Old Jun 25, 19, 8:15 am
  #462  
GUWonder
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Join Date: Jul 2001
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Originally Posted by gooselee View Post
I feel like I once learned that WTMDs scan in vertical zones. If I'm wearing a heavy watch, I will walk through the metal detector with that wrist across my chest (basically looks like I'm scratching my opposite shoulder as I'm walking through). This raises the metal in my watch up and away from my lower body where my wallet and belt are.

In my very unscientific testing when I learned about this - I used the ATL PreCheck checkpoint three times in the course of a week. Literally the same line and WTMD each time. Same shoes, belt, watch, wallet. Similar clothing (jeans and a polo shirt). WTMD alarmed the first time when I walked through normally and I had to dump my watch into my bin (which thankfully was still on the conveyor thing). Did not alarm the next two times when I raised my watch hand up.
Most WTMDs scan based on vertical zones. Also some WTMDs have indicators showing which vertical zone was triggered when the passenger walk-thru alarmed the machine.
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