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During · 2 min read

Make water safe to drink

How to boil or disinfect water when tap water may be unsafe, and what boiling cannot fix.

Draft: written from the official sources below, awaiting human review.

Best option: stored or bottled water

Use your stored or bottled water first. See your country page for how much your government recommends keeping.

If the water is cloudy

First filter it through a clean cloth, paper towel or coffee filter, or let it settle and pour off the clear water. Then boil or disinfect it.

Boil it (best)

  1. Bring the water to a rolling boil for 1 minute. Above 2,000 m (6,500 ft), boil for 3 minutes.
  2. Let it cool, then store it in clean, covered containers.

No way to boil? Use unscented household bleach

Check the label for the strength (sodium hypochlorite):

Bleach strength Per 1 US gallon (3.8 L)
5% to 9% 8 drops (about ½ mL)
1% 40 drops (about 2½ mL)
  • Double the amount if the water is cloudy, coloured or very cold.
  • Stir well and wait at least 30 minutes before drinking.
  • Use only plain, unscented household bleach.

What boiling and bleach cannot fix

If the water may contain fuel or toxic chemicals, boiling or bleach will not make it safe. Use bottled water or another source and follow your local health authority.

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