Flush the faucets of the Lyster bag.
(5) Fill the plastic tube to a point just below the bottom of the yellow band
with water from the Lyster bag.
(6) Place the cap on the testing tube and shake the tube until the crushed
orthotolidine tablet is completely dissolved.
(7) Compare the yellow shade of the water with the yellow shade of the
band on the tube. If the color of the water is the same shade or darker than the band,
the chlorine residual is equal to or greater than that printed on the tube. If a lighter color
or no color is formed, the water does not have a sufficient chlorine residual--additional
chlorination and testing are required.
h. Add Additional Calcium Hypochlorite, If Needed. If the test shows a
chlorine residual less than five ppm, make a solution using water and one calcium
hypochlorite ampule, add the solution to the water in the Lyster bag, stir, cover the bag,
wait 10 minutes, and repeat the test. Continue this process until the chlorine residual
meets or exceeds the five-ppm requirement.
i. Wait Twenty Minutes. When the test shows the chlorine residual to be at
least five ppm, wait an additional 20 minutes. This additional time is needed to ensure
that all of the disease-producing organisms have been killed.
j. Retest the Chlorine Residual. Test the chlorine residual again after the
additional 20 minutes have elapsed using the same procedures given in paragraph g
(1) If the chlorine residual is equal to or greater than five ppm, the water is
ready to drink.
(2) If the chlorine residual is less than five ppm, repeat the procedures listed
in paragraphs h, i, and j above.
2-10. DISINFECTING WATER IN OTHER LARGE CONTAINERS
The same general procedures described in paragraph 2-9 can also be used to
treat water in containers other than the Lyster bag, but a different amount of calcium
hypochlorite must be used.
a. Five-Gallon Can. For a five-gallon can of water, the initial solution should be
made with one-half of the contents of a calcium hypochlorite ampule. Additional small
amounts should be added if needed.
b. Fifty-Five-Gallon Drum. For a 55-gallon drum of water, four or five ampules
should be used to make the initial solution.