Acceptance quality limit, or AQL, is a parameter used with an acceptance-sampling plan to determine sample size and acceptance or rejection numbers. It is not a permitted percentage of defective goods.
How the control works
Specify the sampling standard, inspection level, lot size and separate AQL values for relevant defect classes. The plan should also state switching or reinspection rules.
| Area | What the record should show |
|---|---|
| Control | Specify the sampling standard, inspection level, lot size and separate AQL values for relevant defect classes. The plan should also state switching or reinspection rules. |
| Evidence | Keep the lot definition, sampling table, random selection method, defect counts and accept or reject decision. |
| Tradeoff | AQL sampling can accept a lot containing defects because it tests a sample. Critical characteristics may need tighter controls or full inspection. |
Evidence buyers should retain
Keep the lot definition, sampling table, random selection method, defect counts and accept or reject decision.
Where the term is misused
AQL sampling can accept a lot containing defects because it tests a sample. Critical characteristics may need tighter controls or full inspection.
Related definitions: quality inspection, defect classification, pre shipment inspection.
