IAQ Problems Associated With Different Types of Flooring

Different types of flooring
Indoor air quality concerns with flooring
Decreasing IAQ problems associated with flooring

Different Types of Flooring

• Vinyl flooring: Sheet vinyl is made by taking a layer of a PVC (polyvinyl chloride) compound (usually a PVC resin mixed with plasticizers and other additives like fungicides) and putting it on a backing material such as paper or a foamed plastic material.¹ Of the 2.6 billion square feet of vinyl flooring shipped in 1992, 61 percent was sheet vinyl and 39 percent was vinyl tiles. In 1992, 66 percent of vinyl flooring was used in residential buildings and 34 percent in commercial buildings. A 1991 survey showed that vinyl flooring is found in 73 percent of all kitchens. Other flooring used in kitchens included ceramic tile (7 percent), carpeting (10 percent), and wood/other (9 percent). In bathrooms, vinyl flooring was found in 47 percent of homes, compared with ceramic tile (28 percent), carpeting (24 percent), and wood/other (17 percent).¹ Vinyl flooring may be sources of volatile organic compounds (VOCs) and odors, and may require high solvent materials for maintenance.
   

• Carpet: Carpet is a very common flooring used in homes, commercial facilities and schools. It is the first product to be thoroughly studied for its indoor air quality (IAQ) effects, and found to be a low-emitter of VOCs. The carpet industry voluntarily instituted an indoor air quality testing and labeling program in 1992. This program assures consumers that they can purchase carpet that will contribute minimal levels of VOCs into the air. The program was expanded to include carpet adhesives and cushions. When choosing any of these materials, make sure that the product carries the Green IAQ Label from the Carpet and Rug Institute (CRI). This is the only flooring specific industry program in place that assures acceptable IAQ performance of flooring. Carpet must be maintained so that settled dust and dirt is effectively removed. Carpet is also susceptible to mold growth if it remains chronically damp or wet. This may occur near water sources or areas where there is a constant moisture problem such as on concrete in damp basements, near leaking pipes or pipes with condensate on them, near water fountains, to name a few examples.
   

• Wood: For the environmentalist, wood flooring can be very attractive, especially if the wood comes from sustainably managed forests. Look for a stamp from the Forest Stewardship Council (FSC). This is the best way to make sure that the wood being used came from well-managed forests since the FSC has a certification process. Some of the drawbacks to wood are that it is more expensive than vinyl and must be periodically refinished to keep it looking good. While new water-based polyurethane varnishes are available, most varnishes and other floor finishes still give off large quantities of VOCs into the air. Though there are some low-VOC floor finishes available, they have not been popular since they are not as durable. Wood flooring may also be sources of formaldehyde if laminates are placed on pressed wood underlayments. The coatings and sealants may also be sources of formaldehyde.
   

• Linoleum: Cork and linoleum floorings are environmental choices because they are "natural" materials using a mixture of linseed oil, cork, wood dust and dyes. Cork flooring is available in tiles composed of compressed cork chips. However, check this type of flooring carefully since some are just vinyl flooring with the cork being used in place of the plastic foam layer. These products are sources of VOCs and formaldehyde, and can have unacceptable odors. The chemicals associated with linseed oil are very odiferous.
   

• Ceramic tile: Ceramic tile is another environmentally good choice since it is produced from natural clays, lasts longer than vinyl if properly installed, can be laid with Portland-cement-based grout, which does not give off any vapors, and it requires almost no maintenance. In addition, ceramic tiles can be made out of recycled materials such as ground glass, auto windshields, and old fluorescent light bulbs. On the down side, ceramic tile floors are hard, cold, and are more expensive to buy and install.

IAQ Concerns with Flooring

• Asbestos is found in some resilient floor tiles (such as vinyl asbestos, asphalt, and rubber) as well as on the backing of vinyl sheet flooring. Asbestos may also be found in the adhesives used for installing floor tiles. Sanding these tiles can release fibers, as can scraping or sanding the backing during removal. Determine whether resilient tile flooring contains asbestos before you begin removing them. This is particularly true of materials manufactured before 1980.
   

• VOCs emit from all of the flooring types. Volatile organic compound emissions are typically higher in the adhesives used to install the flooring. The vapors from these bonding agents can cause skin rashes or respiratory irritation. The VOCs from vinyl floorings are also a major source of contamination in the indoor air environment.² Only low-emitting materials should be used as listed by the CRI Green Label Program or GREENGUARD™. Another source of VOCs are those products used to clean the floors, particularly the hard surface flooring. High solvent and ammonia materials are used to strip and shine vinyl resilient materials. Hydrocarbon waxes are used on wood floorings. Most carpets are cleaned with minimal organic solvent, but one needs to be sure that carpet does not become too wet and that it is rapidly dry within 12 to 24 hours.
   

• Because solvent vapors can build up, it is important to have good ventilation or problems can occur. For example, at the Newark International Airport in September 2000, about 3 dozen people were hospitalized after complaining of headaches, dizziness, chest pains and sore throats and eyes in the area where a new terrazzo floor was being installed. Workers had been grinding down the surface of the fresh terrazzo, made of a combination of an epoxy resin and marble chips, when others began to complain that the strong solvent-like odor was making them dizzy. The VOCs usually found in the epoxy resins include phenols and xylenes.³
   

• Formaldehyde emissions may be seen from pressed wood products made using adhesives that contain urea-formaldehyde (UF) for sub-flooring. Since this subflooring has been a major source of VOC contamination, some designers have begun using less rigid non-VOC materials and formaldehyde-free materials as acceptable substitutes for pressed wood (particleboards and MDFs) in certain applications. Laminate floor systems can contain pressed wood or coating that emit formaldehyde.
   

• Mold can grow under any flooring material if moisture is excessive or standing water exists. Moisture from ground water or wet concrete should be avoided or corrected before the installation of any flooring. In some cases, a vapor barrier (like plastic sheeting) may need to be placed over the concrete with sub-flooring. Wet concrete may also react with resilient and carpet flooring to increase VOC emissions and odors.

Decreasing IAQ Problems Associated with Flooring

• Install environmentally friendly, low-emitting flooring.

• If adhesives are used, use low-emitting ones only.

• Ask manufacturers or suppliers to submit certification information to validate their product's participation in the CRI Green Label Program or equivalent IAQ program.

• Follow manufacturer's recommendations for installation and ventilation of the installation area. Do not over apply the adhesive and tack down product when possible.

• If practical, have the flooring product and cushion (if any) unwrapped and unrolled in a well-ventilated location before it is installed.

• Remove old flooring carefully and thoroughly clean up the area using HEPA vacuum systems before installation of new product

• Vacuum new flooring after installation to remove loose matter and particles generated by the installation process and general construction in the area.

• Air out the space well for a minimum of 48 hours following installation? or longer if odors persist.

• Clean and maintain the flooring following manufacturer's instructions. Use HEPA vacuum systems only.

• Do not install on damp floors or in areas where water intrusion or leakage is expected. Fix the water problem first.

• Use approved carpet-cleaning systems that show greater than 98 percent efficiency in the removal of dust, allergens and mold. Make sure that carpet is dry within 12 to 24 hours after cleaning.

References

1. Malin N, Wilson A. Should we phase out PVC? Environmental Building News. 1994;3(1): www.buildinggreen.com/features/pvc/pvc.html.

2. Yu C, Crump D. A review of the emission of VOCs from polymeric materials used in buildings. Building and Environment. 1998;33(6):357-374.

3. Noxious chemical fumes sicken workers at Newark, N.J., Airport. The Star? Ledger. September 20, 2000.