What Is an Audit in Process Improvement?

In process improvement, an audit is a planned, independent check that a process is being run the way its standard says it should be — and that the evidence proves it. The auditor compares actual practice against a documented reference: a control plan, a standard operating procedure, a regulation. The output is not blame but a list of gaps, each with an owner. Done well, an audit finds drift before the customer does; done badly, it teaches people to perform compliance for one day a year.

How it’s used

Audits come in layers. A product audit examines output against specification. A process audit examines how the work is performed against the standard. A system audit examines whether the whole management system — documents, training, records, corrective action — functions as designed. Manufacturing has added layered process audits: short, frequent checks run by different levels of the organization on a rotating schedule, from team leads weekly to plant managers monthly.

In Six Sigma, audits belong chiefly to the Control phase. After a project standardizes an improvement, an audit schedule is the mechanism that keeps it standardized — the periodic, sampled answer to the question every sponsor eventually asks: is the fix still in? The audit is what stands between a successful project and the slow, unmeasured return of the old way of working.

An illustration: holding the gain

A project team overhauls order entry and cuts input errors sharply. The control plan is in place; the project closes. Six months later, a monthly process audit samples ten orders and finds a new failure pattern: two recent hires skip the address-verification step, because the training checklist was never updated to include it. The finding gets an owner, the checklist gets the step, and the metric never has time to slide far enough for a customer to notice. That is the audit working — not catching villains, catching drift. Multiply the pattern across every closed project and the audit schedule becomes the quiet infrastructure of an improvement program: unglamorous, inexpensive, and the reason gains from two years ago are still gains.

• Audit against the written standard, never against the auditor’s taste
• Short and frequent beats exhaustive and annual
• Every finding needs an owner and a date, or it is a remark, not a finding
• Verify corrective actions later — a finding is closed only when the fix is proven
• Repeat findings indict the standard or the training, not the people

An audit doesn’t create discipline; it reports how much was there before the visit was announced.

Audits and control plans close out the DMAIC roadmap in our Green Belt program — $299, about 35 hours, a 100-question proctored exam, and lifetime access. Black Belt training extends the skill from auditing a single process to auditing an entire improvement program.