[ RadSafe ] Airport Body Scanners

[Doug Huffman]

That is correct, millimeter wavelength, also known as "terahertz 
radiation" and "T-rays", and backscatter X-ray are used.

The dose from a backscatter X-ray airport body scan is estimated by the 
Health Physics Society at 0.005 milliREM (0.05 microSievert) and 0.009 
milliREM (0.09 microSievert) by the manufacturer of one such device, 
American Science and Engineering.  1 milliREM is considered a negligible 
dose equal to two hundred such Health Physics Society scans.

Millimeter waves are reflected off clothing according to some sources. 
In any case, the energy of such a photon is insufficient to break a 
chemical bond or ionize an atom.

Unfortunately this is received knowledge from public sources and no more 
believable to the doubter than the empirical knowledge from which it is 
derived.

On 3/7/2010 10:36, Ed Hiserodt wrote:
>> "Regarding the virtual strip-search machines that will be appearing at
> airports across the country, how much radiation do they actually release and
> how does this compare to the radiation we are normally exposed to anyway?
> How dangerous are these machines, if at all, for someone who does a lot of
> flying?  I understand that there are two technologies the TSA uses to peer
> through clothing:
>
> "One uses millimeter waves - does this involve any radiation; is it
> completely safe?  > "The other is the backscatter X-ray."
>
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