One of my customer's is interested in feedback from other companies regarding incoming inspection as follows: Any responses would be most appreciated and will be sent to them. 1) What would a normal telecommunications industry AQL and sampling plan be for a company that has contractual obligations to meet Bellcore's TR-NWT-000078 and that uses IPC-A-600, class 2, as an inspection criteria for printed wiring boards? This company also wishes to use a reduced labor sampling plan. 2) Example: Items being inspected at Incoming Inspection are printed wiring boards. They are inspected to Bellcore TR'78 and IPC-A-600, class 2. The company inspection methodology is that a single manufacturing process defect found on one board out of the sample group (e.g. qty. 9) will cause the entire lot of boards (e.g. qty. 5,000) to be rejected. Is this proper taking into consideration that there can be hundreds of electrical nets per board and the defect (say, a circuit width reduction of 80%) has occurred to only one of the 9 sample boards' circuit runs? If rejecting the lot based upon finding this one defect on one sample board is too stringent, what would be more reasonable? How many defects of a particular kind should be found across the samples before the defect can be considered a seriously systemic process issue? Is there a statistical way of determining this? Carrie Lawn HADCO Corporation *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To subscribe/unsubscribe send a message <to: [log in to unmask]> * * with <subject: subscribe/unsubscribe> and no text in the body. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************