Jim, One of our customer use 10 microgram/in2 as a pass or fail criteria for bare boards, using the modified rose test. [log in to unmask] -----Original Message----- From: DesignerCouncil [mailto:[log in to unmask]]On Behalf Of Walton, Jim Sent: Thursday, December 02, 1999 12:37 PM To: [log in to unmask] Subject: [DC] IPC Ionic test Hey everyone, Has anyone come to a conclusion when using IPC-tm-650 number 2.3.39? Item 6.8 clearly avoids any usable answer. I am looking for max. acceptable levels of contaminants for bare boards (incoming from the fab house) and assembled boards (before they are shipped from our dock). How about a listing of severity of certain contaminants as they pertain to dendrite growth on pcbs? I have test results, but I'm not a chemist so I am having a hard time coming up with definitive answers to what is "bad" and what can pass. I know there must be "real world" experienced people out there that can help. TIA Jim Walton