Textile QC Terms Explained: AQL & the 4-Point System

When a fabric order is inspected, the report is full of letters and numbers: AQL 2.5, 4-point system, major vs minor, acceptable quality. These terms decide whether your goods pass or fail — and whether you can reject a shipment. This guide translates the key QC vocabulary so you can read any inspection report with confidence.

AQL — Acceptable Quality Limit

AQL (Acceptable Quality Limit) is the maximum percentage of defective units considered acceptable in a batch. It comes from statistical sampling standards (ISO 2859 / ANSI Z1.4).

• AQL 2.5 — max 2.5% defects accepted; typical for major defects
• AQL 4.0 — max 4.0% accepted; common for minor defects
• AQL 0 / 0.65 — stricter; used for critical requirements

In practice, an inspection plan states the sample size and the accept/reject numbers. If defects found exceed the reject number, the whole lot fails — not just the sample.

The 4-Point System

The 4-point system (also called the American system) scores fabric defects by size and severity:

Defect Length	Points
3 inches or less	1 point
Over 3 to 6 inches	2 points
Over 6 to 9 inches	3 points
Over 9 inches	4 points

Per-yard defects over 4 points are disallowed, and the fabric is graded by points per 100 square yards:

• First quality: 40 points or fewer per 100 sq yd
• Second quality: over 40 points

A common commercial acceptance for apparel fabric is under 20 points per 100 square yards.

Defect severity: critical, major, minor

• Critical defects — render the garment unusable or unsafe (holes, oil stains, wrong composition)
• Major defects — clearly noticeable, affect wear or appearance (shade bands, slubs, miss-weaves)
• Minor defects — slight, acceptable within limits (small knots, slight shade variation)

Each severity has its own AQL: typically critical 0, major 2.5, minor 4.0.

Other terms you'll see on reports

Term	Meaning
Sample size	Rolls/pieces drawn from the lot for inspection
Accept / Reject number	Max defects allowed in the sample before the lot fails
Shade band	Colour variation between rolls or within a roll
GSM check	Fabric weight verification (±5% tolerance standard)
Width check	Measured width vs stated width (±2cm typical)
Roll ticket	Sticker with roll number, length, width and weight

How to use QC terms as a buyer

1. Agree the AQL and points limit in the contract before production — not at inspection time
2. Specify the grading standard (4-point system, points per 100 sq yd)
3. Set severity limits: critical 0, major 2.5, minor 4.0 is the textile default
4. Ask for the raw data, not just pass/fail — the report should show defects found by roll
5. Retain the right to third-party inspection (SGS/BV/Intertek) at the factory before loading

Frequently asked questions

What does AQL 2.5 mean in simple terms?

Up to 2.5% of inspected items may be defective and the lot still passes. Above that rate, the lot is rejected.

What is a good points score for fabric?

Under 20 points per 100 square yards is the common commercial acceptance for apparel; under 40 is first quality.

Who does the inspection?

Either the mill's own QC team (with photos and reports), a third-party company (SGS/BV/Intertek), or your own inspector — most buyers use third-party for first orders.

Do you provide inspection reports?

Yes — every order is inspected in-house per roll, and third-party inspection is welcome at our factory before loading.