Most people spend a majority of the lives indoors, so the quality of indoor air is a major area of concern. From office buildings to daycare centers, from hospital operating rooms to courthouses, the health and economic impacts of poor indoor air quality are being felt around the nation. In mechanically ventilated buildings, the ventilation systems are frequently one cause of indoor air quality problems. These problems and their human health effects are diverse and sometimes difficult to diagnose. Some sources of indoor air pollution include building materials, new or damp carpets, cleaning products, as well as asbestos insulation and lead paint
