How green is my carpet?

Are carpets safe? It depends on the person, on the carpet and on how you look after it.

What’s in a carpet?

Traditional or antique carpets may be made of wool, silk, cotton or other natural fibres; some use vegetable or mushroom-based colours. But over 80% of commercial carpets are made of nylon, followed by polypropylene (olefin / PET) and wool. [i] [ii] Commercial carpets usually include a primary backing material (most commonly made from polypropylene or polyester), a chemical adhesive and a secondary backing (cushion). [iii] Additional adhesives are frequently used when broadloom is installed. As a result, commercial carpets and padding typically emit volatile organic compounds (VOCs), especially when they are new.[iv] [v] One of these chemicals, 4-phenylcyclohexene (4-PC), is mainly responsible for the odour of new carpets.[vi]

Certain chemicals should be avoided. In particular, ozone-depleting chemicals like hydrochlorofluorocarbons (HCFC) may still be used in some carpets.[vii] Polybrominated diphenyl ethers (PBDEs), used as flame retardants, may be released into the air through aging and wear of products. Although PBDEs are not manufactured in Canada, and their import, use and sale are restricted, they could still be present in some older carpets. [viii] [ix]

Both new and older carpets may be treated with anti-stain, anti-microbial and/or anti-static products, which may be released into indoor air.[x] [xi] They can also trap pollutants, like dust, pesticides, mites and fungi, and may absorb odours from paint and furniture – releasing these as people walk on the carpet. [xii] [xiii] Older carpet can contain an astonishing load of dust, mites and mould.

Some people are sensitive to the many chemicals that may be present in carpets, and may experience nose and throat irritation with installation of new carpets. According to the Lung Association, we do not yet have enough information about the long-term health effects of exposure to some chemicals that can be used in carpets.[xiv] However, with good ventilation, VOC levels from new carpets are usually very low by 72 hours after installation.[xv]

Buying carpet

Indoor air quality can be protected when buying carpets. To help identify low emission carpets, the Canadian Carpet Institute (CCI) has adopted the US indoor air quality testing program.[xvi] Carpet samples are tested for total VOC, including 4-PC, styrene and formaldehyde. Those that meet emission criteria can display the “Green Label” logo; this label contains an identification number specifically assigned to a manufacturer for each carpet that meets these criteria. The CRI recently introduced its “Green Label Plus” program, which is even more stringent; consumers can access on-line information about products (including Canadian ones) that that meet this standard.[xvii]

Homeowners can protect indoor air quality when replacing carpets by

• · Before removal, vacuum the old carpet thoroughly to minimize dust particles, preferably with a HEPA filter;
• · Once the old carpet and backing are removed, vacuum the floor right away;
• · Where possible, unroll the new carpet in a well-ventilated space, outside the house, for at least 24 hours before installation;[xviii]
• · Once the new carpet is installed, ensure ample ventilation for 72 hours;[xix]
• · Anyone sensitive to chemicals should stay away from the home during removal of the old carpet and installation of the new one, and for the next few days. [xx]

Commercial carpet installers can also reduce emissions following the CRI’s Carpet Installation Standard (2011).[xxi]

In addition to its impact on indoor air quality, carpet has a substantial environmental footprint. In Canada, 500 to 600 million pounds of carpet go to landfill every year. Nylon, polypropylene and polyester are typically made from petroleum and are not biodegradable.[xxii] It was therefore high time, last year, when the Canadian carpet industry formed the Canadian Carpet Recovery Effort.[xxiii] [xxiv] Consumers can push these initiatives along by,

• · Choosing carpet, as well as padding and adhesives that are certified as low VOC emitters (GreenLabel or Green Label Plus); [xxv]
• · Choosing a carpet made from natural fibres – e.g., wool, or floor coverings of jute or cotton;[xxvi]
• · Watching for carpets using greener products – these are in development, e.g., a polyurethane backing that uses soybean oil derivatives, and a bonding adhesive that uses a by-product of the kraft wood pulping process;[xxvii]
• · If buying nylon, polypropylene or polyester, asking about recycled content for the carpet, backing and cushion; Some manufacturers offer carpets refurbished from used carpets (100% post-consumer content).[xxviii] (The US Carpet and Rug Institute (CRI) recommends that recycled content be stated as a percentage of total weight of the carpet. [xxix])
• · Choosing a vendor that will take old carpets back;[xxx]
• · Selecting a more durable carpet, which will require less frequent replacement; and
• · Finding out what the carpet has been treated with; for example, anti-mould treatments may be more of a health concern than the mould they are intended to prevent.[xxxi]

Finally, everyone with concerns about indoor air quality should keep their carpets clean:

• · vacuum frequently;
• · use non-toxic carpet cleaners; [xxxii] [xxxiii], and
• · don’t walk on your indoor carpets with outdoor shoes.

An indoor air filter can help too.

Dianne Saxe

Jackie Campbell

August 14 2011