here the auditors like to go in teams to protect themselves from the auditees.
Having had my daily giggle and chuckle, seeing as how we have one system audit a year, we use the team approach. However, as there are multiple audits occurring concurrently, some of my more competent auditors are flying solo while the newer ones and those being assessed are paired up.
The number of auditors is also impacted by the type of audit. ISO internals have the approach mentioned above. 5S are typically pairs (safety issue and more eyes to look around). Standard audits (i.e., documents and process adherence) are solo'd by the supervisor. Safety Hours are in teams of 2-4, but my team branches out on solo adventures and gets back together later to compile notes.

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