 Pretreatments similar to those in dry-cleaning and "very low moisture" systems are employed, but require a longer dwell time of 15 to 20 minutes, because of lower amounts of carpet agitation. Ideal pretreatments should rinse easily and leave dry, powdery, or crystalline residue that can be flushed without contributing to re-soiling .
<meaning-changed>  Pretreatments similar to those in dry-cleaning and "very low moisture" systems are employed, but require a longer dwell time of 15 to 20 minutes, because of lower amounts of carpet agitation. Ideal pretreatments should rinse easily and leave dry, powdery, or crystalline residue that can be flushed without contributing to re-soiling .
 using more fluid). Drying time may also be decreased by fans, de-humidifiers or simply opening windows .