A process audit is conducted by reviewing procedures and documents, and asking questions of individuals directly involved with the process who perform work that is linked to the process. Next, the auditor determines if the responses are consistent and in alignment with documented policies, objectives, procedures, and records.

If the responses are consistent, this is evidence that the system is functioning properly. If the responses are inconsistent, then the auditor will have to continue to search to determine the reason why this is the case and to collect evidence which supports the inconsistency. This is known as creating and following audit trails. The auditor seeks to find the reason for the inconsistency and then link it back to the management system and a standard so that the supplier can identify and address the inconsistency.

When open-ended questions are asked and audit trails are followed, it is very difficult for a supplier to distract an auditor away from the execution of a thorough, in-depth audit with artificially “sanitized” answers. The only way to prepare for this type of audit is to do the right thing day after day. Most of the time, employees are willing to tell you what they do, even if they are not doing their job correctly at the time of inspection. In addition, by investigating the linkages, one can determine if the processes are operating in a manner that is consistent with stated policies and objectives.

A process audit is a powerful tool. It allows the auditor to go beyond inspecting the cosmetic issues in a plant. The process audit is designed to understand how the plant functions day to day. Cosmetic issues, such as determining if HACCP plans are signed and up to date are still audited. However, these issues become part of the audit, and are not the primary focus. When an auditor sees a potential finding on a cosmetic issue, this sends a signal to the auditor.