What is a requirement regarding internal audit according to ISO standards?

The requirement that the scope of the audit should be defined is essential within the ISO 9001 framework. Defining the scope of an internal audit ensures that the auditor has a clear understanding of what processes, departments, or activities will be examined during the audit. This structured approach promotes a comprehensive evaluation of the Quality Management System (QMS) and helps to identify areas for improvement.

By clearly outlining the scope, the internal audit can focus on specific objectives and areas of concern, ensuring efficient use of resources and relevant findings that align with the organization’s quality goals. Additionally, a defined scope allows for better planning and execution of the audit, fostering consistency and adherence to established requirements.

In contrast, while the other options might suggest potential practices, they do not align with the fundamental framework established by ISO standards. For example, recording all interviews could be impractical and not mandated, an audit plan serves as a critical guide rather than an optional document, and informal audits do not provide the rigor and reliability necessary for a structured QMS evaluation.