The way in which the audit process is carried out is defined in ISO 16919:2014, which is available from ISO and also from CCSDS site. This is designed to follow the ISO approach to audits as part of a process of continuous improvement.
The advantage of doing it in this way is that ISO has a well proven mechanism of checks at every stage following a hierarchy of standards:
- Auditors are checked and accredited by accreditation bodies, according to standards such as ISO 16919
- the accreditation bodies themselves must be accredited according to ISO 17021
- and so on
Following these methods enables the set up of an international network of audit organisations which can conduct audits which are impartial and consistent, supporting international trade and cooperation.