Radiation from cellphones/laptops/etc.

[W|M]

Radiation that doesn't free electrons from atoms, which is what ionization is. Non-ionizing radiation includes things like radio waves, microwaves and visible light, and is generally harmless

 

[Timsup2nothin]

Radiation that doesn't free electrons from atoms, which is what ionization is. Non-ionizing radiation includes things like radio waves, microwaves and visible light, and is generally harmless

So it is circumstantial, since under the right circumstances radio waves, microwaves, or visible light can free electrons from atoms. I think what the intention was is that lower energy radiation, such as radio waves, microwaves, and visible light, is less damaging than higher energy radiation. I just don't like the false dichotomy of ionizing/non-ionizing.

 

[W|M]

No, they can't; Microwaves, visible light and radio waves will never be able to free an electron from an atom

 

[Arakhor]

Well, actually there was the rather famous bother with the photoelectric effect, where visible light did dislodge electrons from a strip of metal, proving that light is not a wave and is in fact a collection of particles now called photons, but that effect is down to frequency (i.e. the energy of the particles) and not the intensity of the light or the length of exposure.

 

[uppi]

Hold up...what is this "non-ionizing" radiation?

Radiation that does not carry enough energy per photon to immediately ionize most materials.

 

[uppi]

No, they can't; Microwaves, visible light and radio waves will never be able to free an electron from an atom

Wrong. You just need enough of it. You can create a plasma with non-ionizing radiation.

 

[Timsup2nothin]

No, they can't; Microwaves, visible light and radio waves will never be able to free an electron from an atom

Obviously not posted from a device plugged into an outlet powered by solar.

 

[Timsup2nothin]

Radiation that does not carry enough energy per photon to immediately ionize most materials.

That "most" makes a pretty subjective definition, which I think is why I just didn't like the term in the first place. If there was a specific but arbitrary energy level and everything below it was called "non-ionizing" even though it might that would be even worse. Overall, I think this is one of those "layman's term simplifications" I can just do without.

 

[uppi]

That "most" makes a pretty subjective definition, which I think is why I just didn't like the term in the first place. If there was a specific but arbitrary energy level and everything below it was called "non-ionizing" even though it might that would be even worse. Overall, I think this is one of those "layman's term simplifications" I can just do without.

The exact threshold is of course subjective, but there can be no debate that it is in the PHz-range. If you are talking about frequencies much higher or lower than that, it is clear in which category they belong to and there is a significant difference when you talk about biological damage.

 

[Manfred Belheim]

Obviously not posted from a device plugged into an outlet powered by solar.

I believe solar panels are semi-conductors and their operation doesn't involve being ionised by light. They most likely don't work if you shine microwaves or radio waves on them either to be fair.

 

[Timsup2nothin]

I believe solar panels are semi-conductors and their operation doesn't involve being ionised by light. They most likely don't work if you shine microwaves or radio waves on them either to be fair.

Photo-voltaic effect is definitely an ionization process. The semiconductor junction directs? collects? well, somehow it makes the freed electrons go where they are intended to go...but it is definitely using visible light as "ionizing radiation."

Uppi hit the major point, in that if the context is "biological damage" than the circumstances of the ionization that matters are pretty limited. Obviously a panel made of material that is specifically made to be ionized by visible light doesn't fit that context.

Back in the day, when I was required to wear dosimetry to monitor my exposure, this was all somewhat of an issue. How the monitor counts incidence has to be weighed against the expected energy levels present. If you are working with a Co-60 source and the dosimeter counts a certain number of interactions that can be a significantly different indication of biological damage than the same number of interactions if you are are working with sustained exposure to N-16...I chose those as examples because my exposure calculations were based on "well, he'll get some mix of these, mostly, so we'll count it as this wildly guessed at mixture."

So the problem with this "ionizing" vs "non-ionizing," in my opinion, is that it obscures the important question "just how ionizing are we talking about here?"

 

[Arakhor]

I always thought that "microwave" was a silly name, given that they can have wavelengths of anything up to a metre long and would be eminently apparent to the naked eye, if only they radiated visible light.

 

[Manfred Belheim]

Photo-voltaic effect is definitely an ionization process. The semiconductor junction directs? collects? well, somehow it makes the freed electrons go where they are intended to go...but it is definitely using visible light as "ionizing radiation."

Well, it's been a while since I studied any of this, and I don't remember ever specifically learning anything about how solar panels themselves work, but as far as I'm aware there's no ionisation involved, because no ions are created. You just get electrons promoted into the ̶v̶a̶l̶e̶n̶c̶e̶ conduction band of the material so they can act as charge carriers, but they don't shoot off into the ether. I'm obviously not claiming to be an authority though.

 

[Timsup2nothin]

Well, it's been a while since I studied any of this, and I don't remember ever specifically learning anything about how solar panels themselves work, but as far as I'm aware there's no ionisation involved, because no ions are created. You just get electrons promoted into the ̶v̶a̶l̶e̶n̶c̶e̶ conduction band of the material so they can act as charge carriers, but they don't shoot off into the ether. I'm obviously not claiming to be an authority though.

Hmmmm...I guess this qualifies as the extreme of circumstantial. If it weren't for the semiconductor junction I guess there wouldn't be ionization, but in this case the charge carriers, while they don't "shoot off into the ether" are definitely stripped off to produce the output current. Eventually they do make their way back, through whatever circuitry, so I dunno if that counts as ionization.

Better use of terms: the decisive factor is "ionizing (or non-ionizing) in tissue."

 

[Manfred Belheim]

Well no, because the electrons are still bound to the material, and are still essentially part of the "molecule" of the whole chunk of the semi-conductor. So that's not ionisation. The same way electrons are entirely free to move around in the body of a chunk of metal. I guess it's kind of like a boat being moored up, being pushed off so it can float down the river freely, or being blasted out of the water entirely an air-to-ground missile. Ionising radation is like the air-to-ground missile. You can still move the boat without firing a missile at it, but only the missile will give it cancer. Or something.

 

[Perfection]

Wrong. You just need enough of it. You can create a plasma with non-ionizing radiation.

Correct me if I'm wrong but radiation itself wouldn't be doing the ionizing, it would just be raising the temperature until you reach the point where it becomes plasma.


Anyways, visual light is by far most harmful form of electromagnetic radiation coming out of your laptop or cell phone - in particular it can harm your sleep/wake cycles, cause eye strain etc.

 

[Manfred Belheim]

Correct me if I'm wrong but radiation itself wouldn't be doing the ionizing, it would just be raising the temperature until you reach the point where it becomes plasma.

So if I stand in a microwave beam long enough so that it turns me into a plasma, I might get cancer?!?

Anyways, visual light is by far most harmful form of electromagnetic radiation coming out of your laptop or cell phone - in particular it can harm your sleep/wake cycles, cause eye strain etc.

I think cancer > sleep cycles and eye strain though.

 

[W|M]

If you're hot enough to become plasma, you might have other things to worry about

 

[TheMeInTeam]

So if I stand in a microwave beam long enough so that it turns me into a plasma, I might get cancer?!?



I think cancer > sleep cycles and eye strain though.

You will get dead . Any cancer cells would die too though. It's pretty effective in that regard!

 

[Arakhor]

I think cancer > sleep cycles and eye strain though.

On sheer "badness" stakes, certainly, but the latter two are much more pervasive and improper sleep for protracted periods leads to all sorts of other issues.