Blog · 2026-09-06

"Inspection before the balance - how much should actually be sampled?"

The most common failure in inspection is not skipping it, but paying the balance before settling how many units to sample, against what standard, and what records to keep.

How the sampling is set

Industry figures show AQL 2.5 is commonly used as the major-defect line and AQL 4.0 as the minor-defect line, based on ISO 2859-1; a 5,000-unit order is typically sampled at 200 units. For sensitive categories such as infant products and auto parts, buyers have started asking for AQL 0.65 or lower. For the same batch, the AQL level directly determines how many units are sampled and how many defects are allowed. Sampling is not "looking at a batch", but a statistical method: sample size, acceptance line and allowable defects - all three together make one valid inspection. Their value is that the sampling rate can be written into the contract and negotiated, rather than decided on inspection day - settle it in advance, and on the day you only have to answer "pass or fail".

What the inspection should leave behind

The value of an inspection is not that someone looked at the goods that day, but the record it leaves: how many units were sampled, which defects were found, which AQL level was applied, and who signed. Without a record, an inspection is a one-off verbal conclusion - hard to trace once the container is loaded, and hard to use as grounds for rejection or deduction.

How it relates to the balance

Write "inspection passed" as a precondition for the balance, rather than "we will look at it together after loading"; a common bad habit is loading first and inspecting afterwards, which hands over all your leverage. For sensitive categories, either raise the sampling rate or write a stricter AQL into the contract. As for which level to set, agree the basis in the glossary with the supplier, then fold it into the inspection section of the verification checklist. One easily missed point: who does the inspection. A report issued by the supplier itself and a sample drawn by an independent third party against an agreed standard carry very different weight. The later and more rushed the sampling, the more likely it is to be a formality; move the inspection earlier and keep the money in hand, and you still have something to negotiate with.