Nephelometric Technology

A nephelometer is an instrument for measuring the concentration of suspended particulates in a liquid or gas colloid.

Nephelometer measures suspended particulates by employing a light beam (source beam) and a light detector set to one side (often 90°) of the source beam. Particle density is then a function of the light reflected into the detector from the particles.

To some extent, how much light reflects for a given density of particles is dependent upon properties of the particles such as their shape, color, and reflectivity.

Nephelometers are calibrated to a known particulate, then use environmental factors (k-factors) to compensate lighter or darker colored dusts accordingly.

K-factor is determined by the user by running the nephelometer next to an air sampling pump and comparing results. There is a wide variety of research-grade nephelometers on the market as well as open source varieties.