If you only need to reference one clause, some national bodies (like BSI or DIN) offer "PDF on demand" or single-user licenses for a lower price than the full ISO version.
This article is for informational purposes only. Always consult the official ISO 3691-4:2020 PDF text and a certified safety engineer before making compliance decisions. Standards are updated regularly; ensure you have the latest version. Iso 3691-4 Pdf