Carpet Cleaning

There have been a number of surprising studies throughout the years regarding the amount of germs and bacteria that can be found on office desks, cell phones, and the sponges we use to wipe down counters and wash dishes. However, one study that has gotten relatively little notice relates to carpets and concerns about indoor air quality (IAQ).

In that study, which was conducted by the University of Arizona several years ago, researchers asked a group of people to wear brand-new shoes for two weeks. They were to wear the shoes everywhere—to school, to work, shopping, etc. After two weeks, the shoes were returned to be tested for contaminants that might have collected on the shoe bottoms. What researchers discovered surpassed their expectations:

  • The shoes collected more than 420,000 units of bacteria, and all the shoes had varying amounts of bacteria on them.
  • Potentially hazardous levels of E. coli were present on about one-third of the shoes.
  • Greywater, food, drinks, grease, tar, and dust were found on all of the shoes to varying degrees.


These kinds of contaminants and bacteria all have the potential to negatively impact indoor air quality when they are walked into a facility on users’ shoes. However, in most cases, carpets act as an environmental filter, trapping soils, bacteria, and contaminants and stopping them from becoming airborne, which means healthier IAQ for everyone.

But the effectiveness of carpeting as an environmental filter is dependent on maintenance. Carpets must be properly cleaned and maintained at regular intervals in order to protect IAQ. And this typically begins with the creation of an effective and sustainable carpet maintenance program.1

Creating a Carpet Maintenance Program

According to Doug Heiferman, a textile specialist and trainer with The Institute of Inspection, Cleaning, and Restoration Certification (IICRC), the first step toward creating an effective, sustainable carpet maintenance program should be training and certifying the technicians in charge of carpet cleaning. “Certification cannot be stressed enough,” notes Heiferman. “(Cleaners and technicians) must possess the knowledge to properly maintain carpets as a first line of defense to foster good IAQ.”

Another step that must be taken before creating an effective carpet maintenance program is to study the amount of foot traffic and the number of people who generally use each carpeted area. This information will help determine the “soil rating” of the facility, which is the measure of the intensity of the soil load that can accumulate in the carpets. These ratings are designated as light, normal, moderate, heavy, or extreme. Soil ratings help determine the frequency of tasks such as vacuuming, interim carpet cleaning, and hot-water carpet extraction.

For instance, a facility with a moderate soil rating should be vacuumed two to four times per week to remove dust, contaminants, and particulates from carpets. Additionally:

  • Spotting should be performed daily or as soon as spots are noticed.
  • Heavy traffic areas should be cleaned using either interim or restorative carpet cleaning methods every six months.
  • All carpets should be cleaned using hot-water carpet extraction at least once per year.


Unfortunately, determining the soil rating of a facility and how frequently carpet cleaning tasks should be performed to help protect IAQ can be determined only on a case-by-case basis. “Facilities vary in traffic, soiling rates, and usage,” explains Heiferman. “Additionally, climate and the desired appearance level of the carpet are considerations that must be evaluated in order to build an effective maintenance program.”

Controlling Soil Ratings

While the soil ratings for a facility must be determined on an individual basis, there are steps all facilities can take to help control their soil levels—and it all begins outside the facility. Parking lots and walkways should be cleaned and maintained regularly to help prevent dust and contaminants from entering the facility and damaging IAQ.

According to JoAnne Boston of Crown Mats and Matting, high-performance matting systems play a crucial role in keeping indoor facilities and their air healthy. Far beyond a simple welcome mat on which visitors can wipe their feet, a true matting system involves three different types of mats, all performing specific duties:

  • Five feet of scraper matting placed outside the building entry. This is designed to scrape larger particulates and soils off the bottoms of shoes.
  • Five feet of scraper/wiper matting placed directly inside the doorway. This removes remaining larger soils and collects and traps moisture from shoe bottoms.
  • Finally, five feet of wiper matting placed inside the facility. “This is referred to as the final line of defense,” says Boston. “The wiper matting is designed to capture any remaining soil and moisture, preventing it from entering the facility.”

The Importance of Carpet Extraction in Protecting IAQ

Earlier we referenced the role of “interim” cleaning methods as part of an overall carpet maintenance program. Typically this refers to carpet cleaning methods that remove soils found on the top surfaces of the carpet. These include vacuuming as well as shampooing and bonnet cleaning methods. According to Mark Baxter, an engineer with U.S. Products, while these methods can be effective, the key thing to remember is that they are, as the name implies, only interim or short-term measures.

“Interim methods can only do so much. In order for carpets to serve as a filter and protect IAQ, they must be thoroughly cleaned using restorative methods.”

Baxter takes this a step further, advising that carpets should be cleaned using hot-water carpet extractors that heat the water or cleaning solution to more than 200°F. “[Heat] improves the effectiveness of cleaning chemicals so that less chemical may be necessary. This makes the entire carpet cleaning [process] greener and more sustainable and helps protect IAQ,” says Baxter.

The Mold Issue

The presence of moisture in carpets can foster microbial growth such as mold and mildew, which can have a definite negative impact on IAQ. Even conditions such as high humidity and stagnant air can create a welcome environment for mold growth in carpets. Fortunately, an effective carpet maintenance program can minimize or even eliminate this problem. To help prevent the growth of mold and mildew, cleaning programs should include regular inspections for water intrusion that can lead to mold growth.

Along with hot-water extractors, low-moisture extractors can help prevent the growth of mold resulting from restorative carpet cleaning. Low-moisture extractors typically release less water into carpets and have more powerful vacuum systems to extract moisture. The goal of low-moisture carpet cleaning is for the carpet to dry within approximately two hours (instead of the six or more hours it can take after using a conventional carpet extractor). This reduced drying time means that low-moisture extractor systems can significantly reduce the possibility of mold growth.

Unfortunately, many facilities both large and small do not have a carpet maintenance program in place. Yet having such a program is so important that many cleaning consultants recommend this information be put in writing to formalize it and ensure that all steps are implemented as scheduled.

“A program that addresses all of these cleaning and maintenance issues, beginning with the proper training of cleaning technicians, promotes sustainability and protects IAQ and the health of all building users,” says Baxter. “It also ensures that soils and contaminants are removed from carpets, which not only enhances their appearance but increases their longevity as well.”

Keeping your carpets clean and healthy, regular cleaning will extend the life of your carpets, saving you money in the long run.

Deep-seated grit and grime needs to be extracted from the base of your carpets pile to prevent “wear and tear”, as carpets wear from “the bottom up”.  A three monthly maintenance plan will double the life of your carpets.

Corporate Companies enjoy special discounts.

Tiny little dust mites, which are so small they can only be seen under a microscope, are the cause of extreme discomfort.  They cause allergies with are not pleasant for staff members.