This document specifies the minimum technical requirements for surface preparation, materials, application, inspection and testing of internal coating and lining systems that are intended to be applied on internal surfaces of process vessels that are subject to marked pressure/temperature changes and/or potentially corrosive conditions or processes and aggressive chemicals, used in the oil and gas industry. This document covers both new construction and maintenance works of process vessels as well as the repair of defective and deteriorated coating and lining systems. This document also provides the minimum requirements for the coated and lined samples and the criteria for their approval.