You may have noticed it in your own home, or the home of a neighbor or friend – dark, dirty-looking lines in the carpet around the baseboards, under doors and on stairs.

What are they?  Can they be removed?  Will they come back?

The dark greyish or black discolorations that occur around the perimeter of rooms and in the doorways of some houses can sometimes be a source of embarrassment and frustration.  Our clients rely on us not only to clean their carpets but also to educate them about how to maintain their carpet.  Before we explain what those mysterious dark lines are, we’ll talk about what they are NOT.

Contrary to what you may think, these lines have absolutely nothing to do with accumulated dust from poor housekeeping.  It is not a defect in the carpet.  And although some believe it to be mold, it is not.  Even pest control companies have been wrongly accused of causing these unsightly lines with their treatments.  So, what IS it?  It’s called filtration soiling.

Although it can happen in any home, filtration soiling is most common in homes that have forced air HVAC (heating, ventilation and air conditioning) systems.  At certain locations in the carpet, air is being forced through the fibers by pressure and temperature differentials.  The carpet fibers act as a filter, trapping pollutants that are in the air.

Some of these pollutants are the product of combustion and contain carbon.  Common sources are automobile exhaust, industrial air pollution, tobacco smoke, and even natural gas or oil furnaces.  This carbon, combined with oily residues from cooking and other sources, adheres to the carpet with very powerful electrostatic and chemical bonds.

The particles themselves are extremely small and very difficult to remove.  The best course of action is prevention.  Here are a few tips to prevent gray or lack edges from appearing:

Make sure that any means of combustion in your home, including gas or oil heating systems, cooking appliances, and water heaters are operating properly.  Incomplete combustion caused by improperly functioning appliances contain higher levels of carbon.  This can cause rapid soiling.

For our snowbird friends, homes up north should have their heat exchangers, flues and chimneys checked by an HVAC professional for leaks or improper function.

If you like to burn candles, limit how often you use the heavily scented ones.  The oils used in these candles do not burn completely adding to the pollutants in the air and carbon distribution throughout the room, accelerating filtration soiling.

Install high-quality air filters in your heating and air system and make sure they are changed regularly.

Consider using air purifiers, especially if smokers are present in the home.  Tobacco smoke produces one of the most difficult residues to remove.

When using a fireplace or woodstove, ensure that there is adequate fresh air entry to create enough of an updraft for the fireplace.  Otherwise, some of the smoke may get into the air and contribute to soil filtration.  You may need to open a window a little.  Don’t turn on ceiling fans in areas where you have a fireplace burning.  Air currents will pull smoke and carbon into the living space where it is disbursed throughout the home.

A thoroughly exhaustive carpet cleaning will not remove filtration lines, and additional spotting agents and labor will be required to tackle this issue.  Although complete removal of the discoloration may not be possible, we can usually drastically improve the appearance.  Of course, prevention is always your best line of defense.

Tru-Clean Surface Care is a Certified Partner with the prestigious Institute of Inspection, Cleaning and Restoration Certification (IICRC) and the International Carpet & Rug Institute (CRI).  In addition, we are A+ Rated by the Better Business Bureau and a six-year-in-a-row-winner of the coveted Angie’s List Super Service Award.

If Tru-Clean Surface Care can ever be of service or should you have any questions concerning your carpet, tile or upholstery cleaning needs, please do not hesitate to visit us online at www.TruCleanSurfaceCare.com or call us any time at 239-541-4888.