One of the most common questions we receive regarding inspections is how defects are classified.
The most important component of product quality is knowing your product. And, that requires detailed product specifications that identify exactly how the item(s) should turn out. Product specifications should also include defect details with classifications that later link to accept/reject determinations during QC checks. Defects can be anticipated, but the list should evolve through observation and consumer feedback. Metrics, as always, are incredibly useful here where continuous improvement is concerned.
Each defect is generally classified as either major, minor or critical. At Pro QC, we use the following general descriptions:
Critical – Any condition found which poses the possibility of causing injury or harm to, or otherwise endangering the life or safety of, the end user of the product or others in the immediate vicinity of its use.
An example of a critical defect might be a sharp plastic bur that has potential to scratch or otherwise harm people. The AQL (acceptable quality level) is generally 0.10 here so any critical defects noted would result in a rejected inspection.
Major – Any condition found adversely affecting the product’s marketability and sale-ability or adversely affecting its required form, fit or function and which is likely to result in the end user returning it to the source from which is was purchased for replacement or refund.
An example of a major defect might be a large (1.5″ or larger) scratch on the exterior front of the product. The AQL is generally tighter for major defects noted, so less is acceptable in a general sample size to achieve a passing result.
Minor – Any condition found which while possibly less than desirable to the end user of the product, does not adversely affect its required marketability, sale-ability, form, fit or function and is unlikely to result in its return to the source from which it was purchased.
An example of a minor defect might be a small (up to 1.5″) scratch on the bottom of the product.
Pro tip: The more specific the product criteria is, the less subjective the nature of the defects. Providing photos as examples is particularly useful. Tracking defects and noting areas for improvement when trends are identified helps improve the overall manufacturing process and end-use value to the consumer.