Using acceptance sampling without inventing an AQL rule

Acceptance sampling checks a defined lot by inspecting selected units. It is not a guarantee that every item is free of defects. The ISO 2859 series concerns attribute sampling, but a buyer still has to select the applicable plan and parameters for the product and contract.

Decide before drawing samples

Define the lot, how units will be selected, defect classes, inspection level, and acceptance and rejection numbers using the applicable standard or a qualified quality professional. Do not borrow a sample size or “AQL” number from another product without context. Make sure the supplier understands which defects are critical and how disputed classifications will be resolved.

Keep the decision trace

Record lot ID, population, plan reference, sampled unit IDs, results, and disposition. A failed lot needs a documented next step such as sorting, rework, or rejection and a clear retest basis. A passed lot may still need other functional or regulatory evidence.

Worked lot record

For a hypothetical lot of 2,400 units, have the quality owner select an applicable attribute-sampling plan and record its exact reference, defect classes, sample size, and accept/reject numbers. The sample review tool can hold the lot ID and observations, but it does not calculate ISO 2859 tables. Mark unchecked features as “Not checked”. Common error: copying “AQL 2.5” from an unrelated product and treating it as a complete plan. Preserve each sampled unit result and the disposition of the lot.

Source context: ISO — Introduction to the ISO 2859 series supports this limited point: The ISO 2859 series concerns acceptance sampling by attributes. The buyer procedure above is Suppliers Help editorial guidance. Source checked 2026-09-27.