Pre-shipment inspections and AQL: a practical guide to quality control at source

1. Pre-production inspection. Checks raw materials and components before production starts, so problems are caught before they are built into every unit.
2. During-production inspection. Takes place once part of the order is complete, typically early in the run, so issues can be corrected for the rest of the order.
3. Pre-shipment inspection. The most common check. It takes place once production is complete and most of the order is packed, so the inspector sees finished goods in their final packaging.
4. Container loading supervision. Confirms the right goods, in the right quantity, are loaded properly and the container is sealed.

For a first order with a new supplier, consider combining a during-production inspection with a pre-shipment inspection. For established suppliers with a good record, a pre-shipment inspection alone is often enough.

Inspecting every unit of a large order is slow and expensive. Instead, inspectors check a random sample and decide whether the whole lot passes, using the acceptance quality limit (AQL) method set out in the international standard ISO 2859-1.

Two inputs set the sample size: the size of the lot and the inspection level. General inspection level II is the usual default. The AQL you choose for each class of defect then sets how many defects the sample may contain before the lot fails.

These are common starting points for consumer goods, not fixed rules. Tighten them for premium products, and agree them with your supplier in writing before production begins, so a failed inspection is never a surprise.

• Quantity: the number of finished and packed units against the order.
• Workmanship: visual defects such as scratches, stains, loose threads, or poor finishing.
• Conformity: materials, colours, dimensions, and weights against the specification and the approved sample.
• Function and safety: on-site tests suited to the product, from assembly and operation checks to basic electrical safety tests.
• Packaging and labelling: carton markings, barcodes, inserts, and labelling, including South African requirements.
• Transit readiness: carton drop tests and checks that packaging will survive the journey.

An inspection is only as good as the standard it checks against. Before booking one, put together a clear product specification, the approved golden sample, a list of known defects to look for, the AQL levels for each defect class, and any functional tests you want performed. Share it with both the supplier and the inspector.

1. Review the report to understand whether the failure is isolated or systematic.
2. Ask the factory to sort and rework the goods, removing or repairing defective units.
3. Re-inspect before shipment. Agree in advance who pays for re-inspection, usually the supplier.
4. Negotiate only once the facts are clear. Accepting a failed lot at a discount can be reasonable for minor defects, but never for critical ones.

Do not release the balance payment until the goods pass. That payment is your strongest leverage, and it disappears the moment the money is sent.

Quality control at source and standard operating procedures with suppliers are built into every project we manage, as step five of our six-step process. Every Soshida and Balvaro product we sell goes through the same checks.