Pre-shipment inspection in China: what is checked and how AQL works
Short answer: A pre-shipment inspection (PSI) is a random-sample check done at the factory when at least 80% of the order is finished and packed. The inspector counts quantity, checks workmanship, function, measurements, packaging and labels, and decides pass or fail with AQL sampling (ISO 2859-1). Book it before you pay the balance, so the factory fixes problems while it still has your money to earn.
When to book the inspection
Book a pre-shipment inspection when at least 80% of the goods are finished and at least part of them are packed in export cartons. Earlier than that, the inspector cannot see the real packing. Later, there is no time to rework anything before the ship date. Give the factory and the inspector about 3 to 5 working days of notice.
For a first order or a complex product, add a during-production inspection when 20 to 30% of the goods are made. It catches problems with materials or assembly while they are still cheap to fix.
What the inspector checks
- Quantity: finished and packed units against the order.
- Workmanship: scratches, stains, loose threads, bad welds, colour differences against the approved golden sample.
- Function and safety: the product does what it should; electrical items get basic safety and power-on tests.
- Measurements and weight: against your specification sheet, with tolerances.
- Packaging and labelling: retail packaging, barcodes, warning labels, country-of-origin marks and carton shipping marks.
- Carton drop test: a packed carton is dropped on its corner, edges and faces to see whether the product survives transport.
You receive a report with photos of every check and a clear pass, fail or pending result, usually the same day or the next morning.
How AQL sampling works
Nobody checks every piece of a large order. AQL (Acceptance Quality Limit) sampling, defined in ISO 2859-1, tells the inspector how many pieces to pick at random and how many defects are acceptable. Most consumer goods use general inspection level II with these limits:
- Critical defects (unsafe or illegal): 0 allowed.
- Major defects (the customer would return it): AQL 2.5.
- Minor defects (small cosmetic issues): AQL 4.0.
Worked example: 3,000 mugs
For an order of 3,000 pieces, level II gives sample size code K, which means the inspector checks 125 pieces.
| Defect type | AQL | Pass if defects are at most | Fail at |
|---|---|---|---|
| Critical | 0 | 0 | 1 |
| Major | 2.5 | 7 | 8 |
| Minor | 4.0 | 10 | 11 |
If any limit is exceeded, the lot fails. The factory then sorts or reworks the goods and a re-inspection is booked before you release the balance payment.
What to prepare before the inspection
- The approved golden sample, kept at the factory and photographed.
- A specification sheet with dimensions, materials, colours (Pantone codes) and tolerances.
- Your defect list: what counts as critical, major and minor for this product.
- Packaging artwork, barcode files and carton marking instructions.
The clearer these are, the fewer arguments you will have with the factory after a failed result.
Questions buyers ask
Who pays for a re-inspection if the goods fail?
Many buyers write into the contract that the factory pays for any re-inspection caused by a failed result. Agree this before production starts.
Can you inspect goods I bought on Alibaba or 1688?
Yes. An inspection can be arranged for any order, whoever found the supplier. You only need the factory address, a contact person and the product details.
Is a pre-shipment inspection enough on its own?
For a repeat order with a known factory, often yes. For a first order, combine it with a factory audit before you pay the deposit and a during-production check.
Does the inspection replace product certification?
No. An inspection checks quality against your sample and specification. Lab tests and certificates such as CE, FCC or CPC are separate and must be arranged with an accredited laboratory.
Need an inspector at your factory? Message us on WhatsApp with the product, quantity and factory city, or send the details through our form.