Different ASME Design Codes for Piping System

Purpose of ASME Design Codes:

Before the start of design work on any new project we need to know what the design code is,since the piping system would be designed according to the guidelines & the requirement of the applicable code.


Generally the information on the applicable code would be given by the owner or the Process Licensor in the Basic Engineering Package(BEP) or Piping design basis. The design contractors has to get this information before they start their work & if missing they need get it confirmed it with the owner.The design contractor shall ensure they are following the latest edition of the code.

As per ASME code:

“It is the owner’s responsibility to select the Code Section that most nearly applies to a proposedpiping installation. Factors to be considered by the owner include limitations of the Code Section;jurisdictional requirements; and the applicability of other codes and standards. All applicablerequirements of the selected Code Section shall be met. For some installations, more than oneCode Section may apply to different parts of the installation. The owner is also responsible forimposing requirements supplementary to those of the Code if necessary to assure safe pipingfor the proposed installation.

The design contractors shall also ensure that we are using the latest & the correct edition of the code.”

List of ASME codes:

Below are the ASME codes used for the design of the piping system in the oil & gas industry:

ASME B31.1

 – Power Piping: piping typically found in electric power generating stations, in industrialand institutional plants, geothermal heating systems, and central and districtheating and cooling systems

ASME B31.3

 – Process Piping: piping typically found in petroleum refineries; chemical,pharmaceutical,textile, paper, semiconductor, and cryogenic plants; and related processing plantsand terminals

ASME B31.4

 – Pipeline Transportation Systems for Liquids and Slurries: piping transporting productsthat are predominately liquid between plants and terminals and within terminals,pumping, regulating, and metering stations

ASME B31.5

 – Refrigeration Piping: piping for refrigerants and secondary coolants

ASME B31.8

 – Gas Transmission and Distribution Piping Systems: piping transporting products thatare predominately gas between sources and terminals, includingcompressor, regulating,and metering stations; gas gathering pipelines

ASME B31.9

 – Building Services Piping: piping typically found in industrial, institutional, commercial,and public buildings, and in multi-unit residences, which does not require therange of sizes, pressures, and temperatures covered in B31.1

AMSE B31.11

 – Slurry Transportation Piping Systems: piping transporting aqueous slurries betweenfacilities, plants, and terminals, and within terminals and pumping and regulatingstations.

ASME B31.12

 – Hydrogen Piping and Pipelines: piping in gaseous and liquid hydrogen service andpipelines in gaseous hydrogen service.

Additional codes:

As per ASME code:

Certain piping within a facility may be subject to other codes and standards, including but not limited to

– ANSI Z223.1 National Fuel Gas Code: piping for fuel gas from the point of delivery to theconnection of each fuel utilization device

– NFPA Fire Protection Standards: fire protection systems using water, carbon dioxide,halon,foam, dry chemicals, and wet chemicals

– NFPA 99 Health Care Facilities: medical and laboratory gas systems

– Building and plumbing codes, as applicable, for potable hot and cold water, and for sewerand drain systems


  1. what is the differance between asme b31.3 and asme b31.4

    • Hi Arun,

      ASME b31.3 is the code for process piping which is generally used for petrochemical and oil and gas plants while ASME b31.4 is the code for liquid transportation which is generally used for transportation of hydrocarbons and other fluids from one location to another.


  2. Dear Sir,

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