You can download the PDF version of ICAO Doc 9811 from the official ICAO website:
Q: Where can I download ICAO Doc 9811 PDF? A: You can download the PDF version of ICAO Doc 9811 from the official ICAO website: https://www.icao.int/safety/aviation-medicine/Docs/9811.pdf icao doc 9811 pdf link
https://www.icao.int/safety/aviation-medicine/Docs/9811.pdf You can download the PDF version of ICAO