In a message dated 96-11-16 00:47:32 EST, you write: >We had also noticed a high level of sodium and >chlorine when conducting our testing. How did you know it was Sodium and Chloride?? some ionic contamination measuring systems read out in units of Sodium Chloride, when in fact they do not really test if the conductivity was caused by Sodium Chloride. My questions are:>1. What would cause the ionic readings to intensify over time? The reason why I ask about the Sodium Chloride, and whether you are sure it really is Sodium Chloride, is that oxidation, and especially oxides of Tin and/or Lead will dissolve in some of the ionic contamination testers, and be read as "Sodium Chloride". What you may just be seeing is oxidation, which is expected to increase over time, and which would cause difficulty soldering. >2. What could be the possible origins of sodium and chlorine? Could they be >introduced >in any of PCB manufacturing processes? Rudy Sedlak RD Chemical Company *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************