Flooring Contributes To Poor Indoor Air Quality
Flooring and other products contribute to poor indoor air quality
Sustainability consultant Alan Best reveals growing concerns about the effect of flooring and some other products on worsening indoor air quality;
THERE is a clear focus these days on energy-efficient construction which is leading to increasing concerns about indoor air quality (IAQ) and the extent to which flooring and other products contribute to poor IAQ.
We spend most of our lives indoors and the air that we breathe inside buildings is generally of poorer quality than that outdoors even in cities with high volumes of traffic. This is due to indoor air containing relatively high concentrations of potentially harmful volatile organic compounds (VOC’S) and other airborne pollutants.
As we tighten up our buildings to reduce energy consumption one of the consequences is a reduction in air drawn in from outdoors to refresh the internally recycled air and this allows a cumulative build-up of pollutants. VOC levels increase significantly when activities such as painting are carried out.
According to a recent paper by safety science company UL, ‘Creating Healthier Furniture and Building Materials by Minimizing Chemical Emissions,’ VOC’S can attain levels around 1000 times greater than outdoors levels when high emissions materials like some paints and paint strippers are used and these pollutants can persist long after the product containing the VOC has been used.
The health risks associated with poor IAQ include asthma the incidence of which continues to rise year on year with one adult in nine in the UK now affected and one in 12 receiving active treatment. Asthma and its causes is therefore a very important public health issue and one which is the subject of major international medical studies.
Other less severe but common effects of exposure to poor quality air include eye, nose and throat irritation; allergic skin reactions; headaches; dizziness and fatigue. These effects are often associated with specific organic chemicals and may only occur above certain critical concentration levels.
A small number of commonly occurring VOC’s have been shown to cause cancer in animals and are either a known or suspected cause of some cancers found in humans. The following are a few of the most common VOC’s, where they are to be found and their known effects:
n Formaldehyde: This is a VOC that may be found in significant concentrations both indoors and outdoors. In buildings the main source are construction products and furniture made of pressed wood created with adhesives which use formaldehyde based resins.
Products include plywood, particleboard and medium density fibreboard used in flooring and subflooring and other materials such as furniture, shelving and panelling.
Formaldehyde has recently been classed as a Group 1 known human carcinogen by the International Agency for Research on Cancer. This VOC is known to be harmful at low concentrations and is also associated with decreased lung function and respiratory, eye, nose and throat irritation.
Acetaldehyde: This VOC is a chemical used in the manufacture of polyester resins and basic dyes and as a solvent in the rubber, tanning and paper industries.
Acetaldehyde may be found in both outdoor and indoor air and is commonly found in many flooring materials including laminates, linoleum, varnished wood, cork and pine. It is an important constituent of tobacco smoke which is banned from most public buildings, but with around 10 million adults still smoking it may be found in the indoor air of many homes.
This VOC is classed as a probable human carcinogen (Group B2) and is also known to irritate the mucous membrane, throat and respiratory tract in humans and lead to chronic respiratory disease as well as kidney and liver damage. At high levels of exposure serious lung and tissue necrosis may occur.
Btex compounds: These VOC’s are aromatic hydrocarbons emitted by many coatings and adhesives and include benzene, toluene, ethyl benzene and xylene. They are the most commonly occurring VOC’s and may be found in petroleum products such as heating oil. They are believed to be carcinogenic to humans and animals and prolonged exposure can lead to adverse health effects including kidney, liver and blood disorders.
Phenol: This may be found indoors in building materials such as engineered wood made with phenol-formaldehyde resin, vinyl flooring and wall coverings that use phenol as a thermal stabiliser. It can be used as a biocide in paints and can be found in cleaning products and disinfectants.
Phenol is also generated by wood burning fireplaces and from cigarette smoke. It is a strong irritant to the eyes and to the human respiratory system but is not considered to be a cause of cancer. However exposure to high concentrations of phenol can cause nausea, vomiting, convulsions and disorders of the heart and circulatory system.
Glycol ethers: These include various forms of ethylene glycol which is used as a raw material in the manufacture of polyester fibres and polyethylene terephthalate resins (PET) used in bottling. A small percentage is also used in industrial applications and antifreeze. In buildings it is mainly to be found in paints, coatings and adhesives as well as cleaning products.
Exposure to these chemicals can cause eye and upper respiratory tract irritation and if the exposure is prolonged then fatigue and nausea can occur as well as severe liver and kidney damage. Glycol ethers are not classed as carcinogenic but the authorities in California have determined that they may have toxic effects which include damage to the developing foetus.
One important consideration in reducing the build up to harmful concentrations of VOC’s in energy efficient buildings is through efficient ventilation to ensure that the air is refreshed by bringing in a flow of air from outdoors.
There are advanced heating and cooling systems now available such as energy recovery ventilators which are designed to increase the intake of outdoor air without significantly reducing the efficiency of the system or compromising energy savings.
Although there are various building codes and schemes such as BREEAM and LEED which look for low VOC emissions’ construction materials, there are no regulations covering VOC levels and there is a fundamental lack of evidence at to what levels are safe.
There are thought to be around 11,000 chemical compounds gassing off into the atmosphere from various product types and, although many of these are thought to be harmless, the full impacts on human health are unknown. The CE marking of flooring products under the European harmonised standard EN 14041, which is now part of the Construction Products Regulations, looks for low emissions’ of formaldehyde.
However the German authorities do not believe that this standard provides sufficient safeguards and they have gone further. They have introduced the AgBB/DIBt scheme which places stringent restrictions for VOC emissions from floor coverings, parquet coatings and adhesives.
This is the first step in an attempt to limit the emissions of volatile organic chemicals (VOC) from any construction product used in the German market.
suspect this will eventually be adopted across Europe. This means there will be new demand for low VOC flooring products and finishes and there is already a growing market for pressed wood products which are certified to have low formaldehyde emissions.
I believe there will be a move towards certification of products involving new and more demanding tests and new VOC standards. Some carpet manufacturers have achieved the Californian Green Label Plus Certification which I believe is the most stringent of the current global certification standards for VOC’s.
UL have developed their ‘Greenguard’ Certification of environmentally sustainable and low emitting furniture and flooring which offers a comprehensive assessment of more than 360 chemicals and sets chemicals emissions limits consistent with the most demanding global standards.
I am convinced that driving VOC levels down and improving indoor air quality will produce major health benefits for us all and there is clear evidence that working where the air quality is good make us more productive.
Alan Best, a sustainability consultant, is chair of the Flooring Sustainability Partnership, which he attends on behalf of Shaw Industries Group. He works with a number of construction related industries specialising in environmental certification, substitution of hazardous chemicals and waste reduction. Alan is co-author of the Croner ‘Essential Guide to REACH’. He also sits on a number of international bodies where he represents Shaw Industries Group.
This article has been reproduced from the Contract Flooring Journal website. You can find them at www.contractflooringjournal.co.uk.