13
• 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
