While subcultures of the architecture, construction, engineering and consumer communities have long been interested in indoor air quality (IAQ) issues, the general public's understanding of the topic can be traced to a specific point in time. In 1988, installation of new carpeting at the headquarters of the Environmental Protection Agency (EPA) in Washington, D.C., led to a flood of health complaints from the staff. The irony of the situation led to a large-scale questioning of how the very agency charged with managing environmental concerns could have been ignorant of IAQ issues to such a degree.

While no conclusive finding ever emerged from the EPA fiasco, most suspicion centered on a compound known as 4-PC, or 4-phenylcylohexene, an element released from the carpet's backing material. Since that time an entire industry has grown up around IAQ issues, and every major trade association with even a remote connection to the issue - from the National Association of Home Builders to the American Industrial Hygiene Association - have devoted considerable resources to understanding and mitigating adverse IAQ impacts.

This movement itself has coincided with what some have called an "institutionalization" of the environmental movement, a development perhaps most symbolized by the so-called "Green Building" movement. The building trades and the companies that supply them have realized that consumers are not only willing to pay a premium for "environmentally sensitive" commercial and residential spaces, but increasingly expect the buildings they inhabit to be "green." To some this means using building materials that are recycled or derived from sustainable sources, while to others it means using materials that require less energy for use or production. To consumers and the broader public in general, IAQ issues and green building issues are becoming more closely linked all the time.

Contributors to reduced indoor air quality include volatile organic compounds (VOCs), such as formaldehyde. Formaldehyde is a naturally-occurring compound often found in paints, finishes, and wood products, as well as carpeting, HVAC systems, foundation types and even lighting fixtures. Both VOCs and man-made compounds found in these types of materials break down or emit gasses over time. Poor IAQ has been linked to asthma, allergies and respiratory sensitivities.

These issues have traditionally been dealt with through ventilation strategies. However, as HVAC systems become increasingly more efficient, incremental improvements in their effect on IAQ are becoming more and more costly to implement. Also, improving HVAC capabilities often leads to increases in energy consumption, something that can turn off many concerned with environmental issues. Conversely, those whose primary concern has been saving energy have moved toward building much more "air-tight" structures which increase ventilation challenges. It is readily apparent that a conundrum exists here: when the focus is placed in solving IAQ issues through HVAC strategies, energy consumption becomes an issue. And when the focus is placed on solving energy issues through designing and building more airtight structures, IAQ issues become a concern.

Source Centered Strategies

To deal with these issues simultaneously, industry experts from both fields have begun endorsing a more holistic, "source-centered" strategy. That is, by using materials that result in fewer IAQ problems, there is less of a demand for energy-sapping HVAC remedies. And, increasingly, the very components to "source-oriented" pollutant reduction strategies often tend to have other environmentally-advantageous aspects, as well. For instance, one company manufactures medium density fiberboard with no formaldehyde added and which also uses 100 percent reclaimed wood fiber as a principal component. Medium density fiberboard is commonly used to make furniture, cabinetry, fixtures, architectural wood work and moulding products.

While cost considerations once posed the primary impediment to better IAQ compliance, a broader, more complex understanding of both IAQ and environmental considerations as they impact economics has since emerged. Traditional "environmental" economic analyses have begun to be more accepted and used in building circles. Many studies point to the effect improved indoor air quality can have on the productivity of people who work in the buildings. One such study, cited by Valentine Lehr in a recent issue of Heating, Piping, Air Conditioning, said that an increase in productivity due to improved indoor air quality of just one percent in a given office building can result in an economic return equal to more than 125 percent of the total energy cost for the structure's heating, cooling and electrical power consumption. That such thinking is now creeping into the building trades is significant.

As a result of this type of thinking, it is becoming more acceptable to erect buildings with higher initial costs in order to achieve higher IAQ and green building quotients, because consumers are more and more accepting that not only will they enjoy a healthier building that has less of an impact on the environment, but that doing so actually makes better economic sense over time. Installing wood floors instead of carpet or laminates, using materials that are low VOC, using more energy efficient heating and lighting schemes (such as solar heating or glass block windows) are a few of the "source-related" and "green building" strategies now used to deal with IAQ issues.

Early on in the building industry's recognition of these issues, attention was focused primarily on industrial facilities that were more sensitive to cost issues and which have used compounds or processes that impact IAQ as a part of their purpose for being, like chemical factories. Other facilities recognized as being IAQ-sensitive from the beginning included those, such as hospitals, where the quality of the indoor environment is crucial to the building's ability to function in its intended manner.

This zone of understanding first expanded to include office buildings, such as the EPA building, where large quantities of people and suspect compounds were placed together inside buildings not originally designed for maximum ventilation factors. More recently, governmental bodies at all levels have begun to include green building and IAQ concerns in building specifications. This trend was established at the highest level in September 1998 when President Clinton signed Executive Order 13101, which established the federal government's commitment to utilizing "environmentally preferable" products and services and defined such products as those that have "a lesser or reduced effect on human health," among other attributes. Today, virtually all new public facilities, as well as those intended to have a high degree of public interaction (such as dormitories or hotels) are being built with IAQ as one of the most important factors. And products designed to affect indoor air quality at the source are ever more frequently being specified.

As more and more people began to realize that these issues were being addressed in their places of work, they naturally began to ask how these issues were impacting them at home. Increasingly, builders and architects are responding to requests that the homes they design and build be IAQ and environmentally sensitive. Both the National Association of Home Builders (NAHB) and the American Institute of Architects have devoted considerable resources to addressing these topics. As a result, more and more builders, both spec and custom, are able to offer products that address these concerns. Some, like Vernon McKown of Oklahoma City, even offer a standard IAQ "upgrade" package on all homes built.

Even so, both builders and contractors still face the challenges that result from a lack of agreed-upon standards. Indeed, even a cursory foray into the IAQ and green building communities reveals that a cornucopia of alphabet soup agencies and organizations exists, each giving builders and consumers its own version of things. Many organizations are currently working toward the development of some baseline data or standards, but as of yet even the EPA has refrained from publishing concrete standards on how IAQ issues relate to health.

In the most basic sense, however, we do know that unvented carbon monoxide, allergens (mold, mildew, and dust mites resulting from excessive moisture), and VOC emissions can be both harmful to the lungs and uncomfortable. Because every structure is literally unique- based on siting, surroundings, inhabitants and use- the task of standardizing anything in terms of IAQ or environmental impact in a practical way remains truly daunting. In this area there have emerged new cases where specifiers must weigh the relative attributes of a product's environmental preferability against its potential contribution to IAQ. One such example lies in some new panel products derived from agriculture residue which have recently been introduced to the market. On the one hand, these engineered building panels have a positive story to tell in that they utilize binders which do not off gas harmful VOCs and they are derived from residual material that might otherwise go unused. However, these board products may also contribute spores of mold and mildew, a direct result of their basis in agricultural residuals, to the indoor environment at levels not associated with the wood-based panels they are intended to replace. As is often the case, these trade-offs must be weighed by the specifier.

The focus for both consumers and builders needs to be on providing alternatives that can, in a measurable way, improve both IAQ and environmental impacts. Incorporating "green" materials into a building plan as a part of a holistic, comprehensive effort to address health and environmental issues is key to this process. And while the cacophonous alphabet soup of agencies and organizations referred to above can be daunting, it also offers a tremendous wealth of information to help anybody, at any point in the IAQ or green building spectrum, to do a better job of incorporating these concerns into a project.

Those interested in learning about the federal government's latest efforts on IAQ and green building issues, can visit EPA at www.epa.gov/iaq. For general green building information, a good source is the United States Green Building Council, at www.usgbc.org. General IAQ materials and resources are available at the Indoor Air Quality Council, at www.iaqcouncil.org. And a third-party source that attempts to help building industry professionals weigh a variety of factors and offers insights into the building process can be found at www.ebuild.com. Each of these sites also offers links to many other related organizations.

Jeff Baker is specialty products manager for SierraPine Ltd., a leading manufacturer of specialty and environmentally preferable wood composite panel products. You can reach by calling (800) 676-3339 or by e-mail at jbaker@sierrapine.com.