Hanna Instruments HI 83414 - Manual (Page 19)

19
ADDING REAGENT (COLORIMETRY only)
• Because the reagent quantity is set up to react with 10 mL of
sample, it is very important to fill the cuvette correctly. The
liquid in the cuvette forms a meniscus; the bottom of the meniscus
must be at the same level with as the 10 mL mark.
• To open the powder reagent pack:
a) use scissors to open the powder packet
b) push the edges of the packet to form a spout
c) pour the contents of the packet
• Do not let the reacted sample stand too long after reagent is added or accuracy will be lost.
• All the reaction times reported in this manual were recorded at 20 ºC (68 ºF). As a general rule
of thumb, they should be doubled at 10 ºC (50 ºF) and halved at 30 ºC (86 ºF).
• Insert the cuvette with the mark aligned with the mark on the instrument top.
• It is possible to take multiple readings in a row but it is recommended to take a new zero reading
for each sample and to use the same cuvette for zeroing and measurement.
• After the reading, it is important to discard the sample immediately, otherwise the glass might
become permanently stained.
Note: In order to maximize accuracy prior to a measurement, follow the validation procedure to
be sure that the instrument is properly calibrated. If necessary, calibrate the instrument.