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pseudopad t1_iy324cy wrote

Reply to comment by TTTHD in ELI5: How are the Xray machines at airports not super dangerous? by Curious-Nothing6234

That's correct. The full body scanners use millimeterwave radiation that is non-ionizing (can't cause DNA damage) and barely gets deeper than your clothes.

The metal detectors don't use radiation at all, they use magnetic fields and detect changes in the field as metal passes through it.

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Malkiot t1_iy4b2nw wrote

Technically magnetic fields are also radiation and both scanners / detectors use electromagnetic radiation, albeit of different frequencies.

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Mand125 t1_iy4m4i5 wrote

They used to have some backscatter x-ray machines for full body scanning at some airports because federal contracting rules required two sources for scanners.

Since then they’ve been removed because any dose of x-rays is worth avoiding when you have the millimeter wave scanners available.

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No-Comparison8472 t1_iy78vlw wrote

Health hazard of EMF radiation is not just a matter of frequency. A laser can burn through the skin yet its frequency is usually a million times lower than the GHz found in these millimeterwave chambers.

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