Mold and mildew (fungi) is probably one of the most underrated allergens in existence, and few allergy sufferers realize its ubiquitous nature. Fungi is everywhere at various levels. It can be found in the air, on surfaces such as tabletops, upholstered furniture, and bedding material, and is even found on various food products. Due to its microscopic size, few of us realize the frequency in which we are exposed to mold and mildew and other fungi. Those of us who are allergic to mold have very little sanctuary.
Airborne mold levels may vary of a daily basis, and of the thousands of species of fungi, an allergy sufferer only may be affected by a few species or certain levels of exposure. In addition, two individuals with the same allergic tendencies may require different levels of exposure to the same species of allergen to produce an allergic reaction.
Recently, a number of investigators have begun to explore mold as a primary allergen and have begun to search for ways to reduce exposure risks. Carpet was initially assessed for its tendency to capture fungi, and it was initially thought to be a source for mold released into the breathing zone. These initial theorists based their conclusions on the fact that if carpet held fungi, and fungi was found to be airborne above carpet, then carpet must be the source for the airborne fungi. Since carpet is used in a majority of indoor environments, these hypotheses became newsworthy. Few people took the time to investigate that the opposite (carpet simply absorbed by gravity and electrostatic properties those fungi which were airborne above it) may have been more relevant.
As a result, during the early years of evaluation of carpet and its property to release/retain fungi, researchers drew conclusions by extracting dust from carpet and collection of air samples above carpet and looking for similarities. The results were often erratic and rarely was a direct correlation established. The makeup of the air above carpet usually reflects the makeup of outdoor air rather than the fungal content in carpet. The fact that carpet contains fungi does not in itself indicate carpet is the source of airborne mold allergen.
In the study, cited in the chart above (see Alafia School Study) however, side by side portable classrooms were used to identify the differences, if any, that existed between carpeted environments and non carpeted environments. The two occupied classrooms were sampled concurrently. Both airborne and samples of dust were taken from each classroom and from each flooring surface. Even though the carpet classroom was seven years old (Versus one year with the other flooring surface) and had accumulated significant entrapped fungi through the years, the airborne fungi levels above the two flooring surfaces, were similar. In both instances, the composition of fungi found inside the classroom more closely represented the make up of outdoor air.
Another concern raised is the ability to remove entrapped fungi from the pile of carpet. This objection has been consistently raised by advocates of other flooring surfaces. This is a very valid concern, but one in which reality is very different from perception. Essentially, to effectively accomplish cleaning, contaminants must be extracted and removed from the facility. Testing has shown that this is more easily accomplished with carpet than other flooring surfaces, as shown above.
In order to effectively extract contaminants with other flooring surfaces, extraction equipment such as automatic scrubbers and vacuum cleaners must be used. Studies show that standard wet mopping and dust mopping of hard surfaces are not as effective as vacuuming and extracting of carpet. Given gravity, all horizontal surfaces are exposed to biological accumulation, however an effective method of removal must be initiated to ensure satisfactory results.
Mold, which is airborne everywhere, settles onto various surfaces, where it remains viable (able to become active growth) for long periods of time. Mold simply needs moisture (ambient moisture, such as humidity) a food source, (Organic materials-even soil), and ideal temperature 50-90 degrees. Once mold receives these catalysts, active growth begins. If you have ever found something "alive" in your refrigerator (moldy food), you should be aware that the source of the mold wasn't the refrigerator, the source was probably airborne mold that settled onto the food when it was opened on the counter. Even a sealed container in your "fridge" will grow mold if it was opened on the counter for more than 30 seconds. However, this is no reason to develop obsessive compulsive disorders, because we ingest vast quantities of mold each day in the air we breathe.
Carpet isn't the only building material that experiences problems with mold. The Paint industry has been haunted by the occurrence of mold for many years. While oil-based paints (organic solvents-linseed oil, safflower oil, sun flower oil) can be a food source for mold, latex-based paint do not have organic ingredients. Mold actually uses soil that accumulates on latex-based paints surface as its nutrient catalyst. Maintaining humidity levels within the home at 50% or less is the only answer to limiting active mold growth, but it will not eliminate the presence of mold. Homes that rely on gas, oil or other heat fuels do not dehumidify the air, allows sufficient moisture for mold growth to occur. Often condensation accumulates on walls and window sills as a result of these heat sources, which provides the moisture catalyst needed for active mold growth. A function of central HVAC systems is to "condition" the air, which equates to dehumidification.
Exterior coatings have similar issues, but it is impossible to dehumidify the neighborhood. In selecting exterior paint coatings, select high sheen products (satin, semi-gloss). While mold growth will still occur on these high sheen surfaces, these finishes are less porous than flat paint coatings and easier to remove mold and surface soils through yearly washing.
Mold allergy is one of the most common allergens and mold can be found in every environment. It is airborne, indoors and out, and there is no escaping exposure to mold. This section includes an insightful look into carpet and its relationship with mold allergies. Carpet removal does not eliminate allergies to mold, but carpet removal may exacerbate reactions. Carpet can actually have a positive impact on allergies, if proper carpet cleaning is performed. Dust mites, mold, mildew, fungi, and allergens are easily removed with proper carpet cleaning.
About the Author
Michael Hilton was the original creator of Carpet Buyers Handbook. Having owned and operated a carpet wholesale company, Hilton has a vast knowledge about all-things carpet related as well as other types of flooring.