Hanna Instruments HI83300 - Page 66

66
CHLORINE, FREE ULTRA LOW RANGE
• Add one packet of HI95762‑0 Free Chlorine Reagent.
Replace the cap and shake gently for 20 seconds.
• Reinsert the cuvette into the instrument and close the lid.
• Press Timer and the display will show the countdown prior to the measurement or, alternatively,
wait for 1 minute and press Read. When the timer ends the meter will perform the reading. The
instrument displays the results in mg/L of chlorine (Cl
2
).
INTERFERENCES
Interference may be caused by:
Alkalinity: above 1,000 mg/L CaCO
3
if present as bicarbonate (HCO
3
sample pH < 8.3); above
25 mg/L CaCO
3
if present as carbonate (CO
3
2‑
, sample pH > 9.0). In both cases, it will not reliably
develop the full amount of color or it may rapidly fade (negative error). To resolve this, neutralize
the sample with diluted HCl.
Acidity: above 150 mg/L CaCO
3
. May not reliably develop the full amount of color or it may rapidly
fade (negative error). To resolve this, neutralize the sample with diluted NaOH.
Hardness: in case of water with hardness greater than 500 mg/L CaCO
3
, shake the sample for
approximately 2 minutes after adding the powder reagent.
Bromine (Br
2
), Chloride dioxide (ClO
2
), Iodine (I
2
), Oxidized Manganese and Chromium, Ozone
(O
3
): positive error.