Levels of contaminants in the air can be several times higher indoors than outdoors. This, combined with the fact that most adult Americans spend approximately 90% of their time indoors, illustrates the fact that an adult's major source of exposure to airborne contaminants can come from indoor sources. Poor indoor air quality is believed to lead to an increased incidence of respiratory symptoms, which, in turn, can lead to an increase in absenteeism or a loss in productivity. However, there have been few attempts to quantify the costs or potential savings that may be realised by improving building ventilation. Current data and building-specific information can be used to estimate the cost of increasing the ventilation in a poorly ventilated building and the expense of lost employee time that may result from poor ventilation conditions. Substantial overall savings may result from improved ventilation conditions.

KEYWORDS: comparing, employees, respiratory diseases, health, ventilation, air quality, indoor, exposure, contaminants, absenteeism, costs, productivity, buildings, air change rate, economics, sick buildings, air change rate