Righto fella (aka clean32) I don't beleive it matters but you seem to.
No I don't travel as frequently as you BUT i have travelled on a lot of different airlines in all bar one continent on the planet, to over 30 countries at various times - so yes I do have a bit of "experience". Happier now?
Let's look at your comment where you said
I can confidently say you are showing a lack of knowledge (a.k.a. You are full of it).
I have direct experience.
I have handled firearms during my work, shortly prior to travel.
I have handled firearms when packing and clearing them privately, prior to shipping them by air.
I have frequently been the 'random" person chosen for the swabs.
I have NEVER, repeat NEVER had a positive reading on these machines.
Why ? Because they aren't generally set up to test for the major components in gunpowder - as these are very low risk. The machines have a limitation as to how many channels can be programmed - that is, how many substances they can recognise Therefore they are programmed with substances that are higher risk.. explosives mainly.
Barringer (Smiths) is the major player in the industry and these are the common instruments.
Smiths Detection - IONSCAN 500DT
Smiths Detection - IONSCAN 400B
Also you are confused as the "full body scans" you are referring to and the "chemical scans" are different in purpose. What you refer to as a chemical scan is in fact substance detection using a technology known as
Ion mobility spectrometry. A swab is wiped on the area to be tested - say your shirtsleeves, then placed in the machine for analysis.
Moe on IMS:
Ion mobility spectrometry - Wikipedia, the free encyclopedia
The body scans, on the other hand use low dose radiation (millimetre-wave) to see through your clothes (in laymans terms). The intention is to detect any item (guns, knives, explosives etc) concealed on or about the body.
Here's one example
Smiths Detection - eqo
So as you can see the two are entirely different in purpose, not alternatives to one another.
Hope this helps

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