Based on the latest IATF sanctioned intepretation of IATF clause 7.2.3 Internal Auditor competency, "At a minimum, manufacturing process auditors shall demonstrate technical understanding of the relevant manufacturing process(es) to be audited, including process risk analysis (such as PFMEA) and control plan." We approach manufacturing process audits in two ways. We conduct layered process audits, and then we have members of our Quality group that perform process audits. For layered process audits, a standard checklist is used, and none of the questions directly reference the control plans or the PFMEA's. There are multiple layers of employees that participate in the layered process audits, some would be able to demonstrate a technical understanding of the PFMEA and control plan, but not all. For the members of the Quality group performing process audits, they also use a standard checklist for all of our production lines. They also perform another set of process audits in which they audit a control plan vs actual practice. PFMEA's are not audited by this layer of the Quality group. This layer of the Quality group could easily demonstrate a technical understanding of control plans, but not PFMEA's. We have a reverse PFMEA process which we feel shows evidence that we audit our PFMEA's, and the group involved in this activity would be able to demonstrate a technical understanding of PFMEA's. My concern is that we have several employees involved in what we would define as manufacturing process audits that use standard checklist, and understand what is on that checklist, but they might not be able to demonstrate a technical understanding of control plans or PFMEA's. Suggestions?