One of the safest methods to kill bacteria, parasites and other pathogens found in water is by boiling the fluid. While it may not destroy all chemical pollutants, it’s an excellent proven method of disinfection.
Bringing your water to a rolling boil after five minutes under the heat of fire can combat most organisms that can make you sick. Leaving the water on for a total of 10 minutes at a boil is even safer.
Purifying through the boiling method can be done over an open flame on the stove top, campfire or in a fireproof glass or metal container. If you’re in the wild, you can also heat rocks and place them into your water container.
However, make sure to use anything but river or quartz rocks, as they can explode when under high heat.