2.5 AQL - Normal Inspection
| Lot Size | Sample Size | Acc | Rej | Criteria for Continuing Inspection |
|---|---|---|---|---|
| 1 - 8 | All | * | * | N/A |
| 9 - 150 | 8 | 0 | 2 | If 1 defective found, go to S/S of 20** |
| (Cumulative S/S) | 1 | 2 | 2 | If 1 defective found, go to S/S of 20** |
| 151 - 280 | 20 | 1 | 3 | If 2 defectives found, go to S/S of 32 |
| (Cumulative S/S) | 32 | 2 | 3 | If 2 defectives found, go to S/S of 32 |
| 281 - 500 | 20 | 1 | 4 | If 2 - 3 defectives found, go to S/S of 50 |
| (Cumulative S/S) | 50 | 3 | 4 | If 2 - 3 defectives found, go to S/S of 50 |
| 501 - 1200 | 32 | 1 | 6 | If 2 - 5 defectives found, go to S/S of 80 |
| (Cumulative S/S) | 80 | 5 | 6 | If 2 - 5 defectives found, go to S/S of 80 |
| 1201 - 3200 | 50 | 2 | 8 | If 3 - 7 defectives found, go to S/S of 125 |
| (Cumulative S/S) | 125 | 7 | 8 | If 3 - 7 defectives found, go to S/S of 125 |
| 3201 - 10,000 | 80 | 3 | 11 | If 4 - 10 defectives found, go to S/S of 200 |
| (Cumulative S/S) | 200 | 10 | 11 | If 4 - 10 defectives found, go to S/S of 200 |
| 10,001 - 35,000 | 125 | 5 | 15 | If 6 - 14 defectives found. go to S/S of 315 |
| (Cumulative S/S) | 315 | 14 | 15 | If 6 - 14 defectives found. go to S/S of 315 |
| Over 35,000 | 200 | 8 | 22 | If 9 - 21 defectives found. go to S/S of 500 |
| (Cumulative S/S) | 500 | 21 | 22 | If 9 - 21 defectives found. go to S/S of 500 |
An AQL means that as long as a supplier maintains his / her process average (% defective) at the assigned AQL or lower, there is a very high probability that shipments from that supplier (inspected using the Exchange sampling plans) will be accepted. Conversely, there is a very high probability that shipments (inspected using the Exchange sampling plans) will be rejected if a supplier's process average (% defective) remains higher than the assigned AQL.
*Reject only defectives found.
**If lot size is 20 units or less, inspect all and reject only defectives found.
QA Links
Acceptance Quality Levels (AQLs)
All Hardlines Merchandise
Jewelry, Shoes, Clothing, Softside Luggage and any Cut & Sewn Item
Extra Value, Budget, or Entry Price Point Type of Merchandise
Here is how the random sampling works:
Let us say that the shipment or lot size is 2,000 items or pieces. Then:
- Take a sample of 50 pieces at random from this shipment.
- Inspect all 50 pieces.
- If 2 or less defective pieces are found, accept the shipment.
- If 8 or more defective pieces are found, reject the shipment.
- If 3 to 7 defective pieces are found, then take additional 75 samples at random.
- Inspect all 75 samples.
- If a total of 7 or less defective pieces are found, accept the shipment.
- If a total of 8 or more defective pieces are found, reject the shipment.