A mechanical bar screen's main job is to catch and remove bigger solids, keeping them out of the wastewater treatment process where they may clog things up. The screen is made up of a number of parallel bars or racks with variously sized gaps between them. These bars are close together enough to allow bigger solid items to pass through while yet trapping them. Mechanical bar screens avoid jams and obstructions in downstream pipelines, pumps, and treatment equipment by eliminating bigger solid contaminants. They assist in limiting the entry of garbage, plastics, and other contaminants that threaten aquatic environments.