aql sampling definition
We use the internationally recognized Acceptable Quality Limit (AQL) standard for all product inspections. Clients can set their Acceptable Quality Tolerance level for each inspection and AI will provide results as within or beyond AQL. Acceptable Quality Limit (AQL) AsiaInspection Inspectors exclusively use ISO 2859 tables to measure AQL. These tables are a United States standard with equivalents in all national and international standardization organizations (ANSI/ASQC Z1.4, NF06-022, BS 6001, DIN 40080). ‘AQL’ stands for ‘Acceptance Quality Limit’, and is defined as the “quality level that is the worst tolerable” in ISO 2859-1. It decides on the maximum number of defective units, beyond which a batch is rejected. Importers usually set different AQLs for critical, major, and minor defects. In the table below, you can see how many samples would be drawn under each of the 7 inspection levels. As you can see, the numbers of samples to check vary from 5pcs to 315pcs. But a trained inspector might be able to do it in one day, whatever the inspection level you choose. AQL tables for product inspections. These statistical tables are fundamental tools for preparing a sampling plan for a random product inspection. They give you the number of samples to inspect, and the maximum numbers of defects that is allowed. The first table gives you the code letter for sampling. In this example, if the batch to check contains 5,000 pcs, and if you choose level II (which is chosen by default for most inspections), the letter is L. Hi Anjoran, our company uses Special inspection level S-2 for sampling check. When the sample size is 500, according to table is letter code C which is 5 pieces. However under the single sampling plan for NORMAL inspection, AQL=1.5%, the sample size becomes 8 pieces. The need for sampling, rather than 100% checking. When controlling the quality of a batch of products, it is not practical to inspect 100% of them (unless the quantity is very small). Inspecting a large number of products takes a long time: it is expensive, and inspectors are less effective as they get tired. The reason is that the ISO 2859-1 definition of AQL is simply incorrect. The actual definition of AQL is the percentage of defective parts that is routinely accepted by your sampling plan. Thus, a particular sampling plan for an AQL of 1%, might actually only reject a lot if there are 2% or more defectives. These special levels can be applied in cases where only very few samples can be checked. “Four additional special levels, S-1, S-2, S-3 and S-4 […] may be used where relatively small sample sizes are necessary and larger sampling risks can be tolerated” (ISO 2859 standard). The Acceptable Quality Limit, commonly referred to as AQL, is a method widely used to measure a production order sample to find whether or not the entire product order has met the client's specifications. The customer then has the data to make an informed decision to accept or reject the lot.
It is a method widely used to measure a production order sample to find whether or not the entire product order has met the client's specifications.