Measurement Of High Turbidity Values; Measurement Of Low Turbidity Values - VWR TIR 200 Manual De Instrucciones

Measurement of high turbidity values

High turbidity samples with more than 1100 NTU ("overrange") may be diluted. The dilution
water should be a water with very low turbidity as described in chapter "Preparing dilution
water".
For accurate dilution proceed as follows:
Mix the water sample well and pipette x ml of the water sample (see table below) into
a 100 ml volumetric flask. Fill with low turbidity water up to the mark and mix gently.
Water sample
(x ml)
10
25
50
Fill the diluted water sample into the vial, perform reading and multiply the displayed result
with the multiplication factor.
Note:
The dilution of the water sample may alter the characteristics of the suspended
particles and produce erroneous results.

Measurement of low turbidity values

Accurate and repeatable measurements of low turbidity values depend on exact measure-
ment techniques.
• Use a clean, unscratched and indexed vial.
• Rinse the vial three times with the sample.
• Add the water sample to the mark.
• Allow the vial to stand for 1 -5 minutes so that bubbles can disappear.
• Carefully invert the vial (so that settled particles disperse in the sample).
• Place the vial in the sample chamber and press the Read key.
• Perform multiple measurements, until a reproducible value is displayed (leave the vial in
the sample chamber).
Note the smallest consistent and reproducible value.
VWR ver 1 01/2018
Multiplication factor
10
4
2
21