ASME B31.3
The global benchmark standard governing materials, design, fabrication, assembly, erection, examination, and testing of process plant piping systems.
- •Extent of examination based on fluid service (100% RT/UT for Severe Cyclic & Category M)
- •Visual examination (VT) of 100% of fabrication and minimum 5% random spot NDT for Normal Fluid Service
- •Ultrasonic testing (UT/PAUT) per ASME Sec V Art 4 with B31.3 Table 341.3.2 acceptance limits
ASME B31.1
Mandatory rules for high-pressure power piping systems found in electric power generating stations, industrial steam plants, boiler external piping (BEP), and central heating.
- •Boiler External Piping (BEP) compliance with ASME Section I Stamping rules
- •Mandatory 100% RT or UT/PAUT for piping over NPS 2 (DN 50) and > 750°F (400°C) or > 1025 psi (7 MPa)
- •Magnetic particle (MT) or penetrant (PT) surface examination of high-stress attachment welds
API 570
The authoritative standard for establishing in-service inspection intervals, corrosion rate calculations, fitness-for-service (FFS), and remaining life for operational refinery piping.
- •Classification of piping systems (Class 1 high risk / Class 2 / Class 3 / Class 4 unclassified)
- •Ultrasonic thickness (UT) measurements at CMLs and baseline tracking
- •Pulsed Eddy Current (PEC) or Radiographic CUI profile inspection through insulation
API Standard 1104
The definitive American pipeline standard governing arc and gas welding of butt, fillet, and socket welds in carbon steel transmission pipelines.
- •Welder qualification coupons tested via nick-break, tensile, and root/face bend tests
- •Radiographic testing (RT) or Automated Ultrasonic Testing (AUT / PAUT) on 100% of cross-country welds
- •Mechanized welding procedure qualification (GMAW / FCAW bug-and-band systems)
ASME B31.4
Governs design, materials, construction, assembly, inspection, testing, and safety aspects of liquid hydrocarbon transport pipelines.
- •Minimum NDT coverage: 10% random NDT for liquid lines, 100% for river/railroad crossings
- •In-line inspection (ILI / Smart Pigging) launcher/receiver trap design
- •Hydrostatic strength testing at minimum 1.25x Maximum Operating Pressure (MOP) for 4–8 hours
ASME B31.8
Comprehensive code for gas transmission pipelines, compressor stations, gas metering facilities, and urban gas distribution mains.
- •Location Class 1 to Class 4 dictates mandatory NDT percentage (up to 100% RT/AUT in Class 3 & 4)
- •Direct Assessment methodologies (ECDA for external corrosion, ICDA for internal corrosion)
- •Compressor station piping 100% volumetric examination (RT or UT)
API RP 574
Recommended practice detailing specific inspection methods, failure modes, tools, and practices for pipes, valves, flanges, tubing, and fittings.
- •Visual inspection of flange face gasket surfaces (serrated finish damage)
- •Radiographic profile inspection (profile RT) for internal wall loss and scale buildup
- •Ultrasonic thickness scanning of pipe elbows and high-velocity turbulence zones
EN 13480 (Parts 1–8)
Harmonized European standard specifying requirements for industrial piping systems made of metallic materials to satisfy the EU Pressure Equipment Directive (PED).
- •Extent of NDT determined by Piping Category and Joint Efficiency (0.7 to 1.0)
- •Mandatory NDT testing matrix per EN 13480-5 (VT, PT/MT, UT/RT)
- •Pressure testing: Hydrostatic test at 1.43x design pressure or pneumatic test
CSA Z662
The Canadian standard for the design, construction, operation, maintenance, and NDT inspection of oil and gas pipeline systems and offshore pipelines.
- •100% NDT examination (RT or AUT) for high-pressure oil and gas pipelines
- •Automated Ultrasonic Testing (AUT) qualification with custom zoned calibration blocks
- •Engineering Critical Assessment (ECA) for defect acceptance beyond workmanship standards