Internal Auditing specifics

“Do you have a white paper or any documented evidence that will support the case of those requirements relating to ISO auditing that you an share - especially ALL clauses and over what time span?"

Answer:

The requirement about auditing all clauses every year it is not in ISO 9001 but in the contract that you sign with the certification body as one of the commitments required. Same for at least one management review per year.

“the internal auditing process needs to be audited by a qualified person independent of the activity”

Answer:

Any function relevant to the quality management system must be performed by a competent person. It is up to each organization to determine internal auditor competence requirements. About independence, please check ISO 9000:2015 definition 3.13.1 where one can read that an audit is “systematic, independent and documented process”. That is why auditors should not audit their own work.

The following material will provide you more information:

• ISO 9001 – Five Main Steps in ISO 9001 Internal Audit - https://advisera.com/9001academy/knowledgebase/five-main-steps-in-iso-9001-internal-audit/
• free online training ISO 9001:2015 Internal Auditor Course
  – https://advisera.com/training/iso-9001-internal-auditor-course/ 
• book - ISO Internal Audit: A Plain English Guide - https://advisera.com/books/iso-internal-audit-plain-english-guide/