DelAgua OXFAM-DELAGUA, Руководство пользователя

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OXFAM-DELAGUA Water Testing Kit — Users Manual
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6.
Again, invert the comparator several times to dissolve the tablet (use the
plastic paddle if the tablet is slow to dissolve). Leave the colour to develop for
10 minutes. Read the total chlorine residual (mg/litre) by matching the colour
in the cells with the standard colour scale.
7.
Subtract the free chlorine result from the total chlorine result to obtain the
combined chlorine concentration:
Summary
Phenol Red = pH
DPD No 1 = Free chlorine residual
DPD No 1 plus DPD No 3 = Total chlorine residual
Total - Free chlorine = Combined chlorine
5.3 Turbidity Analysis
Note: The turbidity tube covers the range 5 to 2,000 TU
1.
Carefully remove the 2 halves of the
turbidity tube from their clips in the
lid of the case. Push the upper tube
(open at both ends) squarely into the
lower tube and align the graduation
marks up the side. Look through the
open end of the tube at the black circle
printed on the yellow base of the tube;
this is the marker. Ensure that there is
good illumination available. Normal
daylight is adequate for this purpose.
Assemble the turbidity tube