Talk:Radiation

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Immunity?[edit]

Can anyone be immune to the effects of nuclear radiation? 71.212.224.185 18:23, 18 September 2007 (UTC)

Comparison[edit]

Compare this to taking one aspirin a day (which we may call background level); this has been proven to be harmless for most people, and actually has substantial medical benefits for many people. If one were to take one million aspirin a day, that person would poooop immediately.

What kind of comparison is that???

It is a smellyyyy comparison. What precisely is your objection? RK

no —Preceding unsigned comment added by 84.71.63.246 (talk) 16:41, 8 November 2007 (UTC)

that would be a drug overdose —Preceding unsigned comment added by 172.142.49.148 (talk) 15:40, 25 January 2008 (UTC)

EM radiation[edit]

I'm a kid doing research can we put this in more kid friendly language?

could you put it in different words


Can we please fold in the information from electromagnetic radiation and particle radiation into this article? I think it makes more sense as one single article. -- Alex.tan 07:10, 16 Sep 2003 (UTC) there is a em spectrum consisting of seven waves they are radio waves micro waves infa red visible light ultra violet x rays and gamma the ones at the start of the spectrum eg radio micro are harmfull to humans and can cause mutations. —Preceding unsigned comment added by 172.142.49.148 (talk) 15:44, 25 January 2008 (UTC)

You left out terahertz radiation. :-)
Also, X-Rays and Gamma Rays are the same thing---high energy photons. The photons are traditionally called X rays if they originate from the electron shell of an atom, and they are called gamma rays if they originate in the nucleus, but that's as far as the difference goes. Some gamma rays are more energetic than some X rays, and some X rays are more energetic than some gamma rays. If there's a source of, say, 1MeV photons hidden behind a window, and you set up detectors outside the window, there's no experiment you can do that will tell you for sure whether the source is an X ray source or a gamma source. 141.158.72.233 (talk) 01:33, 9 December 2008 (UTC)
So, what do you suggest? We should call them all HEPs, or perhaps HEWs in their wave forms? You aren't going to get many physicists to buy into that. Sometimes you have to go with the established terms, even when the difference is marginal. We're not here to break new ground in either physics or English. SkoreKeep (talk) 09:46, 15 February 2014 (UTC)

radiation hormesis[edit]

I would like some clarification on this new paragraph: Other scientists would point out that life of 2 billion years ago was very different from what it is now; for instance, oxygen was deadly to most life at the time. And while certain rivers of the former Soviet Union contain shellfish that make a Geiger counter cringe yet appear otherwise healthy, that's hardly reason for human beings to, say, dose themselves daily with radium salts as was once fashionable, or use cesium-137 pellets as handwarmers.[1] They'd point out that they are not arguing by mere logic, but by empirical results, such as the Petkau effect, that demonstrate certain highly nonlinear biological responses to radiation. In any case, linear extrapolation is an assumption that must be tested the same as anything else in science; one would not predict, say, superfluidity by linear extrapolation from warmer temperatures.

Given the comment given in the summary line when this paragraph was added, and given its placement and grammar, it appears as if this paragraph is trying to rebut the idea of radation hormesis. Yet midway in the paragraph it ends up with precisely the same logic used by advocated of radiation hormesis. In fact, the article already stated the exact same thing: linear extrapolation is an assumption that must be tested the same as anything else in science. Thus, I am wondering if the author could clarify his meaning? RK 01:53, Dec 16, 2003 (UTC)

radioactivity[edit]

This page used to be more-or-less duplicated on radioactivity. I've rewritten that, but preserved the old content on Talk:radioactivity since that stuff has received different improvements than this. Ugh.

I'm also planning to do some significant rearrangement and restructuring of this page to separate its content from radioactivity and radioactive contamination. I'll try to leave the contentious parts untouched as I'm not interested in edit-warring with anyone. --Andrew 04:23, May 6, 2004 (UTC)


Mess?[edit]

(William M. Connolley 17:01, 2 Jun 2004 (UTC)) The beginning of this appears to be a bit of a mess (which I don't have time or brain to fix now: sorry). Anyway, radiation is apparently waves (electromag) or particles. And light can be either, by QM. This is the wrong distinction: all sorts of rad are waves or particles, depending on how you look at them. Some particles are equivalent to electromag (ie are light). But others (alpha rad, say) aren't.

A bit later we are told that ligh isn't ionising but surely this depends on the material concerned? What about photograpy (of the old fashioned sort).


This article is indeed a mess. The real distinction is this:
  1. Some people talk about "radiation" and mean "electromagnetic waves", of any energy. (Or photons, if you prefer).
  2. Some people talk about "radiation" and mean "Something that comes flying through space and ionizes molecules". This can be high-energy photons (UV and higher; not visible light), alpha or beta particles.
Of course, there are other things that might be called radiation: neutrons, which are neither photons nor ionizing but come flying out of nuclear reactors and convert nuclei into radioactive isotopes, or gravitational, neutrino, and miscellaneous other radiation.
The biggest problem with this article is that it wants to be about ionizing radiation only but doesn't just break down and say so.
I am inclined to make this article be essentially a disambiguation page, and move most of its contents to a page on ionizing radiation; there's already one for electromagnetic radiation, as well as fast neutrons and slow neutrons. --Andrew 06:25, 10 Jun 2004 (UTC)
The title is "radiation." The article ought to acknowledge that "radiation" has more than one meaning. 151.201.126.48 (talk) 18:44, 29 May 2010 (UTC)

Moved to ionizing radiation[edit]

In view of the persistent problems with this page, its content was moved to ionizing radiation, which is what it was actually about. The page was then made into a disambiguation page discussing the different kinds of radiation. I expect there are more. --Andrew 07:06, 10 Jun 2004 (UTC)

Addition Of Thermal Radiation[edit]

Thermal radiation should be added to the list, as it is one of the three methods of heat flow and thus just as immportant as the others listed. I might add it myself if no one else does.

(William M. Connolley 08:24, 18 Jun 2004 (UTC)) Thermal radiation is just a case of electromagnetic radiation.
Thermal radiation should be (and is) in the list, not because it is a "method of heat flow", but because it is a type of radiation.
We should always be conscious of the fact that whenever we say "radiation," we are talking about a mechanism, we are not just talking about the photons that fly through space. Thermal radiation is different from, say, the radiation that takes place in a carbon dioxide laser; The mechanism is different, the energy spectrum is different, the geometry is different. 141.158.72.233 (talk) 01:43, 9 December 2008 (UTC)

Neutron radiation[edit]

In an older version of this page, one of the kinds of radiation discussed was neutron radiation. Certainly it is a kind of particle radiation, but then so is all ionizing radiation. More to the point, it is difficult to find the pages on fast neutrons and slow neutrons by following the link to particle radiation. These are an important kind of radiation that people should be able to find. Unfortunately we do not have a tidy page on neutron radiation, regardless of velocity.

I admit I am a little biased: I think particle radiation is a rather silly notion in the first place, quantum mechanics being what it is. For what it's worth, the top Google hits are mostly clones of our article. The others use it roughly the same way we do, with some mention of neutrinos but none of neutrons. (I suppose neutron radiation has a maximum range, since neutrons have a finite half-life). --Andrew 15:57, 18 Jun 2004 (UTC)

Perhaps I should elaborate: I don't think it makes sense for this page to try and neatly classify up the kinds of radiation into non-overlapping categories. I think this is essentially a disambiguation page, and its purpose is to point people to the article they actually wanted. So listing important subtypes here shouldn't be a problem unless this page begins to become unnecessarily huge. --Andrew 16:03, 18 Jun 2004 (UTC)

I agree, so I put a section on neutron radiation back on. If anyone doesn't like it, feel free to delete it (with reason of course).--129.82.69.48 (talk) 17:01, 13 September 2009 (UTC)

I would argue that thermal neutrons are not "radiation." Sure, they're invisible, and they're harmful, and they come from nuclear processes---all qualities that the celebrated T. C. Mits associates with "radiation"---but thermal neutrons don't carry energy, and they don't travel in straight lines. Thermal neutrons diffuse through matter like a gas. They are totally different from any other kind of "radiation." 74.111.185.200 (talk) 00:14, 31 October 2011 (UTC)
I see your point, but I think it should stay. The intro sentence reads "In physics, radiation is a process in which energetic particles or energy or waves travel through a medium or space." They do "carry" or have, energy which can be transferred, and they move through space. Not sure that "traveling in a straight line" is important. PRONIZ (talk) 14:40, 31 October 2011 (UTC)

Complexity[edit]

How complicated should this article be?

I ask because it had more information in it, which was taken out to simplify the page. In particular, it made the distinction between kinds of raditaion (electromagnetic, ionizing, gravitational) and processes producing radiation (thermal radiation, synchrotron radiation, etc). This seems like a valuable distinction to me.

(William M. Connolley 13:28, 19 Jun 2004 (UTC)) Ah... that may have been the


It is important that this page have enough information that readers can figure out what kind of radiation they're looking for. So, for example, they should know what kind of particle makes up electromagnetic radiation,

(William M. Connolley 13:28, 19 Jun 2004 (UTC)) Ah, but the problem is, how to say it? What sort of *particle* makes up electromag rad? Well none at all, when it isn't being a particle. Its then a wave field. But keeping on going through QM type stuff on a disambig page seems inappropriate.

and the relation between ionizing and electromagnetic radiation should be made clear. Gravitational radiation definitely needs some description.

OK, if you can describe it accurately but simply. But does it really need a description (see below)?

Is it appropriate to include things like synchrotron radiation here? I originally put it in, thinking that people might be looking for almost any use of the word "radiation". But if complexity of this page is an issue, they're not essential (although they should be described in the relevant pages - it's hard to find synchrotron radiation from electromagnetic radiation, for example).

I ask mostly because we seem to be making conflicting changes and I really don't want edit wars. --Andrew 21:58, 18 Jun 2004 (UTC)

(William M. Connolley 13:28, 19 Jun 2004 (UTC)) Twas me that made some of these changes. I argue that this is a disambig page: it should have refs to as many things as are useful (which is why the neutron stuff went in, cos someone said they were hard to find otherwise) but *not* attempt to describe anything in detail. In particular, I deleted the text around gravitation radiation because I felt it was wrong, but couldn't think of anything (short) better. But does the idea need a description to be recognised?

Questions[edit]

  • what name is given to cultures for identification of roganisms, as well as the identification of senstivities fo the organism to antibiotics?
  • what are the instruments or devices used for the detection of radiation?

greek-radiation[edit]

Radioactive contamination[edit]

I'd like to retain an external link to this article, because scientifically illiterate readers can confuse the two, for instance by saying something like "The accident caused radiation to leak from the facility." --Smack (talk) 07:20, 28 December 2005 (UTC)

Black body radiation[edit]

Should we include Black body radiation? It seems that given some of the others on the list it would not be out of place but I wonder if anyone woudl ever accidently link here when that is what they want. Dalf | Talk 04:35, 18 January 2006 (UTC)

We should definitly include black body radiation. We should combine the two articles into one. Notyouravgjoe | Talk 20:17, 21APR06

I've added a new heading, "Black Body Radiation", that references the pre-exising "Thermal Radiation" heading.71.240.50.3 (talk) 17:31, 4 December 2008 (UTC)

Particle versus Wave Radiation[edit]

...I am having a foggy-headed day, and so my attempt is probably a bit sloppy, but if someone could spiff up my attempt to explain the difference between "radiation", a-la DNA damaging particles emitted from decaying materials, and "radiation", simple waves which don't really effect things other than making them vibrate differently, it'd be a huge help to the article.

Much of the mythology about, say, mobile phones giving you ear cancer or microwave ovens making your food dangerous come from people not realizing that what we have is more or less two synonyms, very different things being called "radiation". No amount of time sitting in front of your TV can make you radioactive, the lattere is a whole different concept.

That is a vital piece of information for this article to deliver--Kaz 22:39, 26 June 2006 (UTC)

Um, It's not so much "ear cancer" as brain cancer, and there is an ever-growing body of evidence to suggest that chronic exposure to low levels of non-ionizing EMR can lead to cancer. 68.61.121.194 (talk) 16:42, 26 November 2008 (UTC)

In fiction[edit]

Shouldn't there be a little section titled "Radiation in Fiction", where it describes how radiation is often used in science fiction to create monsters? Sure it's ridiculous but it's so widespread that it should be discussed in this article. Ratso 05:04, 26 November 2006 (UTC)

Go ahead and writ one.  Andreas  (T) 14:24, 26 November 2006 (UTC)

Meaning[edit]

Radiation is a very general term and needs a disambiguation page, in my opinion. Most lay-readers will be looking for ionising radiation i.e. danger from nuclear power and so on. However, this is by no means the only important kind, but bunging together a load of only tenuously-related material in one article is a bad idea. Sojourner001 17:46, 26 January 2007 (UTC)

Radiation vs. wave: The linguistic differences[edit]

Although the word radiation is used haphazardly by the press, we try to use it somewhat more precisely in physics. All radiation can, in one way or another, be seen as a wave. The other way, electromagnetic and particle waves can obviously be observed as particles. Radiation is given by Encyclopædia Britannica as:

either the process by which energy is emitted from a source and propagated through the surrounding medium or the energy involved in this process. Familiar examples of radiant energy include light (a form of electromagnetic radiation) and sound (a form of acoustic radiation).

Radiation and waves can generally be used interchangeably when talking about things like uv-light or microwaves. However, in Norwegian (my native language), they have a slightly different connotation. Radiation implying that we are talking about a phenomena where the particle nature is becoming dominant (eg. high-energy, ionizing). Wave implying the opposite; the wave nature is dominant (low energy, non-ionizing). Since the words are technical words part of the international scientific community, I believe they have the same connotation in English. Can someone with good knowledge of both physics and the English language confirm this? --Tunheim 08:46, 7 February 2007 (UTC)

This is a matter of usage, in physical terms, radiation and waves are synonymous.  Andreas  (T) 16:56, 25 April 2007 (UTC)

The article on particle radiation lists ultrasound as a non-ionizing radiation. True or false? Same section links to [2] that has a publication on harmful effects of ultrasound.--Aravn 21:23, 7 November 2007 (UTC)

UV rays[edit]

I know only a little bit of physics, but I am now kind of confused about ionizing radiation and non-ionizing radiation after reading this. In this article it classified UV radiations as a kind of non-ionizing radiation, but in another article, the EM radiation it reads "The light from the Sun that reaches the earth is largely composed of non-ionizing radiation, with the notable exception of some ultraviolet rays." So, i am a little bit confused, is UV an ionizing radiation? Or is that the difference between ionizing and non-ionizing radiation is not as clear as black and white? If so, should the sentence "There are two 'distinct' types of radiation" be modified?

  • Radiation is either ionizing or non-ionizing. Technically UV radiation is any radiation with a shorter wavelength than violet light. The problem you are facing is that there is a distinction between UV "light" and UV "radiation." UV light is non-ionizing, while UV (anything with a smaller wavelength than Violet light) "radiation" is ionizing. Starkrm 17:17, 15 April 2007 (UTC)
Please sign your comments. --Tunheim 10:58, 15 April 2007 (UTC)
Also, it's important to realize that there is no absolute boundary on what energy level of radiation that is ionizing and what is not. It is quite possible to find materials that are ionized by regular visible light. However, such materials will not survive out in the open, and as such they are uncommon in nature. Due to this it is common to categorize all radiation with frequency above visible light as ionizing radiation. But there is no clear definition since the phenomena is not something that has a natural level of definition. --Tunheim 11:03, 15 April 2007 (UTC)

Photons[edit]

It is essential to say that electomagnetic radiation is composed of photons. Radiation in form of waves can be any kind of radiation icluding alpha, beta, neutron etc. In fact radiation and waves are synonymous in modern physics. Therefore, I changed the definition of electromagnetic radiation to comprise the fact that it is composed of photons (as opposed to other kind of radiation). I also removed the restrictive use of "photons" in the opening paragraph.  Andreas  (T) 16:59, 25 April 2007 (UTC)

  • The physics on your thought here isn't right though. Alpha, Beta and Neutron are not, by any means a form of waves, they are most certainly particles. All waves do not exhibit particle behavior; consider water waves for example. I think you are confused about wave/particle duality. Particles may exhibit wave behavior under certain conditions and waves may exhibit particle behavior under certain conditions, but that does not mean that they are the same thing. Also radiation and waves are not synonymous in modern physics. Radiation may be in the form of particles, or waves, as seen on the atomic level, and both are actually forms of energy. EM radiation is not composed of photons but photons are the particle manifestation of EM radiation. Starkrm 15:54, 29 April 2007 (UTC)
Starkm, A beta (electron) is a wave if you choose to describe its behavior in terms of quantum mechanics, and it is a particle if you choose to describe its behavior in terms of mechanical laws. Note though, that the latter choice, though valid for some experiments, limits you to a late nineteenth century level of understanding. Same goes for neutrons, protons, photons, ..., even big things like alphas. They're all particles if you study them as such, and they're all waves if you study them as such. As for what they are really, that's easy. An alpha is two neutrons and two protons bound by the strong force, and a neutron is an up quark and two down quarks bound by the color force, and a quark is... Well, you get the picture. I'll leave the complete explanation as an exercise for the reader.
You probably think of Alphas, betas, and neutrons as "particles" because they are all fermions: They obey the Pauli exclusion principle, which can be crudely stated as, "no two can occupy the same space at the same time." It fits with most folk's idea of what a "particle" is like. Photons are bosons. They don't have that restriction, and that makes them more intuitively wave-like.
151.201.219.161 (talk) 04:42, 2 December 2008 (UTC)

Secondary Radiation[edit]

Would a separate article or, at least, a definition for "secondary radiation" be needed on Wikipedia (see definition here)? Or, perhaps, does it alreay fall under another type of radiation that is mentioned here? aNubiSIII (T / C) 23:17, 22 July 2007 (UTC)

Confusion[edit]

I was looking through this article and some links it points to, and noticed the following oddity: On this page, EM radiation is distinguished from particle radiation, while it is claimed that particle radiation is made of moving subatomic particles. Thing is, a photon is such a particle. In fact, if you follow the link to the article about particle radiation, you'll notice that a photon is, in fact, on the list of particles there! Therefore, it would appear that EM radiation is, in fact, a sort of particle radiation. Being no expert on physics myself, I can only assume that it was meant that particle radiation is made of particles other than photons, i.e. ones that don't display particle/wave duality. If so, I'd say that should be expressed more clearly. Either way, either this page, or the one on particle radiation, should definitely be changed somehow to deal with this confusion. —Preceding unsigned comment added by 89.138.227.172 (talk) 00:46, August 30, 2007 (UTC)

weak! —Preceding unsigned comment added by 124.107.40.19 (talk) 22:14, 13 October 2008 (UTC)

They all exhibit "wave/particle duality." Electrons, protons, photons, neutrons, etc. can all be described as particles or as waves. But note: Just because they can be described either way doesn't mean that they are. 21st century physicists don't have much use for the particle-oriented descriptions. They just use the word "particle" out of old habit. 151.201.219.161 (talk) 04:50, 2 December 2008 (UTC)

An atom with a contained excess of kinetic energy of motion can become physically unstable. This can be corrected by the emission of an amount of material with a sufficient amount of the excess energy such that the remaining material can again become physically stable. If the amount of emitted material is sufficiently large enough to have its own identity as a physical particle it is called particle emission. If it merely emits electromagnetic spectrum radiation the radiation is classified according to its spectral class. It is assumed that all electromagnetic radiation is emitted by the electrons of the atom.WFPM (talk) 16:18, 9 July 2011 (UTC)

yup[edit]

THIS SUCKS —Preceding unsigned comment added by 75.6.242.50 (talk) 02:43, 14 October 2008 (UTC)

To paraphrase, this is supposed to draw into the mouth by action of the lips and tongue which produces a partial vacuum. Is it possible for an Wikipedia article to accomplish such activity? — Preceding unsigned comment added by 71.245.114.202 (talk) 17:50, 12 December 2011 (UTC)

Types of Radiation[edit]

I have added light. I think that a lot more types are missing. Research Method (talk) 21:37, 29 October 2008 (UTC)

A new article plus remove picture[edit]

Electromagnetic radiation should be in a diffrent article with the exception of gamma. Also the picture at the top shows lead stoping gamma rays. This is untrue you cant stop gamma rays only weaken them to a safe level. And this is what lead dose. Not stop them outright —Preceding unsigned comment added by 86.131.125.242 (talk) 18:35, 7 January 2009 (UTC)

Radiation[edit]

If you are in a crowded place,you can feel the heat coming from the persons nearest to you.This is because all bodies radiate energy which is changed to heat when absorbed by another body.

The sun gives off light and heat.Light and heat are forms of radiant energy.heat from the sun travels through space.This heat is absorbed by land,water and air,so they become warm.Radiation is the transfer of heat through space. —Preceding unsigned comment added by Psalm345 (talkcontribs) 23:42, 4 March 2009 (UTC)

What I like...[edit]

This article keeps these concepts simple and short. If I feel like learning about any of the kinds of radiation, it sonly a click away. I think this article is quite good right now. —Preceding unsigned comment added by 130.234.5.136 (talk) 14:51, 10 March 2009 (UTC)

Error in "The electromagnetic spectrum" image[edit]

380nm = 7.89*10^14Hz / 750nm = 3.99*10^14Hz / 299.8 = 1*10^15Hz / Frequency 1*10-15Hz is not in visible spectrum ! / Wavelength and frequency measures are erroneously shifted. Softvision (talk) 17:27, 23 July 2009 (UTC)

Discovery[edit]

A recent edit [3] changed "pitchblende ... was two million times more radioactive than uranium, as described by Marie." to four hundred times. I presume this is M Curie's original perception vs the modern measurement? --Alastair Rae (talk) 15:36, 27 August 2009 (UTC)

Actually, pitchblende, an ore of uranium, is 13 times more radioactively intense than uranium metal, in the sense that it emits 13x more becquerels of radiation being emitted than there is in the refined metal with the same weight of uranium. The reason is that it contains not only uranium, but all the radioactive decay products of uranium. After 4.5 billion years it is in equilibrium (the number of uranium atoms decaying in an hour is matched by the number of atoms of stable lead appearing in an hour) and therefore the same applies to each decay product in the chain. Eventually, in a couple of billion years the same will be true of the now pure uranium sample, if left undisturbed until then. However, no doubt there is a whole lot more going on in the pitchblende than that single decay chain. SkoreKeep (talk) 00:23, 16 February 2014 (UTC)

Wilhelm Conrad Röntgen (27 March 1845 – 10 February 1923)died before tritium was discovered in 1934 by Rutherford and in any case it is an isotope of hydrogen and photographing a piece of it would be difficult, did not want to delete all of this but it is certainly in need of editing and referencing

(This article is inaccurate and needs significant revision regarding Tritium which was not discovered until the 1930s and is in any case Hydrogen and a gas at STP Roentgen was dead by this time.) —Preceding unsigned comment added by MarS (talkcontribs) 20:42, 13 July 2010 (UTC)

Cell Phone Radiation[edit]

Is there any truth behind the speculation that Cell phone usage can lead to Brain Cancer? Moeali123 (talk) 04:38, 16 June 2010 (UTC) —Preceding unsigned comment added by Moeali123 (talkcontribs) 04:35, 16 June 2010 (UTC)

So far not: Cell phone radiation, which is just electromagnetic radiation at about 0.5 to 3 GHz, has too few energy to modify molecules. That is also why normal light doesn't lead to cancer, either. Because it has about the same little radiation energy as cell phone radiation has. The calculation of the energy can be done with by multiplying the frequency with the Planck constant. Planck's_constant:

=> Frequency * 4.13566733(10)×10−15 eV/s = Radiation Energy

Hence, cell phone radiation has an energy of about 0.0000004 eV. And as long as the radiation energy is lower than circa 1 eV, someone's safe. :-) --MarS (talk) 20:54, 13 July 2010 (UTC)

"...ultimately to be absorbed by another body"[edit]

This is in the opening paragraph. I'm sure that radiation does not need to be "ultimately absorbed by another body" in order to be radiation. Maybe I'm missing something. PRONIZ (talk) 20:20, 28 July 2010 (UTC)

uncited text[edit]

The statement that radiation "...can result in changes to the natural environment" is uncited, and appears to be unnecessarily alarmist and misleading. In any case, without a cite it needs to be removed. Fell Gleamingtalk 22:14, 9 September 2010 (UTC)

Keep in mind that "radiation" is not just ionizing; "can" does not mean "will"; "changes" does not have a morality attached; and "natural environment" is not "rocks". I added citations.PRONIZ (talk) 22:59, 9 September 2010 (UTC)
There are some serious original research and Synthesis problems with your interpretion of your sources. Taking this one [4]. How is "Czochralski grown silicon" part of "the natural environment"? In the second source "Ecological Sorting during the Paleozoic Radiation of Vascular Plant Class", you were fooled by the word "radiation" in the title. It doesn't mean what you think it does. In the third source [5], there is nothing about radiation "changing the natural environment" either. The last link is not functioning at present. Based on this, I am removing the statement as uncited OR. Fell Gleamingtalk 01:17, 10 September 2010 (UTC)
Radiation, of all types, can change "things" - biological and non-biological. Could you please explain to me how you see this as "alarmist" or "misleading"? You also changed a sentence to read that high amounts of radiation can be harmful to organisms and you removed the bit about non-ionizing. For example, sunburns are due to non-ionizing radiation. Please don't revert my edits a 3rd time. I think you are confusing this article with the article on ionizing radiation. There are literally 1000's of scholarly articles on how radiation can change things. Please suggest a re-write here rather than deleting. Per WP:DR. PRONIZ (talk) 23:16, 10 September 2010 (UTC)

In Our Time[edit]

The BBC programme In Our Time presented by Melvyn Bragg has an episode which may be about this subject (if not moving this note to the appropriate talk page earns cookies). You can add it to "External links" by pasting {{In Our Time|Radiation|b00nqljy|Radiation}}. Rich Farmbrough, 03:19, 16 September 2010 (UTC).

Need brief explanation of induced radioactivity[edit]

I saw a segment a few hours ago on CNN where the anchors were confused about why people were concerned that radiation from the Fukushima I nuclear accidents could be carried by the wind. I'm pretty sure that the confusion stems from:

  • There is some equivocation between radiation and induced radioactivity (i.e. people don't realize that not all radiation will induce radioactivity), and
  • There's some confusion about what makes a material radioactive (related to the previous), and
  • Ignorance of induced radioactivity as a possible effect of radiation (on the part of those anchors, at least)

I think it'd be handy to explain those things here, but I'm not really familiar with where in the article they could go. —AySz88\^-^ 06:46, 15 March 2011 (UTC)

Only neutrons can induce radioactivity in otherwise stable materials. That's where it is explained. SkoreKeep (talk) 06:52, 23 February 2014 (UTC)

Nice illustration of radiation levels - public domain - unsure who/where to include[edit]

Just came across this really helpful graphic illustration comparing different radiation levels, in the spirit of Edward Tufte's work. But I do not know how or where to include it, and would welcome help: http://xkcd.com/radiation/DrMel (talk) 16:56, 30 March 2011 (UTC)

That graph seems unwieldy and I would present the same data in a more compact way, as a vertical, editable table (some data might change and wording might need correction). Materialscientist (talk) 08:17, 16 April 2011 (UTC)

X-ray wording[edit]

Ahhh! "X-rays are electromagnetic waves with a wavelength smaller than about 10 nanometres" needs to be changed to something like"X-rays are electromagnetic waves with a wavelength just smaller than 10 nanometres". 82.132.139.153 (talk) 07:58, 16 April 2011 (UTC)

These statements have two different meanings, and I think the former is correct. It says X-rays have a wavelength under approximately 10 nm; the latter says the wavelength is just under 10 nm, suggesting X-rays don't have a range of wavelengths (which they do). –CWenger (^@) 08:07, 16 April 2011 (UTC)
I hadn't thought about that. Oh well... 82.132.139.153 (talk) 08:30, 16 April 2011 (UTC)

saw a article about a guy who made a home made nuclear powerplant.[edit]

and he was arrested for breaking the "radiation safety law", however i can't find anything about it, and this seems to be the closest topic, but there doesnt seem to be a mention of against the law. or and what contrys if case be. — Preceding unsigned comment added by 217.8.130.17 (talk) 08:35, 23 August 2011 (UTC)

Try looking up "radioactive Boy Scout". SkoreKeep (talk) 00:55, 16 February 2014 (UTC)

Expanding on the top picture on radiation penetration[edit]

One often sees a representation of the alpha, beta and gamma ray penetrations but it would be neat if the other forms were also illustrated, notably neutron (fast and slow) 'flux' and perhaps even IR, UV, visible light, x-ray and neutrino to indicte the relative strengths.

It would be real interesting to show how some radiation results in more dangerous radiation after it has passed through solid (usually metal, sometimes lead) sheets (foils ?) as some x-ray energies do I seem to recall. Idyllic press (talk) 09:06, 14 November 2011 (UTC)

I think you are referring to Bremsstrahlung which refers to X-rays generated when beta radiation is quickly stopped. In laboratory settings, plexiglass or some other lower atomic number substance is used for beta shielding, instead of lead, to prevent this, more penetrating, X-ray production. PRONIZ (talk) 18:45, 14 November 2011 (UTC)
The trouble with such diagrams (including the one currently in use) is that the ability to penetrate depends as much on the energy the particle contains as it does the charge and mass. And the energy commonly varies over orders of magnitude. So a neutron could penetrate from perhaps an inch to several yards or more of concrete depending on the energy. Further, the penetration depths are Gaussian distributed (likely), and for a given average energy the penetration will be a distribution as well. Finally, while gammas are blocked by almost everything with density, less energetic EM gets picky about what they can penetrate and what they can't. Consider the absorption of different UV frequencies by atmosphere.
For example, an alpha can't penetrate a sheet of paper - everyone knows that. But an alpha from space can easily penetrate a human being. It would be nice if one size fit all, but it just doesn't. SkoreKeep (talk) 00:53, 16 February 2014 (UTC)