Hi Bernhard, I think this should work in general, but bew advised that these specs are written by committees and thus may represent the lowest common denominator. Depending on what kind of products you build, and who builds the PVBs and the assemblies, you may want to impose additional details. Also, none of the spec's cited contain any reliability information; at the design stage you should list IPC-D-279. It contains "ONLY" guidelines (reliability can not really be spec'd except perhaps as an end requirement--and then you have the problem of confirming it with some accelerated testing), but if followed it goes a long way in assuring the reliability of your products. Werner Engelmaier Engelmaier Associates, L.C. Electronic Packaging, Interconnection and Reliability Consulting 7 Jasmine Run Ormond Beach, FL 32174 USA Phone: 904-437-8747, Fax: 904-437-8737 E-mail: [log in to unmask], Website: www.engelmaier.com ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################