Methods of Purifying Rain Water

• One way to purify water involves boiling the liquid. SW Productions/Photodisc/Getty Images

  Drinkable, clean water ranks amongst the most precious and limited resources on the planet. Most of the water on Earth comes in the form of salt water, while much of the fresh water supply suffers from pollution such as acid rain. Fortunately, humans have devised methods to purify polluted rain water, including boiling, filtering and chemically treating water.

Boiling Water

• The most common and widely known method of purifying water, boiling water, requires only a heat-resistant container and a heat source such as a stove top burner or a camp fire. To successfully purify the water, the temperature of the water must get to 212 degree Fahrenheit, the boiling point. The water should also boil for at least one minute. Boiling will kill bacteria and parasites, but it will not remove pollutants such as heavy metals.

Water Filteration

• Many households use a water filtration system to purify their water. The market holds two types of fliters: membrane filters and depth filters. Depth filters, such as Brita or WaterWorks II, force water through a filter that includes carbon materials, trapping bacteria and other dangerous particles. Membrane filters use very thin sheets that have microscope pores, allowing water through but not dangerous particles and bacteria. Common membrane filters include PUR-Hiker portable water bottles.

Chlorine Treatments

• Another household way of purifying water includes introducing a small amount of liquid chlorine bleach to the water. Bleaches such as Purex or Clorox work, although they must be free of dyes and perfumes. Approximately three drops of liquid chlorine bleach safely purify one quart of water, according to the Washington State Department of Health. For a half gallon of water, the safe amount of bleach goes up to five drops. The amount continues to go up incrementally, such as 1/8 teaspoon for a gallon of water, 1/2 teaspoon for five gallons of water and one teaspoon for 10 gallons of water.

Iodine Treatment

• Iodine also offers purifying properties; however, it makes the water toxic to anyone who is allergic to iodine. The safest proportions of iodine to water include five drops of liquid iodine to a quart of clear water and 10 drops of to a quart of cloudy water. Iodine-treated water also has the capacity to cause problems for pregnant women, women over 50, anyone on lithium or people who have thyroid problems.