API RP 574-2024 (2025) PDF

Full title and description

API RP 574: Inspection Practices for Piping System Components — Fifth Edition (2024) with Addendum 1 (2025). This Recommended Practice provides guidance, inspection methods, and industry practices for the inspection of piping, tubing, valves (other than control valves), and fittings used in petroleum refineries, petrochemical and chemical plants to support implementation of API 570 and improve piping inspector competency and consistency of inspections.

Abstract

API RP 574 supplements API 570 by describing common piping components and valve types, pipe-joining methods, inspection planning and prioritization, inspection intervals and techniques, pressure testing, techniques for determining minimum required thickness, recordkeeping, and evaluation of inspection results (including fitness‑for‑service and rerating considerations). The fifth edition (2024) includes updated guidance on selecting inspection activities and locations, stainless‑steel tubing in chloride service, assessment of inspection results, follow‑up actions, repairs and alterations. Addendum 1 (2025) amends and clarifies selected sections of the 2024 edition.

General information

• Status: Current (includes Addendum 1 published in 2025)
• Publication date: Fifth edition published February 2024; Addendum 1 published March 2025
• Publisher: American Petroleum Institute (API)
• ICS / categories: Petroleum and petrochemical engineering; piping inspection; mechanical integrity; process safety (industry category: piping systems / inspection)
• Edition / version: 5th edition (2024) with Addendum 1 (2025)
• Number of pages: Approximately 158 pages (published edition with addendum; page counts reported 150–170 depending on format)

Scope

Specifies inspection practices for piping, tubing, valves (other than control valves), and fittings in petroleum refineries and chemical plants. It covers inspection planning, inspection intervals and extents, techniques and procedures (including external and internal examinations and pressure testing), determination of minimum required thickness, recordkeeping, and evaluation of inspection findings. It does not cover specialty items such as instrumentation, furnace tubes, or the inspection of control valves unless explicitly referenced.

Key topics and requirements

• Identification and description of common piping components, valve types and fittings.
• Pipe‑joining methods and inspection considerations for welded, threaded, flanged and mechanical joints.
• Reasons for inspection and development of inspection plans (risk‑based prioritization).
• Recommended inspection intervals, extents and selection of inspection locations.
• Inspection procedures and techniques: visual inspection, non‑destructive examination methods, internal inspection, and pressure testing practices.
• Guidance on determining minimum required thickness and evaluating remaining life.
• Evaluation of inspection results, use of fitness‑for‑service approaches and rerating guidance.
• Repair, alteration and re‑inspection practices for damaged or degraded piping components.
• Recordkeeping, reports and documentation requirements for inspection activities.
• Updated guidance on stainless steel tubing in chloride service and other material‑specific considerations (fifth edition updates).

Typical use and users

Used by piping inspectors, mechanical integrity engineers, plant owners/operators, maintenance and reliability personnel, inspection contractors, and training organizations. It forms part of the body of knowledge for API piping inspector certification (API ICP) and is applied at refineries, petrochemical and chemical plants for developing inspection programs, preparing inspection plans, evaluating inspection results and supporting repair/alteration decisions.

Related standards

Closely associated with API 570 (Piping Inspection Code: In‑Service Inspection, Rating, Repair, and Alteration of Piping Systems). Other related API documents include API RP 578 (Material Verification Program), API RP 591 (Process Valve Qualification), API RP 572 (Pressure Vessel Inspection Practices) and API 510/512 series for pressure equipment; it is also used alongside industry piping design and integrity standards such as ASME B31.3 where applicable.

Keywords

piping inspection, API RP 574, inspection practices, piping components, valves, pipe‑joining methods, inspection planning, inspection intervals, non‑destructive examination, pressure testing, minimum required thickness, fitness‑for‑service, rerating, repairs, mechanical integrity, refineries, petrochemical.

FAQ

Q: What is this standard?

A: API RP 574 is a Recommended Practice from the American Petroleum Institute that provides practical guidance and industry practices for inspecting piping system components used in refineries and chemical plants.

Q: What does it cover?

A: It covers inspection planning, reasons for inspection, inspection intervals and extents, inspection techniques (visual and NDE), pressure testing, methods for determining minimum required thickness, recordkeeping, evaluation of results (including fitness‑for‑service and rerating), and guidance on repairs and alterations. It excludes specialized items such as instrumentation, furnace tubes and control‑valve inspection unless specifically referenced.

Q: Who typically uses it?

A: Piping inspectors, mechanical integrity and reliability engineers, plant maintenance staff, inspection contractors, safety and process‑safety teams, and trainers preparing personnel for API piping inspection certification programs.

Q: Is it current or superseded?

A: The fifth edition was published in February 2024 and was updated by Addendum 1 in March 2025. The combined 2024 edition plus Addendum 1 is the current, authoritative edition and supersedes earlier editions (for example the 2016 edition).

Q: Is it part of a series?

A: Yes. RP 574 is part of API’s piping inspection and mechanical integrity suite and is a companion to API 570. It complements other API recommended practices and standards that address inspection of pressure‑containing equipment, valve qualification, material verification and related topics.

Q: What are the key keywords?

A: Piping inspection, inspection practices, piping components, valves, NDE, pressure testing, minimum required thickness, fitness‑for‑service, rerating, repairs, mechanical integrity, API RP 574.