Regardless of who calibrates the wands or the WTMDs, prior to 9/11 I could walk through a WTMD with a few coins, my pocket knife, and a few keys and I don't recall my pants clasp (note not belt buckle, pants clasp) setting of the wand. Now (well, actually 2001-2002, as I haven't alarmed a WTMD since) anything more than my glasses (titanium), watch (small aluminum backplate), and pants (oft-mentioned clasp, plastic zipper) will set off the WTMD, including one-nickel and/or dime. I'm pretty sure the CC's in my wallet are sometimes enough to set it off too; haven't tried recently and don't plan to. Women here report that their bras also did not set off the wand; personally I have no first-hand experience in that arena The prior calibration made sense if the targeted items were guns, medium-large knives, etc.

It makes sense that these were recalibrated when screening assumed the (misguided) mandate of finding tiny and pointy non-threatening objects (jewler's screwdrivers, small pocket knifes, etc.) because without raising the WTMD and HHMD settings above where they were, I could waltz right through the WTMD (but not scoot or high-step!) carrying these items and never be subject to secondary screening to find the objects.

If the prohibited items list were reduced to include only (larger) threatening objects, the WTMD and HHMD's could be reconfigured resulting in far fewer secondary screenings and (probably) far fewer complaints against screeners. My guess is that one of the many (flawed) reasons this will never happen is it would reduce the number of screeners needed, and federal agencies don't like to shrink themselves.