At this time 55110 and 50884 both require cleanliness testing on inner layers only - so solder mask is not a concern. If cleanliness is an issue for someone who is buying boards then they must establish levels of cleanliness and what methods will be used to determine that level. As most discover it is very important that both parties use the same method or all bets are off. Susan Mansilla Robisan Laboratory *************************************************************************** * 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. * ***************************************************************************