How air quality affects human health
“Canadians spend approximately 90% of their time indoors, which highlights the importance of maintaining good indoor air quality for health and well-being.” [1]
We spend 90% of our time indoors — at home, at work, or even in public spaces like schools and offices. Yet, when we think about air pollution, we often focus on the outdoors. But the air inside our buildings may actually be more dangerous to our health.
Poor indoor air quality (IAQ) can trigger or worsen respiratory conditions like asthma and allergies, and long-term exposure is linked to serious health risks, including heart attacks, irregular heartbeats, reduced lung function, and even cancer (particularly lung cancer caused by radon).
“Air pollution is a major environmental health risk globally, causing an estimated 7 million premature deaths every year.” [1]
That is one in eight deaths worldwide — highlighting the urgent need to address air quality. Vulnerable groups, like children, the elderly, and people with pre-existing health conditions, are especially at risk.
The good news? Improving IAQ starts with awareness. Unlike outdoor pollution, which is complex to regulate, indoor air quality is something we can monitor and control.
Indoor versus Outdoor Air Quality
While outdoor pollution contributes to indoor air quality (through infiltration), the air inside our homes and workplaces is often more polluted. This is because buildings act like sealed containers, trapping pollutants from both inside and outside.
Modern buildings, designed for energy efficiency, are increasingly well-insulated and air-sealed to reduce heating and cooling costs. But this also means less natural ventilation, requiring complex fresh air exchange systems to maintain a healthy indoor environment and avoid accumulation of indoor pollutants. Thus indoor air quality is increasingly being influenced by factors like ventilation, sources of pollution, and the materials used in construction and furnishings.
“Indoor air quality (IAQ) is a major environmental health issue. Many homes have levels of certain pollutants, such as volatile organic compounds (VOCs) and radon, that are significantly higher than outdoor levels.” [1]
Common indoor pollutants are created through emmissions from many different sources and include:
- Particulate Matter (PM): particles with very small size can stay suspended in air for long periods of time, making their way into our lungs and even into the bloodstream (fine particles, <2.5 micron).
- Carbon Dioxide (CO2): Simply breathing in a poorly ventilated space can result in the depletion of oxygen (2) and accomulation of carbon dioxide (CO2), with high CO2 levels negatively affecting human cognition, especially in children [4] .
- Mold and Mildew: While mildew is more an an inconvenience which grows in damp, poorly ventilated areas, many molds grow under similar conditions and continuously produce spores and other toxins.
- Volatile Organic Compounds (VOCs): volatile chemicals which are irritants and/or toxins are constantly emitted by paints, cleaning supplies, furniture, carpets, and building materials. Exposure to VOCs can cause a wide range of allergy, neurological, and respiratory issues.
- Carbon Monoxide (CO): any system involving combustion, such as heating systems, gas stoves, or vehicles in attached garages can result in dangerous levels of CO, which has resulted in increasingly stringest changes to municipal regulations regarding CO alarms indoors.
- Radon: A naturally occurring radioactive gas that seeps into buildings from the soil. Radon is the leading cause of lung cancer among non-smokers yet infrequently monitored.
Improving indoor air quality is not just about health—it is about creating spaces that support well-being, productivity, and longevity. Whether you are a homeowner, a parent, or a workplace manager, taking control of your indoor environment is in your grasp.
Ready to start? A smart building is a healthy building, read more from Smart Habitats on how you can take the first step to improving your indoor air quality – developing awareness.
References:
[1] https://www.canada.ca/en/environment-climate-change/campaigns/canadian-environment-week/clean-air-day/indoor-quality.html https://www.canada.ca/en/health-canada/services/air-quality/outdoor-pollution-health.html
[2] https://www.who.int/teams/environment-climate-change-and-health/air-quality-energy-and-health/health-impacts https://www.who.int/news/item/25-03-2014-7-million-premature-deaths-annually-linked-to-air-pollution
[3] https://www.sciencedirect.com/science/article/pii/S036013232300358X