FILTRATION SOIL & CARPET CLEANING
If you have light colored carpet, you may have experienced dark lines that appear mostly around the edge of the room, under doorways, under the skirting of furniture, and on stairs. Its makeup is oily and the molecules of the soils are so small that cleaning them or removing them from fibers is very difficult. In addition, they have an electrical "charge" that bonds them firmly to the fiber. This soiling is called filtration soiling because it comes from air passing through the carpet as it attempts to get through the crack between the carpet and baseboard or under a closed door.
More often than not these filtration lines can not be cleaned with your standard home cleaning machine or even with the standard truck mount cleaning process. In order for a carpet cleaner to get these lines out he (or she) will have to get on their hands and knees with special chemicals to remove the filtration lines. It is probably the most difficult task to ask a carpet cleaner to perform. That is why most cleaners will not attempt to clean these filtration lines, and they will tell you there is no hope. With the proper cleaning technique, chemicals, and patient these filtration lines can be removed. Be prepared to pay more this type of service because it does require more time and expense on behalf of the cleaner.
To help prevent filtration soiling vacuum and wipe the edges of the carpeting on a weekly basis. The best type of vacuum is a HEPA filtration, it will trap these fine particles in the bag. Be careful around the tackstrip on the edge of the carpeting, it could nick your fingers!