Preparation Of Dilutions From The 4000 Ntu Formazin Stock Solution; Measurement Techniques; Degassing - Removal Of Bubbles - Lovibond TB 300 IR Mode D'emploi

2.3.7.3 Preparation of dilutions from the 4000 NTU Formazin
Stock Solution
To prepare the dilutions from a 4000 NTU Formazin Stock Solution and dilution water:
Standard
20 NTU
200 NTU
800 NTU
Use class A volume pipette and glass flasks.
Use dilution water for the < 0.1 NTU standard.

2.3.8 Measurement techniques

2.3.8.1 Degassing – Removal of Bubbles
Note: Do not use with T-Cal Standards
If the Turbidity is low it is important to remove air bubbles from the sample, using one or a
combination of the following methods:
• Addition of a surfactant
• Application of a partial vacuum
• Application of heat
• Use of an ultrasonic bath
Note:
This procedure can influence the nature of the sample and therefore the turbidity reading.
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Step 1
Add 100 ml of Pipette 1.00 ml well
dilution water to
a clean 200 ml
volumetric flask.
Add 50 ml of Pipette 5.00 ml well
dilution water to
a clean 100 ml
volumetric flask.
Add 50 ml of
dilution water to
a clean 100 ml NTU Formazin Stock
volumetric flask.
Step 2
mixed 4000 NTU
Formazin Stock
Solution to this
200 ml flask.
mixed 4000 NTU
Formazin Stock
Solution to this
100 ml flask.
Pipette 20.00 ml
well mixed 4000
Solution to this
100 ml flask.
Step 3
Fill to the mark
with dilution water.
Close and mix the
flask.
Fill to the mark
with dilution water.
Close and mix the
flask.
Fill to the mark
with dilution water.
Close and mix the
flask.
TB300 IR 6 03/2022