Internal Audit Resources

What is an Internal Audit?

An internal audit is a systematic, independent, and documented process for obtaining evidence and evaluating it objectively to determine the extent to which audit criteria are fulfilled. Internal audits are a mandatory requirement of ISO 9001, ISO 14001, and ISO 45001.

Why are Internal Audits Important?

• Verify that your management system conforms to requirements
• Identify opportunities for improvement
• Ensure processes are effective and efficient
• Prepare for external certification audits
• Drive continual improvement across the organisation
• Meet the mandatory requirements of ISO management system standards

The Value of Internal Auditing

Internal auditing is far more than a box-ticking exercise to satisfy a certification body. When done well, it becomes one of the most powerful tools an organisation has for driving meaningful improvement across its management system.

First and foremost, internal auditing is a mandatory requirement of every major ISO management system standard. Clause 9.2 of ISO 9001, ISO 14001, and ISO 45001 all require organisations to conduct internal audits at planned intervals. Failing to maintain an effective audit programme is one of the most common nonconformities raised during certification audits.

Beyond compliance, internal audits identify improvement opportunities that might otherwise go unnoticed. Auditors examine processes with fresh eyes, comparing what actually happens on the ground with what procedures and policies say should happen. This gap analysis often reveals inefficiencies, outdated practices, or emerging risks that day-to-day managers have become too familiar with to notice.

Regular internal auditing also prepares your organisation for certification audits. Staff become comfortable with the audit process, evidence is readily available, and any systemic issues are identified and corrected before an external auditor arrives. Organisations with mature internal audit programmes consistently perform better during Stage 2 and surveillance audits.

The programme also builds audit competence within your team. As employees gain experience auditing different departments and processes, they develop a deeper understanding of how the management system works as a whole, making them more effective contributors to system maintenance and improvement.

Finally, internal audits drive corrective action. Every finding, whether classified as a nonconformity or an observation, triggers a structured response that addresses root causes rather than symptoms. Over time, this cycle of audit, correct, and verify creates a culture of continual improvement that extends well beyond the management system itself.

Internal Audit Process

1. Planning — Develop an audit programme and schedule
2. Preparation — Review documentation and prepare checklists
3. Conducting — Perform the audit using opening/closing meetings
4. Reporting — Document findings, NCRs, and observations
5. Follow-up — Verify corrective actions and close NCRs