RYR738_driver
How does that work???
The sensitivity of metal detection units in the UK seems to vary greatly. When visiting my mother in the Isle of Man, my clothing would not trip the detector at Luton but the same boots on the return journey - would. This was before removing shoes was standard.
I used to comment to the operator that their scanner was set to a lower threshold than the one at Luton. They replied (emphatically) that was not the case and that all arches were set the same in the UK. I made a point of asking about the scanner settings once a year and always got the same reply. Across the 25 years that my mother lived in the island, that was plainly not true and the IOM set theirs more 'sharply'.