Re: Purifying water with clorox?
Amick Robert (amick@SPOT.COLORADO.EDU)
Thu, 10 Apr 1997 15:20:16 -0600
On Thu, 10 Apr 1997, Cheryl Singhal wrote:
> > >This is a question that someone told me boyscouts would be able to
> > We are taking a trip to central america soon and were wondering if you had
> > the formula for purifying water with a clorox solution
Previous posts suggesting water filters seem to be the best overall
solution when traveling/backpacking. The Backpacker magazine article on
water purification previously mentioned
probably has the best and most current information.
Be aware that some folks may be sensitive to iodine or chlorine, although
this is rare. Overall Chlorine seems to work the best, and is probably
more readily available than iodine, since it is the primary ingredient in
household bleach (sodium hypochlorite) but as previously noted, neither
chlorine nor iodine effectively kill parasites such as giardia. Only
boiling or filters are absolutely effective.
Attached are some tips from the Disaster
Preparedness Section of the Federal Emergency Management Agency Web page
(Please note that some of the information concerning water treatment for
"radioactive fallout" is not germane to typical applications, but was
included since the thrust of their article is on disaster preparedness):
Bob Amick, EMT-B, Explorer Advisor, High Adventure Explorer Post 72,
Boulder, CO/ American Red Cross Community Disaster Education Instructor
Three Easy Ways to Purify Water
In addition to having a bad odor and taste, contaminated
water can contain microorganisms that cause diseases such as dysentery,
cholera, typhoid and hepatitis. You should therefore
purify all water of uncertain purity before using it for
drinking, food preparation or hygiene (including brushing teeth, etc.).
There are many ways to purify water. None are perfect. Often
the best solution is a combination of methods. Before purifying, let any
particles settle to the bottom,or strain them through layers of paper towel
or clean cloth.
(editor's note: double coffee maker filters work well for this purpose
and save clogging of purification filters with large sediment)
Three easy purification methods are outlined below. These
measures will kill microbes but will not remove other contaminants such as
heavy metals, salts, most other chemicals and radioactive fallout.
(editor's note: saltwater can only be rendered fit for drinking by
distillation or reverse osmosis as noted below)
Boiling is the safest method of purifying water. Bring water
to a rolling boil for 10 minutes, keeping in mind that some water will
evaporate. Let the water cool before drinking.
Boiled water will taste better if you put oxygen back into
it by pouring it back and forth between two containers. This will also
improve the taste of stored water. (editor's note: be sure to avoid
cross-contamination: Never use a container which has held untreated water
to hold or process purified water unless the container has been cleaned
and sanitized first).
Chlorination uses liquid chlorine bleach to kill
microorganisms. (Before storing your water, treat it with a
preservative, such as chlorine bleach, to prevent
the growth of microorganisms. Use liquid bleach that
contains 5.25 percent sodium
hypochlorite and no soap. Some containers warn, "Not For Personal Use."
You can disregard these warnings if the label states sodium
hypochlorite is the only active ingredient
and if you use only the small quantities in these
Add two drops of bleach per quart of water (four drops if the water is
cloudy), stir and let stand for 30 minutes. If the water
does not taste and smell of chlorine at
that point, add another dose and let stand another 15
minutes. (editor's note: New information suggests that if it still does
not have a chlorine odor after the second treatment do not use it as it
cannot be safely purified, or revert to boiling the water as a failsafe.)
If you do not have a dropper, use a spoon and a square-ended
strip of paper or thin cloth about 1/4 inch by 2 inches. Put the strip in
the spoon with an end hanging down about 1/2
inch below the scoop of the spoon. Place bleach in the spoon
and carefully tip it. Drops the
size of those from a medicine dropper will drip off the end
of the strip.
Purification tablets release chlorine or iodine.
They are inexpensive and available at most
sporting goods stores and some drugstores. Follow the
package directions. Usually one tablet is enough for one quart of water.
Double the dose for cloudy water. (editor's note: allow more time if the
water is very cold for the chemical reaction to occur)
More Rigorous Purification Methods
While the three methods described above will remove only
microbes from water, the following two purification methods will remove
Distillation will remove microbes, heavy metals, salts, most other
chemicals, and radioactive dust and dirt, called radioactive fallout.
Filtering will also remove radioactive fallout. (Water itself cannot
become radioactive, but it can be contaminated by
radioactive fallout. It is unsafe to drink water that contains radioactive
Distillation involves boiling water and then collecting the
vapor that condenses back to water. The condensed vapor will not include
salt and other
impurities. To distill, fill a pot halfway with water. Tie a cup to the
handle on the pot's lid so that the cup will hang
right-side-up when the lid is upside-down (make sure the cup
is not dangling into the water) and boil the water for 20 minutes. The
water that drips from the lid into the cup is distilled.
To make a fallout filter, punch holes in the bottom of a
large bucket, and put a layer of gravel in the bucket about 1-1/2 inches
high. Cover the gravel with a towel cut in a circle
slightly larger than the bucket. Cover soil with a towel,
place the filter over a large
container, and pour contaminated water through. Then,
disinfect the filtered water using one
of the methods described above. Change the soil in your
filter after every 50 quart
Special thanks to the U.S. Department of Agriculture and the
American Red Cross
for reviewing this publication.
FEMA-215 March 1992
Updated: October 1996
Terry Howerton Sakima Group, Inc. SCOUTER Magazine Kansas City