TS ISO 2859-2

TS ISO 2859-2 addresses sampling plans indexed by limiting quality (LQ) for attribute inspection when lots are isolated and the switching rules of ISO 2859-1 are not applied. In practical terms, it gives a structured way to assess a lot on the basis of defectives or nonconformities rather than measured variables, with particular relevance where lots are not part of a continuous production sequence.

How LQ indexing is used in practice

LQ is the limiting quality reference used to organize the preferred series of plans in this part of ISO 2859. Instead of treating an ad hoc lot as a special case each time, the standard provides a standardized procedure that can be matched to a chosen limiting quality level. The stated consumer’s risk is usually below 10 %, and always below 13 %, which helps define the intended conservatism of the plans.

Why isolated-lot inspection needs its own approach

From a general technical standpoint, attribute inspection is used when items are classified as conforming or nonconforming, accepted or rejected, rather than being evaluated by a continuous measurement scale. That distinction matters for isolated lots because the usual switching logic for ongoing streams of production may not fit. This part of ISO 2859 provides a compatible framework for those situations, extending the ISO 2859 family into a standardized procedure for ad-hoc lot inspection.

• Sampling plans and procedures for inspection by attributes
• Use when ISO 2859-1 switching rules are not applied
• Suitable for isolated or single lots
• Indexed by preferred series of limiting quality values (LQ)
• Consumer’s risk usually below 10 %, always below 13 %