Network Access for Internal Audit

Does your Internal Audit manager or team have automatic read access to your organization's network files, or do you have to submit a request to access files and systems for each audit? I would prefer to have ongoing read access to network files which appears to be permitted by policy, however, there seems to be some concern with this approach. I am wondering if there is an industry standard regarding network access for internal auditors. 

Thanks for sharing how your organization handles this access.