Venting The Sample - wtw Turb 555 Operating Manual

Turb 555 / Turb 555 IR
Avoiding or remov-
ing air bubbles
ba41113e07 04/2009

4.1.2 Venting the sample

Air bubbles in the sample affect the measuring result to a
massive extent because they have a large scattering effect
on the incident light. Larger air bubbles cause sudden
changes in the measured values whereas smaller air bub-
bles are recorded by the instrument as turbidity. Therefore,
avoid or remove air bubbles:
During sampling, ensure all movement is kept to a mini-
mum
If necessary, vent the sample (ultrasonic baths, heating or
adding a surface-active substance to reduce the surface
tension)
Use a pour-through vessel.
Operation
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