Acceptable quality level (AQL) sample inspection methods have been proven to be accurate over the long run. However, the quality level of merchandise at destination is sometimes lower than the per shipment inspection results. This may be due to transport, handling, change in environment and/or reliability problems. Buyers are therefore advised to take this into consideration when deciding the AQL levels.

Defect Classification

The client defines the AQL and the maximum number of defective goods allowed in the sample size. Defects detected during visual inspection are usually classified within 3 categories: "Critical", "Major" and "Minor".

• Critical: likely to result in unsafe conditions or contravenes mandatory regulation or rejects by import customs and/or consumers.
• Major: reduces the usability/function and/or sale of the product or if there is an obvious appearance defect.
• Minor: doesn't reduce the usability/function of the product, but is a defect beyond the defined quality standard more or less reduces the sale of the product.

A product with defect(s) is called a defective sample. In the inspection process one defective sample is counted, one for the most serious defect no matter how many defects are found in the said sample.

Clients can specify what points are minor, major or critical in a defect classification checking-list together with the inspection criteria and product specification.