Safety, environmental and economic pressures are motivating process industry (e.g. refineries & petrochemical plants) operators to consistently improve equipment reliability performance, optimize expenses and more accurately target resources where they will provide the greatest benefit. These improvements yield improved return on net assets (e.g. pressure vessels, piping and tanks). Companies that can better assure that decisions about repairs or replacement of equipment are more accurately arrived at are heading in the right direction.
In order to equip operators with tools for better decision making, the American Petroleum Institute, within the last few years, has introduced Recommended Practice (RP) 579 Fitness for Service (FFS), which had been in development for several preceding years. The latest versions of the widely used inspection codes; API 510 (pressure vessels), API 570 (piping) and API 653 (above ground storage tanks) now reference this RP as a tool for determining the fitness for service of these types of equipment when corrosion, cracking, or other forms of deterioration are found and in the case of re-rating equipment.