Wikipedia
Wet cleaning (green cleansing) refers to methods of professional laundering that, in contrast to traditional dry cleaning, avoid the use of chemical solvents, the most common of which is tetrachloroethylene (commonly called perchloroethylene or "perc"). Environmental groups and the United States Environmental Protection Agency have indicated that such alternative "wet cleaning" methods are better for the environment than perc, and proponents of wet cleaning state that these methods can be used without shrinking or otherwise damaging garments that typically require dry cleaning.
Typically, wet cleaning involves the use of a gentle washing machine using water, biodegradable soaps and conditioners, and various types of pressing and re-shaping equipment that may be specialized for many different fabric and fiber types. The most important aspect of successful wet cleaning is experience and knowledge of different types of fabrics and proper ways to finish garments by operators.
According to the Environmental Protection Agency (EPA), wet cleaning is the most environmentally sensitive professional method of garment cleaning. It does not use hazardous chemicals, it does not generate hazardous waste, nor does the process create air pollution and it reduces the potential for water and soil contamination. The specialized detergents and conditioner used in the wet clean process are milder than home laundry products. All of the products are disposed of down the drain and easily handled by the local waste water treatment facility. For professional cleaners, wet-cleaning is argued to offer several advantages, such as lowered costs for start-up capital, supplies, equipment and hazardous waste disposal, as well as less reliance on skilled labor.
Tailors have generally recommended that garments be returned to them once a year for wet cleaning and dry-cleaned in between. These tailors are also careful to choose materials that will not be destroyed by water, even if they later sew in the usual "Dry Clean Only" label. Some clothing manufacturers may mislabel their clothing "Dry Clean Only", even though there is no "reasonable basis" for making the claim that the garment will be harmed if it is not dry cleaned.