TS ISO 7870-3

TS ISO 7870-3 focuses on acceptance control charts and provides general guidance on how they are used, how sample sizes are determined, and how action limits and decision criteria are established. In the context of statistical process control, this charting approach is a more specialised tool than ordinary monitoring charts because it is intended to support acceptance-oriented decisions.

The role of an acceptance control chart

In general technical terms, control charts track process variation over time so that common-cause fluctuation can be distinguished from unusual shifts. Acceptance control charts are used when the process is already sufficiently stable and capable, and the objective is to make acceptance decisions about output or lots in a disciplined way. For that reason, they differ from routine surveillance charts in both sampling design and decision logic.

Conditions identified by this part

• Within-subgroup variation must be in control and estimated efficiently.
• A high level of process capability must have been achieved.
• The standard gives general procedures for using acceptance control charts and for setting sample sizes, action limits and decision criteria.
• Its terminology base aligns with statistical vocabulary standards such as TS ISO 3534-1 and TS ISO 3534-2.

The value of this standard lies in showing how acceptance decisions can be based on predefined limits and sampling rules rather than on ad hoc judgment. This makes the charting approach more systematic in production and quality assurance settings. At the same time, the document provides a general framework for acceptance control charts rather than a product-specific performance guarantee.