In order to understand how to clean carpet, we need to know what soil is and the problems it presents. Soil in carpet is any substance that is foreign to the carpet's construction. Soil includes substances such as dirt, sand, food, oil, hair, dust, and anything else that finds its way onto carpet. Carpet not only traps soils that fall onto it, but it also acts as a filter for the environment. Dust, dander, soot, gases and odors are all trapped in carpet.



Most soil found in carpet is sand and dirt tracked in by foot traffic. This type of soil is abrasive to the carpet and is what causes the carpet to wear. The gritty matter actually cuts and scratches the fibers of the carpet, resulting in a dull, worn appearance. The rest of the soil found in the carpet is usually grease and oils. This type of soil is acidic, which is why most carpet cleaning chemicals are alkaline cleaners. Alkaline cleaners neutralize the acids in order to remove the grease and oils.

Soil and dirt are considered "soluble" whereas oil, grease and solids are considered "insoluble", which means they can't be dissolved in water or solvents. Because soil and dirt are soluble, they are more easily removed with vacuuming and extraction. However it's the insoluble matter that professional carpet cleaners are more concerned about.

One of the problems inexperienced carpet cleaners have is leaving residue in carpet. This is one of the main reasons they're often called back to the job -- residue causes rapid re-soiling, prompting phone calls from unhappy customers.

What about "apparent" soil? Apparent soil isn't actually soil at all. It's simply the worn appearance of the carpet that makes it seem like it's dirty. Busy hallways often have wear patterns and scratches in the fibers that simply can't be restored with cleaning. When carpet cleaning contractors see carpets with these conditions, it's best to explain it to the customer before work begins so they understand that you won't be able to repair the wear patterns.

Following are the steps needed to remove soil from carpet:

1. Remove the dry soil, sand and solids by vacuuming.

2. Suspend the soil. This means separating the soil from the carpet so it can be removed. There are 4 keys to soil suspension: temperature, agitation, chemical action, and time. If one of these four are missing or decreased, then you need to compensate for it by increasing one of the other three. For example, if you don't have enough heated water, then you can compensate with additional agitation.

3. Soil removal (extraction). This is accomplished by rinsing (steam cleaning or hot water extraction method), absorption (spin bonneting), or after-drying (dry powders that are vacuumed up).

4. Rake the carpet so that wand marks or swirl marks are removed.

5. The last step is drying the carpet. This needs to happen as quickly as possible in order to avoid problems such as re-soiling, mildew and odor. The fastest way to dry carpet is with fans or air movers. Understanding soil and what it takes to remove it properly from carpet is the first step to providing carpet cleaning services in your business. And when removed properly, results in satisfied customers.