Environmental engineering has a leading role in the elimination of ecological threats, and can deal with a wide range of technical and technological problems due to its interdisciplinary character. It uses the knowledge of the basic sciences - biology, chemistry, biochemistry and physics - to neutralize pollution in all the elements of the environment, i.e. the hydrosphere, atmosphere and lithosphere. Mainly, environmental engineering deals with the design and maintenance of systems of water supply, sewage disposal, heating, ventilation and air-conditioning in buildings. In brief, it deals with securing technically, the conditions which create a safe environment for mankind to live in.