Containers for screenings are made in a way that allows the storage of extremely hazardous materials to the environment. The name of this waste comes from the unusual bars, which are retained. Composition of screenings depends on the source of sewage. They are larger and smaller components and relatively large particles, which may be a typical component of a particular type of treatment plant, however, they can also come from leaks and other incidents the sewage system, and the improper use of such a system (for example,. through the illegal connection to him, the sender plant with other parameters than those provided for a given system).