How labs qualify a supplier

A laboratory that buys a material is relying on someone else’s process. Supplier qualification is how it decides, on evidence, whether that reliance is justified, and how it keeps checking once the decision is made. The output is not a feeling about a source. It is a record: what was required, what was examined, what was found, and who approved the result.

Where the requirement comes from

ISO/IEC 17025 requires a laboratory to define its requirements for externally provided products and services, to evaluate and select providers against those requirements, and to monitor their performance. Good manufacturing practice guidance, including ICH Q7, describes supplier evaluation and approval for materials used in manufacturing, along with the testing that incoming lots should receive. The details differ between sectors, but the shape is the same: state what you need, check that a source can provide it, and keep checking.

Defining what is needed

Qualification starts before any source is contacted. The laboratory writes down what the material must meet: the specification, including the grade and the tests that matter for its use; the documents that must come with each lot, such as a certificate of analysis carrying the lot number, test methods, results and a signature; the packaging and labeling expected; and the storage and transport conditions the material needs. Without that list, there is nothing to qualify a source against, and the decision becomes a matter of reputation.

The steps of qualification

1. Questionnaire. The source is asked about its quality system, its certifications or accreditations, its manufacturing or repackaging operations, its testing capability, its practice on notifying changes, and its complaint handling.
2. Document review. Certificates of accreditation or certification are checked for scope and validity. Sample certificates of analysis are compared against the laboratory’s requirements. Specifications and safety data sheets are obtained and filed.
3. Audit. For materials whose quality directly affects results, an audit examines the source’s operations and records, on site or by documented remote review. Lower-risk materials may be qualified on documents alone, with the reasoning recorded.
4. Trial lots. One or more lots are received and tested in full against the specification, and the results are compared with the source’s own certificates.
5. Approval. The quality function records the decision and adds the source to the approved list, for the named materials only.

Distributors and the original maker

Many materials reach a laboratory through a distributor rather than directly from the manufacturer. Qualification then has two parts. The distributor is evaluated for how it stores, handles and documents the material, and the laboratory needs to know who made it. A certificate of analysis that originates with the manufacturer should arrive unaltered, or with any repackaging and retesting clearly identified as such. A distributor’s certificate that names no manufacturer and no original lot breaks the chain the qualification is meant to establish.

Keeping a source qualified

Approval is not permanent. Each incoming lot is checked: the certificate against the specification, the lot number on the certificate against the label, the condition of the packaging, and any temperature records from transit. Laboratories commonly perform at least an identity test on every lot and full testing at a defined frequency, increasing the testing if problems appear. Nonconformances are recorded against the source, and the source is re-evaluated on a schedule and after any significant problem.

Changes are where most of the risk sits. A source that changes its manufacturing site, its process or its own suppliers may still meet the specification, or may not. A written agreement that requires notice of such changes, and a procedure for assessing them when the notice arrives, is what keeps a qualification current rather than historical. A source that cannot or will not give notice of changes is a source whose past performance says less about its next lot.

Disqualification needs a procedure as well. When a source is removed from the approved list, the record should say why, which materials are affected, and what happens to stock already received. Lots on the shelf from a disqualified source are not automatically unusable, but they need a decision, and the decision belongs in the file beside the evidence that prompted it.