According to Innodisk, DRAM modules with conformal coatings provide "greater reliability, superior service life, improved performance, and reduced total cost of ownership." Conformal coatings, in this case HumiSeal, are protective chemical layers applied to the surface of DRAM modules with thickness varying from .03mm to .13mm. With the exception of the gold conductor interface, the DRAM module surface is completely covered with the coating.
"These coatings protect against moisture, contaminants, dust and acid or alkaline materials, in line with IPC-A-610 standards for electronic components. They also protect against issues caused by electrical or thermal conduction, static electricity, and heat." The coatings conform to MIL-I-46058C standards, basically meaning they can withstand harsh environmental factors commonly encountered in the Defense & Aerospace sector.