Introduction

This page provides an answer to a common question regarding the applicability of NACE MR0175/ISO 15156-3, A.12 to UNS C72900 and C96900 copper alloys. The inquiry asks if these alloys are covered by A.12, which states that copper alloys are suitable for use without restriction other than the note in the footnote.

Answer

The answer is straightforward: yes, UNS C72900 and UNS C96900 copper alloys are included in NACE MR0175/ISO 15156-3, A.12.

Background

This question pertains to NACE MR0175/ISO 15156-3 A.12, which is a standard that provides guidelines for the use of materials in sour service environments. The reference cited is ISO 15156 Maintenance Panel Inquiry #2003-21.

Conclusion

In conclusion, if you are using UNS C72900 or UNS C96900 copper alloys in sour service environments, you can be confident that they are covered by NACE MR0175/ISO 15156-3, A.12.