In brief
A supplier audit is a systematic on-site examination at a supplier, in which a customer assesses quality capability, processes and reliability.
Contents
What is Supplier audit?
In a supplier audit, a buyer checks whether an existing or prospective supplier can meet its requirements on a lasting basis. Technically, it is a second-party audit: the customer audits the supplier itself or commissions a third party to do so. It is distinct from internal audits (first party) and from certification audits by independent bodies (third party). ISO 19011 (DIN EN ISO 19011) provides recognised guidelines for conducting audits.
Three types are common: the system audit looks at the management system as a whole, the process audit at individual processes such as production, inspection or storage, and the product audit at whether finished parts conform to drawing and specification. Procedure: planning with a checklist, execution on site or as a remote audit, a report with findings and finally a corrective action plan whose implementation is followed up. The result often feeds into a classification of the supplier.
In spare parts procurement, audits are particularly worthwhile for suppliers that deliver critical or safety-related parts, manufacture to drawing, or are to be qualified as a second source for discontinued components. The audit then examines, for example, incoming inspection, traceability, storage conditions and the handling of non-conforming parts.
In practice: maintenance and procurement
Plan audits on a risk basis: suppliers of critical spare parts and new sources first, rather than all suppliers across the board. Define in advance which evidence (inspection records, certificates, calibration records) is to be reviewed on site, and agree binding deadlines in the action plan for any findings.
Synonyms and abbreviations: supplier quality audit · second-party audit · on-site supplier assessment · supplier process audit
Frequently asked questions
What is the difference between a supplier audit and supplier evaluation?
Supplier evaluation assesses a supplier continuously using key figures such as delivery reliability, quality and price, mostly from existing data. A supplier audit, by contrast, is a targeted examination on site or as a remote audit that looks directly at processes and evidence. Audits often provide the basis for an initial evaluation or clarify anomalies found in ongoing evaluation.
What types of supplier audit are there?
A distinction is usually made between system audits, process audits and product audits. The system audit examines the management system as a whole, the process audit individual processes such as production or inspection, and the product audit whether parts conform to the specification. Depending on the reason, an audit can be announced, short-notice or remote, with document review and a video walk-through.
How does a supplier audit work?
First, the scope, date and checklist are defined and communicated to the supplier. On site there is an opening meeting, a walk-through, interviews and a review of documents and records. Findings are discussed at the closing meeting. The audit team then prepares a report, the supplier submits a corrective action plan and its implementation is followed up, with a follow-up audit if necessary.
When is a supplier audit worthwhile?
An audit is worthwhile above all when approving new suppliers, for parts with a high failure or safety risk, after repeated complaints, or when production is relocated to another site. For non-critical catalogue parts, a self-assessment with supporting evidence is often sufficient. The key is to align the effort with the risk of the part concerned.