot of granite.
Other than that we have been trying to convince them not to worry for a year!

 

[Morbius]

Agreed I did say it was unreasonable - but if the OP had read about induced radiation then claiming that radiation wasn't contagious would be wrong.

mgb_phys,

I didn't says "radiation" was not contagious - I said "radioactivity" is not contagious.

I make that distinction. If you are exposed to "radioactivity" - that is you are exposed to a
nuclide that is not stable - then you are NOT going to become radioactive because the type
of radiations emitted by radioactive substances are not going to activate stable elements in
your body.

If you are exposed to the radiation from a reactor or a particle accelerator like a cyclotron - THEN
you can transmute stable elements into radioactive ones. The neutrons from a reactor - or high energy
alphas or protons from a cyclotron - can transmute stable elements into radioactive ones.

In general, for transmutation to occur - you need to be near a MACHINE - a reactor or cyclotron or
other particle accelerator.

If you are only near a SUBSTANCE that is radioactive - then you are NOT going to have stable
elements in your body transmuted to unstable forms.

RADIOACTIVITY [ as opposed to radiation ] is NOT "contagious"

Dr. Gregory Greenman
Physicist

 

[mgb_phys]

I didn't says "radiation" was not contagious - I said "radioactivity" is not contagious.

Good point -

Anyway to reassure the OP's fears.
If you get radioactive material on your skin (somehow)
- it's easily detected, plants and labs have amazingly sensitive scanners at their exits.
- your skin stops the most common forms of radiation
- once the material is washed off it doesn't leave any radiation or radioactivity behind
So unless you are in contact with a large amount of high activity material (which can do damage in a short time) it's not a problem.
Because it is so easily detected and washed off it's actually safer than a lot of lab chemicals - you really don't want to get HF on your hand!

Getting radioactive materials INSIDE your body is more serious ( as it is for any toxic chemical)
Some like Uranium or Plutonium are chemically inert and insoluble and will go through you without any real harm.
More serious are gases because they can be absorbed into your body through your lungs.
The most serious radiation health risk is from Radon produced naturally in areas of the country with Granite rocks. It builds up in basements and houses and you have to fit fans and ventilation to remove it.

 

[gmax137]

In the (French?) movie 'Pu 237' a nuclear scientist working in a nuclear power plant was exposed to lethal doses of radiative material. Now even though he was washed down thoroughly, the man states in the movie that he couldn't stay near his family for long because of the radiation he was emitting. This contradicts your statement since he wouldn't have had any radiative materials on him. Is this foul play by the movie producers or is it possible?

The Pu in the movie is a metaphor. The movie is not about radiation.

 

[Morbius]

The Pu in the movie is a metaphor. The movie is not about radiation.

gmax137,

It's my experience that NONE of the movies that mention nuclear power, or radiation, or...are ANYWHERE
NEAR being "realistic". Movies such as:

"China Syndrome"
"Red Alert"
"Atomic Twister"
"Atomic Train"

are TERRIBLY FLAWED!

They seem to be unresearched fantasies meant to scare little children.

Dr. Gregory Greenman
Physicist

 

[mgb_phys]

It's my experience that NONE of the movies that mention nuclear power, or radiation, or...are ANYWHERE NEAR being "realistic".

The Simpsons seems an accurate depiction of any large plant operation.

 

[Morbius]

The Simpsons seems an accurate depiction of any large plant operation.

mgb_phys,

You have me at a disadvantage; I've never watched the Simpsons; except I did
see the opening sequence in which some "green glowing" cylinder of material is
accidently dropped by Homer and in turn passes to several other characters
including Bart Simpson, who loses it to Homer as Homer drives up his driveway.

Therefore, the Simpson family's nightly TV watching is done in the company of this
"green glowing" cylinder.

If that sequence is "accurate"; I'l continue to take a pass on the Simpsons.

Dr. Gregory Greenman
Physicist

 

[mgb_phys]

Ok not the glowing green cylinder.
But everything else - especially the nodding bird toy to press 'Y' which replaced Homer

 

[334dave]

i hope these two cases were jest shop talk ..
i heard there was a case in Mexico of a scrap metal vender cutting open a capsule
.. inside was a power and it did glow in the dark
that his little kids put some on there faces as it lit up in the dark room..

of course they passed away and it was determined that it was a lost medical source such as americium or another isotope...

another time i heard of a pipe x-ray sorce that got loose and this worker picked it up and that it did glow when covered in the hands..
he put in it in his pocket for a while and after showing it to some one put in in the other pocket..
he lost both legs at the hip..
of course this is "hear say.."
which if the above were true then as the op asked then Yes you could see it.
but as it was overtime trash talk at glen rose texas ...i can as klink would say i know nothing ..

also ... a number of the guys thought it would be cute to ware homer T shirts and some put picts of him on their badges.. they were sent home ...
as were the folks that had T shirts saying i pick nits..

also GR is the reason that the public tours were folks get a simulated fuel pellet ..
that they now have a red or orange stripe..
seems that some one found a pellet laying in the fuel handling room after fuel come on site..
things got exciting for a bit..

 

[mgb_phys]

Accidents like that do happen - especially in less economically developed countries.
Scrap yards have detectors to pick up items like discarded smoke alarms or industrial radiation sources and of course equipment from hospitals and nuclear power plants should be tracked and disposed of carefully.

There is a list of events here http://en.wikipedia.org/wiki/List_of_civilian_radiation_accidents

Remember that these are only reported and make the news because of the scare about 'radiation'. 10-20,000 people died as a result of the Bhopal chemical plant accident but nobody remembers that and around 45,000 people die on the roads each year in the USA.

 

[Morbius]

i hope these two cases were jest shop talk ..
i heard there was a case in Mexico of a scrap metal vender cutting open a capsule
.. inside was a power and it did glow in the dark
that his little kids put some on there faces as it lit up in the dark room..

334dave,

Radioactive sources don't really glow in the dark - except on TV.

You need some type of scintillation medium around to get the glow.

The Mexico story is somewhat true - a hospital in Mexico disposed of a radiotherapy
machine used for radiation treatment of cancers - the radioactive material was ultimately
"recycled" into consumer products like table legs. The reason it was discovered was
because a truchk carrying the material passed through the monitors at Los Alamos National Laboratory:

http://www.window.state.tx.us/border/ch09/cobalto.html

Dr. Gregory Greenman
Physicist

 

[Homer Simpson]

The "Goiânia accident" is the glow in the dark powder story (Cs-137). Google it or Wikipedia, pretty interesting, or this IAEA link http://www-pub.iaea.org/MTCD/publications/PDF/Pub815_web.pdf

Apparently there likely was a glow, from Čerenkov radiation, the same that glows off fuel bundles under water in the IF bays.

In this case as Morbius says, I guess the scintilation medium is water, or moisture in the air.


So if you're ever in Brazil and someone tries to sell you glowing powder, you should be able to use this story to haggle the price down a bit.

 

[Morbius]

Apparently there likely was a glow, from Čerenkov radiation, the same that glows off fuel bundles under water in the IF bays.

In this case as Morbius says, I guess the scintilation medium is water, or moisture in the air.

Homer,

You need a pretty intense radiation field to see Cherenkov radiation - as in the radiation from an
operating reactor core, or a critical assembly, or some spent fuel that was fairly recently taken out
of the reactor.

Or in the case of the accidental criticality accident; such as those that occurred at Los Alamos with
bomb cores - you get an ionization flash - the radiation intensity is enough to ionize the air.

Dr. Gregory Greenman
Physicist

 

[334dave]

334dave,

Radioactive sources don't really glow in the dark - except on TV.

You need some type of scintillation medium around to get the glow.

The Mexico story is somewhat true - a hospital in Mexico disposed of a radiotherapy
machine used for radiation treatment of cancers - the radioactive material was ultimately
"recycled" into consumer products like table legs. The reason it was discovered was
because a truchk carrying the material passed through the monitors at Los Alamos National Laboratory:

http://www.window.state.tx.us/border/ch09/cobalto.html

Dr. Gregory Greenman
Physicist

OK you got me, i only finished hs..
in a watchmakers bench i bought there is a vile of radium, from way before my time, for to put on watch hands to glow in the dark..it is labeled as such..
so why would that glow? why would other sources NOT glow..
i under stand my tritium (H3 ?) watch has a gas that glows ..
i would hazard a guess that it is possible to have some thing around or mixed in that would glow from the ionizing radiation.. on the order of say..
like propane and natural gas have no order .. it is added..

on a side note..
i am surprised no one has informed then casual readers that the purity deep blue glow from reactor cores is from the partials exceeding the speed of light..

 

[mgb_phys]

The glow from tritium or radium is not the radiation. The glass is coated with phosphors which emit light when excited by the beta emission from tritium.
It's exactly the same as a TV, electrons from the CRT hit phosphors on the screen to give you the picture.

 

[Homer Simpson]

You need a pretty intense radiation field to see Cherenkov radiation -

Just for interest sake, that IAEA report says in the house where the Brazilian fellow dismantled the tube of Cs-137, just due to some small amounts on the ground, measured about 6 Gray per hour at 1 meter distance, (600 Rem/h I think?) which to me seems really unbelievably high. You'ld receive your allowable yearly dose as a nuclear energy worker in about 30 seconds standing in that house.

No getting that level of contamination past a rad detector.

(I'm certainly not trying to say that level is comparable to radiation levels off a spent bundle, nor do I have any clue what level would cause Cherenkov radiation)

 

[Mentallic]

Mentallic,

Are you looking for scientific accuracy in the MOVIES?

If the contamination were due to Pu-237; as per the movie's title; Pu-237 is indeed unstable; but it
converts to Neptunium-237 via electron capture. There is a VERY SMALL possibility; with a branching
ration of 0.0042% that the Pu-237 will decay by alpha to U-233. However, NEITHER of these decay
modes would be threatening to the family

Dr. Gregory Greenman
Physicist

While title Plutonium is for another matter in that movie. The source of radiation is unspecified if I remember correctly but it was because of a heavy gas leak in a nuclear power plant. Now if the movie were to have any credit for producing *some* scientific accuracy, the producers could argue that the leakage that irradiated this man was from another substance entirely (could there be any elements/isotopes that, if matter were exposed to its radiation, would too become radioactive?)

The Pu in the movie is a metaphor. The movie is not about radiation.

I don't want to get into great detail about the movie, since the only highlight of it all was when

Spoiler

The thugs mistaked the plutonium powder for drugs and began sniffing it

. But yes, the plot of the story is based mainly upon human psychology.

The Simpsons seems an accurate depiction of any large plant operation.

Especially when the gas is vented way out in the country - where no one cares - on the farm crops. How about when Homer's instinctive reaction to meltdowns, as being a veteran safety inspector, is to destroy the control console by throwing water over it
Homer always seems to solve his problems without any effort at all. My role model!

 

[Morbius]

OK you got me, i only finished hs..
in a watchmakers bench i bought there is a vile of radium, from way before my time, for to put on watch hands to glow in the dark..it is labeled as such..
so why would that glow? why would other sources NOT glow..

334dave,

Because the vial contains a mixture of radium and phosphorous. The radium emits alpha radiation
which excites the electrons in the phosphorous - and when they return to ground state - they emit
photons of light.

on a side note..
i am surprised no one has informed then casual readers that the purity deep blue glow from reactor cores is from the partials exceeding the speed of light..

In the water surrounding the reactor core, you see the blue Cherenkov radiation because electrons are
exceeding the speed of light IN THE WATER - they are NOT exceeding the speed of light in a vacuum;
that is forbidden by Einstein's Theory of Special Relativity.

Dr. Gregory Greenman
Physicist

 

[mgb_phys]

nor do I have any clue what level would cause Cherenkov radiation)

A single neutrino can cause Cherenkov radiation - there are telescopes that will detect that.
Cerenkov radiation in air is rare because air has a refractive index only slightly > 1, the particle has to be going very near light speed to beat this. It's more common in water because with n=1.3 you only need to go at 0.75c

The intensity of the Cherenkov light depends on the number of particles not their energy. Although the wavelength depends on the energy and your eye's sensitivity to light does depend on wavelength.

I wouldn;t have thought you would see Cherenkov in air from even an open reactor. A very strong source might ionise air enough to give a similair blue glow (like blue electrical sparks).

 

[Morbius]

The intensity of the Cherenkov light depends on the number of particles not their energy. Although the wavelength depends on the energy and your eye's sensitivity to light does depend on wavelength.

mgb_phys,

The wavelength of the Cherenkov radiation deos NOT depend on the energy of the particle,
except secondarily.

The photons of Cherenkov radiation are de-excitation of the transparent medium after being excited
by the charged particle. The reason that we see a blue glow in a swimming pool reactor does NOT
have to do with the energy of the high-energy particles from the reactor. The blue glow is due to
the properties of the WATER - the particular atomic transitions that are being excited.

The only requirement for the energy of the high energy particles is that they be of sufficient energy
to excite the particular atomic transitions in the water or other transparent medium.

Dr. Gregory Greenman
Physicist

 

[334dave]

mgb_phys,

The wavelength of the Cherenkov radiation deos NOT depend on the energy of the particle,
except secondarily.

The photons of Cherenkov radiation are de-excitation of the transparent medium after being excited
by the charged particle. The reason that we see a blue glow in a swimming pool reactor does NOT
have to do with the energy of the high-energy particles from the reactor. The blue glow is due to
the properties of the WATER - the particular atomic transitions that are being excited.

The only requirement for the energy of the high energy particles is that they be of sufficient energy
to excite the particular atomic transitions in the water or other transparent medium.

Dr. Gregory Greenman
Physicist

yes i knew of the changing of speed of light in water ..
the rest of your answer was most informative!
so.. leading to another wandering of mine..
as in a clear gem diamond the speed of light is even slower then in water
would we see a glow from the diamond that is different then in water under the same conditions?
i know many gems gain much enhanced changing of color and depth of color from exposure to fields..
what causes this?

 

[vanesch]

It is possible to "become" radioactive as well by neutron radiation that activates atoms in your body, but this is a minute amount (enough neutron activation in the body to be detectable would probably kill you).

In order to activate biological material enough for it to become a radiation hazard itself, I never did the calculation, but I suppose that the material must already be cooked by a neutron beam before this happens.

What would btw be the most "sensitive" activation reaction ?

Hydrogen turns into deuterium, which is not active.
Carbon will indeed turn into C-14 somewhat (neutron capture on C-13, which consists of just about 1% of all carbon), so that's a potential hazard.
Nitrogen, not really. Only N-15 could activate, only 0.4% of nitrogen is N-15 and then it turns into N-16 which has a half-life of 7 seconds into stable oxygen.
Oxygen, not really. Only O-18 (0.2% of all oxygen) can activate, and becomes O-19 which decays in 27 seconds to stable fluor.
Fluor, F-19 (100% of natural fluor) activates to F-20 which decays in 11 seconds to stable Neon.
Sodium, yes. Na-23 (100% natural sodium) activates to Na-24 which takes 15 hr to decay to stable magnesium, so for a day or so, this is a potential hazard.
Magnesium, not really, only Mg-26 activates (11% of natural magnesium) to Mg-27 which decays in a few minutes to stable Aluminium.
Similar for aluminium and silicium.
Phosphorus, yes. P-31 (100% of natural phosphorus) will activate to P-32 which takes 15 days to decay to stable sulfur, so this will be a hazard for a few weeks.
Sulfur is also a problem, because S-34 (4% of natural sulfur) will activate to S-35 with a life time of 3 months to decay to stable chlorine. So this is a genuine candidate for activation.
Chlorine is a problem too, because Cl-35 (75% of natural chlorine) will activate to a long-living (300 000 years) Cl-36.
Potassium is a small problem, because K-41 activates to K-42 with a lifetime of 12 hours.
Calcium is a night mare: Ca-40 activates to Ca-41 (lifetime 100 000 years), Ca-44 activates to Ca-45 (half a year).

There are a few others of course. You can verify all this on the nuclid chart of the NNDC.

 

[Morbius]

as in a clear gem diamond the speed of light is even slower then in water
would we see a glow from the diamond that is different then in water under the same conditions?

334dave,

Yes - the electron energy levels and their spacings in a diamond are different from the electron
energy levels and spacings of water. Therefore, you are going to see a different glow from a
diamond than what you see with water.

It's just like you see a different glow from a "neon light" when the gas inside is neon, giving you
a red glow; as opposed to the gas inside being krypton, which gives a green glow.

Dr. Gregory Greenman
Physicist

 

[334dave]

thank you Morbius!
had suspected it would glow...but thought it would be blue also..
i can not but wander at what color it could be!
but to other musings..
vanesch- in this thread there are discussions as to that only under the right conditions would objects become emitters of ionizing emissions..
you bring up some materials that this could happen to most easily..

i recall much fan fair once over exposing gemstones to enhance color
i have heard tails of some persons taking stones and putting them in the field of cancer treatment fields, ct machines and neutron beams ...
along with strong claims that this would cause the stones to become "hot"
some of the materials you mention are components of gemstones that affect color ..
what are your (or any ones !) thoughts concerning this?

also in some conversation some one spoke of setting off portals from med testing..
this happen to me personally and i caused much alarm for a short while..
at a slow nutron resurch center --
i was at a last point check point frisking station..
a few days before had received 'something' for cardiac testing ..
on placing my hand near the friskier it went off..
i had much fun seeing how little of my self and how close i had to be to set it off..
health phisics come running and ...
well i was restricted in were i could go for a while to say the least..
i asked if my badge had fogging on it but was never told and was issued a new badge after testing showed i was not "hot" ..
another place was also told to loose my glow in the dark watch as it had a source in it..

NOTE: it is not fun to lay in lead box while the machine slowly moves over you..

 

[mgb_phys]

You can improve (some) gemstones by irradiation. Many coloured stones are Aluminium Oxide with traces of heavy metals to give the color, change the metals (or even just their oxidation state) and you change the color.
You probably need something a bit stronger than radiotherapy dose though http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/irradiated-gemstones.html

The alarms are really a demonstration of how sensitive you can make radiation detectors.
Imagine if an alarm went off at a hospital if a doctor entered with a single bacteria on their skin. Or a meat packing plant worker left the site with a single animal blood cell on their boots.

 

[Vanadium 50]

The reason that we see a blue glow in a swimming pool reactor does NOT have to do with the energy of the high-energy particles from the reactor. The blue glow is due to the properties of the WATER - the particular atomic transitions that are being excited.

I'm a little puzzled by this. One also gets a characteristic blue glow using glass. Why should that be?

 

[Gokul43201]

334dave,

Because the vial contains a mixture of radium and phosphorous.

Minor correction: the vial likely contained a mixture of radium and a zinc sulfide based paint/dye (not phosphorus). Zinc sulfide (when doped appropriately) is phosphorescent.