When building occupants are becoming ill from their environment but the exact cause is unknown, it’s called Sick Building Syndrome.¹

This situation is a concern to anyone responsible for the health and well-being of building occupants. That includes building and facilities managers who are motivated to protect occupant health, but who also recognize the personal and potential financial losses a “sick” building causes.

Airborne contaminants are usually at the root of Sick Building Syndrome, although the specific cause of the problem may not initially be known.² Two primary categories of airborne pollutants are usually involved:³

• Biological contaminants. This includes viruses, bacteria, molds, and pollen, among other pollutants.
• Chemical contaminants. Volatile organic compounds (VOCs), tobacco smoke, and other sources of chemicals and odors.

The source of these contaminants may be outside the building itself. But in most cases, the contaminant source is indoors.⁴

Biological Contaminants

These contaminants are living organisms (or their byproducts), including:

• viruses, such as influenza and the SARS-CoV-2 coronavirus responsible for COVID-19 infections
• bacteria, such as legionella responsible for Legionnaire’s disease
• pollen from trees, grasses, and plants that can cause chronic allergies or worsen asthma symptoms
• mold, such as aspergillosis responsible for respiratory infections
• pet dander from dogs, cats, and rodents that can be tracked in on clothing and cause allergy-type symptoms
• dust mites common in bedding and other fabrics that can be transferred into buildings from employee clothing and belongings
• household dust whose particles can carry toxic chemicals on their surfaces
• cockroaches, whose droppings can be carried on personal belongings and cause allergic reactions

Biological contaminants are often the result of excessive moisture or high humidity. These conditions produce an ideal breeding ground for the growth and reproduction of living organisms like bacteria and mold.⁵ Bird, vermin, and insect droppings also fall into the biological contaminant category. These contaminants can carry bacteria, viruses, and compounds that can trigger allergies or cause infections in humans.⁶

Biological contaminants can accumulate just about anywhere in a building, including:

• ventilation ducts
• carpeting
• ceiling tiles
• insulation
• standing water
• furniture fabric
• humidifiers
• drain pans

During the COVID-19 pandemic that began in 2020, tiny airborne aerosols containing infectious SARS-CoV-2 coronavirus particles were found to be the primary mode of transmission for the deadly COVID-19 disease.⁷

These aerosols range from 0.06-0.13 microns in diameter.⁸ They’re typically emitted by infected individuals in coughs, sneezes, laughter, speaking, singing, and whispering.⁹ Due to their small size, infectious aerosols can stay airborne for hours, increasing the risk of airborne infection – especially in buildings with poor ventilation or low air exchange rates.¹⁰

Chemical Contaminants

Chemical contaminants are gas-phase contaminants. These are atoms and/or molecules smaller than 0.003 microns, the smallest particles. Chemical contaminants may originate from both indoor and outdoor sources.

The most common indoor sources are cleaning products and pesticides.¹¹ Many of these products release potentially dangerous chemicals, including volatile organic compounds (VOCs).

Other sources that emit VOCs can go by largely unnoticed, such as:¹²

• carpeting
• adhesives
• computers
• photocopiers
• heaters
• manufactured wood products
• lighting fixtures
• paint

Outdoor chemical contaminants can enter a building in any number of ways, including:

• doors
• windows
• cracks
• vents

Car exhaust, especially fumes from nearby parking garages, are also a major source of contaminants.

Other chemical contaminants that can make their way into a building include:

• outdoor pesticides, especially those used on large-scale agricultural operations whose airborne byproducts can travel for hundreds of miles
• smokestack emissions from industrial facilities and port operations
• agricultural and urban waste, such as the runoff of fertilizer, oil, plastics, and other substances that can emit chemicals into the environment
• forest fires that emit wildfire smoke containing dangerous chemicals like carbon monoxide and carbon dioxide
• smog, a nickname for ground-level ozone that builds up in the presence of heat and airborne gases like sulfur dioxide and nitrogen dioxide

Various effects of contaminants

Indoor contaminants can affect air quality alone or in combination with one another.

Because the variables are so vast, Sick Building Syndrome can be extremely difficult to diagnose. It’s worth looking for the root cause if occupants are complaining of the following symptoms regularly:

• irritated eyes, nose, or throat
• coughing, shortness of breath, or trouble breathing
• lethargy and chronic fatigue
• infectious diseases
• headaches, dizziness, or nausea
• skin irritation and rashes
• odor and taste sensations
• loss of smell and/or taste

All of these symptoms can be related to indoor air quality. Building managers and facilities managers should learn to recognize the potential sources and symptoms of sick building syndrome and be ready to take corrective action quickly when needed.

Steps building managers can take

Building and facilities managers can start with a Healthy Building Checklist while conducting an inspection of the facility, and should address a number of signs of potential problems.

Items on a Healthy Building Checklist should include:

• Are employees complaining of headaches, skin irritation, fevers, or other symptoms?
• Have there been any recent confirmed cases of COVID-19 in the building?
• Are there any identifiable increases in absenteeism?
• Is unusual dust or dirt visible near air diffusers or in the air?
• Are there any unpleasant odors detectable? These could include cleaning solvent odors, musty smells, or other odors.
• Is there any microbial growth — including mold or slime — on any visible surfaces or within the HVAC system?

If the answer to any of these questions is yes, take action before a limited problem becomes a big problem.

Conclusion

IQAir Solutions Engineers are available for consultation regarding the air quality in any building through the comprehensive Clean Air Facility program. They can also help develop customized air quality solutions.

Call IQAir at 866-500-4090 or request a bid to learn more about Clean Air Facility and how it can help address the health and productivity costs of Sick Building Syndrome.