The "block of dense material" can be made to look like ordinary items.
The Xray can show organic material in a different color but there are lots of things, other than explosives, that will show up as organic.
The new checked bag screening machines are the best technology we currently have available. They do what no other current technology can do which is to quickly clear large quantities of checked bags which greatly reduces the number of bags which need additional attention.
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Spiff:
When there is a large block of dense, material, do you think the screeners will just pass it because they don't see a gun?
Explosives also give off a different colored signature on the x-ray. The newer CT EDS machines that the TSA is blowing billions of dollars on might have better resolution were it not for the 30% false-positive rates and unknown false-negative rates.
But of course you knew both of these things too and just chose to ignore them as well...
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