In chemical tanks this means resistance to deterioration from chemical exposure. These rugged, compact ultrasonic level sensors measure a wide variety of liquids from diesel fuel in rail locomotives to chemical tanks in the paper and food processing industries (not suited for high temperature CIP operations). Heavy duty electronics are epoxy potted into a polyvinylidene fluoride (PVDF) housing that physically isolates the transducer and electronics from the chemicals and can withstand exposure to both acids and bases. They are used both indoors and out, and in some of the harshest factory environments. They are also used in liquid level applications where chemical resistance is not required.