DANSK DS/ISO 18414 PDF

This International Standard specifies an acceptance sampling system for lot-by-lot inspection by attributes. In contrast with ISO 2859-1, all sampling plans of the present system are of the accept-zero form, i.e. no lot is accepted if the sample from it contains one or more nonconforming items. This International Standard is only suitable when inspection is non-destructive. The objective is to provide accept-zero schemes and procedures for assuring, by means of the lowest practicable sample sizes, an upper limit to the long-term percentage of nonconforming items delivered to the market-place, i.e. a suitably defined average outgoing quality limit (AOQL). This objective is achieved by a progressive reduction of the sample size in response to good quality history, reversion to a relatively large sample size whenever a nonconforming item is found, and 100 % inspection of a) the first lot if it is non-accepted, or b) any non-accepted lot that immediately follows a non-accepted lot, with acceptance of any conforming items found in those lots. This International Standard is therefore particularly suitable for regulatory purposes, where control of the expected quality of items reaching the market-place is considered necessary. This International Standard can be used by suppliers/producers, buyers/consumers and regulatory agencies to provide control of the expected quality of the totality of accepted product of each type from each source. No restrictions are placed on the choice of AOQL, or on the sizes of successive lots in the series. This International Standard is designed for use under conditions where: i) items are of a similar type and value, all supplied by the same supplier; ii) the cost to the supplier for inspection increases with the number of items inspected; iii) it is possible to accurately determine whether or not the sampled items conform to specification.