If I had to face security screening three or four times a day, every day, I think I would explode, no explosives needed.
I had to go through in a hurry at Melbourne last week to meet a Son that had a life threatening infection to get him straight to Hospital.
I had to bite my tongue as the little Indian/Pakistani/ Sri Lankan security clown tried to explain to Three Chinese ladies in front of me about removing metalwork, then my belt buckle set everything off, so it was back and forth about Four effing times.
As for "explosive residue" what an effing stupidity! I have an Army surplus bag that I use occasionally. It has traces of "explosive residue" on it because it was effing well used to carry effing explosives! Personally, I, and all of my clothes, will reek of effing "explosive residue" if, the day before a flight, I've spent the morning at the rifle range, as I sometimes do.
And to what purpose? Bruce Schneir the American Security expert, has just condemned this whole pile of crap as pointless "Security theatre".
The Things He Carried - The Atlantic (November 2008)
Furthermore, there are other, major, gapingly wide holes in Airport security that go totally and completely unplugged that I will not detail here..