Chematest 30
General Information
A-96.730.101 / 151118
5
2.
General Information
2.1. Basic Rules for Determinations
The precision and repeatability of a determination depends greatly
on the operator's technique. Please observe the following rules:
Always use clean utensils
Residues from previous measurements can falsify the results. All
utensils such as syringes, cuvettes or similar must be rinsed with
clean water after each measurement. Fill the cuvette with the sam
-
ple 2 to 3 times before each measurement.
Position cuvettes correctly
Cuvettes must always be positioned in the same way. Keep the cu
-
vette free of fingerprints and dry the outside of the cuvette before
inserting it into the cuvette adapter.
Wipe off condensation
If condensation occurs on the cuvette (cold sample in a warm envi
-
ronment), wipe it off and carry out the measurement as quickly as
possible.
Observe proper sampling
Take the water samples about 10 cm below the water surface and
about 50 cm from the edge of the pool. Allow as little time as possi
-
ble to elapse between taking the sample and making the measure
-
ment.
Observe proper dosing and mixing
Use the 10 ml syringe for exact dosing of the sample. Rinse the sy
-
ringe several times with the sample. When filling the syringe, make
sure that there are no air bubbles and that the volume is 10 ml.
The order in which sample and reagents are added to the cuvette
varies from method to method. If the reagents are added to the cu
-
vette after the sample, special care must be taken to ensure that
the sample and the reagents mix well. For this purpose, carefully
turn the closed cuvette over, but do not shake it.
