In the fashion or apparel industry, brands conduct inspections of finished garments before accepting them from apparel manufacturers. Given that inspecting the entire lot is neither feasible nor advisable, inspections are typically carried out on a sampling basis.
The percentage of defective pieces deemed acceptable is determined by the Acceptable Quality Level (AQL).
AQL refers to the maximum percentage of defective items that can be considered acceptable during product quality inspections. This level can vary depending on the process, product type, or even specific buyer requirements. With Fashion PLM, brands digitally track AQL compliance, reducing manual errors and improving efficiency.
The following table outlines a sampling plan for final shipment inspections. The AQL level is not uniform across the board; it varies based on the nature of the process, the type of product, and the buyer’s particular standards.
What is Acceptable Quality Level or AQL?
The AQL (Acceptable Quality Level) is the maximum percent defective that for the purpose of sampling inspection can be considered satisfactory as a process average.
Sampling plan Table for shipment inspection:
| Lot or Batch size | Sample size Code Letter | Sample Size | Acceptable Quality Level | |||||
| 2.5 | 4.0 | 6.5 | ||||||
| Ac | Re | Ac | Re | Ac | Re | |||
| 2 – 8 | A | 2 | 0 | 1 | 0 | 1 | 0 | 1 |
| 9 – 15 | B | 3 | 0 | 1 | 0 | 1 | 0 | 1 |
| 15 – 25 | C | 5 | 0 | 1 | 0 | 1 | 0 | 1 |
| 26 – 50 | D | 8 | 0 | 1 | 1 | 2 | 1 | 2 |
| 51-90 | E | 13 | 1 | 2 | 1 | 2 | 2 | 3 |
| 91-150 | F | 20 | 1 | 2 | 2 | 3 | 3 | 4 |
| 151-280 | G | 32 | 2 | 3 | 3 | 4 | 5 | 6 |
| 251-500 | H | 50 | 3 | 4 | 5 | 6 | 7 | 8 |
| 501-1200 | J | 80 | 5 | 6 | 7 | 8 | 10 | 11 |
| 1201-3200 | K | 125 | 7 | 8 | 10 | 11 | 14 | 15 |
| 3201-10000 | L | 200 | 10 | 11 | 14 | 15 | 21 | 22 |
| 10001-35000 | M | 315 | 14 | 15 | 21 | 22 | 21 | 22 |
| Source: ANSI/ASQ Z 1.4 The Sampling procedures and table for inspection by attributes | ||||||||
How to Read AQL Table?
By Lot or Batch Size:
This refers to the total number of pieces in the shipment that the inspector will check. For example, if you receive a shipment of 600 pieces, the batch size will fall within the range of 501 to 1200 pieces, which corresponds to Code ‘J’.
By Sample Size Code Letter:
This code represents a range of batch sizes. For instance, if the code is ‘G’, the lot size falls between 151 and 280 pieces.
By Sample Size:
This is the number of pieces that will be picked from the batch for inspection. The inspector doesn’t check every single piece; instead, they check a small sample of the total shipment.
By AC (Accepted):
This column shows the maximum number of defective pieces that can be found in the sample while still accepting the shipment. If the number of defects is less than or equal to the number in this column, the shipment passes inspection.
By RE (Rejected):
This column shows the number of defective pieces that would cause the shipment to be rejected. If more than the listed number of defects are found, the buyer may reject the shipment and ask for a full inspection of all pieces before re-inspecting.
Now Let’s try a scenario example.
Let’s say you’re inspecting a shipment of 1,000 pieces.
- According to the table, your batch size (1,000 pieces) falls in the range of 501-1200, which corresponds to Code ‘J’.
- The table shows that you need to inspect 80 pieces out of the 1,000 total.
- If you’re using a 2.5 AQL (Acceptable Quality Level), this means:
-
- If you find 5 or fewer defective pieces in your sample of 80 pieces, you should accept the shipment.
- If you find 6 or more defective pieces, the shipment should be rejected.
By inspecting a small sample, you can determine if the overall quality of the batch meets the acceptable standards.
General Sampling Plan Table
| Shipment Lot Size | Single Sampling | ||
|---|---|---|---|
| Level I | Level II | Level III | |
| 9 – 15 | 2 | 3 | 5 |
| 16 – 25 | 3 | 5 | 8 |
| 26 – 50 | 5 | 8 | 13 |
| 51 – 90 | 5 | 13 | 20 |
| 91 – 150 | 8 | 20 | 32 |
| 151 – 280 | 13 | 32 | 50 |
| 281 – 500 | 20 | 50 | 80 |
| 501 – 1,200 | 32 | 80 | 125 |
| 1,200 – 3,200 | 50 | 125 | 200 |
| 3,201 – 10,000 | 80 | 200 | 315 |
| 10,001 – 35,000 | 125 | 315 | 500 |
| 35,001 – above | 200 | 500 | 800 |
FYI, most fashion and apparel products are using Level 1.
Garment Defects: Types and Classifications
Garment defects are classified into three main categories based on their impact on the product’s quality and functionality:
1. Major Defects
A major defect significantly affects the appearance or durability of the garment, making it less aesthetically pleasing or less likely to last. These defects are usually noticeable to the customer and often result in returns or complaints. Examples of major defects include:
- Intermittent stitching
- Large gaps between stitches
- Open seams
These types of defects reduce the garment’s value and are typically not acceptable to the end consumer.
2. Minor Defects
A minor defect is a flaw that does not significantly affect the appearance or function of the garment. These defects are often small and not easily noticed by customers, and they do not prevent the garment from being sold. Examples of minor defects include:
- Small uncut threads
- Slightly uneven edges or seams
These minor issues are generally overlooked by customers and do not warrant returning the product.
3. Critical Defects
A critical defect is the most serious of the three categories, as it affects the basic functionality or safety of the garment. Critical defects make the garment unusable or dangerous to wear. Examples of critical defects include:
- Sharp objects, like metal fragments, left in the clothing
- Missing buttons or zippers
- Absence of care labels or incorrect care instructions
Critical defects usually render the product unsellable and are a major cause for rejection during quality inspection.
