It is thanks to nephelometers, which are instruments that measure the light scattered at right angles to the incident light. These instruments can therefore identify the amount of light that can pass through any substance.
Why are we talking about them?
In the water treatment sector, nephelometry is used to categorize turbid waters. Nephelometric Turbidity Units or NTUs are used to define the turbidity level of a water sample.
- Briefly, the turbidity of water expresses its concentration of suspended matter. To learn more about this topic, see this article: What is water turbidity?
Explained in a different way, the level of turbidity affects the clarity of the solution. This means that the more turbid a sample is, the more suspended solids it contains. When a nephelometric instrument performs its calculation, the suspended matter blocks the light passing through the sample. This is the principle behind the identification of the nephelometric turbidity unit of a sample.