API 570: Pipeline Inspection Code
Standard for in-service inspection, maintenance, repair, and rerating of oil and gas pipelines. API 570 mandates periodic external ultrasonic thickness inspections, pigging (internal inspection), radiography of repairs, and visual inspections. Compliance with API 570 is legally required for pipeline safety. API 570 inspector certification is recognized globally.
The American Petroleum Institute (API) publishes the in-service inspection standards that govern downstream and midstream petroleum equipment.
OSHA Process Safety Management (29 CFR 1910.119) and EPA Risk Management Program rules cite API inspection standards as recognised and generally accepted good engineering practice (RAGAGEP), so non-compliance is enforced indirectly through PSM audits.
API 570 is invoked when the scope of work matches its title — pipeline inspection code — and when the contract or regulatory regime cites it as the controlling document. On petroleum and petrochemical equipment, API 570 usually feeds into a written mechanical-integrity program: inspection intervals, examination methods, and acceptance criteria are all traced back to a clause number in the document.
Methods covered
Industries
- Oil & Gas
- Pipeline
- Petrochemical
- Personnel qualification: examinations under API 570 must be performed by inspectors qualified and certified to a recognised scheme (typically ASNT SNT-TC-1A, CP-189, or ISO 9712 depending on jurisdiction), with documented training hours, vision tests, and a controlling written practice.
- Written procedure: every examination requires a written, controlled procedure that names the method, equipment, calibration steps, scanning pattern, and acceptance criteria — and is qualified before first use.
- Equipment verification: ultrasonic instruments must be verified against a calibration block (V1, V2, IIW, or job-specific reference) at intervals defined by the procedure — typically before use, every four hours of scanning, on operator change, and at end of shift.
- Image-quality verification: every radiograph or digital exposure carries a penetrameter / IQI of the type and thickness specified by the standard; the IQI must be visible and at the required sensitivity for the radiograph to be acceptable.
- Radiation safety: source handling, exclusion zones, dosimetry, and source recordkeeping must follow the licensing authority's rules in addition to the inspection standard itself.
- Magnetic-particle technique: magnetisation method (yoke, prods, central conductor, multidirectional), field strength verification (pie gauge, Hall-effect meter, or QQI), and demagnetisation are all specified in the written procedure.
- Acceptance criteria: indications are evaluated against the standard's tabulated limits (length, depth, alignment, frequency); any indication exceeding the criteria is recorded, dispositioned, and either repaired or evaluated for fitness-for-service.
- Documentation: examination reports must include enough information for a third party to reproduce the inspection — equipment serial numbers, calibration records, inspector ID, sketches of indications, and the controlling procedure revision.
- Inspection intervals: API 570 sets maximum intervals between inspections based on remaining-life calculations or fixed default intervals; an authorised inspector must approve any extension based on documented risk-based-inspection analysis.
- Latest Edition
- 5th edition (2021 with addenda)
- First Published
- 1993
- Scope
- In-service inspection, repair, alteration, and rerating of metallic and FRP piping systems.
- Acceptance Criteria
- Minimum thickness per ASME B31.3 calculation; circuit-based intervals per service-class table (Class 1/2/3/4).
- Calibration / Qualification
- API 570 Authorised Piping Inspector (separate ICP certification); supporting NDE per Section V.
Key Clauses Inspectors Cite
- Sec. 5 — Inspection and Testing Practices
- Sec. 6 — Frequency and Extent of Inspection
- Sec. 7 — Inspection Data Evaluation, Analysis, Recording
- Sec. 8 — Repairs, Alterations, Rerating
Companion / Parent Standards
API 574 (piping inspection practices) · API 578 (PMI) · API 579-1/ASME FFS-1 · API 580/581 (RBI) · ASME B31.3
Sample Contract Language
“Piping inspection per API 570 5th ed.; thickness monitoring per Sec. 5; circuit classification documented per Sec. 6.”
API revises its inspection codes on roughly a five-to-seven-year cycle, with addenda issued in between. Recent updates to API 570 have continued the move toward risk-based-inspection (RBI) as an accepted basis for setting inspection intervals, expanded coverage of damage mechanisms, and updated cross-references to the latest editions of API 579 (fitness-for-service) and API 580/581 (RBI). The version cited in a written mechanical-integrity program should be tracked in the document control system so that any update flows through to the inspection plan.
A typical refinery turnaround applies API 570 to the inspection scope for high-temperature piping and pressure vessels: corrosion-monitoring locations are read with UT thickness gauges, girth welds on repaired sections are radiographed or PAUT-scanned, and any indication outside the standard's acceptance table is dispositioned through API 579 fitness-for-service before the unit restarts.
What does API 570 cover?
API 570 (Pipeline Inspection Code) is published by API. Standard for in-service inspection, maintenance, repair, and rerating of oil and gas pipelines.
What is the history of API 570 and the most common misuse to avoid?
API 570 (in-service piping) was published in 1993 as the piping counterpart to API 510, after the Mitchell, Mississippi natural-gas-liquids pipeline failure focused industry attention on piping mechanical integrity. The current edition (5th, 2022) covers metallic piping in service in petroleum refineries and chemical plants. API 570 inspectors routinely under-scope dead-leg piping. The code has explicit requirements for dead-leg identification and TML placement that get missed when the inspection is built off the as-built P&ID rather than a walk-down — by which point the corrosion has already happened.
Which sister standards is API 570 typically used with?
Pairs with API 574 (inspection practices for piping), API 571 (damage mechanisms), and API 579 (fitness-for-service) for piping disposition.
Is API 570 mandatory or voluntary?
API 570 is a consensus standard. It becomes mandatory when invoked by a contract, by another code that cites it (for example ASME Section V calling out an ASTM practice), or by a regulator that has adopted it into law in a specific jurisdiction.
Who is qualified to perform inspections under API 570?
Inspections under API 570 must be performed by personnel qualified and certified to a recognised NDT certification scheme — most commonly ASNT SNT-TC-1A or CP-189 in the United States, ISO 9712 in much of the rest of the world, and NAS 410 for aerospace work. The written practice that controls qualification must be in place before any examination is started.
How does API 570 interact with ASME Section V?
API 570 typically references ASME Section V for the underlying examination methods and acceptance criteria, then layers on the API-specific inspection intervals, damage-mechanism coverage, and Authorised Inspector requirements that apply to in-service equipment.
Standard Code
API 570
Organization
API
Methods Covered
4 method(s)
Industries
3 sector(s)
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