Greetings to All John Perry is going to try and get the photo to you all since the forum stripped it off the email. I am going to suggest that while we are thinking of the best way to address the words that will go into the various specifications - consider using a similar format as we use for hole wall plating voids. In that para we have words that further limit the acceptability of a plating void - such as "when present at the interface of an inner layer and prepreg". It could be that we could use words to draw the line, but include words that say "dielectric spacing must be maintained between ground or power plane clearances and between layers". Susan