PDF/A-Compliant Guide

NSF-PAR, among other, requires PDF/A documents. They prodive some indications on how to produce such documents, but unfortunately only using Microsoft Word Documents and Adobe Acrobat Professional.

From a .tex source code

If you can access a .tex source code, then you can use latex2pdfa.

From a .pdf

If you can only access the .pdf (for example of the published version), then you can use OCRmyPDF, for example with

ocrmypdf --tesseract-timeout=0 --skip-text input.pdf output.pdf

so that your document is not "OCRized".