Turbidity

Definition

A measure of the scattering of light by particles in water, reported in Nephelometric Turbidity Units (NTU).

A turbidity meter is fast, field-ready, and trends well over time, correlating roughly with TSS but influenced by particle size, shape, and color. Regular turbidity trending in cooling towers is often more useful than occasional TSS lab tests because trends reveal changes long before deposits are visible. Typical targets include below 25 NTU for a tower basin, below 5 post-filter and for closed loops, and below 1 for boiler feedwater.

Related concepts

Silt Density Index · Turbidity Trending · Suspended Solids

How it connects

• this measures Total Suspended Solids

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Part of The Blueprint of Water · 📏 measurement