Third-party inspection in China: types, AQL, audits and cost

What is third-party inspection, and why do buyers use it?

Inspection means an expert examining a product, material or process and judging whether it conforms, unlike a laboratory test or a certificate [1]. ISO/IEC 17020 sets the requirements for inspection bodies' competence, impartiality and consistent operation [2]. ‘Third-party’ describes who the inspector answers to: the factory's QC is first-party, your own staff are second-party, and a third-party inspection company or agency is independent of both. The standard calls this Type A, a body that takes inspection work from outside clients and reports back to them [1]; its 2026 revision keeps Type A and groups the rest as ‘Type non-A’ [2].

Buyers use it for leverage and evidence. When the balance is due before shipment, the final inspection is your last chance to hold payment, and a report from a body with nothing to gain is evidence for a retail customer, a bank or a claim. That independence is why third-party verification matters; the inspection itself does not improve the factory's process.

Inspection is one of three related services. Testing measures characteristics by a set procedure, often in laboratories accredited to ISO/IEC 17025; certification is a third-party attestation by bodies accredited to ISO/IEC 17065 for products or ISO/IEC 17021-1 for management systems [3].

Which inspection do you need, and what does each one catch?

Book by risk: a new factory, fabric or style justifies an early check; a repeat style from a factory with a clean record may need only the final one.

How does AQL sampling work, and what does a pass prove?

A final inspection uses lot acceptance sampling: in a single sampling plan the inspector examines n randomly drawn pieces, and the lot is accepted only if the defectives found do not exceed the acceptance number c [4]. The usual AQL tables descend from the US military standard MIL-STD-105, adopted as ANSI Z1.4 and as ISO 2859 [5]; ISO 2859-1 was revised in 2026 and includes rules for switching between normal, tightened, reduced and skip-lot inspection [6].

You do not pick n and c. You set an AQL for each defect class and an inspection level; the lot size and level give a code letter, and the table for your AQL gives the sample size with its accept and reject numbers [5]. The standard has three general inspection levels and four special ones [5], so write the standard, edition, level and AQLs into the booking, and define the classes yourself: critical for safety or legal faults such as a needle fragment, major for faults a customer would return, minor for small cosmetic flaws.

AQL stands for acceptance quality limit [6]; older texts say acceptable quality level. A plan gives lots at or better than the AQL a high chance of acceptance [4], and the scheme aims to hold the producer's process average there over many lots [6]. In NIST's worked example, a plan with a sample of 52 and an acceptance number of 3 accepts a lot that is 5 per cent defective with probability 0.739, and one that is 12 per cent defective with probability 0.115 [7]. A pass at AQL 2.5 means the sample stayed within the acceptance number, not that at most 2.5 per cent of the goods are faulty.

What should an inspection report contain?

A usable third-party inspection report lets someone who was not there reach the same decision: the order and quantities produced and packed; the sampling settings actually used; every defect counted, classified and photographed; measurements per size against tolerance; on-site tests and packing checks; a pass, fail or pending verdict with reasons; and the inspector, date and site address. Build the inspection form, the checklist used on site, from your booking pack.

What is a factory audit, and how is it different?

A factory audit, also called a supplier or vendor audit, asks whether a supplier should make your goods at all. It matters because a wrong factory cannot be inspected into a right one: a failed lot can be reworked, but a site that quietly subcontracts or cannot sew stretch fabric to tolerance will fail again. Retail customers may also require audits before listing your products.

Social audit schemes set their own rules; amfori BSCI, for example, says it is not a certification. Its audit asks 81 questions, answered from observation, interviews and documents, on a two-year cycle, and a C, D or E grade requires a follow-up within two to twelve months [8]. Full reports are open only to members and the audited supplier, so ask the factory for its latest report [8].

What should a supplier audit checklist cover?

A supplier audit checklist lists what the auditor must verify on site and the evidence expected for each item. For a factory audit in China, two checks earn their keep: that the company on your contract operates the site you visit, and whether any process goes to another workshop.

For an Excel audit form, use one row per requirement with columns for area, requirement, evidence seen, result (yes, partial, no, not applicable), severity, photo, corrective action, owner and due date; a sample row reads ‘needle log missing on one line; major; start the log and brief line leaders’. The audit report format adds a cover sheet (legal name, address, date, auditor, scope) and a section summary; one critical finding should outweigh a good average.

How do you book a third-party inspection?

Send a pack, not just a PO number: the golden sample (the approved production sample, sealed and signed, with a twin kept at the factory); the tech pack; the measurement chart with a tolerance for each point of measure; your defect list; the sampling standard, edition, level and AQLs; packing requirements such as carton marks, polybag warnings and assortment; the on-site tests; and the factory's address and contact.

Fix the date against a readiness rule, such as production finished and an agreed share of cartons packed, confirmed by the factory in writing; a wasted visit still costs a man-day. Agree in the contract who pays for re-inspection after a fail, what a pending verdict triggers, and that you receive the report no later than the factory.

How do you check an inspection body before hiring it?

Accreditation is the independent confirmation that an inspection body is competent and impartial, granted against ISO/IEC 17020 [3]. Confirm the accreditation certificate and scope in the accreditation body's online directory; not every accreditation body has signed the Global ACI mutual recognition arrangement [3]. As checked on 22 September 2026, Global ACI has carried out the former roles of ILAC and IAF since 1 January 2026, and documents may still show the older ILAC or IAF marks during the transition [3]. In China, the national accreditation body, CNAS, accredits inspection bodies under criteria based on ISO/IEC 17020 [9].

On the scope, check that it covers garments, textiles or consumer goods, that the body is Type A for that work [1], and that it is current; accreditations granted before the 2026 revision [2] may still cite the 2012 edition [9].

What drives the cost of third-party inspection?

Inspections are usually quoted per man-day plus travel, so cost follows time; this guide gives no prices.

What should you put in writing?

Write the inspection plan into the purchase contract: the inspections, sampling settings, defect list, golden sample reference, readiness rule, who pays for re-inspection, and that shipment and balance payment depend on a passed final inspection or your written waiver. File audit findings with the order, so the next one starts from the last corrective action plan.

SEAMDANCE runs final inspection at AQL 2.5 on every style it ships, whichever factory makes it. If you also appoint an independent inspection body, give it the same golden sample, measurement chart and defect list, so both checks judge the goods against one standard.

Inspection company, agency or individual inspector in China: who can do the job

Whether you search for an inspection company, agency, service or inspector, the choice in China comes down to who will stand in the factory for you and whom they answer to. Only an inspection body that takes work from outside clients and returns its reports to them is third-party, Type A; a body that belongs to the organisation making or selling the goods is Type B or C [1]. The providers you will meet range from large international testing, inspection and certification groups to smaller accredited bodies, unaccredited agencies and individual inspectors; the table shows what each can prove.

For a body registered in China, ask for its CNAS accreditation certificate and scope. CNAS lists commodity inspection among the fields in which it accredits inspection bodies [11], and it publishes suspensions, cancellations and withdrawals, including those that cover only part of a scope [12]. Check that the legal entity named on your booking and on the report is the one named on the certificate, then confirm it in the directory [3].

Book around China's public holidays. As checked on 22 September 2026, the State Council's notice for 2026 sets 25 to 27 September for the Mid-Autumn Festival and 1 to 7 October for National Day, with Saturday 10 October a working day [13]. That notice was issued on 4 November 2025, so the 2027 dates, including the Spring Festival break, will come in a later notice; treat a readiness date just after a long holiday with caution.