Hello, was on Elsmar's some time ago, quiet disappointment to see that its gone. Nice though to have a backup here Maybe You could help me with this problem: We recently had an ISO 9001 audit at our camshaft and the auditor found one non conformance: We use several manual measuring tools at SPC stations (simple OK/NOK tests), and one tool was found to be out of tolerance at the yearly calibration. The auditor still asks us how we can be sure that the parts we produced since the last measuring tool calibration were all ok (since we don't now when it was damaged enough to be out of tolerance). Since we do weekly 100% measurements on our CMMs as double check it would have been detected earlier if NOK parts were being produced, also no customer complaints about this specific feature ever. Still the auditor is not satisfied. Sounds like he wants to see some process if a situation like this ever happens again, or a different way to check the measurement tools. But You can't cut the intervalls down indefinetly, there will always be some time frame where You will be unsure what happened if You find out one measurement tool is out of tolerance. Any idea how to solve this (sounds liks a riddle to me actually)?