3 ms·

That's for the X-ray backscatter scanners; millimeter-wave scanners are in common use in the US as well, and are safe as far as we know.

SoftwareMaven 15y ago
"as far as we know" Is there good, unbiased evidence of that? I don't trust the manufacturers nor the government, but I also don't believe because electromagnet waves are involved, it is inherently toxic.
- joe42 15y ago
  X-rays have enough energy to break molecular bonds in your body (ionizing radiation), millimeter waves do not.
  - libraryatnight 15y ago
    Is there a way, at a glance, to recognize x-ray vs millimeter machines?
    - jchrisa 15y ago
      Even if there is, I'm guessing it would be hard to tell at a glance whether the machine was calibrated by someone with a physics degree or someone who'd be delivering pizzas if it weren't for the growth of the security industry.
    - hammock 15y ago
      In the US, the backscatter x-ray machines are two giant ugly blue boxes that you stand between. The mm wave machines are more futuristic-looking, white cylinders that you stand inside of. (photos here http://www.flyertalk.com/forum/practical-travel-safety-issues/1138014-complete-list-airports-whole-body-imaging-advanced-imaging-technology-scanner.html http://www.flyertalk.com/forum/practical-travel-safety-issue...) The technology deployment is airport-specific, so you will only find one or the other at any given airport, e.g. O'Hare uses Backscatter, Midway uses mm wave. La Guardia is the one airport serving a major US city that does not have any of the new scanners, which can be nice if you typically opt-out.
      - libraryatnight 15y ago
        Thank you, this is very useful.
    - shallowwater 15y ago
      I can in no way substantiate this, but the xray ones are usually two large (maybe always blue?) mostly rectangular blocks that you stand in between. The millimeter machines are usually rounder and have clear bits. The illustrations here might help: http://www.jaunted.com/story/2010/1/5/163631/3181/travel/Full-Body+Scanners+101%3A+The+Two+Types+and+How+They+Work http://www.jaunted.com/story/2010/1/5/163631/3181/travel/Ful... edit: never mind, the flyer talk pics are much better.
- frig8 15y ago
  Currently deployed scanners operate in the 24-30 GHz range. Generally, microwave radiation is considered safe as long as it's not intense enough to cause burns. http://en.wikipedia.org/wiki/Microwave#Health_effects http://en.wikipedia.org/wiki/Microwave#Health_effects
benmccann 15y ago
There are X-ray backscatter scanners in use in the U.S. For example, they are used in San Jose airport, which is probably the airport most used by HN readers.

SoftwareMaven 15y ago

"as far as we know" Is there good, unbiased evidence of that? I don't trust the manufacturers nor the government, but I also don't believe because electromagnet waves are involved, it is inherently toxic.

joe42 15y ago
X-rays have enough energy to break molecular bonds in your body (ionizing radiation), millimeter waves do not.
- libraryatnight 15y ago
  Is there a way, at a glance, to recognize x-ray vs millimeter machines?
  - jchrisa 15y ago
    Even if there is, I'm guessing it would be hard to tell at a glance whether the machine was calibrated by someone with a physics degree or someone who'd be delivering pizzas if it weren't for the growth of the security industry.
  - hammock 15y ago
    In the US, the backscatter x-ray machines are two giant ugly blue boxes that you stand between. The mm wave machines are more futuristic-looking, white cylinders that you stand inside of. (photos here http://www.flyertalk.com/forum/practical-travel-safety-issues/1138014-complete-list-airports-whole-body-imaging-advanced-imaging-technology-scanner.html http://www.flyertalk.com/forum/practical-travel-safety-issue...) The technology deployment is airport-specific, so you will only find one or the other at any given airport, e.g. O'Hare uses Backscatter, Midway uses mm wave. La Guardia is the one airport serving a major US city that does not have any of the new scanners, which can be nice if you typically opt-out.
    - libraryatnight 15y ago
      Thank you, this is very useful.
  - shallowwater 15y ago
    I can in no way substantiate this, but the xray ones are usually two large (maybe always blue?) mostly rectangular blocks that you stand in between. The millimeter machines are usually rounder and have clear bits. The illustrations here might help: http://www.jaunted.com/story/2010/1/5/163631/3181/travel/Full-Body+Scanners+101%3A+The+Two+Types+and+How+They+Work http://www.jaunted.com/story/2010/1/5/163631/3181/travel/Ful... edit: never mind, the flyer talk pics are much better.
frig8 15y ago
Currently deployed scanners operate in the 24-30 GHz range. Generally, microwave radiation is considered safe as long as it's not intense enough to cause burns. http://en.wikipedia.org/wiki/Microwave#Health_effects http://en.wikipedia.org/wiki/Microwave#Health_effects

benmccann 15y ago

There are X-ray backscatter scanners in use in the U.S. For example, they are used in San Jose airport, which is probably the airport most used by HN readers.