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METHOD PROCEDURES
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CHLORINE
, FREE
LIQUID REAGENT PROCEDURE
• To an empty cuvette add 3 drops of
HI93701A-F
Free Chlorine
Reagent A and 3 drops of
HI93701B-F
Free Chlorine Reagent B.
• Replace the plastic stopper and the cap.
Swirl gently to mix.
• Add 10 mL of unreacted sample (up to the mark). Replace
the plastic stopper and the cap. Shake gently.
• Insert the cuvette into the holder and close the lid.
• Press
Read
to start the reading. The instrument displays the results in
mg/L
of
chlorine (Cl
2
).
Note:
Free and Total Chlorine have to be measured separately with fresh sample following the
related procedure if both values are desired.
INTERFERENCES
Interference may be caused by:
• Bromine, Iodine, Oxidized forms of Chromium and Manganese, Ozone
• Hardness greater than 500 mg/L CaCO
3
, to remove the interference shake the sample for
approximately 2 minutes after adding the powder reagent
• Alkalinity greater than 250 mg/L CaCO
3
or acidity value greater than 150 mg/L CaCO
3
, the color
of the sample may develop only partially or rapidly fade, to remove the interference neutralize the
sample with diluted HCl or NaOH
×
3
×
3
10 mL