Radio active...

Radio active. I need help understanding this. Radio active means something is radiating something correct? Radiation what? We can sum up the 'what', in general, by calling it energy.

So radio activ means radiating energy. Everything radiates energy. So... Well, what's radio active 'bad' vs. radio active 'normal'?

Anyone with a general jist of an understanding? I've got a brain storm going on and don't want to loose train of thought by doing hourse worth of googleing and reading.

Thanks

When something is labeled radioactive, it typically means it emits Alpha, Beta, or Gamma radiation in doses that could potentially harm living things.

Yes, you are right, EVERYTHING is radioactive at a small level, but only those that could cause harm actually get the warning label.

There are probably 1000 radioactive sources around you right now, but 999 of them are so minor that it would take three lifetimes for it to affect you. Alpha and Beta radiation are effectively harmless. Gamma radiation in large enough, concentrated doses will kill you pretty quickly.

Here's a pretty good page that explains radiation fairly well, and without going into really complicated details.

www.uic.com.au...

[edit on 6/20/2006 by Zaphod58]

Oh, you can get killed by alpha and beta radiation... you wont find anything that naturally produces those kind of levels, but in the right dosage, it will kill you... very slowly.

Alpha and beta radiation can only burn your skin... but, enough of it, and well, wont take long to burn the skin clean off.

Gamma is the real killer though as mentioned above. It takes a relatively small dose to kill someone.

Too bad it doesnt work like in the good old comic books eh?

Yes, as mentioned, everything does emit radiation... but in very small amounts.

What's dangerous is when a source emits a large amount of radiation.

If you take one of those rad-meters (they look like battery packs with a metal stick on it, and it makes "clicking" noises) and walk around with it, you'll here a bunch of clicks, but they're spaced out. That is normal radiation being given off by you and me and the sun and the stars.

However, put it next to something that's deemed "radioactive" (like naturally occuring uranium) and you'll here the frequency of the clicks speed up by a lot! That's because the uranium is releasing MORE radiation than most matter. Any time you hear a bunch of clicks in *very* rapid succession, it means you're near a potentially hazordous emitter of radiation.

Now, uranium isn't actually that bad. Handling it without protective gloves is bad for you (though you could never tell), and living in the same house as it if it's unprotected (say in your entrance) is also bad for you. However, keeping some distance, or some wall, between you and it essentially completely eliminates it's danger. That's because it's basic radiation.

The dangers with Gamma radiation is that Gamma rays can go through most ordinary matter. If it stops light, it stops Infra-red, but almost nothing stops gamma. You need very thick concrete walls to stop it, or comparatively thick walls of lead shielding. Gamma isn't nice because it's hard to contain - whilst the others are comparatively easy to contain.

Originally posted by johnsky
Oh, you can get killed by alpha and beta radiation... you wont find anything that naturally produces those kind of levels, but in the right dosage, it will kill you... very slowly.

Alpha and beta radiation can only burn your skin... but, enough of it, and well, wont take long to burn the skin clean off.

Gamma is the real killer though as mentioned above. It takes a relatively small dose to kill someone.

Too bad it doesnt work like in the good old comic books eh?

Yeah, that's why I say Alpha and Beta are EFFECTIVELY harmless. Because they're quite easy to shield against, and would take such a large dose to kill you.

Originally posted by Zaphod58

Yeah, that's why I say Alpha and Beta are EFFECTIVELY harmless. Because they're quite easy to shield against, and would take such a large dose to kill you.

FOIL HAT!

You'll need a dense metal like lead or heavier for gamma though.

Originally posted by Yarium
Yes, as mentioned, everything does emit radiation... but in very small amounts.

What's dangerous is when a source emits a large amount of radiation.

If you take one of those rad-meters (they look like battery packs with a metal stick on it, and it makes "clicking" noises) and walk around with it, you'll here a bunch of clicks, but they're spaced out. That is normal radiation being given off by you and me and the sun and the stars.

However, put it next to something that's deemed "radioactive" (like naturally occuring uranium) and you'll here the frequency of the clicks speed up by a lot! That's because the uranium is releasing MORE radiation than most matter. Any time you hear a bunch of clicks in *very* rapid succession, it means you're near a potentially hazordous emitter of radiation.

Now, uranium isn't actually that bad. Handling it without protective gloves is bad for you (though you could never tell), and living in the same house as it if it's unprotected (say in your entrance) is also bad for you. However, keeping some distance, or some wall, between you and it essentially completely eliminates it's danger. That's because it's basic radiation.

The dangers with Gamma radiation is that Gamma rays can go through most ordinary matter. If it stops light, it stops Infra-red, but almost nothing stops gamma. You need very thick concrete walls to stop it, or comparatively thick walls of lead shielding. Gamma isn't nice because it's hard to contain - whilst the others are comparatively easy to contain.

unfortunately most of your statements are wrong. If a geiger counter (which im assuming you are referring to) measures a bunch of clicks in rapid succession, it does not necessarily mean it is potentially dangerous. You have to know about the source of radiation to gauge whether it is dangerous or not. Naturally occurring uranium is a beta emitter; beta energy has a range of a few mm if incident on paper and can be handled without it being harmful.

also, living in a house with uranium in it.... I think you mean radon, progeny of natural uranium. The inhalation of radon is dangerous.

Your next statement is that gamma radiation can go through most ordinary matter and almost nothing can stop it: wrong. The transmission of gamma radiation is dependent on a few parameters: the material composition of the 'matter' and the energy of the gamma radiation. Anything can stop gamma radiation within reason. you need to do your homework.

Originally posted by johnsky
Oh, you can get killed by alpha and beta radiation... you wont find anything that naturally produces those kind of levels, but in the right dosage, it will kill you... very slowly.

Alpha and beta radiation can only burn your skin... but, enough of it, and well, wont take long to burn the skin clean off.

Gamma is the real killer though as mentioned above. It takes a relatively small dose to kill someone.

Too bad it doesnt work like in the good old comic books eh?

I don't know what you mean by it takes a small dose to kill someone from gamma radiation? This statement is incorrect. There are certain guidelines set out by regulatory agencies, which specify the maximum annual dose for various members of the public (i.e., general population, nuclear energy workers, etc..). Doses in excess of these limits are tolerable to a certain extent, however, you would need a large dose for it to be fatal.

The way it seems to be is that the more penetrative the type of radiation the less strong it is - alpha is the strongest but is easily protected against, and vice versa for gamma with beta in between.

With small doses you can survive certainly, though you will suffer from radiation sickness and the increased risk of cancer.

Radon is a serious risk in many houses, as it is hard to detect and naturally occuring. In fact most background radiation is naturally occuring, also the remnants of the likes of Chernobyl and the nuclear weapons tests would still have an effect on this.

Originally posted by porky1981

Originally posted by johnsky
Oh, you can get killed by alpha and beta radiation... you wont find anything that naturally produces those kind of levels, but in the right dosage, it will kill you... very slowly.

Alpha and beta radiation can only burn your skin... but, enough of it, and well, wont take long to burn the skin clean off.

Gamma is the real killer though as mentioned above. It takes a relatively small dose to kill someone.

Too bad it doesnt work like in the good old comic books eh?

I don't know what you mean by it takes a small dose to kill someone from gamma radiation? This statement is incorrect. There are certain guidelines set out by regulatory agencies, which specify the maximum annual dose for various members of the public (i.e., general population, nuclear energy workers, etc..). Doses in excess of these limits are tolerable to a certain extent, however, you would need a large dose for it to be fatal.

I said relatively small... in relation to the levels of Alpha and Beta radiation required to kill you... as nobody has ever managed to get killed directly by alpha and beta radiation (aside from skin cancer), yeah, its relatively a very small dose.

has anyone ever managed to kill themselves with Alpha or Beta emissions?...

better question... has anyone ever managed to be stupid enough to stand in the path of a microwave... Oh well, natural selection and all that, whot?

[edit on 21-6-2006 by johnsky]

Originally posted by porky1981
unfortunately most of your statements are wrong. If a geiger counter (which im assuming you are referring to) measures a bunch of clicks in rapid succession, it does not necessarily mean it is potentially dangerous. You have to know about the source of radiation to gauge whether it is dangerous or not. Naturally occurring uranium is a beta emitter; beta energy has a range of a few mm if incident on paper and can be handled without it being harmful.

Terribly sorry there sir, but I think you misinterpreted what I said. I gave an example - more clicks when near something deemed "radioactive". I did not say that all sources of clicks are dangerous.

Originally posted by porky1981
also, living in a house with uranium in it.... I think you mean radon, progeny of natural uranium. The inhalation of radon is dangerous.

No, I meant uranium. Now, I also said it'd have to be somewhere well-travelled (such as your entrance), and I didn't give a time-span for how long it would take to affect you.

Originally posted by porky1981
Your next statement is that gamma radiation can go through most ordinary matter and almost nothing can stop it: wrong. The transmission of gamma radiation is dependent on a few parameters: the material composition of the 'matter' and the energy of the gamma radiation. Anything can stop gamma radiation within reason. you need to do your homework.

Once again, my apologies, I used the term "almost nothing stops" as a sort of dramatic phrasing. Of course it can be stopped, but it does go through thin or low-density materials with considerable ease.


In the end, whilst you may think I need to do my homework, I think you need to brush up on your manners and then feel free to tell me that I'm "partially right and partially wrong" - which is just a kinder and more constructive way to tell me that I am, still, wrong. That way we can make this forum a better place for people to learn in, don't you agree? Thanks for your time, I'm glad that we had this informative little chat.

Clavius.org has a page that talks about radiation. It s a good read. www.clavius.org...

Originally posted by Yarium

Originally posted by porky1981
unfortunately most of your statements are wrong. If a geiger counter (which im assuming you are referring to) measures a bunch of clicks in rapid succession, it does not necessarily mean it is potentially dangerous. You have to know about the source of radiation to gauge whether it is dangerous or not. Naturally occurring uranium is a beta emitter; beta energy has a range of a few mm if incident on paper and can be handled without it being harmful.

Terribly sorry there sir, but I think you misinterpreted what I said. I gave an example - more clicks when near something deemed "radioactive". I did not say that all sources of clicks are dangerous.

Originally posted by porky1981
also, living in a house with uranium in it.... I think you mean radon, progeny of natural uranium. The inhalation of radon is dangerous.

No, I meant uranium. Now, I also said it'd have to be somewhere well-travelled (such as your entrance), and I didn't give a time-span for how long it would take to affect you.

Originally posted by porky1981
Your next statement is that gamma radiation can go through most ordinary matter and almost nothing can stop it: wrong. The transmission of gamma radiation is dependent on a few parameters: the material composition of the 'matter' and the energy of the gamma radiation. Anything can stop gamma radiation within reason. you need to do your homework.

Once again, my apologies, I used the term "almost nothing stops" as a sort of dramatic phrasing. Of course it can be stopped, but it does go through thin or low-density materials with considerable ease.


In the end, whilst you may think I need to do my homework, I think you need to brush up on your manners and then feel free to tell me that I'm "partially right and partially wrong" - which is just a kinder and more constructive way to tell me that I am, still, wrong. That way we can make this forum a better place for people to learn in, don't you agree? Thanks for your time, I'm glad that we had this informative little chat.

no, not really. There are three interactions you should look up....photoelectric absorption, compton scattering and pair-production. This will give you a better idea of gamma radiation interactions in materials.