Application of a Coating System to Interior Surfaces of New and Used Rail Tank Cars in Concentrated (90 to 98%) Sulfuric Acid Service

This standard is intended for use by tank car owners, coating systems suppliers, and coating system applicators for the auditing of the facilities, equipment, and personnel that satisfy the requirements for tank car coating systems in sulfuric acid service.

Industry consensus points to internal coating systems as a necessary protective measure for tank cars transporting concentrated sulfuric acid and to ensure product purity. Many shippers of sulfuric acid apply a protective coating system (usually a baked phenolic) to the interior surfaces of tank cars and specify a nominal steel corrosion allowance of 3.2 mm (0.13 in) in the event of coating failure. The life expectancies of these coating systems are highly dependent on the quality of the surface preparation, coating application, and quality control/quality assurance (QC/QA). For this reason, the proper application and inspection of interior coating systems is very important to the maintenance of tank cars hauling sulfuric acid.