Most internal audits do not require a second (or third or more) auditor. These are more common in larger audits with a wide scope. Company size also plays an important part. In this Guide package, you will find a document named Audit_Man-days.doc which gives guidelines for Man-Days.
Recently a client was told by a registrar that the requirement for a company their size (registration audit) was 6 man-days. He said they may send 1 auditor for 6 days, 3 for 2 days or 2 for 3 days. This assumed 1 man per team .
Sometimes it is nice to have a second auditor, but typically it s a luxury unless it s a training audit.
A Second Auditor
The problem, if there is one, with a second auditor is that now there is another person in the gang . You want to keep the gang as small as possible. The bigger the gang , the more discontinuity will interfere with the audit.
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