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INTERFERENCES
Interference may be caused by:
Chlorine
Iodine
Ozone
Oxidized forms of chromium and manganese
Alkalinity above 300 mg/L and acidity above 150 mg/L as CaCO
3
require neutralization since the color could instantly fade. To resolve
this, neutralize the sample with diluted HCl or NaOH.
In case of water with hardness greater than 500 mg/L CaCO
3
, shake
the sample for approximately 1 minute after adding the reagent.
Bromine
