Viking offers a special protective coating when required by customers. This coating is a thin polyurethane film. Viking uses HumiSeal® 1A33 as a conformal coating material. Conformal coating is a protective chemical coating, or polymer film, 25µm - 75µm thick (50µm typical) that ‘conforms’ to the circuit board topology. Its purpose is to protect electronic circuits from harsh environments that may contain moisture or chemical contaminants. By being electrically insulating, it maintains long-term surface insulation resistance (SIR) levels and thus ensures the operational integrity of the assembly. It also provides a barrier to air-borne contaminants from the operating environment, such as salt-spray, thus preventing corrosion. Modules with conformal coating are generally required in ruggedized applications such as military, automotive, and aerospace, where coatings are used to protect against various combinations of moisture, aggressive chemical and vapors, salt sprays, large temperature variations, mechanical vibrations and even organic attack. The protective nature of conformal coatings means that they not only protect, but also serve to enhance product reliability and thereby reduce the potential cost and damaging effects of early field failures.