How to become a certified ISO internal auditor
Implementing ISO‑compliant management systems can deliver significant benefits for organisations of all sizes. Whether focused on quality, safety, information security, environmental management, or emerging areas such as artificial intelligence, achieving certification to an ISO standard helps businesses drive continual improvement, demonstrate strong performance, and show a clear commitment to best practice.
Before an organisation can be certified by an independent third party such as DNV, its management system must first be properly developed and implemented. This process includes carrying out internal audits conducted by trained ISO internal auditors who understand both the requirements of the relevant ISO standard and the organisation’s specific processes and structure.
What is an ISO auditor? Meaning and definition
Strictly speaking, there is no formal role known as an “ISO auditor”. However, the term is commonly used to describe professionals who have the knowledge and expertise to assess an organisation’s processes and management systems against internationally recognised ISO standards. These professionals can operate either as internal or external auditors:
- Internal auditors typically work within the organisation seeking certification. They assess their own management systems to ensure compliance with ISO requirements and help identify areas for improvement before an external audit takes place. By performing internal audits, they play a crucial role in maintaining conformity and preparing the organisation for certification.
- External auditors, on the other hand, are employed by independent certification bodies such as DNV. They conduct impartial evaluations to verify whether an organisation’s management system meets the requirements of specific ISO standards. To ensure competence and impartiality, external auditors must meet the criteria set out in ISO/IEC 17021, the international standard that defines the principles and requirements for organisations providing auditing and certification services.
ISO itself does not certify auditors – its role is to develop and publish management system standards. Individuals wishing to become an ISO-competent auditor can achieve personal certification through bodies such as IRCA, provided they complete all required training and successfully pass the associated examinations. Certification bodies like DNV also deliver a wide range of internal auditor courses tailored to specific ISO standards and skill levels, like our ISO 9001 internal auditor and ISO 45001 Internal Auditor training courses.
What's the difference between an internal auditor and an internal lead auditor?
Audits of an organisation’s management systems must be conducted regularly to ensure certification is maintained. Internal audits are typically carried out more frequently by the organisation’s own audit team, which generally consists of several auditors and a designated lead auditor. These internal assessments may focus on specific risk areas or particular aspects of the management system. To retain certification, external audits are performed by the certification body and are usually undertaken on an annual basis.
Within the context of management systems, the distinction between an internal auditor and lead auditor lies in the scope of their responsibilities and the depth of their auditing experience. A lead auditor possesses a greater knowledge of both the audit process and the specific ISO standard being assessed, and they are responsible for leading the audit team.
Both internal and lead auditors share the goal of improving organisational process and ensuring compliance with the applicable ISO standard(s). Typically, a lead auditor begins their career as an internal auditor, gaining practical experience across multiple audits before progressing to a comprehensive lead auditor training course. DNV's ISO 9001 Lead Auditor and ISO 14001 Lead Auditor training courses are tailored to individual ISO standards to ensure that auditors develop the specialist competence required.
How to become an ISO auditor: steps and requirements
Becoming an ISO auditor involves completing a series of steps and requirements designed to ensure you gain the necessary knowledge, skills, and practical experience needed to effectively perform audits against a specific standard.
Training and On-the-Job Experience
The journey typically involves both formal training and on-the-job experience related to the relevant ISO standard and management system. Industry knowledge is also highly beneficial, and for external ISO auditors, understanding the sector in which a company operates is often a formal competency requirement.
Building an Understanding of ISO Standards
Developing a strong understanding of the ISO standards you will be auditing requires studying the standards themselves, alongside any guidance documents, interpretations, and sector-specific requirements.
Importance of Training Courses
Training courses, such as those offered by DNV, provide essential knowledge of the audit process and help you translate theoretical knowledge into practical audit skills. These courses often conclude with an examination to verify that attendees have achieved the required level of understanding before the course can formally be completed.
Achieving Recognition
Depending on the training provider, successful completion of the exam may grant an internationally recognised certificate. If not, auditors who meet the necessary experience requirements and pass an approved examination can apply for registration with organisations such as the International Register of Certified Auditors (IRCA). This is a well‑known route for both internal auditors and lead auditors seeking professional recognition.
Continuous Professional Development (CPD)
Auditors are expected to maintain and develop their competence through continual professional development (CPD). This may involve attending additional training courses, participating in industry events, or keeping up to date with revisions to standards and best practice.
What are the advantages of becoming a certified internal auditor?
Pursuing certification as an internal auditor offers a wide range of benefits. Certification reflects a high level of competence and professionalism, demonstrating that the auditor is committed to maintaining quality, objectivity, and best practice.
Certified internal auditors play a vital role in ensuring continual compliance and driving improvement. Their work supports an organisation’s ability to maintain ISO certification, strengthen internal processes, and manage risks effectively. Earning an internal auditor certificate is widely recognised across industries and can significantly enhance an individual’s career prospects and credibility.
In essence, becoming a certified internal auditor is more than achieving a professional title. It represents a commitment to continuous learning, ongoing development, and contributing to the highest standards of organisational performance, benefiting both the business and the individual.
