A solution of water and detergent is injected into the carpet under pressure. It is then immediately extracted together with soil and spots which have been loosened and suspended.
The carpet is cleaned by a rotary machine using a soft brush and a specially formulated neutral detergent. The brushing action is just enough to break the bond between soil and the carpet fiber, but gentle enough that it is less abrasive than a normal upright vacuum.
Cleaning food stains and cooking grease out of carpet requires more specialized shampoos than do ordinary soils. The difficult protein bonds developed in food stains must be broken quickly in order to allow the shampoo action to efficiently remove them. Carpet shampoo was specifically developed to attack protein bonds and quickly clean carpets soiled by food and cooking grease when using rotary foam carpet cleaning equipment.