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The most frequently referenced specifications are IPC-CC-830 and MIL-I-46058C. These standards, are the core of the conformal coating of printed circuit assemblies and have an interesting past and sometimes confusing present.

IPC-CC-830, Qualification and Performance of Electrical Insulating Compound for Printed Wiring Assemblies and MIL-I-46058C, Insulating Compound (For Coating Printed Circuit Assemblies) define the standardized testing required before a coating can be said to have met the requirements of IPC-CC-830 or MIL-I-46058C. They are not workmanship standards. IPC-CC-830 and MIL-I-46058C do not define the quality of application.

In the printed circuit community the most common workmanship citations are IPC-A610, Acceptability of Electronic Assemblies, and IPC J-STD-001, Requirements for Soldered Electrical and Electronic Assemblies, both of which offer modest but valuable conformal coating guidance

Historically, the issuing federal agency deactivated MIL-I-46058C in November of 1998. This deactivation meant the standard was ‘inactive for new design and is no longer used, except for replacement purposes’. That did not, however, mean MIL-I-46058C would disappear from the landscape and it certainly has not.

Seeking to fill the void left by the deactivation of MIL-I-46058C, IPC issued IPC-CC-830A in July 1999. The general thinking was that some of the testing methodologies in 46058C were obsolete and arcane and that a new, streamlined, methodology, as contained in IPC-CC-830, could get the same level of performance and security in a more efficient fashion. In fact, incorporated into IPC-CC-830 is a statement reconciling the two standards ’ 3.2.1…….Conformal coatings presently qualified to MIL-I-46058C shall also be recognized as meeting the requirements of IPC-CC-830……….’.

Unfortunately, because 46058C was inactive and unsupported, its’ writers were unable to retroactively reciprocate the favor and link 46058C to 830. The result is that coatings that meet the requirements of MIL-I-46058C by default are qualified to IPC-CC-830. The coatings that meet IPC-CC-830 ARE NOT automatically qualified to MIL-I-46058C.

In sum, while MIL-I-46058C was deactivated in 1998, it is still a common requirement. IPC-CC-830 and MIL-I-46058C achieve the same goal of ensuring a coating is suitable for use but they arrive at it in somewhat different ways. Advanced Coating Parylene meets the requirements of both IPC-CC-830 and MIL-I-46058C.