Soil found on a carpet can be classified as spots and stains; surface litter (paper, thread, lint, etc); gritty unattached particles; and that which is adhering to the fibers.

Surface litter can be picked up with a vacuum. Although unsightly generally this material does not soil or ham the carpet. Most of the gritty unattached soil is tracked in on the feet; the longer it remains on the carpet, the more damage it will cause. Gritty soil will scratch and produce pits on fibers to dull them, making them appear even more soiled than they may be. It also produces a cutting action, which removes fibers and shortens the life of the carpet. Remove this soil by daily vacuuming of traffic areas and overall vacuuming at least once a week.

Soil which gives the carpet it dirty look is composed of sticky oils and greases containing tiny pieces of soil materials. By professional cleaning, this type of soil can be most thoroughly removed. The longer oily soil remains on the fiber, the more difficult it is to remove. Some oily type soils change chemically and produce a yellowish film on the fiber, which is impossible to remove. Other oils actually dissolve into some of the synthetic fibers, becoming part of the fibers themselves. These cannot be removed without damage to the fiber. For proper carpet maintenance, remove spots immediately, vacuum traffic areas daily, vacuum thoroughly once a week, and have a professional cleaning when traffic areas begin to show soil.