What is ISO 2859‑2 about?
ISO 2859‑2 is the second part of the ISO 2859 series of documents on sampling procedures for inspection by attributes. ISO 2859‑2 is an international standard on sampling procedures for inspection by attributes to ensure consistent product quality.
ISO 2859‑2 specifies an acceptance sampling system for inspection by attributes indexed by limiting quality (LQ). The sampling system is used for lots in isolation (isolated sequences of lots, an isolated lot, a unique lot, or a short series of lots), where switching rules, such as those of ISO 2859-1, are not applicable.
The sampling plans in ISO 2859‑2 are indexed by a series of specified values of limiting quality (LQ), where the consumer’s risk (the probability of acceptance at the LQ) is usually below 0,10 (10%), except in some instances.
Who is ISO 2859‑2 for?
ISO 2859‑2 on sampling procedures for inspection by attributes are useful for:
- Internal and external auditors
- Suppliers of steel products
- The retailers of steel products
- Manufacturing units
Why should you use ISO 2859‑2?
Sampling inspection plans are designed to protect the interest of the producer and consumer. This is accomplished by specifying quality levels and the associated risks of acceptance and rejection.
ISO 2859‑2 provides you with a technique to determine the acceptance or rejection of a lot or population based on several defective parts found in a random sample drawn from the lot. If the number of defective items does not exceed a predefined level, the lot is accepted, otherwise, it is rejected.
The procedures provided by ISO 2859‑2 helps you to verify that product specifications are being met and to determine the quality level of products.
What is changed since the last update?
BS ISO 2859‑2:2020 supersedes BS 6001‑2:1993. BS ISO 2859‑2:2020 includes some technical changes concerning BS 6001‑2:1993. These include:
- Inclusion of a sampling plan for the number of nonconformities per item in the lot
- Extension of the range of preferred LQ values from the original range "0,5 0,8 1,25 2 3,15 5 8 12,5 20 31,5 to the new one "0,05 0,008 0,125 0,2 0,315 0,5 0,8 1,25 2 3,15 5 8 12,5 20 31,5 50 80 125 200 315 500 800 1 250 2 000 3 150"
- Tables of shortest length confidence intervals for lot proportion nonconforming under confidence levels 0,95 and 0.99
- New technical annexes: Annex A on "Statistical properties of single sampling plans", Annex B on "Calculation of the statistical indices" and Annex C on "Information on the technical background of confidence intervals"