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Boiling Warer


If the water supply is contaminated, or if you are under a Boil Water Advisory, all water to be used for drinking, hand washing, washing fruits and vegetables, dish washing, or cooking, must purified (e.g. disinfected or sanitized).

One of the most common methods for purifying water is boiling.  If procedures for boiling water are correctly followed, unwanted infectious bacteria or other biological contaminants will be adequately removed.  However, if the water is contaminated with hazardous chemicals, this method will not purify the water.

The water should be brought to a rolling boil.  Using a lid, will reduce water evaporation.  The water should be brought to a “rolling boil” for at least one minute.  Allow the water to cool before dispensing into a clean, sanitized, tightly capped container.  Cloudy water should be boiled (rolling) longer: three to five minutes.

Rolling Boil is a term that describes one of the stages encountered when boiling a pot or kettle of liquid (e.g. water).  When being boiled, water will reach a stage where it has started to produce bubbles that make it look like it is boiling, but if you stir it, the bubbles briefly go away, making the water appear to stop boiling. The term “Rolling Boil” describes a stage a few minutes past that, when so many bubbles are being produced so fast from the bottom of the pot, that stirring won’t impact their production. The bubbles get to be very large. They rocket up from the bottom of the pot, breaking the surface and while rising and breaking they vigorously move about the liquid that is being boiled.