14
• It is important that the sample does not contain any debris.
This would corrupt the reading.
• In order to avoid reagent leaking and to obtain more
accurate measurements, it is recommended to close the
cuvette first with the supplied HPDE plastic stopper and
then with the black cap.
• Each time the cuvette is used, the cap must be tightened
to the same degree.
• Whenever the cuvette is placed into the measurement cell,
it must be dry outside, and completely free of fingerprints,
oil or dirt. Wipe it thoroughly with
HI731318
or a lint‑free
cloth prior to insertion.
• Shaking the cuvette can generate bubbles in the sample, causing higher readings. To obtain
accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette.
• Do not let the reacted sample stand too long after reagent is added, or accuracy will be lost.
• 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 immediately the sample, otherwise the glass might
become permanently stained.
• All the reaction times reported in this manual are referred to 25 °C (77 °F). In general, the
reaction time should be increased for temperatures lower than 20 °C (86 °F), and decreased
for temperatures higher than 25 °C (77 °F).
• 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.
GENERAL TIPS FOR AN ACCURA
TE MEASUREMENT
