Learning objectives
- Pick the right sample size
- Read AQL tables without confusion
Steps
- Confirm lot size
- Choose inspection level (usually II)
- Pick AQL (commonly 2.5)
- Sample randomly, not from top of cartons
- Apply accept / reject numbers
Factory example
A 5,000-pc lot where a rushed inspector sampled top cartons only, hid a defect cluster, and the buyer failed the shipment on re-inspection.
Common mistakes
- Cherry-picking cartons
- Confusing AQL 2.5 with 2.5% defects allowed
Knowledge check
- Was the sample truly random?
- Was the AQL level pre-agreed with the buyer?