There is a widespread perception that carpet cannot be kept clean (sanitary) and that because of its inability to be kept clean, carpet contributes significantly to the deterioration of indoor environmental quality, especially indoor air quality. This unnecessary misconception often leads to policy decisions for removing carpet from many environments such as schools, health care facilities, and public agencies.
Decisions to remove carpet as a response to ineffective cleaning often deprive consumers and occupants of many desirable features provided by carpet, but simply transfers environmental problems related to cleaning breakdown to environments that do not have carpet.
Carpets that are not cleaned and properly maintained can cause many health problems inside the building environment. It is estimated that patients allergic to biopollutants (fungi, mites, cockroaches, bacteria) make 500,000 to 1,000,000 hospital visits each year. From a public health perspective, it is difficult to justify indoor carpet unless a routine and effective cleaning program can be assured. Such a program calls for properly trained personnel applying appropriate cleaning methods and using environmentally-sound cleaning technology.
Given that neglected carpets pose a health hazard, some public health and medical authorities now take a strong position against it. They argue that carpet should not be installed in any building unless its owners plan to clean it frequently using an external extraction method. Some health authorities even advocate passing a law that would make it illegal to install carpet where there is high humidity, moisture, or other conditions that promote the growth of biopollutants – regardless of the owners’ intention to clean it. (Please note that this author does not agree with their position. We can manage carpet very well without another law.)
Inevitably, however, the public health perspective has to be weighed against our aesthetic expectations and conventional practice. Aesthetically, carpeting is associated with luxury, with quiet and dignity – with lawyers’ offices, doctors’ waiting rooms, with small boutiques, expensive restaurants, and funeral parlors. Carpet does in fact help to reduce harsh noises produced by pedestrians and equipment. Conventionally, carpeting in many offices and businesses is a mark of success and an expression of style. It can provide thermal insulation, especially in winter. It is also kinder to the backs and feet of workers and customers who stand all day.
At the same time, it is wrong to assume that all carpet will ultimately get contaminated and adversely affect health. This is simply not the case. Most people who live and work on carpet are obviously healthy. Carpet retailers are not helpful when they sell their carpet on the basis it will never need cleaning.
Typically, manufacturers’ recommendations for cleaning provide adequate guidelines. They call for frequent vacuuming and periodic professional cleaning that emphasizes extracting foreign substances and minimizing residue. In the long run, these measures protect the carpet and promote environmental health.
Most people clean carpets because they look bad. Rarely does anyone acknowledge that their carpet needs to be cleaned to protect their health. In spite of this, every time we extract pollutants from carpets we enhance the quality of the indoor environment by reducing exposures and protecting health.
For some time, we have known that outside contamination levels, especially in soil, can reach the same concentrations indoors. Researchers have just begun to describe the chemical and biological contents of carpet dirt and house dust.
Studies also show that vacuuming with ineffective equipment does not reduce the level of fine particles indoors. Particles of less than one micron tend to pass through vacuum cleaning bags. They build up over time and can cause great harm as they penetrate deep into our lungs. Furthermore, studies show that soil gases such as the harmful decay products of radon and a variety of organic compounds including pesticides – enter the microenvironment and adhere to particles or the surfaces of carpet and fabric. Until those fibers are cleaned, the potential for human exposure and health risk remains high.
Carpet Maintenance Analysis
|Substances in Carpet||Mitigation guidance||Vacuuming Effect||Hot Water Extraction Effect|
|Soils||Walk-off Mat and Frequent Vacuuming||High||High|
|Atmospheric Dusts||Vacuuming, Cleaning and Ventilation||Moderate to High||High|
|Toxic PM||Walk-off Mat and Frequent Vacuuming||Moderate to High||High|
|Pollen||Walk-off Mat and Frequent Vacuuming||High||High|
|Fungi||Dry, Walk-off Mat and Frequent Vacuuming||High||High|
|Mycotoxin||Dry, Walk-off Mat and Frequent Vacuuming||Moderate to High||High|
|Mite||Dry, Frequent Vacuuming||Moderate to High||Moderate to High|
|Cockroach||Dry, Frequent Vacuuming||Moderate to High||Moderate to High|
|Cat and Dog||Activity Management||Moderate||Moderate to High|
|Endotoxin||Frequent Cleaning||Moderate to High||High|
Annual Book of ASTM Standards, “Strand Laboratory Method for Evaluation of Carpet-Embedded Dirt Removal Effectiveness of Household Vacuum Cleaners, Vol 15.07, 376-390, 1986.
ASTM D 5438-94. Standard Practice for Collection of Dust from Carpeted Floors for Chemical Analyses. American Society of Testing and Materials.
Ayliffe GAJ, et. al, Cleaning and Disinfection of Hospital Floors, Brit Med Journal, 2:442-445, 1966.
Gschwandtner, Gerhard, Dennis Sanders, Michael A. Berry, Measurements of Indoor Particulate Pollution from Household Vacuum Cleaning, paper presented at the 82nd Annual Meeting of the Air and Waste Management Association, Anaheim California, June 25-30, 1989.
Lefcoe, N.M. I.I. Incult, Archieve Environmental Health Vol. 22, pages 230-238, 1971.
Lefcoe, N.M. I.I. Incult, Archieve Environmental Health Vol. 30, pages 565-570, 1975.