GB/T 2828 consists of the following parts, under the general title Sampling procedures for inspection by attributes:
Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection (ISO 2859-1:1999, IDT)
Part 2: Sampling plans indexed by limiting quality (LQ) for isolated lot inspection (ISO 2859-2:1985, NEQ)
Part 3: Skip-lot sampling procedures (ISO 2859-3:2005, IDT)
Part 4: Procedures for assessment of declared quality levels (ISO 2859-4:2002, MOD)
Part 5: System of sequential sampling plans indexed by acceptance quality limit (AQL) for lot-by-lot inspection (ISO 2859-5:2005, IDT)
Part 10: Introduction to the GB/T 2828 series of standards for sampling for inspection by attributes (ISO 2859-10:2006, MOD)
Part 11: Procedures for assessment of declared quality levels for small population
This is Part 1 of GB/T 2828.
This part of GB/T 2828 specifies an acceptance sampling system for inspection by attributes. It is indexed in terms of the acceptance quality limit (AQL).
Its purpose is to induce a supplier through the economic and psychological pressure of lot non-acceptance to maintain a process average at least as good as the specified acceptance quality limit, while at the same time providing an upper limit for the risk to the consumer of accepting the occasional poor lot. Sampling schemes designated in this part of GB/T 2828 are applicable, but not limited, to inspection of
—— end items,
—— components and raw materials,
—— materials in process,
—— supplies in storage,
—— maintenance operations,
—— data or records, and
—— administrative procedures.
The sampling schemes in this part of GB/T 2828 are intended primarily to be used for a continuing series of lots, that is, a series long enough to allow the switching rules (see 9.3) to be applied. These rules provide:
a) a protection to the consumer (by means of a switch to tightened inspection or discontinuation of sampling inspection) should a deterioration in quality be detected;
b) an incentive (at the discretion of the responsible authority) to reduce inspection costs (by means of a switch to reduced inspection) should consistently good quality be achieved.
Sampling plans in this part of GB/T 2828 may also be used for the inspection of lots in isolation but, in this case, the user is strongly advised to consult the operating characteristic curves (see 12.6) for sampling plans to find a plan that will yield the desired protection. In that case, the user is also referred to the sampling plans indexed by limiting quality (LQ) given in GB/T 2828.2-2008.