TM 10-4320-303-13
2.5.5.3 Determining Hypochlorite Solution Strength .
NOTE
Do not confuse the terms "dosage" and "residual."
Dosage refers to amount of chlorine added to the water.
Residual refers to amount of chlorine remaining in the waterafter 10 minutes.
a. Determine desired chlorine dosage or solution strength.
b. Check listing on table 2-19. Read across for required quantity of calcium hypochlorite powder needed.
c. If chlorine requirement is unknown, start with a 1.0 percent solution strength. Adjust in accordance
with chlorine residual tests.
NOTE
Table 2-19 is based on strength of calcium hypochlorite at 70% strength.
Table 2-14. Hypochlorite Solution Strength Index.'
Dosage
(ppm)
Solution (%)
Required Quantity of
Calcium Hypochlorite
(oz.)
0.25
0.05
0.50
0.50
0.10
1.00
0.75
0.20
2.00
1.00
0.25
2.50
1.50
0.375
3.75
2.00
0.475
4.75
2.50
0.60
6.00
3.00
0.725
7.25
3.50
0.825
8.25
4.00
0.95
9.50
5.00
1.00
10.00
10.00
2.50
25.00
15.00
3.50
35.00
20.00
4.75
47.50
25.00
6.00
60.00
* Figures in table 2-19 are based on the following:
(1) Model 1955-1: 100 gpm maximum flow rate through unit at 24 spm with 50 percent stroke
setting.
(2) Model A-506131: 100 gpm maximum flow rate through unit at 12 spm with 100 percent
stroke setting.
2-79
