scope:

This Addendum provides additional requirements specified for rail transit applications over those published in IPC-A-610G. It prescribes the practices and requirements for the manufacture of electronic assemblies in rail transit industry, and applies to Class 3 to ensure industry-specific high reliability and environmental adaptability.

This Addendum is used in conjunction with IPC-A-610G.

For the purpose of this Addendum, if a conflict occurs between the English version and other versions of this document, the English version will take precedence.

This Addendum particularly supplements or replaces Class 3 requirements in IPC-A-610G. Clauses not involved and requirements not mentioned, i.e., Class 1, 2 requirements, are subject to the corresponding provisions of IPC-A-610G.

The clauses modified by this Addendum do not include subordinate clauses unless specifically stated, i.e., changes made to 1.7 do not affect 1.7.1 unless 1.7.1 is also addressed in this Addendum.

When a paragraph refers to an entire section, e.g., the first paragraph in Section 10 of this Addendum, it's the responsibility of the Addendum users to determine which clauses from that section, e.g., 10.2.2, are used from IPC-A-610G and which clauses are covered by this Addendum.

Tables/Figures, including newly added as well as original or modified from IPC-A-610G, in a section in this Addendum are numbered from "1R", e.g., Table 7-1R, and Figure 7-1R, 7-2R in section 7.

This Addendum does not specify frequency of in-process or frequency of end-product inspection. No limit is placed on the number of Process Indicators or the number of allowable repair/rework of Defects. Such information should be developed with a SPC plan (see IPC-9191). Whenever special process is involved, e.g., soldering, crimp, ISO/TS 22163:2017 and relevant documents shall apply.