Poor IAQ Effects on Occupants

What is Sick Building Syndrome (SBS)?

Sick Building Syndrome (SBS) is a condition where building occupants experience acute health effects that seem to be directly linked to the time they spend in a particular building. The symptoms often disappear shortly after the person leaves the building. The term is used when no specific illness or cause can be identified. Essentially, the building itself is the source of the problem, making its occupants "sick."

How Buildings Can Make Us Sick

Many of the buildings we live and work in are designed to be airtight to conserve energy. While this is great for our heating and cooling bills, it can be bad for our health if not managed properly. A tightly sealed building can trap a variety of pollutants inside, and if the ventilation system isn't working correctly, these contaminants can build up to unhealthy levels.

Here's how different factors within a building can contribute to SBS:

• Chemical Pollutants: Many common materials found in buildings, like carpets, furniture, and paint, can release tiny amounts of chemicals into the air. These are known as volatile organic compounds (VOCs). Other pollutants can come from cleaning supplies, pesticides, and even office equipment like printers. Over time, these chemicals can accumulate and cause symptoms like headaches, dizziness, and irritation of the eyes, nose, and throat.

• Biological Pollutants: Moisture is a major culprit in creating unhealthy buildings. When water leaks or spills aren't dried out quickly, they can lead to the growth of mold, mildew, and bacteria. These biological contaminants release tiny spores and fragments into the air. When inhaled, they can trigger allergic reactions, asthma flare-ups, and other respiratory problems.

• Poor Ventilation: This is often the main reason for SBS. A building's ventilation system is designed to bring in fresh air and remove stale, polluted air. If the system is not maintained, is poorly designed, or is not used correctly, it can't do its job. This leads to a buildup of all the pollutants mentioned above, along with carbon dioxide (CO2​) exhaled by occupants. High CO2​ levels are linked to drowsiness and difficulty concentrating, which are classic symptoms of SBS.

The Health Effects

The health effects of SBS are not imaginary. They are a real physical response to a contaminated environment. The symptoms vary widely among individuals, but they commonly include:

• Headaches

• Fatigue and difficulty concentrating

• Dizziness and nausea

• Irritation of the eyes, nose, and throat

• Coughing and sneezing

• Dry, itchy skin

The key to identifying SBS is that the symptoms often improve or disappear when the person is away from the building—for instance, on weekends or during vacations.

It's common for patients to visit their doctor with a wide range of symptoms that don't seem to have a clear cause and don't respond to standard medications. When a medical issue, particularly a respiratory or allergic condition, seems to persist or recur for no apparent reason, doctors will often begin to look for environmental triggers. For example, a patient with a constant cough that doesn't improve with cough medicine might be unknowingly exposed to mold spores in their home. The medication might temporarily relieve the symptom, but it can't cure the underlying cause. In these situations, the medical team may recommend that the patient investigate their living or working environment, because the source of their health problem may not be a disease but rather the very air they're breathing. 

Preventing Sick Building Syndrome

As building scientists, our goal is to identify the sources of these problems and correct them. This often involves improving ventilation, controlling humidity, and removing biological contaminants. By ensuring that the buildings we live and work in are properly designed and maintained for indoor air quality (IAQ), we can create spaces that support our health rather than making us sick.