Shaw, one of the largest carpet manufacturers in the USA, recommends the hot water extraction system. Research indicates that the hot water extraction system provides the best capability for cleaning. This system is commonly referred to as "steam cleaning," although no steam is actually generated. The process consists of spraying a solution of water and detergent into the carpet pile and recovering the water and soil with a powerful vacuum into a holding tank. This can be done from a truck-mounted unit outside the home with only the hose and wand brought inside.