TS ISO 2859-4

TS ISO 2859-4 belongs to the attribute sampling series and addresses how sampling plans and procedures can be used to assess whether the quality level of a lot, process, or similar entity conforms to a declared value. In practical terms, it focuses on checking a stated quality level rather than on a full acceptance/rejection scheme for every possible inspection case.

Assessing a declared quality level

The core idea is to use attribute-based observations to judge whether an entity actually matches the quality level that has been declared. In general technical terms, this kind of assessment is often expressed through measures such as defectives, nonconformities, or similar qualitative indicators. Sampling plans make it possible to base that judgment on a limited number of inspected items instead of examining the whole lot, which is especially relevant in high-volume production or routine process control.

What this part covers

According to its scope, this part of ISO 2859 establishes sampling plans and procedures for evaluating declared quality levels. It provides a procedural framework for assessing conformity to the stated value, but it is not a general quality management system standard and it does not, by itself, define every aspect of product conformity, process capability, or organizational quality assurance. Its value lies in situations where a quality level has been declared in advance and needs to be checked through sampling-based assessment.

This edition is withdrawn, but it remains a useful technical reference for understanding the logic of statistical sampling, the link between declared quality and decision-making, and the role of attribute inspection plans in quality evaluation.