Safety factors used by engineers in the design of corrosion resistant thermoset and thermoplastic process equipment can vary relative to the materials of construction, the type of equipment, and the anticipated service conditions. A number of standards from ASTM and ANSI/ASME are available to guide engineers in determining appropriate mechanical properties for a given material, choosing an appropriate factor of safety, and in testing prototype parts, as appropriate. Using the various plastics
industry specifications with knowledge of the service conditions, the design engineer can choose an appropriate factor of safety to ensure satisfactory service life. Keywords: fiberglass reinforced plastic, thermoplastic, composites, design, factor, corrosion