Common products such as paint, insulation, rigid foam, Particle Board, plywood, duct liners, exhaust fumes and other chemical contaminants from indoor or outdoor sources, and biological contaminants can be trapped inside by the HVAC AC system. As this air is recycled using fan coils the overall oxygenation ratio drops and becomes harmful. When combined with other stress factors such as traffic noise, poor lighting, inhabitants of buildings located in a polluted urban area can quickly become ill as their immune system is overwhelmed. Certain VOCs, considered toxic chemical contaminants to humans, are used as adhesives in all common building construction products. These aromatic carbon rings / VOCs can cause acute and chronic health effects on the occupants of a building, including cancer, paralysis, lung failure, and others. Bacterial spores, fungal spores, mold spores, pollen, and viruses are types of biological contaminants and can all cause allergic reactions or illness described as SBS. In addition, pollution from outdoors, such as motor vehicle exhaust, can infiltrate into poorly designed buildings and contribute to poor indoor air quality, high ppm of CO and CO2. Adult SBS symptoms were associated with a history of allergic rhinitis, eczema and asthma.A 2015 study concerning the association of SBS and indoor air pollutants in office buildings in Iran found that, as carbon dioxide levels increase in a building, symptoms like nausea, headaches, nasal irritation, dyspnea, and throat dryness have also been shown to increase. Certain work conditions have been found to be correlated with specific symptoms.
Sick building syndrome (SBS) is a condition in which people in a building develop symptoms of illness or become infected with chronic disease from the building in which they work or reside. The outbreaks may or may not be a direct result of inadequate cleaning or inappropriate cleaning methods. SBS has also been used to describe staff concerns in post-war buildings with misplanned building aerodynamics, defects in the construction materials or assembly process and-or inadequate maintenance. Certain symptoms tend to increase in severity with the time people spend in the building; often improving over time or even disappearing when people are away from the building. SBS is also used interchangeably with "building-related symptoms", which orients the name of the condition around patients symptoms rather than a "sick" building. A 1984 World Health Organization (WHO) report suggested up to 30% of new and remodeled buildings worldwide may be subject of complaints related to poor indoor air quality. Other causes have been attributed to contaminants produced by outgassing of some types of building materials, volatile organic compounds (VOC), improper exhaust ventilation of ozone (byproduct of some office machinery), light industrial chemicals used within, or lack of adequate fresh-air intake/air filtration (see minimum efficiency reporting value).The main identifying observation is an increased incidence of complaints of symptoms such as headache, eye, nose, and throat irritation, fatigue, and dizziness and nausea. In fact the 1989 Oxford English Dictionary defines SBS in that way.