Carpet for Cleaner Air

By Lynne B. Peer

Maintaining good indoor air quality in the home and workplace is an important step in encouraging good health and reducing allergens. Because we spend 90 percent of our time indoors, we must do everything possible to improve the quality of the air we breathe.

What affects our indoor air quality? Interior building materials like wood, particle board and laminates, furniture and wall coverings, people and pets, cleaning substances, the condition of heating and air conditioning, life activities like smoking and cooking, dust and dust mites, and of course the outdoor air. Interior finishes and building materials have the potential to affect indoor air quality because they emit volatile organic compounds (VOCs). Scientific studies have shown that new carpet is one of the lowest emitters of VOCs into the indoor environment, and these emissions dissipate very quickly -- within 48 to 72 hours after installation with good ventilation.

Carpet's holding characteristics actually make it a floor covering of choice for allergy sufferers. House dust, pollen and dust mites are a constant challenge in the home. They are found in the highest concentration in mattresses and bedding. The key in preventing reactions to these pollutants is to keep the allergen particles from getting into the breathing zone. Gravity causes airborne particles to fall to the floor and the benefit of a carpeted floor is that the dust, dirt and particles are retained in the carpet until they can be removed by vacuuming. It is the airborne particles that affect those sensitive individuals, not the particles that are held in the carpet. Therefore, the holding characteristics of carpet, as compared to a smooth surface floor, keep particles from circulating around in the room due to foot traffic and airflow.

Vacuuming is the single most effective and economical means of keeping floor coverings clean and removing dust and allergens from the indoor environment. It has been proven that 90 percent to 95 percent of all dry soil by weight can be removed from carpet by routine vacuuming. In addition to vacuuming, keeping the humidity low (below 55 percent) and using heating, air conditioning and possibly a dehumidifier is important. In an office environment, dust, pollen, skin particles and other office material particles circulate in the air and must also be removed by routine maintenance and effective ventilation.

The key, however, to removing the particles collected in the carpet is to vacuum routinely with a high quality vacuum cleaner that has adjustable brushes and bears the Carpet and Rug Institute's Green Label. Those commercial and residential vacuum cleaners have passed stringent tests in three areas: soil removal, containing the dust within the filter bag and maintaining the carpet's appearance. As noted in Architectural Review Magazine, "... the fact that carpet may hold more lint and dust than a smooth surface may be considered an advantage as it is better to have dust particles held down in the carpet until it is vacuumed, than to have it stirred up and airborne by continual shuffling of shoes -- as is the case with smooth surfaces."

According to many allergists, the real cure for sniffing, sneezing and wheezing may be as simple as consistent, regular house cleaning. Common household allergens such as dust, dust mites, mold, pet dander and cockroach allergen can trigger allergies. Dr. Mary Lasley, a pediatric allergist, explains, "Simple changes in your routine house cleaning can reduce allergies and help your family live more comfortably. Removing dust and soil often from all surfaces is a key element in maintaining good indoor air quality." It has been recommended that carpet be vacuumed once a week for every person and large pet that lives in the home. Commercial recommendations are based on the number of foot traffics and individuals who occupy the offices.

In response to some individuals who worried that their carpet might be the cause of allergic reactions, comparison data from a 10-year study in Sweden by the scientists at the Swedish Institute of Fibre and Polymer Research, found that there is no link between carpet usage and the incidence of asthma or allergies. What they did find was that even though carpet usage had steadily decreased since 1975, the occurrences of allergic reactions in the general population had increased.

In some situations people have perceived that carpet may have a negative impact on the indoor air quality. It has been shown that removing carpet does not impact the amount of allergies or asthma. Dr. Scott Schroeder, a pediatrician from Bronx, New York, noted that carpet was removed in the Bronx, New York School System and that it had no impact on the increase of asthma in the students there.

Carpet itself is not a source of mold and mildew without dirt and moisture. Visible mold is a manifestation of inadequate maintenance, excess moisture problems and poor HVAC ventilation. A recent research study of six Florida schools by Host/Racine Industries determined that mold and mildew are not associated with a particular surface, such as carpet. Eliminating sources of excessive moisture, such as water leaks, moldy HVAC ducts and humidity problems caused by turning off air conditioning in the night were steps that needed to be taken along with a concentrated effort to reduce humidity in the building.

DuPont in their White Paper entitled "Carpet and Indoor Air Quality" discussed bioaerosols from older carpet: "For older carpet, the area of concern is airborne suspension of irritants or allergenic material that either grows or accumulates in the carpet over time. With regard to the "growth" of microorganisms in carpet, we know that this does not occur to any significant extent at a relative humidity below 65 percent or in the absence of water leaks. In situations where humidity is high or water has intruded into the building, the potential for mold growth is greater regardless of flooring material. While biological materials can "accumulate" in carpet, it has been argued that carpet may actually be a benefit, since it traps and holds soils and dusts. Obviously, it becomes necessary to routinely remove this debris from the carpet via vacuum cleaning and periodic deep cleaning."

Carpet has been used happily by millions of satisfied customers for many years. The Carpet and Rug Institute offers information on carpet's role in the indoor environment, their indoor air quality (IAQ) testing program for carpet and for vacuum cleaners, and the benefits of carpet for allergy sufferers. Call CRI at (800) 882-8846 or visit CRI's website at www.carpet-rug.com.