7 ms·

Backscatter x-ray technology was removed from airports. [1] All airports now use millimeter wave technology. [2] [1] https://en.wikipedia.org/wiki/Backscatter

Backscatter x-ray technology was removed from airports. [1] All airports now use millimeter wave technology. [2] [1] https://en.wikipedia.org/wiki/Backscatter_X-ray https://en.wikipedia.org/wiki/Backscatter_X-ray [2] https://en.wikipedia.org/wiki/Millimeter_wave_scanner https://en.wikipedia.org/wiki/Millimeter_wave_scanner

jamoes 12y ago
Millimeter wave scanners still subject the body to radiation, even though they don't have the work "X-Ray" in the name. Radiation damage to your body is cumulative throughout your life, so if you care about your longevity, you'd be wise to opt-out of subjecting your body to this radiation whenever possible.
- darkmighty 12y ago
  Note that this view of "cumulative ratiation" is a myth, and a costly one. A recent note on this: http://atomicinsightscom.c.presscdn.com/wp-content/uploads/Cuttler-2014_-Leukemia-incidence-of-96000-Hiroshima-survivors_ArchToxicol.pdf http://atomicinsightscom.c.presscdn.com/wp-content/uploads/C... (there's not only a treshold, there may also be some hormesis, i.e. a slight decline in cancer rate for small doses)
  - lvs 12y ago
    This one page paper with one figure and six data points from an author nobody knows in a journal nobody has heard of is right. The generally accepted models of radiation dose must be thrown out the window.
- CamperBob2 12y ago
  Sigh. Using bullshit to argue against bullshit just leaves the whole world shittier.
- toufka 12y ago
  Millimeter wave scanners are of an entirely different kind of 'radiation' than backscatter X-rays in the same way 'red light' is of a different kind of radiation from 'alpha particles'. Yes, technically they are are the "radiation" of an emitted particle from an interaction. But they are of significantly, quantitatively, and oncogenically different kinds of 'radiation'. Backscatter X-ray radiation is of very high intensity and almost certainly can cause damage to biological surface tissue. Millimeter wave uses non-ionizing radiation - it does not have the capability of causing what we generally refer to when we speak of biological damage by radiation. It might do something else - though this seems to be debatable, and largely hypothetical, it is simply incapable of the damage that a backscatter X-ray machine could realistically cause. Here's the letter authored by significant scientists written to the White House in regards to their thoughts on the backscatter machines [1]. [1] http://www.ucsf.edu/sites/default/files/legacy_files/concern.pdf http://www.ucsf.edu/sites/default/files/legacy_files/concern...
- tedunangst 12y ago
  A light bulb subjects the body to radiation.
  - jamoes 12y ago
    A light-bulb's light also doesn't penetrate solid objects. It's clearly a different type of radiation than standard light. Our bodies aren't subject to millimeter wave radiation in nature, so they're not really evolved to defend against it. I'm not against further studies of millimeter wave radiation and its effects on humans, I just don't want to be a guinea pig in those studies.
    - deleted 12y ago
      [deleted]
    - UrMomReadsHN 12y ago
      That's not how evolution works...
    - SomeCallMeTim 12y ago
      Umm...glass is a "solid object" the last time I checked. And no, it's electromagnetic radiation, period -- it's a different wavelength (just like blue is a different wavelength than red). Look for the reply from the physicist for greater detail as to why you're completely confused, though. I opted out of the Backscatter X-Ray machines due to what seemed like poor science; the MM wave devices may violate privacy, but that's their worst offense.
      - shard 12y ago
        To be fair, Jamie's is probably thinking of the human body. However, even in that case, you can see that light goes through the human body by holding a flashlight against your palm and seeing the glow on the back side of your hand.
- lvs 12y ago
  No, there is ionizing radiation and nonionizing radiation. X-rays are ionizing radiation with photon energies higher than visible light. THz RF radiation is nonionizing and has photon energies that are less than that of visible light.
- drostie 12y ago
  So you've got a bunch of responses, but as a guy with a Master's in applied physics I wanted to chime in with a bit more of a long explanation. The word "radiation" just means that something radiates -- it travels off to infinity. In this case we're talking about electromagnetic radiation, which spans a vast continuum from radio waves through microwaves to infrared and red, across the visible spectrum to deep blue, then on into ultraviolet, X-ray, and gamma light. It turns out that this radiation is quantized -- meaning it comes in lumps of a certain energy E = hf where h is a fundamental constant and f is the frequency of the light (equivalently, f = c / L where L is the wavelength). Light also comes with a certain "kick" or momentum p = E / c. We knew the latter formula from classical electromagnetism but the former formula was awarded two Nobel prizes, one to Max Planck and one three years later to Albert Einstein. It is presently thought that the blue side of the non-visible electromagnetic radiation spectrum (UV, X-rays, Gamma rays) is cancer-causing, while the visible and red-side of nonvisible is not. This comports with the Planck/Einstein law for the energy of the photons, which approaches the bond energies for several common atomic bonds in the visible spectrum and exceeds it as we go into the ultraviolet. (We essentially see light by having the light excite these bonds, but not so much that it tears them apart, so as they "relax" to their starting configuration they release the energy and activate neurons.) Microwaves are about 1mm or 1cm long, on the red side. They are emitted by microwave ovens, cell phones, wifi hotspots, and millimeter-wave detectors. Right now it's not thought that these are "dangerous" radiation any more than white light is, because their "kicks" don't excite the atomic bonds but are instead absorbed by proteins as a whole, in a process we presently think is indistinguishable from any other sort of heat transfer. That is, they heat you up, but don't do much else. If they did something else, probably very large changes would have to be made to our modern scientific understanding, which I of course would totally support if experiments bore it out. At present there are no good experiments which show any other effects of microwaves on biological tissue, other than the heating thing.
  - thinkling 12y ago
    I like this response a lot and am going to adapt it to explain this to my radiation-paranoid family. The concept of wavelength as the sole distinction between these types of radiation is probably abstract to most non-science-educated people. Can you (or anyone else) think of a good concrete real-world analogy of different types of X that vary only in Y and some X are harmless but those with Y are not? Maybe an analogy of throwing sand at someone vs. shooting a bullet?
- pdonis 12y ago
  If you're worried about this, you shouldn't fly at all. The amount of radiation your body is exposed to during the flight is several orders of magnitude larger than the amount it's exposed to during the security screening. Not only that, the radiation you're exposed to during the flight is higher energy (cosmic rays are the major component) and can do more damage to your body than the microwaves used in the security scanners.

jamoes 12y ago

Millimeter wave scanners still subject the body to radiation, even though they don't have the work "X-Ray" in the name. Radiation damage to your body is cumulative throughout your life, so if you care about your longevity, you'd be wise to opt-out of subjecting your body to this radiation whenever possible.

darkmighty 12y ago
Note that this view of "cumulative ratiation" is a myth, and a costly one. A recent note on this: http://atomicinsightscom.c.presscdn.com/wp-content/uploads/Cuttler-2014_-Leukemia-incidence-of-96000-Hiroshima-survivors_ArchToxicol.pdf http://atomicinsightscom.c.presscdn.com/wp-content/uploads/C... (there's not only a treshold, there may also be some hormesis, i.e. a slight decline in cancer rate for small doses)
- lvs 12y ago
  This one page paper with one figure and six data points from an author nobody knows in a journal nobody has heard of is right. The generally accepted models of radiation dose must be thrown out the window.
CamperBob2 12y ago
Sigh. Using bullshit to argue against bullshit just leaves the whole world shittier.
toufka 12y ago
Millimeter wave scanners are of an entirely different kind of 'radiation' than backscatter X-rays in the same way 'red light' is of a different kind of radiation from 'alpha particles'. Yes, technically they are are the "radiation" of an emitted particle from an interaction. But they are of significantly, quantitatively, and oncogenically different kinds of 'radiation'. Backscatter X-ray radiation is of very high intensity and almost certainly can cause damage to biological surface tissue. Millimeter wave uses non-ionizing radiation - it does not have the capability of causing what we generally refer to when we speak of biological damage by radiation. It might do something else - though this seems to be debatable, and largely hypothetical, it is simply incapable of the damage that a backscatter X-ray machine could realistically cause. Here's the letter authored by significant scientists written to the White House in regards to their thoughts on the backscatter machines [1]. [1] http://www.ucsf.edu/sites/default/files/legacy_files/concern.pdf http://www.ucsf.edu/sites/default/files/legacy_files/concern...
tedunangst 12y ago
A light bulb subjects the body to radiation.
- jamoes 12y ago
  A light-bulb's light also doesn't penetrate solid objects. It's clearly a different type of radiation than standard light. Our bodies aren't subject to millimeter wave radiation in nature, so they're not really evolved to defend against it. I'm not against further studies of millimeter wave radiation and its effects on humans, I just don't want to be a guinea pig in those studies.
  - deleted 12y ago
    [deleted]
  - UrMomReadsHN 12y ago
    That's not how evolution works...
  - SomeCallMeTim 12y ago
    Umm...glass is a "solid object" the last time I checked. And no, it's electromagnetic radiation, period -- it's a different wavelength (just like blue is a different wavelength than red). Look for the reply from the physicist for greater detail as to why you're completely confused, though. I opted out of the Backscatter X-Ray machines due to what seemed like poor science; the MM wave devices may violate privacy, but that's their worst offense.
    - shard 12y ago
      To be fair, Jamie's is probably thinking of the human body. However, even in that case, you can see that light goes through the human body by holding a flashlight against your palm and seeing the glow on the back side of your hand.
lvs 12y ago
No, there is ionizing radiation and nonionizing radiation. X-rays are ionizing radiation with photon energies higher than visible light. THz RF radiation is nonionizing and has photon energies that are less than that of visible light.
drostie 12y ago
So you've got a bunch of responses, but as a guy with a Master's in applied physics I wanted to chime in with a bit more of a long explanation. The word "radiation" just means that something radiates -- it travels off to infinity. In this case we're talking about electromagnetic radiation, which spans a vast continuum from radio waves through microwaves to infrared and red, across the visible spectrum to deep blue, then on into ultraviolet, X-ray, and gamma light. It turns out that this radiation is quantized -- meaning it comes in lumps of a certain energy E = hf where h is a fundamental constant and f is the frequency of the light (equivalently, f = c / L where L is the wavelength). Light also comes with a certain "kick" or momentum p = E / c. We knew the latter formula from classical electromagnetism but the former formula was awarded two Nobel prizes, one to Max Planck and one three years later to Albert Einstein. It is presently thought that the blue side of the non-visible electromagnetic radiation spectrum (UV, X-rays, Gamma rays) is cancer-causing, while the visible and red-side of nonvisible is not. This comports with the Planck/Einstein law for the energy of the photons, which approaches the bond energies for several common atomic bonds in the visible spectrum and exceeds it as we go into the ultraviolet. (We essentially see light by having the light excite these bonds, but not so much that it tears them apart, so as they "relax" to their starting configuration they release the energy and activate neurons.) Microwaves are about 1mm or 1cm long, on the red side. They are emitted by microwave ovens, cell phones, wifi hotspots, and millimeter-wave detectors. Right now it's not thought that these are "dangerous" radiation any more than white light is, because their "kicks" don't excite the atomic bonds but are instead absorbed by proteins as a whole, in a process we presently think is indistinguishable from any other sort of heat transfer. That is, they heat you up, but don't do much else. If they did something else, probably very large changes would have to be made to our modern scientific understanding, which I of course would totally support if experiments bore it out. At present there are no good experiments which show any other effects of microwaves on biological tissue, other than the heating thing.
- thinkling 12y ago
  I like this response a lot and am going to adapt it to explain this to my radiation-paranoid family. The concept of wavelength as the sole distinction between these types of radiation is probably abstract to most non-science-educated people. Can you (or anyone else) think of a good concrete real-world analogy of different types of X that vary only in Y and some X are harmless but those with Y are not? Maybe an analogy of throwing sand at someone vs. shooting a bullet?
pdonis 12y ago
If you're worried about this, you shouldn't fly at all. The amount of radiation your body is exposed to during the flight is several orders of magnitude larger than the amount it's exposed to during the security screening. Not only that, the radiation you're exposed to during the flight is higher energy (cosmic rays are the major component) and can do more damage to your body than the microwaves used in the security scanners.