Food & WaterWater Purification
Making questionable water safe to drink — boiling, iodine, bleach and pool-shock dosing, plus what to do about radioactive particles.
CAUTION: If the water has a harmful chemical or radioactive material in it, adding a disinfectant will not make it drinkable - only special filtering can accomplish this.
General
- If water is cloudy, let it settle and filter with a clean cloth, towel, or paper coffee filter before purifying.
Boiling
- Bring water to a rolling boil for at least 1 minute. At altitudes above 6,500 feet, boil water for 3 minutes.
- Boiling is sufficient to kill pathogenic bacteria, viruses and protozoa.
- To improve the flat taste of boiled water, add one pinch of salt to each quart or liter of water, or pour the water from one clean container to another several times.
Iodine
- Add five drops of 2% tincture of iodine to each quart or liter of water that you are disinfecting. If the water is cloudy or colored, add 10 drops of iodine. Stir and let the water stand for at least 30 minutes before use.
- Iodine or tablets with iodine (tetraglycine hydroperiodlde) kill most germs, but not Cryptosporidium. It’s not recommended for continuous use - don’t use it for more than a few weeks at a time.
Bleach
| Water Volume | 5%-9% Sodium Hypochlorite |
|---|
| 1 quart/liter | 2 drops or 0.1ml |
| 1 gallon | 8 drop or 0.5ml |
| 5 gallons | 40 drops or 2.5ml or 0.5 teaspoon |
- Commercial bleach expires and is no longer effective for purifying water 6-12 months after opening the container.
- Use only regular, unscented chlorine bleach suitable for sanitization and disinfection according to the label.
- Do not used expired, scented, color safe or bleaches with added cleaners.
Calcium Hypochlorite (Pool Shock)
- Add one heaping teaspoon (approximately ¼ ounce) of high-test granular calcium hypochlorite (HTH) to two gallons of water and stir until the particles have dissolved. The mixture will produce a chlorine solution of approximately 500 milligrams per liter.
- To disinfect water, add one part of the chlorine solution to each 100 parts of water you are treating. This is about the same as adding 1 pint (16 ounces) of the chlorine solution to 12.5 gallons of water.
- If the chlorine taste is too strong, pour the water from one clean container to another and let It stand for a few hours before use.
Note: If water is cloudy, let it settle and filter with a clean cloth, towel, or paper coffee filter before purifying.
