What instrument is typically used to measure turbidity?

A turbidimeter is specifically designed to measure turbidity in water, which is an important aspect of water quality assessment. Turbidity refers to the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The turbidimeter works by shining a light through the water sample and measuring the amount of light scattered by particles suspended in the water. This reading is then converted into a turbidity value, typically expressed in NTU (Nephelometric Turbidity Units).

While other instruments, such as a spectrophotometer, can analyze various properties of light absorption and can be used in some turbidity assessments, they are not solely dedicated to measuring turbidity. A filtration unit is utilized for removing particulate matter from water, but it does not measure turbidity directly. A water analyzer may perform multiple tests, but again, it does not focus exclusively on turbidity measurement as a turbidimeter does. Thus, the turbidimeter is the most appropriate and specialized instrument for directly measuring turbidity levels in water.