Boiling.
https://www.emergency-wash.org/water/en/technologies/technology/boiling
👉🏼 PDF: https://app.box.com/s/sjp5nlra2qf1940ex9e7d8hbu819mnkv _ Boiling water is the oldest and most used method to disinfect small quantities of water at the household level worldwide. Boiling water inactivates all microorganisms including bacteria, protozoa and viruses, but does not remove turbidity or chemical contaminants from drinking water.