Ralph, The IPC has a comparison between IPC-4101 and MIL-S-13949, which was put together by Doug Sober, IPC Base Materials Committee chair. Please contact me directly for an electronic file of the comparison. You might also be interested in a workshop the IPC is offering in September on this issue: Base Materials and Laminates: Setting the Standard and Charting the Future. The workshop is in two parts, with the first part educating people on how to make the transition from MIL-S-13949 and its associated QPLs to IPC-4101. The following are only a few of the many topics that will be covered. The history of IPC-4101 development Laminate and prepreg qualification Quality conformance testing IPC-1730 Laminator Qualification Profile The flammability test method The second half of the workshop will be on alternatives to FR-4, which will discuss new base materials being developed to meet the demanding criteria of highly populated boards and high density interconnect systems. The following are the dates and cities where the workshops will be taking place. Sept. 10 - Los Angeles Sept. 11 - San Jose Sept. 14 - Boston Sept. 15 - Dallas Sept. 16 - Minneapolis For more information on these workshops, you can contact Maryellen Hildebrand at (847) 509-9700, ext. 382, or e-mail [log in to unmask] I hope that the above information answers your questions. Best regards, Chris Jorgensen Project Manager IPC 2215 Sanders Rd. Northbrook, IL 60062-6135 -p- 847-509-9700 x.328 -f- 847-509-9798 [log in to unmask] http://www.ipc.org IPC/SMTA Electronics Assembly Expo October 24 - 29, 1998 Rhode Island Convention Center Providence, RI www.ipc.org/html/assemexpo.htm >>> "Vaughan, Ralph H" <[log in to unmask]> 07/31/98 08:06AM >>> Hi Guys, With the rapidly approaching death of Mil-S-13949 (Nov), it is presumed that IPC-4101 will become the standard for PWB laminate materials. If any laminate suppliers or board fab folks have done a comparitive breakdown of these two documents and slash sheets, it would sure save a lot of peoples a lot of time. If not, maybe this could be an output of Steve's well documented Dallas trip in Sept. Thanx Ralph Vaughan Boeing-Atlanta 770 497-5222 ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################