Healthier buildings for healthier occupants

It is estimated that people spend at least 90 percent of their lives indoors. Much of this indoor time may be spent working inside of an airtight office building without operable windows, where exposure to air pollutants is significantly greater as compared to being outdoors.

Over the past several decades, office buildings have become increasingly airtight in order to maximize comfort and improve energy efficiency through central heating and cooling systems. But this effort has also translated into little control of one's physical environment, and ongoing exposure to potential allergens and materials used in such things as carpeting, furniture, printers, etc., and components of the building itself.

In the 1970s, the term "sick building syndrome" was coined to describe collective symptoms experienced by people working in the same environment, typically an office building. These workers would complain of symptoms such as fatigue, headaches, eye, nose or throat irritation, and sensitivity to odors not linked to any specific disorder other than time spent in the building. The World Health Organization suggested that up to 30 percent of new or remodeled buildings worldwide have sick-building complaints.

Although data is not always sufficient to make a conclusive link between symptoms and time spent in the building, some potential causes for the syndrome are thought to be due to inadequate ventilation -- combustion pollutants such as carbon monoxide from malfunctioning heating systems, or the release of volatile organic compounds (VOCs) from elements such as formaldehyde, which can be found in some carpet backings, resin finishes, and many other indoor materials or equipment. VOC levels may be up to 10 times higher indoors than outdoors.

With the advent of the green movement and LEED (Leadership in Energy & Environmental Design) certification, buildings are rapidly becoming "healthier." LEED recently certified its 12,000th commercial project that incorporates LEED standards for energy and water conservation, and promotion of indoor environmental quality, among other requirements.

Ironically, although many historic buildings have inadequate insulation and need to become more energy efficient, many already incorporate health-friendly features such as natural ventilation and light, and have greater cubic feet per minute (cfm) of outside air for each building occupant.

Building ventilation standards of the early to mid-1900s called for 15 cubic feet per minute of outside air for each occupant. With the oil embargo of 1973 and spurred efforts to conserve energy, these standards were reduced to five cfms per building occupant, thereby increasing indoor pollution. The cfm ventilation standard was recently revised upwards by the American Society of Heating, Refrigerating and Air-Conditioning Engineers to a minimum of 15 cfms per person, and 20 cfms in office spaces.