Final inspection does not check every garment - it checks a random sample and decides for the whole lot. AQL (Acceptable Quality Limit) sets how many defects the sample may have before the lot is rejected.
The four inputs
- Lot size - the number of pieces offered for inspection (the PO or shipment quantity).
- Inspection level - usually General level II for garments.
- AQL value per defect type - commonly 0 for critical, 2.5 for major, 4.0 for minor (buyer manuals differ).
- Plan - single sampling, normal inspection.
Reading the table
- Find the lot size → read the code letter (General II).
- The code letter gives the sample size.
- At the chosen AQL, read Ac (accept if defects ≤ Ac) and Re (reject if defects ≥ Re).
| Lot size | Code | Sample | AQL 2.5 Ac/Re | AQL 4.0 Ac/Re |
|---|---|---|---|---|
| 151-280 | G | 32 | 2 / 3 | 3 / 4 |
| 281-500 | H | 50 | 3 / 4 | 5 / 6 |
| 501-1,200 | J | 80 | 5 / 6 | 7 / 8 |
| 1,201-3,200 | K | 125 | 7 / 8 | 10 / 11 |
| 3,201-10,000 | L | 200 | 10 / 11 | 14 / 15 |
| 10,001-35,000 | M | 315 | 14 / 15 | 21 / 22 |
Worked example
Lot of 2,000 pieces, AQL 2.5 major / 4.0 minor:
- Code K, sample 125 pieces.
- Major: accept up to 7, reject at 8.
- Minor: accept up to 10, reject at 11.
- Critical (for example a needle piece, sharp object, wrong safety label): any one = reject.
The inspector finds 6 major and 12 minor defects → majors pass, but minors fail (12 ≥ 11) → lot rejected. Each defect type is judged separately.
Doing it fairly
- Carton selection: usually the square root of the number of cartons, drawn at random from different parts of the stack.
- Pull pieces from different cartons, sizes and colours.
- Also do carton and packing checks, measurement checks on some pieces, and any function tests (zippers, snaps, pull test) the buyer requires.
- Count defective units by defect type following the buyer's defect list.
Note: AQL 2.5 does not mean "2.5% defects are fine" in every lot. It is the quality level the plan accepts most of the time. Aim for zero - and pass pre-final at a tighter level than the buyer uses.
Key points
- Lot size + General II → code letter → sample size.
- Compare defects found with Ac/Re for each defect type.
- Critical defects: zero tolerance.