Sop of challenge test of metal detector

Test coin like ferrous , non-ferrous and stainless steel made by which metal?

Prepare a test set of tablets with known contamination with stainless steel or iron
wires or balls (e.g., used as sieve material for an oscillating granulator or a milling
machine). Pass these tablets (falling free, directed through the center of the detector
area, or directed along the side of the detector area) at the different adjustable
sensitivity levels through the metal check device and document whether the device
is approving or withdrawing the tablets. Determine the warm-up time of the device
necessary to receive a constant device sensitivity.
(validation SOP)
Syed Imtiaz Haider, Ph.D.

made of acrylic

what is the dimension of metal detector. ?