Pasteurisation.
https://www.emergency-wash.org/water/en/technologies/technology/pasteurisation
👉🏼 PDF: https://app.box.com/s/xrvo6x9czua59jt7t9xvwlkvoff7j5tg _ Water Pasteurisation uses heat to inactivate pathogenic microorganisms. Most protozoa, bacteria and viruses are inactivated at temperatures between 60–70° C and an exposure time of at least 1 min, though some bacterial spores and protozoan cysts require longer exposure. In practice, water pasteurisation means maintaining water at 70° C for 15 minutes.