Remediating accessibility issues in PDFs requires a lot of extra care towards the design:
Fixing all of these issues can be challenging, however if you have the original source document you can save time with PDF cleanup. Microsoft Office has built-in features that can optimize and preserve the accessibility of your document. Reference the WebAIM article on creating an accessible Microsoft Word document:
Note: You can also reference the library guide on Microsoft Word Accessibility.
In Microsoft Word, go to the Review tab and select the Check Accessibility tool. This tool will inspect your document for any detectable accessibility issues.
After addressing the issues, you can convert your Microsoft Word document to a PDF. Go to File > Save As and choose your file type as PDF.
Note: before converting a Google Doc to PDF, first convert the Google Doc to Microsoft Word. In comparison to Microsoft Word, Google Docs does not preserve accessibility features as well when converting directly to a PDF.