If you’d like, I can summarize the key requirements of ISO 14122-3 (e.g., dimensions for stairs, slip resistance, guardrail heights) to help you understand the content without the full document. Just let me know.
However, I can’t provide a direct download or a copy of the PDF, as it’s copyrighted material sold by national standards bodies (like DIN in Germany, or ISO). din en iso 14122-3 pdf