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[[Image:boiling water.jpg|thumb|right|250px|Boiling water for purification. <br>Photo: [http://kopernik.info/en-us/theblog/201012 Kopernick]]]

Boiling is considered the world’s oldest, most common, and one of the most effective methods for treating water. If done properly, boiling kills or deactivates all bacteria, viruses, protozoa (including cysts) and helminths that cause diarrheal disease. Pathogens are killed when the temperature reaches 100 degrees Celsius. In high-lying areas, where the boiling temperature of water can be as low as 80 degrees Celcius, a longer boiling time is necessary to kill all pathogens.

==Manuals, videos, and links==

[http://www.cawst.org CAWST (Centre for Affordable Water and Sanitation Technology)]

==References==