ISO 17020 specifies requirements for the competence of bodies performing inspection and for the impartiality and consistency of their inspection activities. Certification bodies accredited to ISO 17065 may rely on inspections performed by bodies accredited to ISO 17020. The two standards are strongly related because an inspection body may inspect a product to determine if it satisfies the requirements for a product certification scheme offered by a certification body.

ISO 17025 specifies the general requirements for the competence, impartiality and consistent operation of laboratories. Certification bodies accredited to ISO 17065 may rely on testing performed by laboratories accredited to ISO 17025. Testing may be needed to determine if a product satisfies the requirements for a product certification scheme offered by a certification body.