What is the ratio of bleach to water to use for emergency purification of water?

Emergency water purification uses one-eighth of a teaspoon of bleach for every gallon of water. Allow water purified with bleach to stand for 30 minutes prior to use.

Bleach does not remove sediment from drinking water. Cloudy water should be filtered through a cloth filter prior to being treated with bleach. When filters are unavailable, allow the sediment to settle and move the clean water to another container.

Drinking bottled water and boiling drinking water are both preferable options to using bleach for water purification. Bleach is only the recommended method of emergency water purification when no alternate water source is available and contaminated water cannot be boiled for one minute.