Various refrigerant reclamation methods are in use to recover refrigerants for reuse. Fluorocarbons and their derivatives (perfluorinated compounds) are used as fluoropolymers, refrigerants, solvents, and anesthetics. They are used as flame retardants, fire extinguishants, refrigerants, propellants, solvents, and pharmaceuticals. These included Suva refrigerants and Dymel propellants. R-12 and R-114 refrigerants, carbon dioxide, carbon monoxide, and other gases. Many trihalomethanes find uses in industry as solvents or refrigerants. Refrigerants and hydrocarbons are two commonly used components. Hydrocarbons are seeing increasing use as refrigerants. With widespread electrification and safer refrigerants, mechanical refrigeration in the home became possible. Depletion of the ozone layer by chemical refrigerants stimulated a stratospheric cooling effect. As an alternative to conventional refrigerants, other gases, such as CO (R-744), have been proposed. CFC refrigerants in common but receding usage include R-11 and R-12. Carbon tetrachloride is still used to manufacture less destructive refrigerants. Common secondary fluids include water, air, refrigerants, or phase-change materials. It is commonly used when referring to any fluorocarbon refrigerants.