At what angle is light measured in a turbidimeter?

In a turbidimeter, light is typically measured at a 90-degree angle from the incident light beam. This angle is significant because it allows for the optimal measurement of light scattering caused by suspended particles in the water sample. The turbidity of the sample causes light to scatter, and measuring at a right angle enables the detection of this scattered light, which directly correlates with the concentration of turbidity present.

Measuring at 90 degrees ensures that the influence of the incident light is minimized in the readings, providing a more accurate representation of the turbidity levels. This critical measurement technique helps analysts assess water quality effectively and is essential in compliance with various environmental standards.