How To Fix It

Why Is Indoor Air Quality Important?

As natural disasters increase in size and number every year, we hear more and more about climate change and pollution. We know that engine exhaust and wildfire smoke can cause the air we breathe to become polluted and carcinogenic. But what about the quality of the air inside?

Indoor Air Quality is important because when it’s compromised, it can have devastating short and long-term health effects. Poor indoor air quality can cause a wide range of health complications, from ailments such as headaches and nausea to life-threatening conditions like lung disease and cancer.

Many things can cause your indoor air to become polluted. Identifying these contaminants is important for your health and wellbeing. Keep reading to learn more about indoor air quality and how to keep your indoor air clean.

The Importance of Indoor Air Quality

Indoor Air Quality, abbreviated as IAQ, describes how clean and healthy the air inside a building is. It can be affected by many things that can lead to an array of health problems. 

IAQ-related issues may be immediately apparent, like congestion, headaches, and nausea, or appear years down the road through cases like cancer and lung disease. Keeping your air quality healthy is one of the best ways to keep you and your loved ones healthy.

Causes of Poor Indoor Air Quality

Poor indoor air quality is caused by contaminants and poor ventilation. Sometimes, these things are visible and obvious. Other times, we’ve no idea they’re there until we test the air.

The EPA divides causes of poor indoor air quality into the following categories:

  • Asbestos.
  • Biological Pollutants.
  • Carbon Monoxide (CO).
  • Cookstoves.
  • Formaldehyde/Pressed Wood Products.
  • Lead (Pb).
  • Nitrogen Dioxide (NO2).
  • Pesticides.
  • Radon (Rn).
  • Indoor Particulate Matter.
  • Secondhand Smoke/ Environmental Tobacco Smoke.
  • Volatile Organic Compounds (VOCs).
  • Wood Smoke.

Let’s find out how each cause affects IAQ and your health.

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Asbestos is a fiber found in rocks and soil. Because these fibers are strong and heat-proof, they have been used in building materials, automobile parts, and fire-proof fabrics for a long time. While the use of asbestos in the United States has declined sharply since the ’80s, it’s still not banned. We don’t mine it anymore, but asbestos still comes in through imports from other countries that still use it.

The most common sources of asbestos in buildings are things like insulation and floor tiles. If you’re planning a DIY project to remove those dated popcorn ceilings, you’d better test it for asbestos first.

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Have you ever seen those commercials for mesothelioma class-action lawsuits? Mesothelioma is a rare form of cancer caused by asbestos. Asbestos can also cause lung cancers and a condition called asbestosis.

Read: Why Air Conditioner Is Not Heating?

Biological Pollutants

“Biological Pollutants” is a fancy way of saying pollutants that are alive or came from something alive. This includes:

  • Pollen
  • Viruses
  • Bacteria
  • Mold and mildew
  • Household pets
  • Insect and pest droppings

Biological pollutants can cause allergies, asthma, and spread disease, which I’m sure we’re all aware of by now. Exposure to pest droppings and urine can cause severe health issues like Hantavirus.

Carbon Monoxide (CO)

There’s a reason many homes now have carbon monoxide alarms: CO is odorless and can be fatal in high doses. Lower levels cause fatigue, brain fog, nausea, dizziness, and confusion. Several years ago, a post on Reddit went viral after what the poster thought was a stalker turned out to be dangerous levels of CO in his home. It’s not something to mess with.

Carbon Monoxide can enter your home from automobile exhaust, tobacco smoke, leaky chimneys, gas stoves, heaters, or furnaces. To protect yourself from CO exposure, ensure that you’re using and cleaning gas appliances properly and get a few CO detectors.

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As mentioned above, gas cookstoves can increase your risk of CO exposure. However, cookstoves that burn solid fuels like wood or charcoal can also release pollutants into the air. Depending on what you’re burning, not only can you release CO, but also soot particles, methane, surfer dioxide, nitrogen oxides, carbon dioxide, and mercury.

Even electric stoves aren’t off the hook. Cooking can release particles into the air, especially if you burn something. To reduce the impact of cooking-related pollutants, always have your vent fan going when using the cookstove.

Formaldehyde/Pressed Wood Products

Formaldehyde is a chemical used to manufacture numerous building and household materials. The most common formaldehyde sources in homes include:

  • Particleboard.
  • Insulation.
  • Craft and home improvement supplies like glues, paints, and lacquers.
  • Preservatives found in medicines and cosmetics.
  • Household items like dishwashing liquids, fertilizers, and pesticides.
  • Cigarette smoke.

Formaldehyde is also a byproduct of fuel-burning appliances like gas or kerosene stoves.

The EPA is still researching the health effects of formaldehyde. So far, they’ve found it can cause irritation to areas like the eyes and throat, and high exposure may cause cancer. While the regulatory organization works to set limits and regulations on formaldehyde in products, keeping your house cool and humid helps reduce the rate at which this harmful chemical escapes into the air.

Lead (Pb)

Before we knew about the harmful effects of lead, it was used in everyday objects like paint, pipes, and gasoline. Now we know lead drastically alters the brain and nervous system, but it remains in many older homes.

The most likely cause of lead in your indoor air is improperly removing lead-based paint. However, it can also come from things like dirt tracked in from outside due to the high levels of lead released into the environment when lead was used in gasoline.

Nitrogen Dioxide (NO2)

Nitrogen dioxide is a compound typically released into the air as a byproduct of combustion. Gas stoves and kerosene heaters are the most common sources of this compound in homes, but NO2 is also found in tobacco smoke.

No2 has a long list of health effects, so you might want to stop smoking indoors (better still, quit altogether) and make a habit of switching on your vent fan when cooking. 


Pesticides are chemicals used indoors and outdoors to get rid of pests like insects and rodents. Exposure to these chemicals can cause headaches, dizziness, nausea, and irritation, among other symptoms. Long-term exposure can lead to liver, kidney, and endocrine and nervous system damage.

To reduce pesticide pollution in your home, try to use organic or biological pest control methods if possible. Always read the instructions to ensure you’re using the product properly, and ventilate your home well after application.

Radon (Rn)

Radon is a radioactive gas emitted when uranium, radium, and thorium break down. These metals occur naturally in rock, soil, and groundwater, so your risk level depends on the levels of those elements around your home. Radon most frequently leaches into homes via gaps and cracks.

Because radon occurs naturally, we’re constantly exposed to some level of it. However, radon is a carcinogen, and high levels of exposure can lead to lung cancer. In fact, radon is the number one cause of lung cancer for nonsmokers and the second leading cause overall. For those who smoke, radon exposure dramatically increases their chance of lung cancer. 

You can use radon test kits to determine the level of this harmful gas in your home. If the level is high, adding a radon-reduction system to your home can help cut down the amount in your air.

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Indoor Particulate Matter

Indoor particulate matter refers to solid or liquid particles that are small enough to be inhaled. This may include dust, dirt, mold spores, soot, and smoke. These particles may come from smoking, cooking, burning wood or candles, laser printers, construction, biological sources, and a ton of other sources outside your home.

Inhaling particulate matter can irritate the eyes, nose, and throat. It can also worsen coronary and respiratory diseases. 

Here are some of the measures you can take to reduce indoor air particulates:

  • Use exhaust fans when cooking
  • Install proper ventilation
  • Keep your home clean to reduce mold and dust
  • Install an air filter. 

Secondhand Smoke/ Environmental Tobacco Smoke

Everyone knows smoking is unhealthy, especially smokers. It’s the leading cause of lung disease. Unfortunately, cigarette smoke can also pollute your indoor air and affect those living with the smoker. 

The best way to combat this is to help the smoker quit. If quitting smoking isn’t an option for the smoker, come to an understanding to ban smoking indoors. The smoke toxins cling to everything, so simply opening a window isn’t good enough. 

Volatile Organic Compounds (VOCs)

Volatile Organic Compounds are the gasses released by certain products. You know how you can walk into a building and immediately smell if someone recently painted or cleaned it with bleach? That’s a result of VOCs. 

VOCs can come from any number of things, like paint, wood preservatives, aerosol sprays, cleaners, fuel, pesticides…the list goes on. Formaldehyde is an example of a VOC. While not all VOCs have a strong smell, many do.

The health effects of VOCs will depend on the product and the length of exposure time. The most common effects include:

  • Irritation.
  • Headaches.
  • Nausea.
  • Fatigue.
  • Dizziness.

The best way to reduce exposure in your home is to make sure the areas you’re using these types of products are well-ventilated and always follow the manufacturer’s instructions.

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How To Improve Your Indoor Air Quality?

Indoor air can become polluted by many things, but there are a few general ways you can work to keep your air clean:

  • Proper ventilation.
  • Use the exhaust fan when cooking.
  • Keeping up with housekeeping to reduce mold and dust.
  • Read and follow product labels on any chemical mixtures like cleaners or pesticides.
  • Use an air testing kit to check your air quality.
  • Don’t allow smoking indoors.
  • Before doing home projects, check for pollutants like lead or asbestos.
  • Purchase a HEPA air filter to reduce pollutants.


Numerous things can negatively impact the quality of our indoor air. Polluted indoor air can lead to many health problems, from nausea and headaches to cancer and disease. The best way to avoid air pollutants is to keep your house clean and ventilated.