Building and Furnishing Materials for Improved Indoor Air Quality

 

People spend approximately 90% of their time indoors at homes, public buildings and offices where concentrations of many pollutants, including volatile organic compounds (VOCs), are frequently higher than the outdoor urban air. Adverse health effects can result from the buildup of several VOCs in the indoor air, including formaldehyde, benzene, toluene and xylene. Building materials and furnishings are sine sources of VOC emissions. Development of commercially viable building and furnishing materials with reduced emissions would allow for implementing more stringent codes that enable improvement of the indoor air quality.

Reconstituted (engineered) wood products have emerged in recent decades as popular building and furnishing materials. They are composed of wooden elements of various size and shape, bonded by a synthetic resin. Examples of reconstituted wood products are particleboard, medium density fiberboard (MDF) and hardwood plywood (made commonly with urea-formaldehyde resins), and oriented strandboard and softwood plywood (made with phenol-formaldehyde resins). Reconstituted wood products constitute the majority of indoor surfaces (building products, cabinets and furniture). They can emit a variety of VOCs into the indoor air environment; examples include formaldehyde, acetone, hexanal, propanol, butanone, benzene and benzadehyde. Synthetic resins are the primary sources of any formaldehyde emission from reconstituted wood products.

Some adverse effects of reconstituted wood products on the indoor air quality have created a need for development of low-emission reconstituted wood products, and for development of building codes that encourage their broad adoption. This need can be addressed in a fundamental way through development of lower-emission binders that meet relevant performance, cost and sustainability requirements. Development of refined inorganic polymer binders and compatible processing techniques could be a viable approach to addressing the need for reconstituted wood products that are friendlier to the indoor air quality.