As a matter of fact, when the total suspended solids are mentioned, the total amount of solids that can and does not precipitate in the water sample is expressed. These collapsible and non-collapsible solids cause physical contamination of the water after exceeding a certain amount.

Filtered and unfiltered samples are used to detect dissolved and undissolved solids. Solids dissolved in water generally consist of organic substances and inorganic salts. They are suspended or colloidal in water. Some solutions are considered to be a homogeneous solution, but with a very sensitive microscope, they are heterogeneous. These kinds of solutions are called colloidal solutions.

There are two kinds of undissolved solids. They are thin, suspended solids, some of which cannot be precipitated. Some of them are collapsible with their own weight. Briefly, solid materials that are heavier than water with gravity force settle to the bottom. Measurements of solids that can precipitate in wastewaters determine the volume of precipitation unit needed.

Suspended solids are considered as settable solids when controlling the pollution of rivers. These substances precipitate over time, causing biological and chemical deposits.

Among the physical analyzes carried out within the scope of food analyzes are the determination of collapsible solids. These analyzes are performed in laboratories that are authorized by local and foreign accreditation institutions.

These laboratories perform these analyzes in accordance with generally accepted test methods and test criteria. It also follows scientific research. The determination of settable solids is based on the following standard:

• SM 2540 F Detectable solids

This standard is intended for the determination of the amount of suspended solids present in domestic and industrial wastewater, surface waters and saline waters.