Boiling Water
Bringing water to a rolling boil to inactivate pathogens — the oldest household treatment.
What is it?
Boiling heats water to a rolling boil (one minute, longer at altitude), reliably killing bacteria, viruses, and protozoa.
Why does it matter?
It is the most universally understood method and works against essentially all waterborne pathogens, serving as a benchmark for other treatments.
How does it work?
Sustained high temperature denatures the proteins and nucleic acids pathogens need to survive, inactivating them regardless of type.
Who benefits?
Any household with access to fuel, and anyone under a boil-water advisory during a supply failure.
Who may be disadvantaged?
Households paying for scarce fuel bear a real cost and health burden; indoor combustion adds smoke exposure, and the poorest are hit hardest.
What evidence exists?
The microbiology of thermal inactivation is well established; the practical constraint is fuel cost and consistent practice, not efficacy.
What tradeoffs exist?
Highly effective but fuel-intensive, time-consuming, adds indoor air pollution, and leaves no residual protection against recontamination.
Common misconceptions
Water does not need to boil for ten minutes — reaching a rolling boil is sufficient. Boiling does not remove chemical contaminants or sediment.
What you can do next
Compare the fuel and health costs of boiling with SODIS, chlorination, and filtration for your setting.