AQL Sample Size for Lot 15,000 — GIII Inspection at AQL 4.0

ISO 2859-1:1999 Table II-A · Cross-verified against QIMA reference

Lot size 15,000 units

Inspection level GIII

AQL level 4.0

Code letter N

Sample size 500 garments

Accept if defects ≤ 21

Reject if defects ≥ 22

What this means

For a production lot of 15,000 garments at GIII inspection level with an AQL of 4.0 (minor defects), ISO 2859-1 requires the buyer's QC inspector to pull 500 garments at random from across the lot. If they find 21 or fewer defects, the entire lot is accepted. 22 or more defects means the lot is rejected — the factory must then sort 100% of the lot, repair defective pieces, and re-present for inspection.

Inspection level note: Tightened inspection — used after a failed inspection or for premium brands.

AQL tier: Cosmetic defects — slight thread shading, small uneven hem.

Accept / reject decision table

Defects found in sample	Decision
0 defects	ACCEPT
1 defect	ACCEPT
2 defects	ACCEPT
3 defects	ACCEPT
4 defects	ACCEPT
5 defects	ACCEPT
6 defects	ACCEPT
7 defects	ACCEPT
8 defects	ACCEPT
9 defects	ACCEPT
10 defects	ACCEPT
11 defects	ACCEPT
12 defects	ACCEPT
13 defects	ACCEPT
14 defects	ACCEPT
15 defects	ACCEPT
16 defects	ACCEPT
17 defects	ACCEPT
18 defects	ACCEPT
19 defects	ACCEPT
20 defects	ACCEPT
21 defects	ACCEPT
22 defects	REJECT
23 defects	REJECT

Worked example — your shipment

Suppose your factory has produced 15,000 garments for a buyer who specified GIII / AQL 4.0. The buyer's inspector arrives, opens 5-8 cartons at random, and pulls 500 garments across them.

If the inspector finds 21 defects in those 500 garments → lot ACCEPTED, container ships.

If the inspector finds 22 defects → lot REJECTED. You sort 100% of 15,000 pieces, repair, and re-present in 2-3 days.

How this combination compares

This is the GIII / AQL 4.0 combination — the minor sampling plan for GIII inspection. If your buyer's PO sheet specified different parameters, here are the adjacent plans:

FAQ for Lot 15,000 · GIII · AQL 4.0

What if I find exactly 21 defects?

21 defects = ACCEPT. The accept number is the maximum number of defects you can have in the sample without rejecting. Exactly at the limit is still acceptable.

What if I find 22 defects?

22 defects = REJECT. The reject number is the lowest defect count that fails the lot. There is no "borderline" — anything ≥ 22 triggers a reject.

Can I argue an inspection where I found 22 defects?

You cannot argue the math — the accept/reject thresholds come from the ISO 2859 statistical tables. What you can argue is the classification of each defect. If the inspector marked something as a Major defect that your buyer's spec sheet calls Minor, push back with the spec sheet in writing.

What's the underlying acceptance probability at AQL 4.0?

ISO 2859-1 plans are calibrated so that lots actually at the AQL value get accepted ~95% of the time. So a lot truly at 4.0% defect rate has a 95% chance of being accepted by this plan. Lots at 2× the AQL get rejected most of the time.

Use this in your own QC software

The same logic is published as a free MIT-licensed package:

$ npm install garment-aql-calculator
$ pip install garment-aql-calculator

// Node.js
const { calculateAQL } = require('garment-aql-calculator');
calculateAQL({ lotSize: 15000, inspectionLevel: 'GIII', aql: 4.0 });
// → { codeLetter: 'N', sampleSize: 500, acceptNumber: 21, rejectNumber: 22 }