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Building-Related Illnesses


Carrie A. Redlich

, MD, MPH, Yale Occupational and Environmental Medicine Program Yale School of Medicine;

Efia S. James

, MD, MPH, Yale School of Medicine;

Brian Linde

, MD, MPH, Yale Occ and Env Medicine Program

Reviewed/Revised Nov 2023

Building-related illnesses are disorders that affect the lungs as well as other parts of the body and are caused by exposure to substances within buildings.

  • Building-related illnesses generally result from exposure to substances within buildings that have poor ventilation.

  • Symptoms vary but may include runny nose or congestion, respiratory symptoms, eye irritation, headaches, skin problems, difficulty concentrating, and fever.

  • Diagnosis usually includes evaluating the building environment and assessing the relationship between exposure and symptom development.

  • Treatment centers around improvement of air quality within the building, and potentially removal from exposure.

In industrialized countries, people spend more than 90 percent of their life (about 22 hours per day) indoors. Symptoms and illnesses related to indoor environments are common and can substantially impact health. It is important to recognize when symptoms are related to an indoor environment so that, where possible, exposures can be decreased or eliminated.

Building-related illnesses are a diverse group of disorders associated with a particular building or indoor environment. Commonly encountered building settings include offices, schools, restaurants, entertainment venues, and healthcare facilities. Recent renovations, refurnishing, or construction can be a potential source of exposure. In some cases, a discrete cause can be identified, but often identification is not possible because symptoms and illness are rarely caused by a single exposure. Most building-related illnesses are related to more than one type of exposure combined with inadequate ventilation.

Ventilation involves exchanging indoor air with outdoor air to create a comfortable environment. Poor ventilation can lead to the accumulation of indoor pollutants, such as dust, mold, allergens, secondhand smoke, cleaning products, perfumes, volatile organic compounds, and other chemicals. Outdoor air pollution, infectious agents, and bioaerosols can also contribute to indoor exposures.

In addition to ventilation-related problems, temperature and humidity are important factors in indoor environmental quality. Damp indoor environments and excessive moisture, such as from leaks or floods, favor the growth of molds and microorganisms, which are among the most common sources of building-related symptoms and illness.

Building-related illnesses can be

  • Specific

  • Nonspecific

Specific building-related illnesses

Specific building-related illnesses are those for which a link between a particular building or indoor environment and illness is proved. These illnesses can vary in severity. Examples include

Nonspecific building-related symptoms

Building-related symptoms are symptoms that occur in association with a specific indoor environment but are not easily categorized as a single definable illness. The term sick building syndrome has been used to refer to illnesses that occur in clusters of people within a building, but this term is being replaced by the term building-related symptoms. The symptoms of building-related illnesses are often very general and may include the following:

  • Itchy, irritated, dry, or watery eyes

  • Runny nose or nasal congestion

  • Throat soreness or tightness

  • Cough and chest congestion

  • Dry, itchy skin or unexplained rashes

  • Headache, lethargy, or difficulty concentrating

Diagnosis of Building-Related Illness

  • History and doctor's evaluation

  • Building or workplace evaluation

History and clinical evaluation

Doctors base the diagnosis of building-related illness on the person's exposure and findings from the history (including symptom onset, timing, and progression). They document any increased use of medications, medical visits, and sick days used.

Doctors ask people to describe their work and the other environments they frequent, including the size of the space, number of workers, ventilation, job tasks, and potential sources of exposure such as dust, chemicals, gases, cleaning products, mold, and microorganisms. Doctors also ask about any changes in the workplace or work processes that may coincide with the onset or worsening of symptoms. Similar symptoms in other occupants of the building, though not always present, can be a clue to building-related illness.

Building or workplace evaluation

A building or workplace evaluation can help doctors identify contributing factors to building-related illness or symptoms. Such an evaluation helps to identify potential exposures, such as water intrusion, mold, dust, odors, and temperature extremes, as well as to get a sense of the overall indoor environmental quality, including ventilation and fresh air intake. Sources of information about the indoor environment include the employer, previous environmental monitoring reports, the history of the building's usage (for example, office work, retail, or production), maintenance, and modifications, and other occupants.

Extensive air and surface sampling, such as for mold, is generally not necessary and is often costly. Most building-related illnesses are related to more than one exposure combined with inadequate ventilation.

Treatment of Building-Related Illnesses

  • Treatment of diagnosed condition

  • Building remediation

Treatment of diagnosed conditions is similar whether the illness is building-related or not. Treatments are given if necessary to relieve symptoms. For example, medications may be given to reduce fever or to treat asthma Drugs for Preventing and Treating Asthma Drugs allow most people with asthma to lead relatively normal lives. Most of the drugs used to treat an asthma attack can be used (often in lower doses) to prevent attacks. (See also Asthma... read more Drugs for Preventing and Treating Asthma (such as bronchodilators, which open the airways).

Remediation of exposures and optimizing the building ventilation are central to managing building-related symptoms and illness.

In the United States, reliable guidance on indoor air quality can be obtained through the U.S. Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention National Institute for Health and Safety (CDC-NIOSH), and Department of Public Health websites for individual states.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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