AQL Sample Size for Lot 30,000 — GII Inspection at AQL 2.5

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

Lot size 30,000 units

Inspection level GII

AQL level 2.5

Code letter M

Sample size 315 garments

Accept if defects ≤ 14

Reject if defects ≥ 15

What this means

For a production lot of 30,000 garments at GII inspection level with an AQL of 2.5 (major (standard) defects), ISO 2859-1 requires the buyer's QC inspector to pull 315 garments at random from across the lot. If they find 14 or fewer defects, the entire lot is accepted. 15 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: Default for garment buyer QC — most shipments inspected here.

AQL tier: Industry-standard major defect AQL — broken stitch, open seam, wrong measurement.

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	REJECT
16 defects	REJECT

Worked example — your shipment

Suppose your factory has produced 30,000 garments for a buyer who specified GII / AQL 2.5. The buyer's inspector arrives, opens 5-8 cartons at random, and pulls 315 garments across them.

If the inspector finds 14 defects in those 315 garments → lot ACCEPTED, container ships.

If the inspector finds 15 defects → lot REJECTED. You sort 100% of 30,000 pieces, repair, and re-present in 2-3 days.

How this combination compares

This is the GII / AQL 2.5 combination — the major (standard) sampling plan for GII inspection. If your buyer's PO sheet specified different parameters, here are the adjacent plans:

FAQ for Lot 30,000 · GII · AQL 2.5

What if I find exactly 14 defects?

14 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 15 defects?

15 defects = REJECT. The reject number is the lowest defect count that fails the lot. There is no "borderline" — anything ≥ 15 triggers a reject.

Can I argue an inspection where I found 15 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 2.5?

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 2.5% 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: 30000, inspectionLevel: 'GII', aql: 2.5 });
// → { codeLetter: 'M', sampleSize: 315, acceptNumber: 14, rejectNumber: 15 }