This article, written by Jack Noonan and Dr Vyt Garnys of CETEC was published in Facility Perspectives in June.
The emergence of green buildings and the emphasis on occupant health and wellbeing are two of the main reasons that many in the property and construction industry know what volatile organic
compounds (VOCs) are, and why their importance is no longer ignored.
Although many product manufacturers, architects, builders and sustainability managers have considered VOCs for a while, other important building stakeholders, such as tenants and facilities managers, are recognising their importance and their effect on day-to-day operations. Furthermore, as the definition and understanding of sustainability grows and matures from a simple focus on energy efficiency to a more holistic ‘triple bottom line’ approach, the importance of VOCs and material selection will continue to expand.
The World Health Organization defines VOCs as organic compounds with boiling points between 50 degrees Celsius and 260 degrees Celsius, excluding pesticides. The term encompasses a very large and diverse group of compounds containing carbon, with several thousand synthetic and naturally occurring chemicals that could fall into the category of a VOC. Importantly, over 900 VOCs have been identified in indoor air. Some common VOCs within the built environment, and their sources, can be seen in Table 1 (sourced from Health Canada).
Volatile organic compounds can be present within a wide range of building materials, including paint, adhesives, flooring materials, ceiling tiles, chairs, workstations and other products. While the content of a material is important, so too is the emission rate of Volatile organic compounds can be present within a wide range of building materials, including paint, adhesives, flooring materials, ceiling tiles, chairs, workstations and other products. While the content of a material is important, so too is the emission rate of the product; that is, the amount of VOCs that are emitted from the material over a period of time. As such, content is generally measured according to percentage by weight of volatile organic compound (%w/w), whereas emission rate is calculated by measuring concentrations over a set period of time, as micrograms per square metre per hour (μg/m2/hr). In a field setting, such as a commercial office building, there are two main methods for determining the level of VOCs within the indoor air. Field equipment, such as that based on photo ionisation, whilst sensitive for specific compounds, is not suitable for IEQ-VOC assessment and cannot identify individual chemicals. The key practical method is to draw a known amount of air through an adsorption tube, which is then analysed by a certified laboratory for total VOC and individual chemicals.
Importantly for the facilities manager and human resources, the World Health Organization recommends that the sum of VOCs within the indoor environment be less than or equal to 500 micrograms per cubic metre (μg/m3), with no individual chemical contributing more than 250μg/m3. This should be considered when implementing strategies relating to materials selection of new fit-outs, cleaning, maintenance regimes, and staff occupancy.
The importance of materials selection
Materials selection refers to the selection of a material (or product) based on a number of performance and cost factors. In its simplest
form, it can consist of selecting an end-use appropriate base material (for example, paint, polymer, metal, mineral). In more complex cases,
it can extend to selecting an approved product range for a major building project in order to meet requirements that may include:
- sustainability requirements (environmentally sustainable materials)
- indoor air quality (IAQ) or indoor environmental quality (IEQ) standards and voluntary product performance schemes (for example, Green Star, NABERS)
- industry requirements (for example, food, auto, chemical, pharmaceutical)
- life cycle analysis (LCA)
Materials selection is one of the most overlooked, but most important, factors in building and product design because it can have a significant effect on:
- total cost of the product, in situ, for the various stakeholders
- performance of the product, in situ
- indoor environmental quality of the facility
- product stewardship
Having conducted VOC emissions and content testing on building materials and products for over 20 years, Foray Laboratories Pty Ltd, a NATA-accredited subsidiary of CETEC, has established a database of emission results for over 1000 different products. Interestingly, there are some differences that can be seen between the use of local Australian products and products developed overseas. For example, vinyl produced in Australia has been shown to have a typical VOC emission rate of 0.05 to 0.20 mg/m2/hr, in contrast to non-Australian vinyl typically emitting 4 mg/m2/hr, or 20 times that of the Australian variants. Some examples of the VOC emission levels for various building materials are listed in Table 2. Often sealants and adhesives are hidden, and professional help is needed to determine the source of offending VOCs.
Voluntary product performance schemes and regulation
In Germany, Scandinavia and South Korea, there are regulations relating to the acceptability of building products for indoor use. Similar regulations do not exist in Australia; however, voluntary product performance schemes exist in order to drive a market change to sustainable and healthy building products. Some of these voluntary schemes include the following:
- Green Building Council of Australia’s Green Star
- Australasian Furnishing Research and Development Institute’s Green Tick
- Carpet Institute of Australia’s Environmental Certification Scheme
- Ecospecifier’s Global Green Tag
- Good Environmental Choice Australia’s Ecolabel
- Carpet and Rug Institute’s Green Label Plus.
Methods of measuring the VOC emissions or content from materials in accordance with the voluntary schemes listed above will obviously differ due to the differing requirements of the schemes. For example, some emissions tests are required to be carried out in a chamber for the period of 24 hours, while others may require testing for 7, 14, or 28 days. Within schemes, some tests, such as those for adhesives and sealants, will require an analysis of VOC content only, while others will require additional analyses of VOC emissions. They also differ in the range of VOCs that are analysed. For example, the stringent Green Label Plus scheme requires identification and quantification of numerous ‘chemicals of concern’, such as formaldehyde, acetaldehyde, benzene, caprolactam, 2-ethylhexanoic acid, 1-methyl-2-pyrrolidinone, naphthalene, nonanal, octanal, 4-phenylcyclohexene, styrene, toluene, and vinyl acetate.
Importantly, a wide range of Green Star tools have credits relating to indoor environment quality, which includes VOCs. This credit encourages product suppliers, designers and specifiers to use low-VOC emitting materials. By doing so, the project team can achieve additional Green Star credits (one point each) by using low VOC products for:
- carpets (or other flooring materials)
- adhesives and sealants.
Innovation and development continues to occur within voluntary schemes. For example, in the emerging Green Star Healthcare tool, there is a requirement for mattresses specified in the project to be low-emitting for VOCs. Furthermore, a research project by Cundall recently looked at how green rating systems in Australia had created positive changes within the industry. Interestingly, the green rating systems have not only reduced the environmental impact of products and materials in buildings, but also the accountability and transparency of their green credentials.