How is that accomplished? I know sometimes when I go through the security line they take a white, circular pad, wipe my laptop, bag, etc. and put the pad in a sensor.
Do they do this with every piece of luggage going into the hold?
My carry on is randomly swiped for chemical residue.
Leave X-ray, asked for chemical residue test, proceed to counter, open bag let them swipe the cloth in my clothes a little, and then the inside of my bag a little as well, test passes and I zip my carry on back up and I'm on my way to the gate. This is pretty routine when flying in Australia. I'm pretty sure we stared doing this for catching drugs and regular non terrorist illegal stuff in the 90s or even earlier, and just decided it was a sensible idea to buy stuff that can also detect explosives as well.
Do they do this with every piece of luggage going into the hold?