What are the Codes & Standards?

Codes are mandatory rules that govern the design, construction, and safety of systems in industries like oil and gas, while standards are detailed technical guidelines specifying materials, methods, and best practices. They become mandatory when referenced by a code or contract. Both aim to ensure safety, quality, and consistency, and are often used together to achieve compliance and reliability in industrial projects.

What are Codes

Codes are formalized sets of rules and requirements developed by recognized organizations to ensure the safety, reliability, and integrity of systems used in industrial sectors such as oil and gas and process plants. These codes cover the design, construction, installation, inspection, and maintenance of equipment and infrastructure. They are often mandatory, either enforced by government regulations or adopted through industry contracts and project specifications. For example, ASME B31.3 governs process piping, and API 570 provides requirements for piping inspection in the oil and gas industry. Compliance with codes is essential, as they serve as the legal and technical foundation for safe plant operation.

Key Points:

Purpose: It ensures safety, reliability, and regulatory compliance.
Legally Binding? Often mandatory—either enforced by government agencies or adopted by contracts and regulations

What are Standards

Standards, on the other hand, provide detailed guidelines, technical specifications, and recommended practices for materials, products, testing methods, and procedures. They are typically developed by standardization bodies such as ASTM, ISO, and NACE. While not always mandatory on their own, standards become enforceable when referenced by codes, contracts, or regulatory documents. For instance, ASTM standards specify the mechanical and chemical properties of steel pipes, and NACE MR0175 outlines material requirements for resistance to hydrogen sulfide corrosion. Standards help ensure consistency, quality, and interoperability across equipment and processes in the industry.

Key Points:

Purpose: To ensure consistency, interchangeability, and performance quality.
Legally Binding? Usually voluntary, unless referenced by a code, contract, or regulation.

Here’s a list of commonly used codes in the oil & gas and process industries, grouped by standard organizations: ASME, ASTM, and API. Each includes the code number/name and a title. Follow the links for getting on overview of these codes and standards and their usage.

ASME (The American Society of Mechanical Engineers)

ASME B16.34 – Valves Flanged, Threaded and Welding End – Design, materials, and pressure-temperature ratings for flanged and welded-end valves.
ASME B16.5 -Flanges and Flanged Fittings – Dimensions and pressure-temperature ratings.
ASME B16.9 – Buttwelding Fittings – Elbows, tees, reducers, etc.
ASME B16.10 – Valve Face-to-Face and End-to-End Dimensions.
ASME BPV Code Section VIII Division 1 – Rules for design and construction of pressure vessels
ASME B31.1 – Power Piping – Applies to piping in electric power generating stations.
ASME B31.3 – Process Piping – Design and construction of piping systems for chemical and petroleum plants
ASME Section IX – Welding and Brazing Qualifications – Requirements for welding procedures and personnel.
ASME Section V – Non-destructive Examination – Covers RT, UT, PT, MT methods.
ASME Section II – Materials Specifications – Defines acceptable materials for pressure applications.

ASTM (American Society for Testing and Materials)

ASTM A53 –  Welded and Seamless Steel Pipe for pressure and mechanical applications.
ASTM A105 – Carbon Steel Forgings for piping components like flanges and fittings.
ASTM A106 – Seamless Carbon Steel Pipe for High-Temperature Service.
ASTM A193 – Alloy and Stainless Steel Bolting Materials for high-temp service.
ASTM A234 – Steel Pipe Fittings – Wrought carbon and alloy steel fittings.
ASTM A182 – Forged or Rolled Alloy/Stainless Steel Pipe Flanges and Fittings.
ASTM A312 – Austenitic Stainless Steel Pipe – Seamless and welded.
ASTM A333 – Low-Temperature Steel Pipe – Seamless and welded.
ASTM A516 – Pressure Vessel Plates – Carbon steel for moderate/low-temp service.

API (American Petroleum Institute) 

API 570 – Piping Inspection Code – Inspection and repair of in-service piping
API 610 – Centrifugal Pumps for Petroleum, Petrochemical, and Natural Gas industries
API 620 – Design and Construction of Large, Welded, Low-Pressure Storage Tanks 
API 650 – Welded Steel Tanks for Oil Storage
API 600 – Standard for Steel Gate Valves—Flanged and Butt-welding Ends, Bolted Bonnets 
API 653 – Tank Inspection, Repair, Alteration, and Reconstruction
API 6D – Pipeline Valves – Gate, ball, plug, and check valves specifications
API 2000 -Venting Atmospheric and Low-Pressure Storage Tanks
API 579/ASME FFS-1 – Fitness-for-service assessment for tanks and pressure vessels.