Metal detector checking procedures shall be based on best good practice and shall as a minimum include:
• use of test pieces incorporating a sphere of metal of a known diameter selected on the basis of risk. The test pieces shall
be marked with the size and type of test material contained.
• tests carried out using separate test pieces containing ferrous metal, stainless steel and typically non-ferrous metal -,
unless the product is within a foil container where Ferrous only may be applicable.
• a test that both the detection and rejection mechanisms are working effectively under normal working conditions.
• checks that test the memory/reset function of the metal detector by passing successive test packs through the unit at
typical line operating speed.