Scope, Definitions, and Organization of API 570
What API 570 governs
API 570 covers the inspection, rating, repair, alteration, and rerating of metallic piping systems that are in service in refineries, petrochemical and chemical plants, and similar process facilities. It follows a piping system for its whole in-service life, including idle periods before retirement. Learn the exclusions as well as the inclusions: pipeline transportation piping (covered by ASME B31.4/B31.8 and API 1160), boiler and furnace tubes, instrument tubing, and non-metallic piping fall outside the document.
Roles and definitions
Three roles drive most questions. The owner/user owns the program: it assigns responsibilities, approves inspection intervals, and approves repairs, alterations, and rerating. The authorized inspector is API 570 certified, qualified in the NDE methods used, and works in an inspection function independent of the operating and maintenance organizations. The repair organization must be approved by the owner/user and must use qualified welders and procedures.
Definitions must be applied, not recited: a repair restores the system to safe operation at existing design conditions; an alteration changes something with design implications (material, rating, or a change beyond the original design scope); rerating changes the design pressure or temperature and requires engineering review plus record updates. Deadlegs, injection points, soil-to-air interfaces, and auxiliary piping are named because they attract special inspection attention.
Worked example: replacing 20 ft of 6-in carbon steel line with pipe of the same specification is a repair; substituting 316L stainless steel for that carbon steel is an alteration because the material change has design implications.
Trap: questions that make the inspector the approver of intervals or of a rerating. The owner/user approves; the inspector recommends and documents.