Cleaning chemicals are used to clean, degrease, disinfect, and sanitize surfaces. Degreasers clean floors, machines, parts, and tools by removing water-insoluble contaminants. Surface disinfectants and sanitizers limit the number of germs on clean surfaces and prevent them from spreading. Concentrated chemicals are diluted and mixed using dilution control systems. Stains and mineral deposits are removed with calcium, rust, and lime removers. Mold, mildew, adhesives, graffiti, furniture, carpets, hard floors, metal and stone, and pools and spas can all be treated with specialized cleaning solutions.