Beginning on January 1, 2005, spray guns used to apply auto repair and refinishing coatings must be cleaned by one of the following methods:
an enclosed spray gun cleaning system
non-atomized discharge of VOC solvent into a paint waste container
disassembling and cleaning of the spray gun in a container
atomized spray into a paint waste container that is fitted with a device designed to capture atomized VOC solvent emissions
With any of the above methods, the gun cleaning equipment involved must be kept closed when not in use.
Enclosed gun cleaning equipment may be worth considering as you can save significantly on solvent and hazardous waste costs. Your local vendor should be able to help or check out the following link on the web to search for a vendor: