What are Nephelometric Turbidity Units (NTU) used to measure?

Nephelometric Turbidity Units (NTU) are specifically used to measure the amount of light scattering caused by suspended particles in water. This measurement is critical in assessing the clarity or turbidity of water, which can impact both aesthetic qualities and the effectiveness of disinfection processes in potable water treatment.

When light passes through water, particles such as sediment, plankton, and other materials scatter the light. A higher NTU value indicates a greater concentration of these particles, which can affect water quality and treatment processes. Therefore, the assessment of turbidity using NTU is fundamental in both wastewater treatment operations and in ensuring the safety and clarity of potable water supplies, guiding necessary treatment measures.

In contrast, measuring the concentration of dissolved minerals, water temperature, or pH levels requires different methodologies and units, making those choices incorrect in this context.