Metal detector triggers??

Question

I go to the airport 2 times a months, and I still cant figure out what actually sets off a metal detector, the list as following

Metal shoe shank = yes (steel???)

coins in pocket= no

Piercings= no (surgical steel)

keys = yes

metal buttons on jacket = no

yet to try more objects....

what substance/amount of substance actually sets off a metal detector!?!?!?!?

Answer 1

metal shoe= yes(your gonna have to take off you shoe anyways)

coins= yes, that's why you have to put it in the basket

piercings=probrobly not

keys=yes

metal button= prob. not.

Answer 2

Anything metal will could set it off--hence the term "metal detector".  It makes no difference what the metal is.  It will pick up all of the items above.

As for what amount of metal it takes to set on off, that depends.  The detector can be set to different sensitivities.  Airport metal detectors vary greatly over time and between different airports.    I've noticed that the more potential there is for a threat, the more sensitive they're set.  For example, immediately after 9-11, most detectors were so sensitively set I thought they'd pick up the fillings in my teeth. :o)  Lately, though, as long as I don't have change in my pockets, a big belt buckle, & my big metal watch on, I have no problem getting through with a necklace, a couple of rings, and a hairclip.  I remember times when that was not the case, and *everything* short of the zipper & buttons on my jeans would set it off.  (On a particularly embarrassing time, it was the underwires in my bra that set it off!!!)

So, it's no surprise you can't figure out exactly how much metal you can get by with-- the machines are probably set at least slightly differently every time you go through.