when auditing in process line 3 in a clothing manufacture, the auditor notices that a metal detector is located above the conveyor belt just before the clothing is packed for being packed with the clothes, The auditor asds how this device is calibrated and is told that a test piece is put through on the coveyor each morning before production starts. A check of the current production record appears to confirm this since the box titled "MD"check is signed and marked with today's date. The Production manager confirm he signature belongs to the production supervisor. the auditor asks to see the test piece used to calibrate the device and shown the top of a tin can. The top is about 00mm in diameter and marked "MD Test item 4" The Production manager cofirm that the detector had not found any metal contaminants as far as he knew.