MR0175/ISO 15156 Standard

MR0175/ISO 15156 is a federally mandated standard in the United States and is globally recognized as ISO 15156. MR0175/ISO 15156 address requirements and recommendations for selection and qualification of materials for H2S service in oil and natural gas production. MR0175/ISO 15156 addresses all forms of cracking caused by H2S and applies to equipment using conventional elastic design criteria.

The standard addresses requirements and recommendations for the selection and qualification of carbon and low-alloy steels, corrosion-resistant alloys, and other alloys for service in equipment used in oil and natural gas production and natural gas treatment plants in H2S-containing environments.

NOTE: Due to the formation of the Association of Materials Performance & Protection (AMPP) we are in the process of back adopting the 2020 ISO 15156 version of the ANSI/NACE MR0175 standard.  We will advise when the new version is available for purchase.

It is also perhaps, one of the most complex and most misunderstood standards in corrosion . Compendiums of interpretations, areas of opinions, lists of corrections and updates are issued regularly. This creates dated and conflicting information in the marketplace, but NACE International offers instruction from the world’s leading industry experts.

Document Structure

Part 1, General principles for the selection of cracking-resistant materials

Part 2, Cracking-resistant carbon and low alloy steels, and the use of cast irons

Part 3, Cracking-resistant CRAs (corrosion-resistant alloys) and other alloysSulfide Stress Cracking (SSC), Stress Corrosion Cracking (SCC)

*MR0175/ISO 15156 is currently in English, French, Chinese, and Spanish.
**Not intended for refinery equipment (NACE Standard MR0103 should be used).


The purpose of ANSI/NACE MR0175/ISO 15156 is to:

The responsibility for safe application of alloys is defined as follows:

Manufacturers and suppliers provide materials that meet:

  • NACE MR0175/ISO 15156 minimum metallurgical requirements
  • chemistry, mechanical properties, hardness, and processing
  • USER - specified additional metallurgical requirements

Users are responsible for the materials selection and defining the environment

  • Oil company
  • Contractor (if delegated)
  • Service (if delegated)
  • NOT the manufacturer or supplier (materials and components).