Dark, shadowy, dirty lines on the carpet along baseboards, under doors and draperies, along the edges and in the crevices of carpeted stairs are visible signs of a problem called filtration soil. With the right tools and information, you can clean the dirty edges of the carpet. But first, it’s important to know what that dirt is and how it got there.
Basically, your carpet is the biggest filter in your home. Just like your furnace and air conditioning filter that filters out airborne soils that pass through it, your carpet does the same thing. Filtration soil is an accumulation of soot from dirty ducts, smoke from candles, the fireplace or tobacco, kitchen grease from the oven and cooktop, smog, auto emissions, and pollutants from outdoors.
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