What components are included in total suspended solids?

Total suspended solids (TSS) refer specifically to the solid material in water that is not dissolved and remains in suspension. This can include a variety of particles, such as silt, organic matter, and microorganisms. The two primary components that make up total suspended solids are settleable solids and suspended solids.

Settleable solids are those that can sink to the bottom of a container when allowed to stand. These solids are included in the total suspended solids measurement as they are still part of the overall solid content in the water before they settle.

Suspended solids, on the other hand, are particles that are not heavy enough to settle quickly under the influence of gravity and remain in suspension. They are critical in assessing the quality of wastewater and its treatment process.

Dissolved solids, while important in water quality assessments, do not qualify as part of the total suspended solids count, as they are particles that are completely dissolved in the water and do not have a weight that can be measured as part of the suspended content.

Thus, the inclusion of settleable and suspended solids directly correlates with the definition of total suspended solids, making it the correct choice.