Dear Technet, We'd like some clarification (interpretation) of the requirements noted in: J-Std-001B pg.27 paragraph 10.1.2.2 - Coating Coverage... IPC-A-610B pg.74 paragraph 7.1.2 - Coating Coverage... d. Be free of voids, BUBBLES, or foreign material which EXPOSE component conductors, printed wiring conductors (including ground planes) or other conductors, and/or violate design electrical spacing. Does the word "expose" in (d.) above mean; - No voids, bubbles, or foreign material "over" the runs (that the bubbles may open over time due to temperature and pressure variations and "expose" the conductors)? - That voids, bubbles, or foreign materials indicate an absence of the minimum required thickness of conformal coating? - Or the literal meaning of "expose" - to leave bare, endanger? We have received some PWAs with conformal coating that have bubbles between and over conductor runs and around and on components. The bubbles over the runs are not broken open (not literally exposing the conductor). The coating when viewed with the unaided eye appears hazy due to the multitude of tiny bubbles throughout the coating. There are larger bubbles and small bubbles between runs that when added together would violate the minimum spacing requirements. As I mentioned before, the bubbles are of various size and numerous enough to make the coating appear porous (spongy looking) mostly tiny bubbles throughout. We are required by contract to meet J-Std-001B class 3. We would appreciate your help in sorting through this confusion. Thanks, Dominick Scarano Lockheed Martin Mfg. Training ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################